USB PD Specification Viewer

1.1 - Overview............................................................................................................................................ (Page 34)
Page 34 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1 Introduction USB has evolved from a data interface capable of supplying limited power to a primary provider of power with a data interface. Today many devices charge or get their power from USB Ports contained in laptops, cars, aircraft or even wall sockets. USB has become a ubiquitous power socket for many small devices such as cell phones and other hand-held devices. Users need USB to fulfill their requirements not only in terms of data but also to provide power to, or charge, their devices simply, often without the need to load a driver, in order to carry out “traditional” USB functions. There are, however, still many devices which either require an additional power connection to the wall, or exceed the USB default current in order to operate. Increasingly, international regulations require better energy management due to ecological and practical concerns relating to the availability of power. Regulations limit the amount of power available from the wall which has led to a pressing need to optimize power usage. The USB Power Delivery Specification has the potential to minimize waste as it becomes a standard for charging devices that are not satisfied by [USBBC 1.2] or [USB Type-C 2.4]. Wider usage of wireless solutions is an attempt to remove data cabling but the need for “tethered” charging remains. In addition, industrial design requirements drive wired connectivity to do much more over the same connector. USB Power Delivery is designed to enable the maximum functionality of USB by providing more flexible power delivery along with data over a single cable. Its aim is to operate with and build on the existing USB ecosystem; increasing power levels from existing USB standards, for example [USBBC 1.2], enabling new higher power use cases such as USB powered Hard Disk Drives (HDDs), laptops and monitors. With USB Power Delivery the power direction is no longer fixed. This enables the product with the power (USB Host or Peripheral) to provide the power. For example, a display with a supply from the wall can power, or charge, a laptop. Alternatively, USB Chargers are able to supply power to laptops and other Battery powered devices through their, traditional power providing, USB Ports. USB Power Delivery enables Hubs (including Hubs embedded in other devices such as docks or monitors) to become the means to optimize power management across multiple peripherals by allowing each device to take only the power it requires, and to get more power when required for a given application. Optionally the Hubs can communicate with the PC to enable even more intelligent and flexible management of power either automatically or with some level of user intervention. USB Power Delivery allows low power cases such as headsets to Negotiate for only the power they require. This provides a simple solution that enables USB devices to operate at their optimal power levels. The Power Delivery Specification, in addition to providing mechanisms to Negotiate power also can be used as a side-band channel for standard and vendor defined messaging. The specification enables discovery of cable Capabilities such as supported speeds and current levels. Power Delivery enables alternative modes of operation by providing the mechanisms to discover, enter and exit Modes such as EPR Mode, USB4® Mode or Alternate Modes. 1.1 Overview This specification defines how USB Devices can Negotiate for more current and/or higher or lower voltages over the USB cable (using the USB Type-C® CC wire as the communications channel) than are defined in the [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] specifications. It allows Devices with greater power requirements than can be met with today's specification to get the power they require to operate from VBUS and Negotiate with external power sources (e.g., Chargers). In addition, it allows a Source and Sink to swap Power Roles such that a USB Device could supply power to the USB Host. For example, a display could supply power to a laptop to operate or charge its Battery. This specification also adds a mechanism to swap the Data Roles such that the upstream facing Port becomes the downstream facing Port and vice versa. It also enables a swap of the end supplying VCONN to a powered cable. The USB Power Delivery Specification is guided by the following principles:  Works seamlessly with legacy USB Devices.
1.2 - Purpose.............................................................................................................................................. (Page 35)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 35  Compatible with existing spec-compliant USB cables.  Minimizes potential damage from non-compliant cables (e.g., ‘Y’ cables etc.).  Optimized for low-cost implementations. This specification defines mechanisms to discover, enter and exit Alternate Modes defined either by a standard or by a particular vendor. These Alternate Modes can be supported either by the Port Partner or by a cable connecting the two Port Partners. The specification defines mechanisms to discover the Capabilities of cables which can communicate using Power Delivery. To facilitate optimum charging, the specification defines two mechanisms a USB Charger can Advertise for the device to use: 1) A list of Fixed Supply voltages each with a maximum current. The device selects a voltage and current from the list. This is the traditional model used by devices that use internal electronics to manage the charging of their Battery including modifying the voltage and current actually supplied to the Battery. The side-effect of this model is that the charging circuitry generates heat that can be problematic for small form factor devices. 2) A list of programmable voltage ranges, in SPR PPS Mode, each with a maximum current. The device re- quests a voltage (in 20mV increments) that is within the Advertised range and a maximum current. The USB PPS Charger delivers the requested voltage until the maximum current is reached at which time the USB PPS Charger reduces its output voltage so as not to supply more than the requested maximum current. During the high current portion of the charge cycle, the USB PPS Charger can be directly con- nected (through an appropriate safety device) to the Battery. This model is used by devices that want to minimize the thermal impact of their internal charging circuitry. 3) A list of adjustable voltage ranges, in SPR AVS Mode or EPR AVS Mode, each with a maximum current. The device requests a voltage (in 100mV increments) that is within the Advertised range and a maxi- mum current. The USB AVS Charger delivers the requested voltage. 1.2 Purpose The USB Power Delivery specification defines a power delivery system covering all elements of a USB system including USB Hosts, USB Devices, Hubs, Chargers and cable assemblies. This specification describes the architecture, protocols, power supply behavior, connectors and cabling necessary for managing power delivery over USB at up to 100W in SPR Mode and 240W in EPR Mode. This specification is intended to be fully compatible with and extend the existing USB infrastructure. It is intended that this specification will allow system OEMs, power supply and Peripheral developers adequate flexibility for product versatility and market differentiation without losing backwards compatibility. USB Power Delivery is designed to operate independently of the existing USB bus defined mechanisms used to Negotiate power which are:  [USB 2.0], [USB 3.2] in band requests for high power interfaces.  [USBBC 1.2] mechanisms for supplying higher power (not mandated by this specification).  [USB Type-C 2.4] mechanisms for supplying higher power. Initial operating conditions remain the USB Default Operation as defined in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2].  The DFP sources vSafe5V over VBUS.  The UFP consumes power from VBUS.
1.3 - Section Overview........................................................................................................................... (Page 36)
Page 36 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.2.1 Scope This specification is intended as an extension to the existing [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2] specifications. It addresses only the elements required to implement USB Power Delivery. It is targeted at power supply vendors, manufacturers of [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2] platforms, devices and cable assemblies. Normative information is provided to allow interoperability of components designed to this specification. Informative information, when provided, illustrates possible design implementation. 1.3 Section Overview This specification contains the following sections: Table 1.1 Section Overview Section Description Section 1, "Introduction" Introduction, conventions used in the document, list of terms and abbreviations, references, and details of parameter usage. Section 2, "Overview" Overview of the document including a description of the operation of PD and the architecture. Section 3, "USB Type-A and USB Type- B Cable Assemblies and Connectors" Mechanical and electrical characteristics of the cables and connectors used by PD. Section Deprecated. See [USBPD 2.0] for legacy PD connector specification. Section 4, "Electrical Requirements" Electrical requirements for Dead Battery operation and cable detection. Section 5, "Physical Layer" Details of the PD PHY Layer requirements Section 6, "Protocol Layer" Protocol Layer requirements including the Messages, timers, counters, and state operation. Section 7, "Power Supply" Power supply requirements for both Providers and Consumers. Section 8, "Device Policy" Device Policy Manager requirements. Policy Engine Atomic Message Sequence (AMS) diagrams and state diagrams Section 9, "States and Status Reporting" PDUSB Device requirements including mapping of VBUS to USB states. System Policy Manager requirements including descriptors, events, and requests. Section 10, "Power Rules" PDP Rating definitions for PD. Section A, "CRC calculation" Example CRC calculations. Section B, "Message Sequence Examples (Deprecated)" Scenarios illustrating Device Policy Manager operation. Deprecated Section C, "VDM Command Examples" Examples of Structured VDM usage.Section Deprecated. Section D, "BMC Receiver Design Examples" BMC Receiver Design Examples. Section E, "FRS System Level Example" FRS System Level Example.
1.4 - Conventions...................................................................................................................................... (Page 37)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 37 1.4 Conventions 1.4.1 Precedence If there is a conflict between text, figures, and tables, the precedence Shall be tables, figures, and then text. In there is a conflict between a generic statement and a more specific statement, the more specific statement Shall apply. 1.4.2 Keywords The following keywords differentiate between the levels of requirements and options. Table 1.2 Keywords Keyword Definition Conditional Normative Conditional Normative is a keyword used to indicate a feature that is mandatory when another related feature has been implemented. Designers are mandated to implement all such requirements, when the dependent features have been implemented, to ensure interoperability with other compliant devices. Deprecated Deprecated is a keyword used to indicate a feature, supported in previous releases of the specification, which is no longer supported. Discard See Discarded. Discarded Discard, Discards and Discarded are equivalent keywords indicating that a Packet when received Shall be thrown away by the PHY Layer and not passed to the Protocol Layer for processing. No GoodCRC Message Shall be sent in response to the Packet. Discards See Discarded. Ignore See Ignored. Ignored Ignore, Ignores and Ignored are equivalent keywords indicating Messages or Message fields which, when received, Shall result in no special action by the receiver. An Ignored Message Shall only result in returning a GoodCRC Message to acknowledge Message receipt. A Message with an Ignored field Shall be processed normally except for any actions relating to the Ignored field. Ignores See Ignored. Informative Informative is a keyword indicating text with no specific requirements, provided only to improve understanding. Invalid Invalid is a keyword when used in relation to a Packet indicates that the Packet’s usage or fields fall outside of the defined specification usage. When Invalid is used in relation to an Explicit Contract it indicates that a previously established Explicit Contract which can no longer be maintained by the Source. When Invalid is used in relation to individual K-codes or K-code sequences indicates that the received Signaling falls outside of the defined specification. May May is a keyword that indicates a choice with no implied preference. May Not May Not is a keyword that is the inverse of May. Indicates a choice to not implement a given feature with no implied preference. N/A N/A is a keyword that indicates that a field or value is not applicable and has no defined value and Shall Not be checked or used by the recipient. Normative See Shall. Optional Optional, Optionally and Optional Normative are equivalent keywords that describe features not mandated by this specification. However, if an Optional feature is implemented, the feature Shall be implemented as defined by this specification. Optional Normative See Optional. Optionally See Optional. Page 38 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.4.3 Numbering Numbers that are immediately followed by a lowercase “b” (e.g., 01b) are binary values. Numbers that are immediately followed by an uppercase “B” are byte values. Numbers that are immediately followed by a lowercase “h” (e.g., 3Ah) or are preceded by “0x” (e.g., 0xFF00) are hexadecimal values. Numbers not immediately followed by either a “b”, “B”, or “h” are decimal values. Reserved Reserved is a keyword indicating bits, bytes, words, fields, and code values that are set-aside for future standardization. Their use and interpretation May be specified by future extensions to this specification and Shall Not be utilized or adapted by vendor implementation. A Reserved bit, byte, word, or field Shall be set to zero by the sender and Shall be Ignored by the receiver. Reserved field values Shall Not be sent by the sender and Shall be Ignored by the receiver. Shall Shall and Normative are equivalent keywords indicating a mandatory requirement. Designers are mandated to implement all such requirements to ensure interoperability with other compliant devices. Shall Not Shall Not is a keyword that is the inverse of Shall indicating non-compliant operation. Should Should is a keyword indicating flexibility of choice with a preferred alternative; equivalent to the phrase “it is recommended that…”. Should Not Should Not is a keyword is the inverse of Should; equivalent to the phrase “it is recommended that implementations do not…”. Static Static is a keyword indicating that a field that never changes. Valid Valid is a keyword that is the inverse of Invalid indicating either a Packet or Signaling that fall within the defined specification or an Explicit Contract that can be maintained by the Source. Table 1.2 Keywords (Continued) Keyword Definition
1.5 - Related Documents....................................................................................................................... (Page 39)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 39 1.5 Related Documents Document references listed in Table 1.3, "Document References" are inclusive of all approved and published ECNs and Errata. Table 1.3 Document References Bookmark Reference Title [DPTC2.1] DisplayPortTM Alt Mode on USB Type-C Standard www.vesa.org. [IEC 60950-1] IEC 60950-1:2005 Information technology equipment – Safety – Part 1: General requirements: Amendment 1:2009, Amendment 2:2013. www.iec.ch. [IEC 60958-1] IEC 60958-1:2021 Digital Audio Interface Part:1 General. www.iec.ch. [IEC 62368-1] IEC 62368-1:2018 Audio/Video, information, and communication technology equipment – Part 1: Safety requirements. www.iec.ch. [IEC 62368-3] IEC 62368-3:2017 Audio/video, information, and communication technology equipment - Part 3: Safety aspects for DC power transfer through communication cables and ports www.iec.ch. [IEC 63002] IEC 63002:2021 Interoperability specifications and communication method for external power supplies used with computing and consumer electronics devices www.iec.ch. [ISO 3166] ISO 3166 international Standard for country codes and codes for their subdivisions. http://www.iso.org/iso/home/standards/country_codes.htm. [TBT3] see [USB4] Chapter 13 for ThunderboltTM 3 device operation. [UCSI] USB Type-C Connector System Software Interface (UCSI) Specification https:// www.usb.org/documents. [USB 2.0] Universal Serial Bus 2.0 Specification, https://www.usb.org/documents. [USB 3.2] Universal Serial Bus 3.2 Specification https://www.usb.org/documents. [USB Type-C 2.4] Universal Serial Bus Type-C Cable and Connector Specification, https://www.usb.org/ documents. [USB4] Universal Serial Bus 4 Specification (USB4®), https://www.usb.org/documents. [USBBC 1.2] Universal Serial Bus Battery Charging Specification plus Errata (referred to in this document as the Battery Charging specification). https://www.usb.org/documents. [USBPD 2.0] Universal Serial Bus Power Delivery Specification, https://www.usb.org/documents. [USBPDCompliance] USB Power Delivery Compliance Test Specification, https://www.usb.org/documents. [USBPDFirmwareUpdate 1.0] Universal Serial Bus Power Delivery Firmware Update Specification, https:// www.usb.org/documents. [USBTypeCAuthentication 1.0] Universal Serial Bus Type-C Authentication Specification, https://www.usb.org/ documents. [USBTypeCBridge 1.1] Universal Serial Bus Type-C Bridge Specification, https://www.usb.org/documents.
1.6 - Terms and Abbreviations........................................................................................................... (Page 40)
Page 40 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.6 Terms and Abbreviations This section defines terms used throughout this document. For additional terms that pertain to the Universal Serial Bus, see Chapter 2, “Terms and Abbreviations,” in [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2]. Table 1.4 Terms and Abbreviations Term Description (A)PDO Refers to both the PDO and APDO collectively. AC Supply AC Supplied Refers to the main AC power source typically provided to the wall AKA “mains”. Active Cable A cable with a USB Type-C plug on each end that incorporates data bus signal conditioning circuits. The cable supports the Structured VDM Discover Identity Command to expose its characteristics in addition to other Structured VDM Commands (Electronically Marked Cable see [USB Type-C 2.4]). Active Cable VDO VDO defining the Capabilities of an Active Cable. Active Mode A Mode which has been through the Mode Entry process but not the Mode Exit process. Adjustable Voltage Supply A power supply whose output voltage can be adjusted to an operating voltage within its Advertised range. These Capabilities are exposed by the Adjustable Voltage Supply (AVS) APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). Note: Unlike the SPR PPS, the SPR AVS and EPR AVS do not support current limit. Advertise An offer made by a Source in the Source_Capabilities/EPR_Source_Capabilities Message (e.g., an APDO or PDO). Alternate Mode Operation defined by a Vendor or Standard’s organization, which is associated with a SVID. The definition of Alternate Modes is outside the scope of USB-IF specifications. Entry to and exit from the Alternate Mode uses the Mode Entry and Mode Exit processes. As defined in [USB Type-C 2.4]. Alternate Mode Adapter A PDUSB Device which supports Alternate Modes as defined in [USB Type-C 2.4]. Note: Since an AMA is a PDUSB Device, it has a single UFP that is only addressable by SOP Packets. Alternate Mode Controller A DFP that supports connection to AMAs as defined in [USB Type-C 2.4]. A DFP that is an AMC can also be a PDUSB Host. AMA See Alternate Mode Adapter. AMC See Alternate Mode Controller. AMS See Atomic Message Sequence. APDO See Augmented Power Data Object. Assured Capacity Charger As defined in [USB Type-C 2.4]. This maps to a Charger with one or more Guaranteed Capability Ports. Assured Capacity Group As defined in [USB Type-C 2.4]. This maps to a group of Guaranteed Capability Ports. Atomic Message Sequence A fixed sequence of Messages as defined in Section 8.3.2, "Atomic Message Sequence Diagrams" typically starting and ending in one of the following states: PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready. An AMS is Non-interruptible. Attach Mechanical joining of the Port Pair by a cable. Attached USB Power Delivery Ports which are mechanically joined with USB cable. Attachment See Attach. Augmented Power Data Object Data Object used to expose a Source Port's or Sink Port's power Capabilities as part of a Source_Capabilities/EPR_Source_Capabilities or Sink_Capabilities/EPR_Sink_Capabilities Message respectively. An SPR PPS Data Object, SPR AVS Data Object and EPR AVS Data Object are defined. AVS See Adjustable Voltage Supply. AVS Mode A power supply, currently operating as an AVS, is said to be operating in AVS Mode. Battery A power storage device residing behind a Port that can either be a Source or Sink of power. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 41 Battery Slot A physical location where a Hot Swappable Battery can be installed. A Battery Slot might or might not have a Hot Swappable Battery present in a Battery Slot at any given time. Battery Supply A power supply that directly applies the output of a Battery to VBUS. This is exposed by the Battery Supply PDO (see Section 6.4.1.2.3, "Battery Supply Power Data Object"). BDO See BIST Data Object. BFSK See Binary Frequency Shift Keying. Bi-phase Mark Coding Modification of Manchester coding where each zero has one transition and a one has two transitions (see [IEC 60958-1]). Binary Frequency Shift Keying A Signaling Scheme now Deprecated in this specification. BFSK used a pair of discrete frequencies to transmit binary (0s and 1s) information over VBUS. See [USBPD 2.0] for further details. BIST Built-In Self-Test - Power Delivery testing mechanism for the PHY Layer. BIST Data Object Data Object used by BIST Messages. BIST Mode A BIST receiver or transmitter test mode enabled by a BIST Message. BIST Carrier Mode A BIST Mode in which the PHY Layer sends out a BMC encoded continuous string of alternating "1"s and "0"s. BIST Test Data Mode A BIST Mode in which the PHY Layer sends out a GoodCRC Message and then enters a test mode where it sends no further Messages, except GoodCRC Messages, in response to received Messages. BIST Shared Capacity Test Mode A BIST Mode applicable only to a Shared Capacity Group of Ports where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. BMC See Bi-phase Mark Coding. Cable Capabilities Capabilities offered by a Cable Plug. Cable Discovered USB Power Delivery Ports that have exchanged a Message and a GoodCRC Message response with a Cable Plug or a VPD using the USB Power Delivery protocol so that both the Port and the Cable Plug know that each is PD Capable and which Revision they each support. Cable Discovery See Cable Discovered. Cable Plug Term used to describe a PD Capable element in a Multi-Drop system addressed by SOP’ Packets/ SOP’’ Packets. Logically the Cable Plug is associated with a USB Type-C plug at one end of the cable. In a practical implementation, the electronics might reside anywhere in the cable. Cable Reset This is initiated by Cable Reset Signaling from the DFP. It restores the Cable Plugs to their default, power up condition and resets the PD communications engine in the cable to its default state. It does not reset the Port Partners but does restore VCONN to its Attachment state. Cable VDO VDO returned by the Cable Plug containing Cable Capabilities. Capabilities Features supported by a product. These can include, for example, power levels supplied/ needed, cable type, Battery support or [USB4] support. Capabilities Mismatch Indication from the Sink that the Source’s Advertised Capabilities don’t match the Sink’s needs. CC See Configuration Channel. Cert Stat VDO The Cert Stat VDO contains the XID assigned by USB-IF to the product before certification in binary format. Charge Through A mechanism for a VCONN Powered USB Device (VPD) to pass power and CC communication from one Port to the other without any interference or re-regulation. Charge Through Port The USB Type-C receptacle on a USB Device that is designed to allow a Source to be connected through the USB Device to charge a system to which it is Attached. Most common use is to allow a single Port USB Host to support a USB Device while being charged. Charger Provider whose primary purpose is to supply power to a Consumer or Consumers in order to charge their Battery. Chunk A MaxExtendedMsgChunkLen (26 byte) or less portion of a Data Block. Data Blocks can be sent either as a single Message or as a series of Chunks. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 42 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Chunked See Chunking. Chunked Extended Message Extended Message which has been broken up into Chunks. Chunking The process of breaking up a Data Block larger than MaxExtendedMsgLegacyLen (26-bytes) into two or more Chunks. Chunking Layer Part of the Protocol Layer responsible for Chunking. CL See Current Limit. Cold Socket A Port that does not apply vSafe5V on VBUS until a Sink is Attached. Collision Avoidance Mechanisms to prevent simultaneous communication by the Source, Sink and Cable Plug on CC. Command Request and response pair defined as part of a Structured Vendor Defined Message (see Section 6.4.4.2, "Structured VDM"). Configuration Channel Single wire used by the BMC PHY Layer Signaling Scheme (see [USB Type-C 2.4]). Connect See Connected. Connected USB Power Delivery ports that have exchanged a Message and a GoodCRC Message response using the USB Power Delivery protocol so that both Port Partners know that each is PD Capable. Constant Voltage A constant voltage feature of an SPR PPS Source. The SPR PPS Source output voltage remains constant as the load changes up to its Current Limit. Consumer The capability of a PD Port (typically a Device's UFP) to sink power from the power conductor (e.g., VBUS). This corresponds to a USB Type-C Port with Rd asserted on its CC wire. Consumer/Provider A Consumer with the additional capability to function as a Provider. This corresponds to a Dual- Role Power Port with Rd asserted on its CC wire. Continuous BIST Mode The BIST Mode where the Port or Cable Plug being tested sends a continuous stream of test data. Contract An agreement on both power level and direction is reached between a Port Pair. A Contract could be explicitly Negotiated between the Port Pair or could be an implicit power level defined by the current State. While operating in Power Delivery mode there will always be either an Explicit Contract or Implicit Contract in place. The Contract can only be altered in the case of a Negotiation/Re-negotiation, Power Role Swap, Fast Role Swap, Hard Reset, Error Recovery or failure of the Source. Control Message A Control Message is defined as a Message with the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. CRC CRC stands for Cyclic Redundancy Check. It is an error-detecting code used to determine if a block of data has been corrupted. CT-VPD See VCONN Powered USB Charge Through Device. Current Limit A current limiting feature of an SPR PPS Source. When a Sink operating in SPR PPS mode attempts to draw more current from the Source than the requested Current Limit value, the Source reduces its output voltage so the current it supplies remains at or below the requested value. Note: Current Limit is not supported by SPR AVS and EPR AVS Sources. CV See Constant Voltage. Data Block An Extended Message Payload data unit. The size of each type of Data Block is specified as a series of bytes up to MaxExtendedMsgLen bytes in length. This is distinct from a Data Object used by a Data Message which is always a 32-bit object. Data Message A Data Message consists of a Message Header followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is always a non-zero value. Data Object A Data Message Payload data unit. This 32-bit object contains information specific to different types of Data Message. For example Power, Request, BIST, and Vendor Data Objects are defined. Data Reset Process which resets USB Communication. Data Role A Port Partner will be in one of two Data Roles; either DFP (USB Host) or UFP (USB Device). Data Role Swap Process of exchanging the Data Roles between Port Partners. Dead Battery A device has a Dead Battery when the Battery in a device is unable to power its functions. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 43 Default Contract An agreement on current at 5V is reached between a Port Pair based on USB Type-C current ([USB Type-C 2.4]). Detach Mechanical unjoining of the Port Pair by removal of the cable. Detached USB Power Delivery Ports which are no longer mechanically joined with USB cable. Detaches See Detach. Device When lower cased (device), it refers to any USB product, either USB Device or USB Host. When in upper case refers to a USB Device (Peripheral or Hub). Device Policy Policy applied across multiple Ports in a Source or Sink. Device Policy Manager Module running in a Source or Sink that applies Device Policy to each Port in the device, as Local Policy, via the Policy Engine. DFP See Downstream Facing Port. DFP VDO VDO returned by the DFP containing Capabilities. Differential Non-Linearity The difference between an ideal LSB step, and the real observable LSB step when the Power Source is operating in either PPS or AVS mode. A DNL of 0 indicates that the step is ideal. If DNL is positive the step is larger than the ideal LSB, and if it is negative then the step is smaller than ideal. Discovery Process Command sequence using Structured Vendor Defined Messages resulting in identification of the Port Partner and Cable Plug, and their supported SVIDs and Alternate Modes. DNL See Differential Non-Linearity. Downstream Facing Port Indicates the Port's position in the USB topology which typically corresponds to a USB Host root Port or Hub downstream Port as defined in [USB Type-C 2.4]. At connection, the Port defaults to operation as the Source and as a USB Host (when USB Communication is supported). DPM See Device Policy Manager. DRD See Dual-Role Data. DRP See Dual-Role Power. Dual-Role Data Capability of operating as either a DFP or UFP. Dual-Role Data Port A Port capable of operating as DRD. Dual-Role Power Capability of operating as either a Source or Sink. Dual-Role Power Device A product containing one or more Dual-Role Power Ports that can operate as either a Source or a Sink. Dual-Role Power Port A Port capable of operating as a DRP. EM See Extended Message. End of Packet K-code marker used to delineate the end of a Packet. EOP See End of Packet. EPR See Extended Power Range. EPR AVS A power supply operating in EPR Mode whose output voltage can be adjusted to an operating voltage within its Advertised range. Unlike SPR PPS it does not support current limit. The AVS Capabilities are exposed by the Adjustable Voltage Supply APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). EPR AVS Mode A EPR Source, currently operating in an EPR AVS Contract, is said to be operating in EPR AVS Mode. EPR Cable A cable which is rated to operate in both SPR Mode and EPR Mode. EPR Capabilities The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. EPR Capable A product which has the ability to operate in EPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 44 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 EPR Mode A Power Delivery mode of operation where maximum allowable voltage is 48V. The Sink complies to the requirements of [IEC 62368-1] for operation with a PS3 Source. The Source complies to the requirements of [IEC 62368-1] for operation with a PS3 Sink. The cable complies with [IEC 62368-1]. Entry into the EPR Mode requires that an EPR Source is Attached to an EPR Sink with an EPR Cable. The EPR Source will only enter the EPR Mode when requested to do so by the Sink and it has determined it is Attached to an EPR Sink with an EPR Capable cable. Only the EPR_Source_Capabilities and the EPR_Request Messages are allowed to Negotiate EPR Explicit Contracts. The SPR Mode Messages (Source_Capabilities and Request) are not allowed to be used while in EPR Mode. EPR (A)PDO Fixed Supply PDO that offers either 28V, 36V or 48V. Adjustable Voltage Supply (AVS) APDO whose Maximum voltage is the highest Fixed Supply PDO voltage in the EPR_Source_Capabilities Message and no more than 240W. EPR Sink A Sink that supports both SPR Mode and EPR Mode. EPR Sink Port A Port exposed on an EPR Sink. EPR Source A Source that supports both SPR Mode and EPR Mode. EPR Source Port A Port exposed on an EPR Source. Error Recovery Port enters the ErrorRecovery State as defined in [USB Type-C 2.4]. Explicit Contract An agreement reached between a Port Pair as a result of the Power Delivery Negotiation process. An Explicit Contract is established (or continued) when a Source sends an Accept Message in response to a Request Message sent by a Sink followed by a PS_RDY Message sent by the Source to indicate that the power supply is ready. This corresponds to the PE_SRC_Ready State for a Source Policy Engine and the PE_SNK_Ready State for a Source Policy Engine. The Explicit Contract can be altered through the Re-negotiation process. Extended Capabilities An Extended Message containing Capabilities information. Extended Control Message An Extended Message containing control information only. Extended Message A Message containing Data Blocks. The Extended Message is defined by the Extended field in the Message Header being set to one and contains an Extended Message Header immediately following the Message Header. Extended Message Header Every Extended Message contains a 16-bit Extended Message Header immediately following the Message Header containing information about the Data Block and any Chunking being applied. Extended Power Range Extends the power range from a maximum of 100W (SPR) to a maximum of 240W (EPR). When operating in the EPR Mode, only EPR specific Messages (the EPR_Source_Capabilities Message and the EPR_Request Message) are used to Negotiate Explicit Contracts. External Supply Power supply external to the device. This could be powered from the wall or from any other power source. Fast Role Swap Process of exchanging the Source and Sink Power Roles between Port Partners rapidly due to the disconnection of an external power supply. Fast Role Swap Request An indication from an Initial Source to the Initial Sink that a Fast Role Swap is needed. The Fast Role Swap Request is indicated by driving the CC line to ground for a short period; it is not a Message or Signaling. First Explicit Contract The Explicit Contract that immediately follows an Attach, power on Hard Reset, Power Role Swap or Fast Role Swap event. Fixed Battery Fixed Batteries A Battery that is not easily removed or replaced by an end user e.g., requires a special tool to access or is soldered in. Fixed Supply A well-regulated fixed voltage power supply. This is exposed by the Fixed Supply PDO (see Section 6.4.1.2.1, "Fixed Supply Power Data Object") Frame Generic term referring to an atomic communication transmitted by PD such as a Packet, Test Frame or Signaling. FRS See Fast Role Swap. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 45 Guaranteed Capability Port A Guaranteed Capability Port is always capable of delivering its Port Maximum PDP and indicates this by setting its Port Present PDP to be the same as its Port Maximum PDP except when limited by the cable’s Capabilities. This is a Static capability. Hard Reset This is initiated by Hard Reset Signaling from either Port Partner. It restores VBUS to USB Default Operation and resets the PD communications engine to its default State in both Port Partners as well as in any Attached Cable Plugs. It restores both Port Partners to their default Data Roles and returns the VCONN Source to the Source Port. A DRP Source Port operating as a Source will continue to operate as a Source. Host See USB Host. Hot Swappable Battery A Battery that is easily accessible for a user to remove or change for another Battery. Hub A USB Device that provides additional connections to the USB. ID Header VDO The VDO in a Discover Identity Command immediately following the VDM Header. The ID Header VDO contains information corresponding to the Power Delivery Product. Idle Condition on CC where there are no signal transitions within a given time window. See Section 5.8.6.1, "Definition of Idle". Implicit Contract An agreement on power levels between a Port Pair which occurs, not because of the Power Delivery Negotiation process, but because of a Power Role Swap or Fast Role Swap. Implicit Contracts are transitory since the Port Pair is required to immediately Negotiate an Explicit Contract after the Power Role Swap. An Implicit Contract Shall be limited to USB Type-C current (see [USB Type-C 2.4]). Initial Sink Sink at the start of a Power Role Swap or Fast Role Swap which transitions to being the New Source. Initial Source Source at the start of a Power Role Swap or Fast Role Swap which transitions to being the New Sink. Initiator The initial sender of a Command request in the form of a query. Invariant PDOs A Source Port that offers Invariant PDOs will always Advertise the same PDOs except when limited by the cable. IoC The Negotiated current value as defined in [IEC 63002]. IR Drop The voltage drop across the cable and connectors between the Source and the Sink as defined in [USB Type-C 2.4]. It is a function of the resistance of the ground and power wire in the cable plus the contact resistance in the connectors times the current flowing over the path. K-code Special symbols provided by the 4b5b coding scheme. K-codes are used to signal Hard Reset and Cable Reset and delineate Packet boundaries. Local Policy Every PD Capable device has its own Policy, called the Local Policy that is executed by its Policy Engine to control its power delivery behavior. The Local Policy at any given time might be the default policy, hard coded or modified by changes in operating parameters or one provided by the system USB Host or some combination of these. The Local Policy Optionally can be changed by a System Policy Manager. LPS Limited Power Supply as defined in [IEC 62368-1]. LSB An abbreviation for Least Significant Bit. Managed Capability Port A Managed Capability Port can have its Port Present PDP set to a different value than its Port Maximum PDP. Its Port Present PDP value can be dynamic and change during normal operation. Message The Packet Payload consisting of a Message Header for Control Messages and a Message Header and data for Data Messages and Extended Messages as defined in Section 6.2, "Messages". Message Header Every Message starts with a 16-bit Message Header containing basic information about the Message and the PD Port’s Capabilities. Messaging Communication in the form of Messages as defined in Section 6, "Protocol Layer". Modal Operation Operation where there are one or more Active Modes. Modal Operation ends when there are no longer any Active Modes. Mode Mode is a general term used to describe a particular type of operation of a given device. Examples of modes are: Alternate Mode, EPR Mode, SPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 46 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Mode Entry Process to start operation in a particular Mode. Mode Exit Process to end operation in a particular Mode. Multi-Drop PD is a Multi-Drop system sharing the Power Delivery communication channel between the Port Partners and the cable. Negotiate See Negotiation. Negotiated See Negotiation. Negotiation This is the PD process whereby: 1) The Source Advertises its Capabilities. 2) The Sink requests one of the Advertised Capabilities. 3) The Source acknowledges the request, alters its output to satisfy the request and informs the Sink. The result of the Negotiation is a Contract for power delivery/consumption between the Port Pair. New Sink Sink at the end of a Power Role Swap or Fast Role Swap which has transition from being the Initial Source. New Source Source at the end of a Power Role Swap or Fast Role Swap which has transition from being the Initial Sink. Non-interruptible There cannot be any unexpected Messages during an AMS; it is therefore Non-interruptible. An AMS starts when the first Message in the AMS has been sent (i.e., a GoodCRC Message has been received acknowledging the Message). See Section 8.3.2.1.3, "Atomic Message Sequences". OCP Over-Current Protection. OTP Over-Temperature Protection. OVP Over-Voltage Protection. Packet One entire unit of PD communication including a Preamble, SOP*, Payload, CRC and EOP as defined in Section 5.6, "Packet Format". Passive Cable Cable with a USB plug on each end at least one of which is a Cable Plug supporting SOP’ that does not incorporate data bus signal conditioning circuits. Supports the Structured VDM Discover Identity to determine its characteristics (Electronically Marked Cable see [USB Type-C 2.4]). Note: This specification does not discuss Passive Cables that are not Electronically Marked. Passive Cable VDO VDO defining the Capabilities of a Passive Cable. Payload Data content of a Packet, provided to/from the Protocol Layer. PD USB Power Delivery PD Capable A Port that supports USB Power Delivery. PD Connection See Connected. PD Power The output power, in Watts, of a Source, as specified by the manufacturer and expressed in Fixed Supply PDOs as defined in Section 10, "Power Rules". PD SID See USB-IF PD SID. PDO See Power Data Object. PDP See PD Power. PDP Rating The PDP Rating is the same as the Manufacturer declared PDP for a Source Port except where there is a fractional value, in which case the PDP Rating corresponds to the integer part of the Manufacturer declared PDP Rating (see Section 6.4.11.2, "Port Maximum PDP Field"). PDUSB USB Device Port or USB Host Port that is both PD Capable and capable of USB Communication. See also PDUSB Host, PDUSB Device and PDUSB Hub. PDUSB Device A USB Device with a PD Capable UFP. A PDUSB Device is only addressed by SOP Packets. PDUSB Host A USB Host which is PD Capable on at least one of its DFPs. A PDUSB Host is only addressed by SOP Packets. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 47 PDUSB Hub A port expander USB Device with a UFP and one or more DFPs which is PD Capable on at least one of its Ports. A PDUSB Hub is only addressed by SOP Packets. A self-powered PDUSB Hub is treated as a USB Type-C Multi-Port Charger. PDUSB Peripheral A USB Device with a PD Capable UFP which is not a PDUSB Hub. A PDUSB Peripheral is only addressed by SOP Packets. PE See Policy Engine. Peripheral A physical entity that is Attached to a USB cable and is currently operating as a USB Device. PHY Layer The Physical Layer responsible for sending and receiving Messages across the USB Type-C CC wire between a Port Pair. Policy Policy defines the behavior of PD Capable parts of the system and defines the Capabilities it Advertises, requests made to (re)Negotiate power and the responses made to requests received. Policy Engine The Policy Engine interprets the Device Policy Manager’s input to implement Policy for a given Port and directs the Protocol Layer to send appropriate Messages. Port An interface typically exposed through a receptacle, or via a plug on the end of a hard-wired captive cable. USB Power Delivery defines the interaction between a Port Pair. Port Pair Two Attached PD Capable Ports. Port Partner A Contract is Negotiated between a Port Pair connected by a USB cable. These ports are known as Port Partners. Power Conductor The wire that delivers power from the Source to Sink. For example, USB’s VBUS. Power Consumer See Consumer. Power Data Object Data Object used to expose a Source Port’s or Sink Port’s power Capabilities as part of a Source_Capabilities / EPR_Source_Capabilities or Sink_Capabilities / EPR_Sink_Capabilities Message respectively. Fixed Supply, Variable Supply and Battery Supply Power Data Objects are defined; SPR Mode uses all four while EPR Mode uses only Fixed Supply and AVS PDOs. Power Delivery Mode Operation after a Contract has initially been established between a Port Pair. This Mode persists during normal Power Delivery operation, including after a Power Delivery Mode. Power Delivery Mode can only be exited by Detaching the Ports, applying a Hard Reset or by the Source removing power (except when the Initial Source removes power from VBUS during the Power Role Swap procedure). Power Provider See Provider. Power Role A Port Partner will be in one of two Power Roles; either Source or Sink. Power Role Swap Process of exchanging the Source and Sink Power Roles between Port Partners. Power Rules Define voltages and current ranges that are offered by compliant USB Power Delivery Sources and used by a USB Power Delivery Sink for a given value of PDP Rating. See Section 10, "Power Rules". PPS See Programmable Power Supply. PPS Mode An SPR Source, currently operating as an PPS, is said to be operating in PPS Mode. Preamble Start of a transmission which is used to enable the receiver to lock onto the carrier. The Preamble consists of a 64-bit sequence of alternating 0s and 1s starting with a "0" and ending with a "1" which is not 4b5b encoded. Product Type Product categorization returned as part of the Discover Identity Command. Product Type VDO VDO identifying a certain Product Type in the ID Header VDO of a Discover Identity Command. Product VDO The Product VDO contains identity information relating to the product. Programmable Power Supply A power supply, operating in SPR Mode, whose output voltage can be programmatically adjusted in small increments over its Advertised range and has a programmable output current fold back (note that the SPR AVS and EPR AVS does not).The Capabilities are exposed by the SPR Programmable Power Supply APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). Protocol Error An unexpected Message during an Atomic Message Sequence. A Protocol Error during an AMS will result in either a Soft Reset or a Hard Reset. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 48 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Layer The entity that forms the Messages used to communicate information between Port Partners. Provider A PD Port (typically a USB Host, Hub, or Charger DFP) that can source power over the power conductor (e.g., VBUS). This corresponds to a USB Type-C Port with Rp asserted on its CC wire. Provider/Consumer A Provider with the additional capability to act as a Consumer. This corresponds to a Dual-Role Power Port with Rp asserted on its CC wire. PS1 PS2 PS3 Classification of electrical power as defined in [IEC 62368-1]. PSD Sink which draws power but has no other USB or Alternate Mode communication function e.g., a power bank. Ra Prior to application of VCONN, a powered cable applies a pull-down resistor Ra on its VCONN pin. Rd Pull-down resistor on the USB Type-C CC wire used to indicate that the Port is a Sink (see [USB Type-C 2.4]). RDO See Request Data Object. Re-attach Attach of the Port Pair by a cable after a previous Detach. Re-negotiate See Re-negotiation. Re-negotiated See Re-negotiation. Re-negotiation A process wherein one of the Port Partners wants to alter the Negotiated Contract. Request Message used by a Sink Port to Negotiate a Contract; refers to either a Request/EPR_Request Message. Request Data Object Data Object used by a Sink Port to Negotiate a Contract as a part of a Request/EPR_Request Message. Responder The receiver of a Command request sent by an Initiator that replies with a Command response. Revision Major release of the USB Power Delivery specification. Each Revision will have variousVersions associated with it. Revision 1.0 Deprecated major Revision of the USB Power Delivery Specification. Revision 2.0 Superseded major Revision of the USB Power Delivery Specification as defined in [USBPD 2.0], with which this specification is compatible. Revision 3.x Current major Revisions of the USB Power Delivery Specification. Rp Pull-up resistor on the USB Type-C CC wire used to indicate that the Port is a Source (see [USB Type-C 2.4]). Safe Operation Sources must have the ability to tolerate vSafe5V applied by both Port Partners. Shared Capacity Charger As defined in [USB Type-C 2.4]. This maps to a Charger with multiple Managed Capability Ports. Shared Capacity Group As defined in [USB Type-C 2.4]. This maps to a group with Managed Capability Ports. SID See Standard ID. Signaling A Preamble followed by an ordered set of four K-codes used to indicate a particular line symbol e.g., Hard Reset as defined in Section 5.4, "Ordered Sets". Signaling Scheme Physical mechanism used to transmit bits. Only the BMC Signaling Scheme is defined in this specification. Note: The BFSK Signaling Scheme supported in Revision 1.0 of this specification has been Deprecated. Single-Role Port A Port that is only capable of operating either as a Source or Sink, but not both. E.g., the port is not a DRP. Sink The Port consuming power from VBUS; most commonly a USB Device. Sink Capabilities Capabilities wanted by a Sink. Sink Directed Charge A charging scheme whereby the Sink connects the Source to its Battery through safety and other circuitry. When the SPR PPS Current Limit feature is activated, the Source automatically controls its output current by adjusting its output voltage. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 49 Sink Port Port operating as a Sink. Sink Standby During Sink Standby the Sink reduces its current draw to iSnkStdby Soft Reset A process that resets the PD communications engine to its default state. SOP K-code marker used for communication between Port Partners. See also Start of Packet. SOP Communication Communication using SOP Packets also implies that an AMS is being followed. SOP Packet Any Power Delivery Packet which starts with an SOP. SOP’ Communication Communication with a Cable Plug using SOP’ Packets, also implies that an AMS is being followed. SOP’ Packet Any Power Delivery Packet which starts with an SOP’ used to communicate with a Cable Plug. SOP’’ Communication Communication with a Cable Plug using SOP’’ Packets, also implies that an AMS is being followed. SOP’’ Packet Any Power Delivery Packet which starts with an SOP’’ used to communicate with a Cable Plug when SOP’ Packets are being used to communicate with the other Cable Plug. SOP’ SOP’’ K-code marker used for communication between a Port and a Cable Plug. See also Start of Packet. SOP* Used to generically refer to K-code markers: SOP, SOP’ and SOP’’. See also Start of Packet. SOP* Communication Communication using SOP* Packets, also implies an AMS is being followed. SOP* Packet A term referring to any Power Delivery Packet starting with either SOP, SOP’, or SOP’’. Source The Power Role a Port is operating in to supply power over VBUS; most commonly a USB Host or Hub downstream port. Source Capabilities Capabilities offered by a Source. Source Port Port operating as a Source. Specification Revision See Revision. SPM See System Policy Manager. SPR See Standard Power Range. SPR AVS An SPR Source whose output voltage can be adjusted to an operating voltage within its Advertised range. Unlike SPR PPS, it does not support current limit. The SPR AVS Capabilities are exposed by the SPR AVS APDO (see Section 6.4.1.2.4.2, "SPR Adjustable Voltage Supply APDO"). SPR AVS Mode A SPR Source, currently operating in an SPR AVS Contract, is said to be operating in SPR AVS Mode. SPR Capabilities An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) has at least one Power Data Object for vSafe5V followed by up to 6 additional Power Data Objects. SPR Contract Explicit Contract Negotiated, in SPR Mode, based on SPR (A)PDOs. SPR Mode The classic mode of PD operation where Explicit Contracts are Negotiated using SPR (A)PDOs. SPR (A)PDO Fixed Supply PDO that offers up to 20V and no more than 100W. Variable Supply PDO whose Maximum voltage offers up to 21V and no more than 100W. Battery Supply PDO whose Maximum voltage offers up to 21V and no more than 100W. Adjustable Voltage Supply (AVS) APDO whose Maximum voltage is up to 20V and no more than 100W. Programmable Power Supply (PPS) APDO whose Maximum voltage is up to 21V and no more than 100W. SPR PPS A power supply whose output voltage and output current can be programmatically adjusted in small increments over its Advertised range. It supports current limit unlike SPR AVS and EPR AVS. The Capabilities are exposed by the Programmable Power Supply APDOs (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). SPR PPS Mode A power supply, currently operating in an SPR PPS Contract, is said to be operating in SPR PPS Mode. SPR Sink A Sink which only supports SPR Mode and does not support EPR Mode. SPR Sink Port A Port exposed on an SPR Sink. SPR Source A Source which only supports SPR Mode and does not support EPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 50 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SPR Source Port A Port exposed on an SPR Source. Standard ID 16-bit unsigned value assigned by the USB-IF to a given industry standards organization’s specification. Standard or Vendor ID Generic term referring to either a VID or a SID. SVID is used in place of the phrase “Standard or Vendor ID.” Standard Power Range Only the Source_Capabilities and the Request Messages are allowed to Negotiate SPR Explicit Contracts. The EPR Messages (the EPR_Source_Capabilities Message and the EPR_Request Message) are not allowed to be used while in SPR Mode. Start of Packet K-code marker used to delineate the start of a Packet. State PD state machine state as defined in Section 6.12, "State behavior" and Section 8.3.3, "State Diagrams" state machines. Structured VDM See Structured Vendor Defined Message. Structured VDM Header The VDM Header for a Structured Vendor Defined Message. Structured Vendor Defined Message A Vendor Defined Message where the contents and usage of bits 14...0 of the VDM Header are defined by this specification. SVDM See Structured Vendor Defined Message. SVID See Standard or Vendor ID. Swap Standby During Swap Standby the Source does not drive VBUS and the Sink's current draw does not exceed iSnkSwapStdby. System Policy Overall system Policy generated by the system, broken up into the policies required by each Port Pair to affect the System Policy. It is programmatically fed to the individual devices for consumption by their Policy Engines. System Policy Manager Module running on the USB Host. It applies the System Policy through communication with PD Capable Consumers and Providers that are also connected to the USB Host via USB. Test Frame Frame consisting of a Preamble, SOP*, followed by test data (See Section 5.9, "Built in Self-Test (BIST)"). Test Pattern Continuous stream of test data in a given sequence (See Section 5.9, "Built in Self-Test (BIST)"). Tester The Tester is assumed to be a piece of test equipment that manages the BIST testing process of a PD UUT. UFP See Upstream Facing Port. UFP VDO VDO returned by the UFP containing Capabilities. UI See Unit Interval. Unchunked See Unchunked Extended Message. Unchunked Extended Message Extended Message that has been transmitted whole without using Chunking. Unexpected Message Message that a Port supports but has been received in an incorrect State. Unit Interval The time to transmit a single data bit on the wire. Unit Under Test The PD device that is being tested by the Tester and responds to the initiation of a particular BIST test sequence. Unrecognized Message Message that a Port does not understand e.g., a Message using a Reserved Message type, a Message defined by a higher specification Revision than the Revision this Port supports, or an Unstructured Vendor Defined Message for which the VID is not recognized. Unstructured VDM See Unstructured Vendor Defined Message. Unstructured VDM Header The VDM Header for an Unstructured Vendor Defined Message. Unstructured Vendor Defined Message A Vendor Defined Message where the contents of bits 14...0 of the VDM Header are undefined. Unsupported Message Message that a Port recognizes but does not support. This is a Message defined by the specification, but which is not supported by this Port. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 51 Upstream Facing Port Indicates the Port’s position in the USB topology typically a Port on a Device as defined in [USB Type-C 2.4]. At connection, the Port defaults to operation as a USB Device (when USB Communication is supported) and Sink. USB Attached State Synonymous with the [USB 2.0] and [USB 3.2] definition of the Attached state USB Communication Transfer of USB data Packets as defined in [USB 2.0] and [USB 3.2]. USB Default Operation Operation of a Port at Attach or after a Hard Reset where the DFP Source applies vSafe5V on VBUS and the UFP Sink is operating at vSafe5V as defined in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2]. USB Device Either a Hub or a Peripheral device as defined in [USB 2.0], [USB 3.2] and [USB4]. USB Host The computer system where the USB Host controller is installed as defined in [USB 2.0], [USB 3.2] and [USB4]. USB Hub See Hub. USB Powered State Synonymous with the [USB 2.0] and [USB 3.2] definition of the powered state. USB Safe State State of the USB Type-C connector when there are pins to be re-purposed (see [USB Type-C 2.4]) so they are not damaged by and do not cause damage to their Port Partner. USB Type-A Term used to refer to any A plug or receptacle including USB Micro-A plugs and USB Standard- A plugs and receptacles. USB Micro-AB receptacles are assumed to be a combination of USB Type-A and USB Type-B. USB Type-B Terms used to refer to any B-plug or receptacle including USB Micro-B plugs and USB Standard- B plugs and receptacles, including the PD and non-PD versions. USB Micro-AB receptacles are assumed to be a combination of USB Type-A and USB Type-B. USB Type-C Term used to refer to the USB Type-C connector plug, or receptacle as defined in [USB Type-C 2.4]. USB Type-C Multi-Port Charger A product that exposes multiple USB Type-C Source Ports for the purpose of charging multiple connected USB Devices as defined in [USB Type-C 2.4]. USB-C® Port Control Module in a PD Capable device which controls Attach/Detach and either detects or sets the Rp value. USB-IF PD SID Standard ID allocated to this specification by the USB Implementer’s Forum. USB4® Mode Device is operating in a Mode as defined in [USB4]. UUT See Unit Under Test. Variable Supply A poorly regulated power supply that is not a Battery. This is exposed by the Variable Supply PDO (see Section 6.4.2, "Request Message"). VBUS The VBUS wire delivers power from a Source to a Sink. VCONN Once the connection between USB Host and device is established, the CC pin (CC1 or CC2) in the receptacle that is not connected via the CC wire through the standard cable is re-purposed to source VCONN to power circuits in a Cable Plug, VCONN Powered Accessory or VCONN Powered USB Device (see [USB Type-C 2.4]). VCONN Powered Accessory An accessory that is powered from VCONN to operate in an Alternate Mode (see [USB Type-C 2.4]). VCONN Powered USB Charge Through Device A CT-VPD is a VPD with an additional port for connecting a Source (e.g., a Charger) as defined in [USB Type-C 2.4]. When no Charger is connected, a CT-VPD behaves as a VPD. When a Charger is connected, no PD communication to the CT-VPD itself is possible as CC is connected to the Charger port. Hence all PD communication then is with the Charger and the cable with which it is connected. Table 1.4 Terms and Abbreviations (Continued) Term Description
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Page 52 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.7 Parameter Values The parameters in this specification are expressed in terms of absolute values. For details of how each parameter is measured in compliance please see [USBPDCompliance]. 1.8 Changes from Revision 3.0 Extended Power Range (EPR) including Adjustable Voltage Supply (AVS) has been added. 1.9 Compatibility with Revision 2.0 This Revision of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware. Please see Section 2.3, "USB Power Delivery Capable Devices" for more details of the mechanisms defined to enable compatibility. VCONN Powered USB Device A captive cable USB Device that can be powered by either VCONN or VBUS as defined in [USB Type- C 2.4]. A VPD is a captive cable USB Device that can be powered by either VCONN or VBUS and only responds to SOP’ Communication as defined in the Tables in Section 6.12, "State behavior"). It only responds to Messages sent with a Specification Revision of at least Revision 3.x. A VPD is not allowed to support Alternate Modes. The term VPD refers to either a VPD or a CT-VPD with no Charger connected. VCONN Source The USB Type-C Port responsible for sourcing VCONN. VCONN Swap Process of exchanging the VCONN Source between Port Partners. VDEM See Vendor Defined Extended Message. VDM See Vendor Defined Message. VDM Header The first Data Object following the Message Header in a Vendor Defined Message. The VDM Header contains the SVID relating to the VDM being sent and provides information relating to the Command in the case of a Structured VDM (see Section 6.4.4, "Vendor Defined Message"). VDO See Vendor Data Object. Vendor Data Object Data Object used to send Vendor specific information as part of a Message. Vendor Defined Extended Message PD Extended Message defined for vendor/standards usage. A VDEM does not define any structure and Messages can be created in any manner that the vendor chooses. Vendor Defined Message PD Data Message defined for vendor/standards usage. These are further partitioned into Structured Vendor Defined Messages, where Commands are defined in this specification, and Unstructured Vendor Defined Messages which are entirely vendor defined (see Section 6.4.4, "Vendor Defined Message"). Vendor ID 16-bit unsigned value assigned by the USB-IF to a given Vendor. Version A minor release of the USB Power Delivery specification associated with a particular Revision. Version numbers are also defined in VDMs. VI Same as power (i.e., voltage * current = power) VID See Vendor ID. VPD See VCONN Powered USB Device. Table 1.4 Terms and Abbreviations (Continued) Term Description
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Page 52 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.7 Parameter Values The parameters in this specification are expressed in terms of absolute values. For details of how each parameter is measured in compliance please see [USBPDCompliance]. 1.8 Changes from Revision 3.0 Extended Power Range (EPR) including Adjustable Voltage Supply (AVS) has been added. 1.9 Compatibility with Revision 2.0 This Revision of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware. Please see Section 2.3, "USB Power Delivery Capable Devices" for more details of the mechanisms defined to enable compatibility. VCONN Powered USB Device A captive cable USB Device that can be powered by either VCONN or VBUS as defined in [USB Type- C 2.4]. A VPD is a captive cable USB Device that can be powered by either VCONN or VBUS and only responds to SOP’ Communication as defined in the Tables in Section 6.12, "State behavior"). It only responds to Messages sent with a Specification Revision of at least Revision 3.x. A VPD is not allowed to support Alternate Modes. The term VPD refers to either a VPD or a CT-VPD with no Charger connected. VCONN Source The USB Type-C Port responsible for sourcing VCONN. VCONN Swap Process of exchanging the VCONN Source between Port Partners. VDEM See Vendor Defined Extended Message. VDM See Vendor Defined Message. VDM Header The first Data Object following the Message Header in a Vendor Defined Message. The VDM Header contains the SVID relating to the VDM being sent and provides information relating to the Command in the case of a Structured VDM (see Section 6.4.4, "Vendor Defined Message"). VDO See Vendor Data Object. Vendor Data Object Data Object used to send Vendor specific information as part of a Message. Vendor Defined Extended Message PD Extended Message defined for vendor/standards usage. A VDEM does not define any structure and Messages can be created in any manner that the vendor chooses. Vendor Defined Message PD Data Message defined for vendor/standards usage. These are further partitioned into Structured Vendor Defined Messages, where Commands are defined in this specification, and Unstructured Vendor Defined Messages which are entirely vendor defined (see Section 6.4.4, "Vendor Defined Message"). Vendor ID 16-bit unsigned value assigned by the USB-IF to a given Vendor. Version A minor release of the USB Power Delivery specification associated with a particular Revision. Version numbers are also defined in VDMs. VI Same as power (i.e., voltage * current = power) VID See Vendor ID. VPD See VCONN Powered USB Device. Table 1.4 Terms and Abbreviations (Continued) Term Description
1.9 - Compatibility with Revision 2.0.............................................................................................. (Page 52)
Page 52 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.7 Parameter Values The parameters in this specification are expressed in terms of absolute values. For details of how each parameter is measured in compliance please see [USBPDCompliance]. 1.8 Changes from Revision 3.0 Extended Power Range (EPR) including Adjustable Voltage Supply (AVS) has been added. 1.9 Compatibility with Revision 2.0 This Revision of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware. Please see Section 2.3, "USB Power Delivery Capable Devices" for more details of the mechanisms defined to enable compatibility. VCONN Powered USB Device A captive cable USB Device that can be powered by either VCONN or VBUS as defined in [USB Type- C 2.4]. A VPD is a captive cable USB Device that can be powered by either VCONN or VBUS and only responds to SOP’ Communication as defined in the Tables in Section 6.12, "State behavior"). It only responds to Messages sent with a Specification Revision of at least Revision 3.x. A VPD is not allowed to support Alternate Modes. The term VPD refers to either a VPD or a CT-VPD with no Charger connected. VCONN Source The USB Type-C Port responsible for sourcing VCONN. VCONN Swap Process of exchanging the VCONN Source between Port Partners. VDEM See Vendor Defined Extended Message. VDM See Vendor Defined Message. VDM Header The first Data Object following the Message Header in a Vendor Defined Message. The VDM Header contains the SVID relating to the VDM being sent and provides information relating to the Command in the case of a Structured VDM (see Section 6.4.4, "Vendor Defined Message"). VDO See Vendor Data Object. Vendor Data Object Data Object used to send Vendor specific information as part of a Message. Vendor Defined Extended Message PD Extended Message defined for vendor/standards usage. A VDEM does not define any structure and Messages can be created in any manner that the vendor chooses. Vendor Defined Message PD Data Message defined for vendor/standards usage. These are further partitioned into Structured Vendor Defined Messages, where Commands are defined in this specification, and Unstructured Vendor Defined Messages which are entirely vendor defined (see Section 6.4.4, "Vendor Defined Message"). Vendor ID 16-bit unsigned value assigned by the USB-IF to a given Vendor. Version A minor release of the USB Power Delivery specification associated with a particular Revision. Version numbers are also defined in VDMs. VI Same as power (i.e., voltage * current = power) VID See Vendor ID. VPD See VCONN Powered USB Device. Table 1.4 Terms and Abbreviations (Continued) Term Description
2.1 - Introduction..................................................................................................................................... (Page 53)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 53 2 Overview This section contains no Normative requirements. 2.1 Introduction USB Power Delivery (PD) defines the mechanisms for pairs of directly Attached Ports (also referred to as Port Partners or Port Pairs) to Negotiate voltage, current and/or direction of power flow over the USB cable. It uses the USB Type-C® connector's CC wire as the communications channel. The PD mechanisms operate independently of and supersede other USB methods defined in [USB 2.0], [USB 3.2], [USBBC 1.2] and [USB Type-C 2.4]. USB Power Delivery also defines sideband mechanisms used for configuration management of USB Type-C devices and cables. Using Structured Vendor Defined Messages (Structured VDMs), PD facilitates discovery of device and cables features and performance. Structured VDMs are also used to enter/exit some Active Modes, either USB-based (e.g., USB4® Mode) or USB Type-C Alternate Modes. Alternate Modes are associated with Standard or Vendor IDs (SVIDs) and can be either standard (e.g., DisplayPort Alternate Mode) or proprietary (e.g., Intel Thunderbolt™ 3). 2.1.1 Power Delivery Source Operational Contracts A PD Source will be in one of three Contracts:  Default Contract which it enters immediately following a Connect where the Source provides 5V and Advertises the amount of current it can deliver using the Rp value as defined in [USB Type-C 2.4]. A Source in a Default Contract will remain in this Contract until the Sink is Detached or the Source and Sink Negotiate and enter an Explicit Contract.  Implicit Contract which immediately follows a Power Role Swap or Fast Role Swap and is transitory. The PD Source provides 5V and Advertises the amount of current it can deliver using the Rp value as defined in [USB Type-C 2.4]. A Source in an Implicit Contract will immediately Negotiate with the Sink and enter an Explicit Contract.  Explicit Contract is the state of the Source after any PD power Negotiation consisting of the Source sending a Source_Capabilities Message, the Sink responding with a Request Message, the Source acknowledging the request with an Accept Message and finally the Source sends a PS_RDY Message when the Source is ready to deliver the requested power. This is the normal operational state for PD. A Source in an Explicit Contract will remain in an Explicit Contract during and after a Re-negotiation of its Contract and will exit the Explicit Contract when:  Disconnected from the Sink where it will restart in a Default Contract when reconnected to the Sink.  Following a Hard Reset where it will restart as if it were Detached then Attached to the Sink.  Following a Power Role Swap or Fast Role Swap where it will enter an Implicit Contract.  Following USB Type-C Error Recovery which is an electrical Detach/Re-attach (remove and assert Rp). 2.1.2 Power Delivery Contract Negotiation Contracts Negotiated using the USB Power Delivery Specification supersede any and all previous power contracts established whether from standard [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] mechanisms. While operating in Power Delivery Mode there will be a Contract in place (either Explicit Contract or Implicit Contract) that determines the power level available and the direction of that power. The Port Pair will remain in Power Delivery Mode until the Port Pair is Detached, there is a Hard Reset, or USB Type-C Error Recovery, or the Source removes power except as part of the Power Role Swap or Fast Role Swap processes. Note: [USB4] does not define a default power, rather relies on a PD power Contract. When first Attached the [USB4] device operates in [USB 3.2] Mode which is its USB Default Operation. An Explicit Contract is Negotiated by the process of the Source sending a set of Capabilities, from which the Sink is required to request a particular capability and then the Source accepting this request.
2.2 - Compatibility with Revision 2.0.............................................................................................. (Page 54)
Page 54 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 An Implicit Contract is the specified level of power allowed in particular states (i.e., during and after a Power Role Swap or Fast Role Swap). Implicit Contracts are temporary; Port Pairs are required to immediately Negotiate an Explicit Contract. Each Provider has a Local Policy, governing power allocation to its Ports. Consumers also have their own Local Policy governing how they draw power. A System Policy can be enacted over USB that allows modification to this Local Policy and hence management of overall power allocation in the system. When PD Capable devices are Attached to each other, the DFPs and UFPs initially default to standard USB Default Operation. The DFP supplies vSafe5V and the UFP draws current in accordance with the rules defined by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] specifications. After Power Delivery Negotiation has taken place, power can be supplied at higher, or lower, voltages and higher currents than defined in these specifications. It is also possible to:  Do a Power Role Swap or Fast Role Swap to exchange the Power Roles such that the DFP receives power and the UFP supplies power.  Do a Data Role Swap such that the DFP becomes the UFP and vice-versa.  Do a VCONN Swap to change the Port supplying VCONN to the cable.  Enter into EPR Mode.  Enter into USB4® Mode.  Enter into Alternate Modes.  Send Vendor Defined Messages. Prior to the First Explicit Contract only the Source Port, which is also the VCONN Source, can communicate with the Attached cable assembly. This is important where 5A and EPR capability are marked as well as other details of the cable assembly such as the supported speed. Cable Discovery, determining whether the cable can communicate, can occur on initial Attachment of a Port Pair before an Explicit Contract has been established. It is also possible to carry out Cable Discovery after a Power Role Swap or Fast Role Swap prior to re-establishing an Explicit Contract, where the UFP is the Source, and an Implicit Contract is in place. Cable Discovery can be carried out after an Explicit Contract has been established, if the cable has not yet been discovered. 2.1.3 Other Uses for Power Delivery Once an Explicit Contract is in place, PD can be used to manage the Ports and cables for non-power related functionality. PD is used to enter the USB4® Mode of operation. Ports and cables can support functionality beyond power. For example, a cable can have active components that require VCONN power or a Port/cable can support a video display Alternate Mode such as DisplayPort. PD defines an infrastructure to discover these additional Capabilities and Modes that include:  Discovering a Port or Cable Plug's Capabilities.  Discovery of the SVIDs a Port or Cable Plug supports.  Discovery of the Modes a Port or Cable Plug supports.  Entry into a Mode supported by the Port and/or Cable Plug.  Exiting Modes supported by the Port and/or Cable Plug. 2.2 Compatibility with Revision 2.0 Revision 3.x of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware.
2.3 - USB Power Delivery Capable Devices................................................................................... (Page 55)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 55 This specification mandates that all Revision 3.x systems fully support Revision 2.0 operation. They must discover the supported Revision used by their Port Partner and any connected Cable Plugs and revert to operation using the lowest common Revision number (see Section 6.2.1.1.5, "Specification Revision"). This specification defines Extended Messages containing data of up to 260 bytes (see Section 6.2.1.2, "Extended Message Header"). These Messages can be larger than expected by existing PHY HW. To accommodate Revision 2.0 based systems a Chunking mechanism is mandated such that Messages are limited to Revision 2.0 sizes unless it is discovered that both systems support the longer Message lengths. This specification includes changes to the Vendor Data Objects (VDO) used in the discovery of passive/active marked cables and Alternate Mode Adapters (AMA) (see Section 6.4.4.2, "Structured VDM"). To enable systems to determine which VDO format is being used the Structured Vendor Defined Message (SVDM) Version number has been incremented to 2.x. Version numbers have also been incorporated into the VDOs themselves to facilitate future changes if these become necessary. 2.3 USB Power Delivery Capable Devices Some examples of USB Power Delivery capable devices can be seen in Figure 2.1, "Logical Structure of USB Power Delivery Capable Devices" (a USB Host, a USB Device, a Hub, and a Charger). These are given for reference only and are not intended to limit the possible configurations of products that can be built using this specification. Figure 2.1 Logical Structure of USB Power Delivery Capable Devices Each USB Power Delivery capable device is assumed to be made up of at least one Port. Providers are assumed to have a Source and Consumers a Sink. Each device contains one, or more, of the following components:  UFPs that:  Sink Power.  Communicate using SOP Packets.  Optionally Communicate using SOP’ Packets/SOP’’ Packets.  Optionally source power (a Dual-Role Power Device).  Optionally communicate via USB.  Optionally support Alternate Modes.  DFPs that: USB Host UFP USB Device Power Storage External power USB Hub DFP Power Storage External power USB Charger UFP Power Storage External power External power Power Storage DFP DFP Optional Power input Optional Feature Multiple Power inputs/outputs Multiple Power outputs Power input Legend Page 56 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Source Power  Communicate using SOP Packets.  Optionally Communicate using SOP* Packets.  Optionally Sink power (a Dual-Role Power Device).  Optionally communicate via USB.  Optionally support Alternate Modes.  A Source that can be:  An externally powered source (e.g., AC powered).  Power Storage (e.g., Battery/Power Bank).  Derived from another Port (e.g., bus-powered Hub).  A Sink that can be:  Power Storage (e.g., a Battery/Power Bank).  Used to power internal functions.  Used to power devices Attached to other devices (e.g., a bus-powered Hub).  A VCONN Source that:  Can be either Port Partner, either the DFP/UFP or Source/Sink.  Powers the Cable Plug(s).  Powers VPDs (VCONN Powered USB Devices).  Is the only Port allowed to talk to the Cable Plug(s) at any given time.
2.4 - SOP* Communication................................................................................................................... (Page 57)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 57 2.4 SOP* Communication 2.4.1 Introduction The Start of Packet (or SOP) is used as an addressing scheme to identify whether the communications were intended for one of the Port Partners (SOP Communication) or one of the Cable Plugs (SOP’ Communication/SOP’’ Communication). SOP/SOP’ and SOP’’ are collectively referred to as SOP*. All SOP* Communications take place over a single wire (CC). The term Cable Plug in the SOP’ Communication/SOP’’ Communication case is used to represent a logical entity in the cable which is capable of PD Communication, and which might or might not be physically located in the plug. Note: There are there are other SOPs defined for special operation such as debug which are not discussed here. The following sections describe how this addressing scheme operates for Port-to-Port and Port to Cable Plug communication. 2.4.2 SOP* Collision Avoidance For all SOP* the Source co-ordinates communication to avoid bus collisions by allowing the Sink to initiate messaging when it does not need to communicate itself. Once an Explicit Contract is in place, the Source manipulates its Rp value (3A) to indicate to the Sink that it can initiate an Atomic Message Sequence (AMS). This AMS can be communication with the Source or with one of the Cable Plugs. As soon as the Source itself needs to initiate an AMS, it will manipulate its Rp value (1.5A) to indicate this to the Sink. The Source then waits for any outstanding Sink SOP* Communication to complete before initiating an AMS itself. In all cases, the Port initiating an AMS waits for CC to be Idle before putting the Message on CC. 2.4.3 SOP Communication SOP Communication is used for Port-to-Port communication between the Source and the Sink. SOP Communication is recognized by both Port Partners but not by any intervening Cable Plugs. SOP Communication takes priority over other SOP* Communications since it is critical to complete power related operations as soon as possible. 2.4.4 SOP'/SOP'' Communication with Cable Plugs SOP’ Communication is recognized by electronics in one Cable Plug (see [USB Type-C 2.4]). SOP’’ Communication can also be supported when SOP’ Communication is also supported. SOP’ and SOP’’ assignment in the cable assembly is fixed and does not change dynamically. SOP Communication between the Port Partners is not recognized by the Cable Plug. Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)" outlines the usage of SOP* Communications between a VCONN Source (DFP/UFP) and the Cable Plugs. Since all SOP* Communications take place over a single wire (CC), the SOP* Communication periods must be coordinated to prevent important communication from being blocked. For a product which does not recognize SOP/SOP’ or SOP’’ Packets, this will look like a non-Idle channel, leading to missed Packets and retries. Communications between the Port Partners take precedence meaning that communications with the Cable Plug can be interrupted but will not lead to a Soft Reset or Hard Reset. When a Default Contract or Implicit Contract is in place (e.g., at startup, after a Power Role Swap or Fast Role Swap) only the Source Port that is supplying VCONN is allowed to send Packets to a Cable Plug (SOP’) and is allowed to respond to Packets from the Cable Plug (SOP’) with a GoodCRC Message in order to discover the Cable Plug's characteristics (see Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)"). During this phase, all communication with the Cable Plug is initiated and controlled by the VCONN Source which acts to prevent conflicts between SOP Packets and SOP’ Packets. The Sink does not communicate with the Cable Plug and Discards any SOP’ Packets received. When an Explicit Contract is in place, only the VCONN Source (either the DFP or the UFP) can communicate with the Cable Plug(s) using SOP’ Packets/SOP’’ Packets (see Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)"). During this phase, all communication with the Cable Plug is initiated and controlled by the VCONN Source which acts to prevent conflicts between SOP* Packets. The Port that is not the VCONN Source is not Page 58 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 allowed to communicate with the Cable Plug and does not recognize any SOP’ Packets/SOP’’ Packets received. Only the DFP, when acting as a VCONN Source, is allowed to send SOP* Packets to control the entry and exiting of Modes and to manage Modal Operation. Figure 2.2 Example SOP' Communication between VCONN Source and Cable Plug(s) VCONN Source (DFP/UFP) SOP signaling SOP’ signaling SOP’’ signaling Cable Plug1 (SOP’’) Electronically Marked Cable Cable Plug1 (SOP’) VCONN
2.5 - Operational Overview.................................................................................................................. (Page 59)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 59 2.5 Operational Overview A USB Power Delivery Port supplying power is known as a Source and a Port consuming power is known as a Sink. There is only one Source Port and one Sink Port in each PD Connection between the Port Partners. At Attach the Source Port (the Port with Rp asserted see [USB Type-C 2.4]) is also the DFP and VCONN Source. At Attach the Sink Port (the Port with Rd asserted) is also the UFP and is not the VCONN Source. The original USB PD specification allowed Sources to deliver up to 100W. This classic Mode of operation is referred to as the Standard Power Range (SPR). The First Explicit Contract, the first Contract after a Default Contract or Implicit Contract, is always an SPR Contract. There is an Optional higher power Mode referred to as the Extended Power Range (EPR) where the Source is allowed to deliver up to 240W. The EPR Mode can only be entered from the SPR Mode. The entry process is designed to prevent accidental entry into this higher power Mode. It can be entered only when an SPR Explicit Contract is in place and both the Source Port and Sink Port as well as the cable support EPR. The Source/Sink Power Roles, DFP/UFP Data Roles and VCONN Source role can all subsequently be swapped orthogonally to each other. A Port that supports both Source and Sink Power Roles is called a Dual-Role Power Port (DRP). A Port that supports both DFP and UFP Data Roles is called a Dual-Role Data Port (DRD). When USB Communications capability is supported in the DFP Data Role then the Port will also be able to act as a USB Host. Similarly, when USB Communications capability is supported in the UFP Data Role then the Port will also be able to act as a USB Device. The following sections describe the high-level operation of ports taking on the roles of DFP, UFP, Source and Sink. For details of how PD maps to USB states in a PDUSB Device see Section 9.1.2, "Mapping to USB Device States". 2.5.1 Source Operation The Source operates differently depending on its Attachment status:  At Attach (no PD Connection or Contract):  For a Source-only Port the Source detects Sink Attachment.  For a DRP that toggles between Source and Sink operation, the Port becomes a Source Port on Attachment of a Sink  The Source then supplies vSafe5V.  Before PD Connection (no PD Connection or Contract):  Prior to sending Source_Capabilities Messages the Source can detect the Cable Capabilities and Advertises its Capabilities depending on the Cable Capabilities detected:  The default current carrying capability of a USB Type-C cable is 3A.  The Source can attempt to communicate with one of the Cable Plugs using SOP’ Packets. If the Cable Plug responds, then communication takes place to discover the cable's Capabilities (e.g., 5A capable).  The Source periodically Advertises its Capabilities by sending Source_Capabilities Messages every tTypeCSendSourceCap.  Establishing PD Connection (no PD Connection or Contract):  Presence of a PD Capable Port Partner is detected either:  By receiving a GoodCRC Message in response to a Source_Capabilities Message.  By receiving Hard Reset Signaling.  Establishing the First Explicit Contract after an Attach, Hard Reset, USB Type-C Error Recovery or Implicit Contract as a result of a Power Role Swap or Fast Role Swap: Page 60 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Source receives a Request Message from the Sink and, if this is a Valid request, responds with an Accept Message followed by a PS_RDY Message when its power supply is ready to source power at the agreed level. At this point an Explicit Contract has been agreed.  A DFP that does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  When in an Explicit Contract (PE_SRC_Ready State):  The Source processes and responds (if a response is required) to all Messages received and sends appropriate Messages whenever its Local Policy requires:  The Source informs the Sink whenever its Capabilities change, by sending a Source_Capabilities Message.  The Source responds to a Sink Request Message with the Capabilities mismatch bit set, by sending a Source_Capabilities Message with its maximum available power.  The Source will always have an Rp value asserted on its CC wire used for Collision Avoidance.  When this Port is a DRP the Source can initiate or receive a request for the exchange of Power Roles. After the Power Role Swap this Port will be a Sink and in an Implicit Contract until an Explicit Contract is Negotiated immediately afterwards.  When this Port is a DRD the Source can initiate or receive a request for an exchange of Data Roles. After a Data Role Swap the DFP (USB Host) becomes a UFP (USB Device). The Port remains a Source and the VCONN Source role remains unchanged.  The Source can initiate or receive a request for an exchange of VCONN Source role. During a VCONN Swap VCONN is applied by both Ports (make before break). The Port remains a Source and DFP/ UFP Data Roles remain unchanged.  The Source when it is the VCONN Source can communicate with a Cable Plug using SOP’ Communication or SOP’’ Communication at any time it is not engaged in any other SOP Communication:  If SOP Packets are received by the Source, during SOP’ Communication or SOP’’ Communication, the SOP’ Communication or SOP’’ Communication is immediately terminated (the Cable Plug times out and does not retry).  If the Source needs to initiate an SOP Communication during an ongoing SOP’ Communication or SOP’’ Communication (e.g., for a Capabilities change) then the SOP’ Communication or SOP’’ Communications will be interrupted.  When the Source Port is also a DFP:  The Source can control the entry and exiting of Modes in the Cable Plug(s) and control Modal Operation.  The Source can initiate Unstructured VDMs or Structured VDMs.  The Source can control the entry and exiting of Modes in the Sink and control Modal Operation using Structured VDMs.  Detach or communications failure:  A Source detects plug Detach and takes VBUS down to vSafe5V within tSafe5V and vSafe0V within tSafe0V (i.e. using USB Type-C Detach detection via CC).  When the Source detects the failure to receive a GoodCRC Message in response to a Message within tReceive:  Leads to a Soft Reset, within tSoftReset of the CRCReceiveTimer expiring. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 61  If the Soft Reset process cannot be completed a Hard Reset will be issued within tHardReset of the CRCReceiveTimer to restore VBUS to USB Default Operation within ~1-1.5s:  When the Source is also the VCONN Source, VCONN will also be power cycled during the Hard Reset.  When the Source operating in SPR PPS Mode fails to receive periodic communication (e.g., a Request Message) from the Sink within tPPSTimeout:  Source issues a Hard Reset and takes VBUS to vSafe5V.  When the Source operating in the EPR Mode fails to receive periodic communication (i.e., an EPR_KeepAlive Message or any other Message) from the Sink within tSourceEPRKeepAlive:  Source issues a Hard Reset and takes VBUS to vSafe5V.  Receiving no response to further attempts at communication is interpreted by the Source as an error (see Error handling).  Errors during power transitions will automatically lead to a Hard Reset to restore power to default levels.  Error handling:  Protocol Errors are handled by a Soft_Reset Message issued by either Port Partner, that resets counters, timers and states, but does not change the Negotiated voltage and current or the Port's role (e.g., Source, DFP/UFP, VCONN Source) and does not cause an exit from Modal Operation.  Serious errors are handled by Hard Reset Signaling issued by either Port Partner. A Hard Reset:  Resets protocol as for a Soft Reset but also returns the power supply to USB Default Operation (vSafe0V or vSafe5V output) in order to protect the Sink.  Restores the Port's Data Role to DFP.  Restores the Port's power to its USB default state.  When the Sink is the VCONN Source it removes VCONN then the Source Port is restored as the VCONN Source.  Causes all Active Modes to be exited such that the Source is no longer in Modal Operation.  After a Hard Reset it is expected that the Port Partner will respond within tNoResponse. If this does not occur then nHardResetCount further Hard Resets are carried out before the Source performs additional Error Recovery steps, as defined in [USB Type-C 2.4], by entering the ErrorRecovery state. Page 62 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.5.2 Sink Operation  At Attach (no PD Connection or Contract):  Sink detects Source Attachment through the presence of vSafe5V.  For a DRP that toggles between Source and Sink operation, the Port becomes a Sink Port on Attachment of a Source.  Once the Sink detects the presence of vSafe5V on VBUS it waits for a Source_Capabilities Message indicating the presence of a PD Capable Source.  If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap then it can issue Hard Reset Signaling in order to cause the Source Port to send a Source_Capabilities Message if the Source Port is PD Capable.  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  Establishing PD Connection (no PD Connection or Contract):  The Sink receives a Source_Capabilities Message and responds with a GoodCRC Message.  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  Establishing the First Explicit Contract after an Attach, Hard Reset or Implicit Contract as a result of a Power Role Swap or Fast Role Swap:  The Sink receives a Source_Capabilities Message from the Source and responds with a Request Message. If this is a Valid request the Sink receives an Accept Message followed by a PS_RDY Message when the Source's power supply is ready to source power at the agreed level. At this point the Source and Sink have entered into an Explicit Contract:  The Sink Port can request one of the Capabilities offered by the Source, even if this is the vSafe5V output offered by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2], in order to enable future power Negotiation:  A Sink not requesting any Valid capability with a Request Message results in an error.  A Sink unable to fully operate at the offered Capabilities requests the default capability but in- dicates that it would prefer another power level by setting the Capability Mismatch bit in the Request Message and also providing a physical indication of the failure to the end user (e.g., using an LED).  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  During PD Connection (Explicit Contract - PE_SNK_Ready state):  The Sink processes and responds (if a response is required) to all Messages received and sends appropriate Messages whenever its Local Policy requires.  A Sink whose power needs have changed indicates this to the Source with a new Request Message. The Sink Port can request one of the Capabilities previously offered by the Source, even if this is the vSafe5V output offered by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2], in order to enable future power Negotiation:  Not requesting any capability with a Request Message results in an error.  A Sink unable to fully operate at the offered Capabilities requests an offered capability but indicates a Capabilities Mismatch i.e., that it would prefer another power level also providing a physical indication of the failure to the end user (e.g., using an LED). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 63  A Sink operating in the SPR PPS Mode periodically sends Request Message within tPPSRequest even if its request is unchanged.  A Sink operating in the EPR Mode periodically communicates with the Source (i.e., sends an EPR_KeepAlive Message or any other Message) within tSourceEPRKeepAlive.  The Sink will always have Rd asserted on its CC wire.  When this Port is a DRP, the Sink can initiate or receive a request for the exchange of Power Roles. After the Power Role Swap this Port will be a Source and an Implicit Contract will be in place until an Explicit Contract is Negotiated immediately afterwards.  When this Port is a DRD the Sink can initiate or receive a request for an exchange of Data Roles. After a Data Role Swap the UFP (USB Device) becomes a DFP (USB Host). The Port remains a Sink and VCONN Source role (or not) remains unchanged.  The Sink can initiate or receive a request for an exchange of VCONN Source. During a VCONN Swap VCONN is applied by both ends (make before break). The Port remains a Sink and DFP/UFP Data Roles remain unchanged.  The Sink when it is the VCONN Source can communicate with a Cable Plug using SOP’ Communication or SOP’’ Communication at any time it is not engaged in any other SOP Communication:  If SOP Packets are received by the Sink, during SOP’ Communication or SOP’’ Communication, the SOP’ Communication or SOP’’ Communication is immediately terminated (the Cable Plug times out and does not retry)  If the Sink needs to initiate an SOP Communication during an ongoing SOP’ Communication or SOP’’ Communication (e.g., for a Capabilities change) then the SOP’ Communication or SOP’’ Communications will be interrupted.  When the Sink Port is also a DFP:  The Sink can initiate Unstructured VDMs or Structured VDMs.  The Sink can control the Mode Entry and Mode Exit of Modes in the Source and control Modal Operation (e.g. [USB4]).  Detach or Communications Failure:  A Sink detects the removal of VBUS and interprets this as the end of the PD Connection:  This is unless the vSafe0V is due to either a Hard Reset, Power Role Swap or Fast Role Swap.  A Sink detects plug removal (i.e., absence of Rp or VBUS) and discharges VBUS.  When the Sink detects the failure to receive a GoodCRC Message in response to a Message within tReceive:  Leads to a Soft Reset, within tSoftReset of the CRCReceiveTimer expiring.  If the Soft Reset process cannot be completed a Hard Reset will be issued within tHardReset of the CRCReceiveTimer to restore VBUS to USB Default Operation within ~1-1.5s.  Receiving no response to further attempts at communication is interpreted by the Sink as an error (see Error handling).  When the Sink operating in the SPR PPS Mode fails to send periodic communication (i.e. a Request Message) to the Source within tPPSRequest, the Source will issue a Hard Reset that results in VBUS going to vSafe5V.  When the Sink operating in the EPR Mode fails to send periodic communication (i.e. an EPR_KeepAlive Message or any other Message) to the Source within tSourceEPRKeepAlive the Source will issue a Hard Reset that results in VBUS going to vSafe5V. Page 64 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Errors during power transitions will automatically lead to a Hard Reset to restore power to default levels.  Error handling:  Protocol Errors are handled by a Soft_Reset Message issued by either Port Partner, that resets counters, timers and states, but does not change the Negotiate voltage and current or the Port's role (e.g., Sink, DFP/UFP, VCONN Source) and does not cause an exit from Modal Operation.  Serious errors are handled by Hard Reset Signaling issued by either Port Partner. A Hard Reset:  resets protocol as for a Soft Reset but also returns the power supply to USB Default Operation (vSafe0V or vSafe5V output) in order to protect the Sink.  restores the Port's Data Role to UFP.  when the Sink is the VCONN Source it removes VCONN then the Source Port is restored as the VCONN Source.  causes all Active Modes to be exited such that the Source is no longer in Modal Operation.  After a Hard Reset it is expected that the Port Partner will respond within tTypeCSinkWaitCap. If this does not occur, then two further Hard Resets are carried out before the UFP stays in the PE_SNK_Wait_for_Capabilities state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 65 2.5.3 Cable Plugs  Cable Plugs are powered when VCONN is present but are not aware of the status of the Contract between the ports the cable assembly is connecting.  Cable Plugs do not initiate AMSs and only respond to Messages sent to them.  Detach or Communications Failure:  Communications can be interrupted at any time.  There is no communication timeout scheme between the DFP/UFP and Cable Plug.  The Cable Plug is ready to respond to potentially repeated requests.  Error handling:  The Cable Plug detects Hard Reset Signaling to determine that the Source and Sink have been reset and will need to reset itself (equivalent to a power cycle).  The Cable Plug cannot generate Hard Reset Signaling itself.  The Hard Reset process power cycles both VBUS and VCONN so this is expected to reset the Cable Plugs by itself.  A Cable Plug detects Cable Reset Signaling to determine that it will need to reset itself (equivalent to a power cycle).
2.6 - Architectural Overview............................................................................................................... (Page 66)
Page 66 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.6 Architectural Overview This logical architecture is not intended to be taken as an implementation architecture. An implementation architecture is, by definition, a part of product definition and is therefore outside of the scope of this specification. This section outlines the high-level logical architecture of USB Power Delivery referenced throughout this specification. In practice various implementation options are possible based on many different possible types of PD devices. PD devices can have many different configurations e.g., USB Communication or non-USB Communication, single versus multiple Ports, dedicated power supplies versus supplies shared on multiple ports, hardware versus software-based implementations etc. The architecture outlined in this section is therefore provided only for reference to indicate the high-level logical model used by the PD specification. This architecture is used to identify the key concepts and to indicate logical blocks and possible links between them. The USB Power Delivery is a Port to Port architecture in which each PD Capable device is made up of several major components.  Figure 2.3, "USB Power Delivery Communications Stack" illustrates the relationship of the layers of the communications stack between a Port Pair. The communications stack consists of:  A Device Policy Manager (see Section 8.2, "Device Policy Manager") that exists in all devices and manages USB Power Delivery resources within the device across one or more Ports based on the device's Local Policy.  A Policy Engine (see Section 8.3, "Policy Engine") that exists in each USB Power Delivery Port implements the Local Policy for that Port.  A Protocol Layer (see Section 6, "Protocol Layer") that enables Messages to be exchanged between a Source Port and a Sink Port.  A PHY Layer (see Section 5, "Physical Layer") that handles transmission and reception of bits on the wire and handles data transmission Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 67 Figure 2.3 USB Power Delivery Communications Stack Additionally, USB Power Delivery devices which can operate as USB devices can communicate over USB (see Figure 2.4, "USB Power Delivery Communication Over USB"). An Optional System Policy Manager (see Chapter 9 and [UCSI]) that resides in the USB Host communicates with the PDUSB Device over USB, via the root Port and potentially manages the individual Port to Port connections over a tree of USB Hubs. The Device Policy Manager interacts with the USB interface in each device to provide and update PD related information in the USB domain. Note: A PD device is not required to have a USB device interface. Protocol Policy Engine Device Policy Manager CC Physical Layer Physical Layer Protocol Policy Engine Device Policy Manager Provider Consumer Page 68 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 2.4 USB Power Delivery Communication Over USB Figure 2.5, "High Level Architecture View" shows the logical blocks between two Attached PD Ports (Port Pair). In addition to the communication stack described above there are also:  For a Provider or Dual-Role Power Device: one or more Sources providing power to one or more Ports.  For a Consumer or Dual-Role Power Device: A Sink consuming power.  A USB-C® Port Control module (see Section4.4 "Cable Type Detection") that detects cable Attach/Detach as defined in [USB Type-C 2.4].  USB Power Delivery uses standard cabling as defined in [USB Type-C 2.4]. System Policy Manager Physical Layer Protocol Policy Engine Device Policy Manager CC PD USB Device USB Host USB Root Hub USB Interface USB Hub USB Hub Physical Layer Protocol Policy Engine Device Policy Manager CC PD USB Device USB Interface Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 69 The Device Policy Manager talks to the communication stack, Source/Sink, and the USB-C® Port Control block to manage the resources in the Provider or Consumer. Figure 2.5, "High Level Architecture View" illustrates a Provider and a Consumer. Dual-Role Power Devices can be constructed by combining the elements of both Provider and Consumer into a single device. Providers can also contain multiple Source Ports each with their own communications stack and USB-C® Port Control. Figure 2.5 High Level Architecture View 2.6.1 Policy There are two levels of Policy: 1) System Policy applied system wide by the System Policy Manager across multiple Providers or Consumers. 3) Local Policy enforced on a Provider or Consumer by the Device Policy Manager for a device. Policy comprises several logical blocks:  System Policy Manager (system wide).  Device Policy Manager (one per Provider or Consumer).  Policy Engine (one per Source Port or Sink Port). 2.6.1.1 System Policy Manager Since the USB Power Delivery protocol is Port to Port, implementation of a System Policy requires communication by an additional data communication mechanism i.e., USB. [UCSI]has been created to define an interface for the System Policy Manager to communicate with the Device Policy Manager. When present, the System Policy Manager monitors and controls System Policy between various Providers and Consumers connected via USB. The System Policy Manager resides in the USB Host and communicates via USB with the Device Policy Manager in each connected Device. Devices without USB Communication capability or are not data connected, will not be able to participate in System Policy. The System Policy Manager is Optional so USB Power Delivery Providers and Consumers will operate without it being present. This includes systems where the USB Host does not provide a System Policy Manager and can also include "headless" systems without any USB Host. In those cases where a USB Host is not present, USB Power Delivery is useful for charging purposes, or the powering of devices since useful USB functionality is not possible. Where there is a USB Host, but no System Policy Manager, Providers and Consumers can Negotiate power between Power Source(s) Physical Layer Protocol Source Port Device Policy Manager Provider Policy Engine Power Sink Physical Layer Protocol Sink Port Device Policy Manager Consumer Policy Engine USB-C Port Control USB-C Port Control VBUS USB Port VBUS USB Port CC CC BMC BMC CC VBUS Page 70 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 themselves, independently of USB power rules, but are more limited in terms of the options available for managing power. 2.6.1.2 Device Policy Manager The Device Policy Manager provides mechanisms to monitor and control the USB Power Delivery system within a particular Consumer or Provider. The Device Policy Manager enables Local Policy to be enforced across the system by communication with the System Policy Manager. Local Policy is enacted on a per Port basis by the Device Policy Manager's control of the Source Ports/Sink Ports and by communication with the Policy Engine and USB-C® Port Control for that Port. The Device Policy Manager is responsible for the sharing algorithm used in Shared Capacity Chargers (see [USB Type-C 2.4]) 2.6.1.3 Policy Engine Providers and Consumers are free to implement their own Local Policy on their directly connected Source Ports or Sink Ports. These will be supported by Negotiation and status mechanisms implemented by the Policy Engine for that Port. The Policy Engine interacts directly with the Device Policy Manager to determine the present Local Policy to be enforced. The Device Policy Manager will also inform the Policy Engine whenever there is a change in Local Policy (e.g., Capabilities change). 2.6.2 Message Formation and Transmission 2.6.2.1 Protocol Layer The Protocol Layer forms the Messages used to communicate information between a Port Pair. It is responsible for forming Capabilities Messages, requests and acknowledgments. Additionally, it forms Messages used to swap roles and maintain presence. It receives inputs from the Policy Engine indicating which Messages to send and indicates the responses back to the Policy Engine. The basic protocol uses a push model where the Provider pushes its Capabilities to the Consumer that in turn responds with a request based on the offering. However, the Consumer can asynchronously request the Provider's present Capabilities and can select another voltage/current. Extended Messages of up to a Data Size of MaxExtendedMsgLen can be sent and received provided the Protocol Layer determines that both Port Partners support this capability. When one of both Port Partners do not support Extended Messages of Data Size greater than MaxExtendedMsgLegacyLen then the Protocol Layer supports a Chunking mechanism to break larger Messages into smaller Chunks of size MaxExtendedMsgChunkLen. All Ports that support Extended Messages longer than MaxExtendedMsgLegacyLen are required to support Chunking. 2.6.2.2 PHY Layer The PHY Layer is responsible for sending and receiving Messages across the USB Type-C CC wire and for managing data. PD is a Multi-Drop system, sharing CC between the Port Partners and the Cable Plug(s) that implements Collision Avoidance and recovery mechanisms. The PHY Layer detects errors in the Messages using a CRC. 2.6.3 Collision Avoidance 2.6.3.1 Policy Engine The Policy Engine in a Source will indicate to the Protocol Layer the start and end of each Atomic Message Sequence (AMS) that the Source initiates. The Policy Engine in a Sink will indicate to the Protocol Layer the start of each AMS the Sink initiates. This enables co-ordination of AMS initiation between the Port Partners. 2.6.3.2 Protocol Layer The Protocol Layer in the Source will request the PHY to set the Rp value to SinkTxOK when it is not actively sending Messages. This indicates to the Sink that it can initiate an AMS by sending the first Message in the sequence. The Protocol Layer in the Source will request the PHY Layer to set the Rp value to SinkTxNG to indicate that the Sink cannot initiate an AMS since the Source is about to initiate an AMS. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 71 The Protocol Layer in the Sink, when the Policy Engine indicates that an AMS is being initiated, will wait for the Rp value to be set to SinkTxOK before initiating the AMS by sending the first Message in the sequence. 2.6.3.3 PHY Layer The PHY Layer in the Source will set the Rp value to either SinkTxOK or SinkTxNG as directed by the Protocol Layer. The PHY Layer in the Sink will detect the present Rp value and inform the Protocol Layer. 2.6.4 Power supply 2.6.4.1 Source Each Provider will contain one or more power sources that are shared between one or more Ports. These power sources are controlled by the Local Policy. Source Ports start up in USB Type-C Operation where the Port applies vSafe0V on VBUS and returns to this state on Detach or after a Hard Reset. When the Source detects Attach events it transitions its output to vSafe5V. 2.6.4.2 Sink Consumers are assumed to have one Sink connected to a Port. This Sink is controlled by Local Policy. Sinks start up in USB Default Operation where the Port can operate at vSafe5V with USB default specified current levels and return to this state on Detach or after a Hard Reset. 2.6.4.3 Dual-Role Power Ports Dual-Role Power Ports have the ability to operate as either a Source or a Sink and to swap between the two Power Roles using Power Role Swap or Fast Role Swap. 2.6.4.4 Dead Battery or Lost Power Detection [USB Type-C 2.4] defines mechanisms intended to communicate with and to charge a Sink or DRP with a Dead Battery. 2.6.4.5 VCONN Source The Source Port at Attach, is also the VCONN Source. The responsibility for sourcing VCONN can be swapped between the Source Ports and Sink Ports in a make before break fashion to ensure that the Cable Plugs are continuously powered. To ensure reliable communication with the Cable Plugs only the Port that is the VCONN Source is permitted to communicate with the Cable Plugs. Note: Prior to a Power Role Swap, Data Role Swap or Fast Role Swap each new Source Port needs to ensure that it is the VCONN Source if it needs to communicate with the Cable Plugs after the swap. 2.6.5 DFP/UFP 2.6.5.1 Downstream Facing Port (DFP) The Downstream Facing Port or DFP is equivalent in the USB topology to the Port a USB Device is Attached to. The DFP will also correspond to the USB Host but only if USB Communication is supported while acting as a DFP. Products such as Chargers can be a DFP while not having USB Communication capability. Only the DFP is allowed to control Alternate Mode operation. 2.6.5.2 Upstream Facing Port (UFP) The Upstream Facing Port or UFP is equivalent in the USB topology to the Port on a USB Device that is connected to the USB Host or USB Hub's DFP. The UFP will also correspond to the USB Device but only if USB Communication is supported while acting as a UFP. Products which charge can be a UFP while not having USB Communication capability. Page 72 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.6.5.3 Dual-Role Data Ports Dual-Role Data Ports have the ability to operate as either a DFP or a UFP and to swap between the two Data Roles using Data Role Swap. Note: Products can be Dual-Role Data Ports without being Dual-Role Power Ports that is they can switch logically between DFP and UFP Data Roles even if they are Source-only or Sink-only Ports. 2.6.6 Cable and Connectors The USB Power Delivery specification assumes certified USB cables and associated detection mechanisms as defined in the [USB Type-C 2.4] specification. 2.6.6.1 USB-C Port Control The USB-C® Port Control block provides mechanisms to:  Inform the Device Policy Manager of cable Attach/Detach events.  Inform Sink's Device Policy Manager of the Rp value.  Allow Source's Device Policy Manager to set the Rp value. 2.6.7 Interactions between Non-PD, BC, and PD devices USB Power Delivery only operates when two USB Power Delivery devices are directly connected. When a device finds itself a mixed environment, where the other device does not support the USB Power Delivery Specification, the existing rules on supplying vSafe5V as defined in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications are applied. There are two primary cases to consider:  The USB Host (DFP/Source) is non-PD and as such will not send any Advertisements. An Attached PD Capable device will not see any Advertisements and operates using the rules defined in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications.  The Device (UFP/Sink) is non-PD and as such will not see any Advertisements and therefore will not respond. The USB Host (DFP/Source) will continue to supply vSafe5V to VBUS as specified in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications. 2.6.8 Power Rules Power Rules define voltages and current ranges that are offered by compliant USB Power Delivery Sources and used by a USB Power Delivery Sink for a given value of PDP Rating. See Chapter 10 "Power Rules" for further details.
2.7 - Extended Power Range (EPR) Operation............................................................................ (Page 73)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 73 2.7 Extended Power Range (EPR) Operation Extended Power Range is a Mode that provides for up to 240W which is considerably more power than the 100W the original PD specification (SPR Mode) offered. It is a Mode of operation that can be entered only when an Explicit Contract is in place and both the Ports and the Cable Plug(s) support EPR. Entry into EPR Mode follows a strict process; this assures that the higher voltages, at power levels above 100W, are only transferred between known EPR Capable Sources and EPR Capable Sinks over EPR Capable cables. EPR Sources are capable of both Fixed Supply and Adjustable Voltage Supply (AVS) operation. Maintaining EPR Mode operation also requires maintaining a regular cadence of USB PD communications; loss of communications between the EPR Source and EPR Sink will cause a Hard Reset to be initiated resulting in a return to SPR operation. The EPR Mode entry, operational and exit process is summarized by the following steps: 1) Negotiate and enter into an Explicit Contract in the Standard Power Range. During this step, EPR Capable Sources and Sinks will declare their supported EPR Capabilities through PDO/APDO and RDO exchanges. 2) An EPR Sink, having discovered an EPR Source, can request EPR Mode entry. 3) The EPR Source, having already confirmed that the Attached cable assembly is EPR Capable during the First Explicit Contract Negotiation, will respond to the EPR Sink with an acknowledgment of the EPR Mode entry request. 4) While in EPR Mode: a) The EPR Source sends EPR Capabilities (Fixed Supply PDOs and an AVS APDO) to the EPR Sink which requires the Sink to evaluate and respond as appropriate to adjust the Explicit Contract. b) The EPR Sink maintains a regular cadence of communications with the EPR Source to allow EPR Mode to continue. 5) When either the EPR Source or EPR Sink no longer wants to remain in EPR Mode operation, a normal exit from EPR Mode will first require adjusting the Explicit Contract to a voltage of 20V or lower (SPR (A)PDO) followed by an explicit EPR Mode exit request. a) Source initiated: EPR Source sends an EPR_Source_Capabilities Message that only includes SPR voltages to force the EPR Sink to drop to 20V or below followed by the EPR Mode exit. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. b) Sink initiated; EPR Sink requests a drop to 20V or below followed by the EPR Mode exit. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. Figure 2.6, "Example of a Normal EPR Mode Operational Flow" illustrates an example of a normal EPR Mode operational flow. In this example, at some time during the EPR Mode operation, the Source decides that it needs to exit EPR Mode, so it resends the EPR Capabilities to the Sink with only SPR (A)PDOs to cause the Sink to Negotiate an SPR Contract of 20V or lower and then the Source follows with an EPR Mode exit Message. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. Page 74 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 2.6 Example of a Normal EPR Mode Operational Flow Not illustrated in Figure 2.6, "Example of a Normal EPR Mode Operational Flow", while in EPR Mode operation, the Sink might decide it wants to exit EPR Mode. In this case, the Sink must initiate the exit process by revising its Explicit Contract with the Source at 20V or less followed with an EPR_Mode exit Message. Once EPR Mode is exited, a new SPR Contract is Negotiated to formalize the return to SPR Mode operation. Failure to revise the Explicit Contract to one at 20V or less before attempting to exit EPR Mode will result in a Hard Reset. EPR Source EPR Cable EPR Sink Enter EPR Mode? Cable is EPR? Exit EPR Mode? Establish SPR Contract (Source/Sink EPR Status) Request EPR Mode Accept EPR Mode Establish EPR Contract Maintain PD Repetitive Communications Establish EPR Contract (20V or less) Exit EPR Mode Establish SPR Contract (Source/Sink EPR Status) EPR Mode Entry Phase EPR Mode Operation EPR Mode Exit Phase
2.8 - Charging Models............................................................................................................................. (Page 75)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 75 2.8 Charging Models This section provides a charging model overview for each of the primary power delivery methods: Fixed Supply, Programmable Power Supply and Adjustable Voltage Supply. 2.8.1 Fixed Supply Charging Models USB Power Delivery supports Fixed Supply charging using a set of defined standard voltages with current available up to the limit of the Source's and cable's Advertised Capabilities. As summarized in Table 2.1, "Fixed Supply Power Ranges", the standard voltages are available in either the Standard Power Range (SPR) and/or the Extended Power Range (EPR). 2.8.2 Programmable Power Supply (PPS) Charging Models USB Power Delivery includes support for Programmable Power Supply (PPS) charging using a set of defined standard voltage ranges. With current up to the limit of the Source's and cable's Advertised Capabilities. Additionally, when operating in SPR Mode the current is also limited by the Operating Current field value in the Request Message. Note: PPS operation is not available in EPR Mode. The standard voltage ranges available in the Standard Power Range (SPR) for PPS are summarized in Table 2.2, "PPS Voltage Power Ranges". Table 2.1 Fixed Supply Power Ranges Power Range Available Current and Voltages PDP Range Notes Standard Power Range (SPR) 3A: 5V, 9V, 15V, 20V 5A1: 20V 15 – 60W >60 – 100W Extended Power Range (EPR) 3A2: 5V, 9V, 15V, 20V 5A2: 20V 5A2: 28V, 36V, 48V 15 – 60W >60 – 100W >100 – 240W Requires entry into EPR Mode. 1) Requires 5A cable. 2) Requires EPR cable. Table 2.2 PPS Voltage Power Ranges Available Current Prog Min Voltage (V) Max Voltage (V) PDP Range 3A 9V Prog 5 11 16 – 60W 15V Prog 5 16 20V Prog 5 21 5A1 20V Prog 5 21 61 – 100W 1) Requires 5A cable. Page 76 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.8.3 Adjustable Voltage Supply (AVS) Charging Models USB Power Delivery operating in SPR Mode (when PDP is higher than 27W) and EPR Mode includes support for Adjustable Voltage Supply (AVS) charging using a set of defined standard voltage ranges based on the Source's PDP Rating. The standard voltage ranges available for AVS are summarized in Table 2.3, "AVS Voltage Power Ranges". Table 2.3 AVS Voltage Power Ranges PDP Minimum Voltage (V) Maximum Voltage (V) Maximum Available Current3 Minimum Voltage (V) Maximum Voltage (V) Maximum Available Current >27…45W 9 15 3A N/A >45…60W 9 20 3A >60…100W 9 20 5A1 100…140W 9 20 5A2 15 28 5A2 >140…180W 9 20 5A2 15 36 5A2 >180…240W 9 20 5A2 15 48 5A2 1) Requires 5A cable. 2) Requires an EPR Cable. 3) The maximum available SPR AVS current is determined by the maximum available current in the Fixed Supply 15V PDO in the 9 - 15V range and Fixed Supply 20V PDO in the 15 - 20V range. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 77 3 USB Type-A and USB Type-B Cable Assemblies and Connectors This section has been Deprecated. Please refer to [USBPD 2.0] for details of cables and connectors used in scenar- ios utilizing the BFSK Signaling Scheme in conjunction with USB Type-A or USB Type-B connectors.
4.1 - Interoperability with other USB Specifications................................................................ (Page 78)
Page 78 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4 Electrical Requirements This chapter covers the platform's electrical requirements for implementing USB Power Delivery. 4.1 Interoperability with other USB Specifications USB Power Delivery May be implemented alongside the [USB 2.0], [USB 3.2], [USB4], [USBBC 1.2] and [USB Type- C 2.4] (USB Type-C) specifications. In the case where a Device requests power via [USBBC 1.2] and then the USB Power Delivery Specification, it Shall follow the USB Power Delivery Specification until the Port Pair is Detached or there is a Hard Reset. If the USB Power Delivery connection is lost, the Port Shall return to its default state, see Section 6.8.3, "Hard Reset". 4.2 Dead Battery Detection / Unpowered Port Detection Dead Battery/unpowered operation is when a USB Device needs to provide power to a USB Host under the circumstances where the USB Host:  Has a Dead Battery that requires charging or  Has lost its power source or  Does not have a power source or  Does not want to provide power. Dead Battery charging operation for connections between USB Type-C connectors is defined in [USB Type-C 2.4]. 4.3 Cable IR Ground Drop (IR Drop) Every PD Sink Port capable of USB Communication can be susceptible to unreliable USB Communication if the voltage drop across ground falls outside of the acceptable common mode range for the USB Hi-Speed transceivers data lines due to excessive current draw. Certified USB cabling is specified such that such errors don't typically occur (See [USB Type-C 2.4]). 4.4 Cable Type Detection Standard USB Type-C® cable assemblies are rated for PD voltages higher than vSafe5V and current levels of at least 3A (See [USB Type-C 2.4]). The Source Shall limit maximum Capabilities it offers so as not to exceed the Capabilities of the type of cabling detected. Sources capable of offering more than 3A Shall detect the type of Attached cable and limit the Capabilities they offer based on the current carrying capability of the cable determined by the Cable Capabilities determined using the Discover Identity Command (see Section 6.4.4.3.1, "Discover Identity") sent using SOP’ Communication (see Section 2.4, "SOP* Communication") to the Cable Plug. The Cable VDO returned as part of the Discover Identity Command details the maximum current and voltage values that Shall be Negotiated for a given cable as part of an Explicit Contract. The Cable Discovery process is usually run when the Source is powered up, after a Power Role Swap or Fast Role Swap or when power is applied to a Sink. The method used to detect these events Shall meet the following requirements:  Sources Shall run the Cable Discovery process prior to the Source sending Source_Capabilities Messag- es offering currents in excess of 3A and/or voltages in excess of 20V.  Sinks with USB Type-C connectors Shall select Capabilities from the offered Source Capabilities assum- ing that the Source has already determined the Capabilities of the cable.  Sinks with the Dual-Role Power bit set, Shall respond to a Get_Source_Cap Message by declaring their full Source Capabilities, without limiting them based on the cable's Capabilities.
4.2 - Dead Battery Detection / Unpowered Port Detection................................................... (Page 78)
Page 78 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4 Electrical Requirements This chapter covers the platform's electrical requirements for implementing USB Power Delivery. 4.1 Interoperability with other USB Specifications USB Power Delivery May be implemented alongside the [USB 2.0], [USB 3.2], [USB4], [USBBC 1.2] and [USB Type- C 2.4] (USB Type-C) specifications. In the case where a Device requests power via [USBBC 1.2] and then the USB Power Delivery Specification, it Shall follow the USB Power Delivery Specification until the Port Pair is Detached or there is a Hard Reset. If the USB Power Delivery connection is lost, the Port Shall return to its default state, see Section 6.8.3, "Hard Reset". 4.2 Dead Battery Detection / Unpowered Port Detection Dead Battery/unpowered operation is when a USB Device needs to provide power to a USB Host under the circumstances where the USB Host:  Has a Dead Battery that requires charging or  Has lost its power source or  Does not have a power source or  Does not want to provide power. Dead Battery charging operation for connections between USB Type-C connectors is defined in [USB Type-C 2.4]. 4.3 Cable IR Ground Drop (IR Drop) Every PD Sink Port capable of USB Communication can be susceptible to unreliable USB Communication if the voltage drop across ground falls outside of the acceptable common mode range for the USB Hi-Speed transceivers data lines due to excessive current draw. Certified USB cabling is specified such that such errors don't typically occur (See [USB Type-C 2.4]). 4.4 Cable Type Detection Standard USB Type-C® cable assemblies are rated for PD voltages higher than vSafe5V and current levels of at least 3A (See [USB Type-C 2.4]). The Source Shall limit maximum Capabilities it offers so as not to exceed the Capabilities of the type of cabling detected. Sources capable of offering more than 3A Shall detect the type of Attached cable and limit the Capabilities they offer based on the current carrying capability of the cable determined by the Cable Capabilities determined using the Discover Identity Command (see Section 6.4.4.3.1, "Discover Identity") sent using SOP’ Communication (see Section 2.4, "SOP* Communication") to the Cable Plug. The Cable VDO returned as part of the Discover Identity Command details the maximum current and voltage values that Shall be Negotiated for a given cable as part of an Explicit Contract. The Cable Discovery process is usually run when the Source is powered up, after a Power Role Swap or Fast Role Swap or when power is applied to a Sink. The method used to detect these events Shall meet the following requirements:  Sources Shall run the Cable Discovery process prior to the Source sending Source_Capabilities Messag- es offering currents in excess of 3A and/or voltages in excess of 20V.  Sinks with USB Type-C connectors Shall select Capabilities from the offered Source Capabilities assum- ing that the Source has already determined the Capabilities of the cable.  Sinks with the Dual-Role Power bit set, Shall respond to a Get_Source_Cap Message by declaring their full Source Capabilities, without limiting them based on the cable's Capabilities.
4.3 - Cable IR Ground Drop (IR Drop)............................................................................................. (Page 78)
Page 78 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4 Electrical Requirements This chapter covers the platform's electrical requirements for implementing USB Power Delivery. 4.1 Interoperability with other USB Specifications USB Power Delivery May be implemented alongside the [USB 2.0], [USB 3.2], [USB4], [USBBC 1.2] and [USB Type- C 2.4] (USB Type-C) specifications. In the case where a Device requests power via [USBBC 1.2] and then the USB Power Delivery Specification, it Shall follow the USB Power Delivery Specification until the Port Pair is Detached or there is a Hard Reset. If the USB Power Delivery connection is lost, the Port Shall return to its default state, see Section 6.8.3, "Hard Reset". 4.2 Dead Battery Detection / Unpowered Port Detection Dead Battery/unpowered operation is when a USB Device needs to provide power to a USB Host under the circumstances where the USB Host:  Has a Dead Battery that requires charging or  Has lost its power source or  Does not have a power source or  Does not want to provide power. Dead Battery charging operation for connections between USB Type-C connectors is defined in [USB Type-C 2.4]. 4.3 Cable IR Ground Drop (IR Drop) Every PD Sink Port capable of USB Communication can be susceptible to unreliable USB Communication if the voltage drop across ground falls outside of the acceptable common mode range for the USB Hi-Speed transceivers data lines due to excessive current draw. Certified USB cabling is specified such that such errors don't typically occur (See [USB Type-C 2.4]). 4.4 Cable Type Detection Standard USB Type-C® cable assemblies are rated for PD voltages higher than vSafe5V and current levels of at least 3A (See [USB Type-C 2.4]). The Source Shall limit maximum Capabilities it offers so as not to exceed the Capabilities of the type of cabling detected. Sources capable of offering more than 3A Shall detect the type of Attached cable and limit the Capabilities they offer based on the current carrying capability of the cable determined by the Cable Capabilities determined using the Discover Identity Command (see Section 6.4.4.3.1, "Discover Identity") sent using SOP’ Communication (see Section 2.4, "SOP* Communication") to the Cable Plug. The Cable VDO returned as part of the Discover Identity Command details the maximum current and voltage values that Shall be Negotiated for a given cable as part of an Explicit Contract. The Cable Discovery process is usually run when the Source is powered up, after a Power Role Swap or Fast Role Swap or when power is applied to a Sink. The method used to detect these events Shall meet the following requirements:  Sources Shall run the Cable Discovery process prior to the Source sending Source_Capabilities Messag- es offering currents in excess of 3A and/or voltages in excess of 20V.  Sinks with USB Type-C connectors Shall select Capabilities from the offered Source Capabilities assum- ing that the Source has already determined the Capabilities of the cable.  Sinks with the Dual-Role Power bit set, Shall respond to a Get_Source_Cap Message by declaring their full Source Capabilities, without limiting them based on the cable's Capabilities.
4.4 - Cable Type Detection.................................................................................................................... (Page 78)
Page 78 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4 Electrical Requirements This chapter covers the platform's electrical requirements for implementing USB Power Delivery. 4.1 Interoperability with other USB Specifications USB Power Delivery May be implemented alongside the [USB 2.0], [USB 3.2], [USB4], [USBBC 1.2] and [USB Type- C 2.4] (USB Type-C) specifications. In the case where a Device requests power via [USBBC 1.2] and then the USB Power Delivery Specification, it Shall follow the USB Power Delivery Specification until the Port Pair is Detached or there is a Hard Reset. If the USB Power Delivery connection is lost, the Port Shall return to its default state, see Section 6.8.3, "Hard Reset". 4.2 Dead Battery Detection / Unpowered Port Detection Dead Battery/unpowered operation is when a USB Device needs to provide power to a USB Host under the circumstances where the USB Host:  Has a Dead Battery that requires charging or  Has lost its power source or  Does not have a power source or  Does not want to provide power. Dead Battery charging operation for connections between USB Type-C connectors is defined in [USB Type-C 2.4]. 4.3 Cable IR Ground Drop (IR Drop) Every PD Sink Port capable of USB Communication can be susceptible to unreliable USB Communication if the voltage drop across ground falls outside of the acceptable common mode range for the USB Hi-Speed transceivers data lines due to excessive current draw. Certified USB cabling is specified such that such errors don't typically occur (See [USB Type-C 2.4]). 4.4 Cable Type Detection Standard USB Type-C® cable assemblies are rated for PD voltages higher than vSafe5V and current levels of at least 3A (See [USB Type-C 2.4]). The Source Shall limit maximum Capabilities it offers so as not to exceed the Capabilities of the type of cabling detected. Sources capable of offering more than 3A Shall detect the type of Attached cable and limit the Capabilities they offer based on the current carrying capability of the cable determined by the Cable Capabilities determined using the Discover Identity Command (see Section 6.4.4.3.1, "Discover Identity") sent using SOP’ Communication (see Section 2.4, "SOP* Communication") to the Cable Plug. The Cable VDO returned as part of the Discover Identity Command details the maximum current and voltage values that Shall be Negotiated for a given cable as part of an Explicit Contract. The Cable Discovery process is usually run when the Source is powered up, after a Power Role Swap or Fast Role Swap or when power is applied to a Sink. The method used to detect these events Shall meet the following requirements:  Sources Shall run the Cable Discovery process prior to the Source sending Source_Capabilities Messag- es offering currents in excess of 3A and/or voltages in excess of 20V.  Sinks with USB Type-C connectors Shall select Capabilities from the offered Source Capabilities assum- ing that the Source has already determined the Capabilities of the cable.  Sinks with the Dual-Role Power bit set, Shall respond to a Get_Source_Cap Message by declaring their full Source Capabilities, without limiting them based on the cable's Capabilities.
5.1 - Physical Layer Overview............................................................................................................ (Page 79)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 79 5 Physical Layer 5.1 Physical Layer Overview The Physical Layer (PHY Layer) defines the Signaling technology for USB Power Delivery. This chapter defines the electrical requirements and parameters of the PHY Layer required for interoperability between PDUSB Devices. 5.2 Physical Layer Functions The USB PD PHY Layer consists of a pair of transmitters and receivers that communicate across a single signal wire (CC). All communication is half duplex. The PHY Layer practices Collision Avoidance to minimize communication errors on the channel. The transmitter performs the following functions:  Receive Packet data from the Protocol Layer.  Calculate and append a CRC.  Encode the Packet data including the CRC (i.e., the Payload).  Transmit the Packet (Preamble, SOP*, Payload, CRC and EOP) across the channel using Bi-phase Mark Coding (BMC) over CC. The receiver performs the following functions:  Recover the clock and lock onto the Packet from the Preamble.  Detect the SOP*.  Decode the received data including the CRC.  Detect the EOP and validate the CRC:  If the CRC is Valid, deliver the Packet data to the Protocol Layer.  If the CRC is Invalid, flush the received data.
5.2 - Physical Layer Functions............................................................................................................ (Page 79)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 79 5 Physical Layer 5.1 Physical Layer Overview The Physical Layer (PHY Layer) defines the Signaling technology for USB Power Delivery. This chapter defines the electrical requirements and parameters of the PHY Layer required for interoperability between PDUSB Devices. 5.2 Physical Layer Functions The USB PD PHY Layer consists of a pair of transmitters and receivers that communicate across a single signal wire (CC). All communication is half duplex. The PHY Layer practices Collision Avoidance to minimize communication errors on the channel. The transmitter performs the following functions:  Receive Packet data from the Protocol Layer.  Calculate and append a CRC.  Encode the Packet data including the CRC (i.e., the Payload).  Transmit the Packet (Preamble, SOP*, Payload, CRC and EOP) across the channel using Bi-phase Mark Coding (BMC) over CC. The receiver performs the following functions:  Recover the clock and lock onto the Packet from the Preamble.  Detect the SOP*.  Decode the received data including the CRC.  Detect the EOP and validate the CRC:  If the CRC is Valid, deliver the Packet data to the Protocol Layer.  If the CRC is Invalid, flush the received data.
5.3 - Symbol Encoding............................................................................................................................ (Page 80)
Page 80 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.3 Symbol Encoding Except for the Preamble, all communications on the line Shall be encoded with a line code to ensure a reasonable level of DC-balance and a suitable number of transitions. This encoding makes receiver design less complicated and allows for more variations in the receiver design. 4b5b line code Shall be used. This encodes 4-bit data to 5-bit symbols for transmission and decodes 5-bit symbols to 4-bit data for consumption by the receiver. The 4b5b code provides data encoding along with special symbols. Special symbols are used to signal Hard Reset, and delineate Packet boundaries (see Table 5.1, "4b5b Symbol Encoding"). Table 5.1 4b5b Symbol Encoding Name 4b 5b Symbol Description 0 0000 11110 hex data 0 1 0001 01001 hex data 1 2 0010 10100 hex data 2 3 0011 10101 hex data 3 4 0100 01010 hex data 4 5 0101 01011 hex data 5 6 0110 01110 hex data 6 7 0111 01111 hex data 7 8 1000 10010 hex data 8 9 1001 10011 hex data 9 A 1010 10110 hex data A B 1011 10111 hex data B C 1100 11010 hex data C D 1101 11011 hex data D E 1110 11100 hex data E F 1111 11101 hex data F Sync-1 K-code 11000 Startsynch #1 Sync-2 K-code 10001 Startsynch #2 RST-1 K-code 00111 Hard Reset #1 RST-2 K-code 11001 Hard Reset #2 EOP K-code 01101 EOP End of Packet Error 00000 Shall Not be used Error 00001 Shall Not be used Error 00010 Shall Not be used Error 00011 Shall Not be used Error 00100 Shall Not be used Error 00101 Shall Not be used Sync-3 K-code 00110 Startsynch #3 Error 01000 Shall Not be used Error 01100 Shall Not be used Error 10000 Shall Not be used Error 11111 Shall Not be used
5.4 - Ordered Sets..................................................................................................................................... (Page 81)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 81 5.4 Ordered Sets Ordered sets Shall be interpreted according to Figure 5.1, "Interpretation of ordered sets". An ordered set consists of 4 K-codes sent as shown in Figure 5.1, "Interpretation of ordered sets". Figure 5.1 Interpretation of ordered sets A list of the ordered sets used by USB Power Delivery can be seen in Table 5.2, "Ordered Sets". SOP* is a generic term used in place of SOP/SOP’/SOP’’. The receiver Shall search for all four K-codes. When the receiver finds all four K-codes in the correct place, it Shall interpret this as a Valid ordered set. When the receiver finds three out of four K-codes in the correct place, it May Table 5.2 Ordered Sets Ordered Set Reference Cable Reset Section 5.6.5, "Cable Reset" Hard Reset Section 5.6.4, "Hard Reset" SOP Section 5.6.1.2.1, "Start of Packet Sequence (SOP)" SOP’ Section 5.6.1.2.2, "Start of Packet Sequence Prime (SOP')" SOP’_Debug Section 5.6.1.2.4, "Start of Packet Sequence Prime Debug (SOP'_Debug)" SOP’’ Section 5.6.1.2.3, "Start of Packet Sequence Double Prime (SOP'')" SOP’’_Debug Section 5.6.1.2.5, "Start of Packet Sequence Double Prime Debug (SOP''_Debug)" K-code 4 K-code 3 K-code 2 K-code 1 Transmit last Transmit first Transmit last Transmit first b4 b0 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 Page 82 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 interpret this as a Valid ordered set. The receiver Should ensure that all four K-codes are Valid to avoid ambiguity in detection (see Table 5.3, "Validation of Ordered Sets"). Table 5.3 Validation of Ordered Sets 1st code 2nd code 3rd code 4th code Valid1 Corrupt K-code K-code K-code Valid1 K-code Corrupt K-code K-code Valid1 K-code K-code Corrupt K-code Valid1 K-code K-code K-code Corrupt Valid2 (perfect) K-code K-code K-code K-code Invalid (example) K-code Corrupt K-code Corrupt 1) May be interpreted as a Valid ordered set. 2) Shall be interpreted as a Validordered set.
5.5 - Transmitted Bit Ordering........................................................................................................... (Page 83)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 83 5.5 Transmitted Bit Ordering This section describes the order of bits on the wire that Shall be used when transmitting data of varying sizes. Table 5.4, "Data Size" shows the different data sizes that are possible. Figure 5.2, "Transmit Order for Various Sizes of Data" shows the transmission order that Shall be followed. Figure 5.2 Transmit Order for Various Sizes of Data Table 5.4 Data Size Unencoded Encoded Byte 8-bits 10-bits Word 16-bits 20- bits DWord 32-bits 40-bits b31 b0 b31 Transmit last b16 b15 Transmit first b0 b15 b8 b7 b0 b7 b4 b3 b0 b4 b0 4b5b Transmit last Transmit first BIT 3 BIT 2 BIT 1 BIT 0 BIT 4
5.6 - Packet Format................................................................................................................................. (Page 84)
Page 84 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6 Packet Format The Packet format Shall consist of a Preamble, an SOP*, (see Section 5.6.1.2, "Start of Packet Sequences"), Packet data including the Message Header, a CRC and an EOP (see Section 5.6.1.5, "End of Packet (EOP)"). The Packet format is shown in Figure 5.3, "USB Power Delivery Packet Format" and indicates which parts of the Packet Shall be 4b/5b encoded. Once 4b/5b encoded, the entire Packet Shall be transmitted using BMC over CC. Note: All the bits in the Packet, including the Preamble, are BMC encoded. See Section 6.2.1, "Message Construction" for more details of the Packet construction for Control Messages, Data Messages and Extended Messages. Figure 5.3 USB Power Delivery Packet Format 5.6.1 Packet Framing The transmission starts with a Preamble that is used to allow the receiver to lock onto the carrier. It is followed by a SOP* (Start of Packet). The Packet is terminated with an EOP (End of Packet) K-code. 5.6.1.1 Preamble The Preamble is used to achieve lock in the receiver by presenting an alternating series of "0s" and "1s", so the average frequency is the carrier frequency. Unlike the rest of the Packet, the Preamble Shall Not be 4b/5b encoded. The Preamble Shall consist of a 64-bit sequence of alternating 0s and 1s. The Preamble Shall start with a "0" and Shall end with a "1". 5.6.1.2 Start of Packet Sequences 5.6.1.2.1 Start of Packet Sequence (SOP) SOP is an ordered set. The SOP ordered set is defined as: three Sync-1 K-codes followed by one Sync-2 K-code (see Table 5.5, "SOP Ordered Set"). A Power Delivery Capable Source or Sink Shall be able to detect and communicate with Packets using SOP. If a Valid SOP is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. Sending and receiving of SOP Packets Shall be limited to PD Capable Ports on PDUSB Hosts and PDUSB Devices. Cable Plugs and VPDs Shall neither send nor receive SOP Packets. Table 5.5 SOP Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-1 3 Sync-1 4 Sync-2 Preamble(training for receiver) SOP* (Start Of Packet) Message Header Byte 0 Byte 1 ... ... Byte n-1 Byte n CRC EOP (End Of Packet) LEGEND: Training sequence provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Provided by the Protocol layer, encoded with 4b5b Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 85 Note: PDUSB Devices, even if they have the physical form of a cable (e.g., AMAs), are still required to respond to SOP Packets. 5.6.1.2.2 Start of Packet Sequence Prime (SOP') The SOP’ ordered set is defined as: two Sync-1 K-codes followed by two Sync-3 K-codes (see Table 5.6, "SOP’ Ordered Set"). A VPD Shall have SOP’ Communication capability. A VPD and a Cable Plug capable of SOP’ Communications Shall only detect and communicate with Packets starting with SOP’. A Port needing to communicate with a Cable Plug capable of SOP’ Communications, Attached between a Port Pair will be able to communicate using both Packets starting with SOP’ to communicate with the Cable Plug and starting with SOP to communicate with its Port Partner. For a VPD or a Cable Plug supporting SOP’ Communications, if a Valid SOP’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. For a Port supporting SOP’ Communications if a Valid SOP or SOP’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. When there is no Explicit Contract or an Implicit Contract in place a Sink Shall Not send SOP’ Packets and Shall Discard all Packets starting with SOP’. 5.6.1.2.3 Start of Packet Sequence Double Prime (SOP'') The SOP’’ ordered set is defined as the following sequence of K-codes: Sync-1, Sync-3, Sync-1, Sync-3 (see Table 5.7, "SOP’’ Ordered Set"). A VPD Shall Not have SOP’’ Communication capability. A Cable Plug capable of SOP’’ Communication, Shall have a SOP’ Communication capability in the other Cable Plug. No cable Shall only support SOP’’ Communication. A Cable Plug to which SOP’’ Communication is assigned Shall only detect and communicate with Packets starting with SOP’’ and Shall Discard any other Packets. A Port needing to communicate with such a Cable Plug, Attached between a Port Pair will be able to communicate using Packets starting with SOP’ and SOP’’ to communicate with the Cable Plugs and Packets starting with SOP to communicate with its Port Partner. A Port which supports SOP’’ Communication Shall also support SOP’ Communication and Shall co-ordinate SOP* Communication so as to avoid collisions. For the Cable Plug supporting SOP’’ Communication, if a Valid SOP’’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. For the Port if a Valid SOP* is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. Table 5.6 SOP’ Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-1 3 Sync-3 4 Sync-3 Table 5.7 SOP’’ Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-3 3 Sync-1 4 Sync-3 Page 86 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6.1.2.4 Start of Packet Sequence Prime Debug (SOP'_Debug) The SOP’_Debug ordered set is defined as the following sequence of K-codes: Sync-1, RST-2, RST-2, Sync-3 (see Table 5.8, "SOP’_Debug Ordered Set"). The usage of this Ordered Set is presently undefined. 5.6.1.2.5 Start of Packet Sequence Double Prime Debug (SOP''_Debug) The SOP’’_Debug ordered set is defined as the following sequence of K-codes: Sync-1, RST-2, Sync-3, Sync-2 (see Table 5.9, "SOP’’_Debug Ordered Set"). The usage of this Ordered Set is presently undefined. 5.6.1.3 Packet Payload The Packet data is delivered from the Protocol Layer (see Section 6.2, "Messages") and Shall be encoded with the hex data codes from Table 5.1, "4b5b Symbol Encoding". 5.6.1.4 CRC The CRC Shall be inserted just after the Payload. It is described in Section 5.6.2, "CRC". 5.6.1.5 End of Packet (EOP) The end of Packet marker Shall be a single EOP K-code as defined in Figure 5.1, "Interpretation of ordered sets". This Shall mark the end of the CRC. After the EOP, the CRC-residual Shall be checked. If the CRC is not good, the whole transmission Shall be Discarded, if it is good, the Packet Shall be delivered to the Protocol Layer. Note: An EOP May be used to prematurely terminate a Packet e.g., before sending Hard Reset Signaling. 5.6.2 CRC The Message Header and data Shall be protected by a 32-bit CRC.  CRC-32 protects the data integrity of the data Payload. CRC-32 is defined as follows:  The CRC-32 polynomial Shall be = 04C1_1DB7h.  The CRC-32 Initial value Shall be = FFFF_FFFFh.  CRC-32 Shall be calculated for all bytes of the Payload not inclusive of any Packet framing symbols (i.e., excludes the Preamble, SOP*, EOP).  CRC-32 calculation Shall begin at byte 0, bit 0 and continue to bit 7 of each of the bytes of the Packet.  The remainder of CRC-32 Shall be complemented.  The residual of CRC-32 Shall be C704 DD7Bh. Table 5.8 SOP’_Debug Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 RST-2 3 RST-2 4 Sync-3 Table 5.9 SOP’’_Debug Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 RST-2 3 Sync-3 4 Sync-2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 87 This inversion of the CRC-32 remainder adds an offset of FFFF_FFFFh that will create a constant CRC-32 residual of C704_DD7Bh at the receiver side. Note: The CRC implementation is identical to the one used in [USB 3.2]. Figure 5.4, "CRC-32 Generation" is an illustration of CRC-32 generation. The output bit ordering Shall be as detailed in Table 5.10, "CRC-32 Mapping". Page 88 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.4 CRC-32 Generation The CRC-32 Shall be encoded before transmission. Table 5.10 CRC-32 Mapping CRC-32 Result Bit Position in CRC-32 Field 0 31 1 30 2 29 3 28 4 27 5 26 6 25 7 24 8 23 9 22 10 21 11 20 12 19 13 18 14 17 15 16 16 15 17 14 18 13 19 12 20 11 21 10 22 9 23 8 24 7 25 6 26 5 27 4 28 3 29 2 30 1 31 0 7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24 = Flip Flop 7 6 5 4 3 2 1 0 15141312 1110 9 8 23222120 19181716 31302928 27262524 Data Byte 2 Data Byte 1 Data Byte 0 76543210 Byte Order Bit Order Input 7 B D 1 1 C 4 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 89 5.6.3 Packet Detection Errors CRC errors, or errors detected while decoding encoded symbols using the code table, Shall be treated the same way; the Message Shall be Discarded and a GoodCRC Message Shall Not be returned. While the receiver is processing a Packet, if at any time the CC-line becomes Idle the receiver Shall stop processing the Packet and Discard it (no GoodCRC Message is returned). See Section 5.8.6.1, "Definition of Idle" for the definition of BMC Idle. 5.6.4 Hard Reset Hard Reset Signaling is an ordered set of bytes sent with the purpose to be recognized by the PHY Layer. The Hard Reset Signaling ordered set is defined as: three RST-1 K-codes followed by one RST-2 K-code (see Table 5.11, "Hard Reset Ordered Set"). A device Shall perform a Hard Reset when it receives Hard Reset Signaling. After receiving the Hard Reset Signaling, the device Shall reset as described in Section 6.8.3, "Hard Reset". If a Valid Hard Reset is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. A Cable Plug Shall perform a Hard Reset when it detects Hard Reset Signaling being sent between the Port Partners. After receiving the Hard Reset Signaling, the device Shall reset as described in Section 6.8.3, "Hard Reset". The procedure for sending Hard Reset Signaling Shall be as follows:  If the PHY Layer is currently sending a Message, the Message Shall be interrupted by sending an EOP K- code and the rest of the Message Discarded.  If CC is not Idle, wait for it to become Idle (see Section 5.8.6.1, "Definition of Idle").  Wait tInterFrameGap.  If CC is still Idle send the Preamble followed by the 4 K-codes for Hard Reset Signaling.  Disable the channel (i.e., stop sending and receiving), reset the PHY Layer and inform the Protocol Layer that the PHY Layer has been reset.  Re-enable the channel when requested by the Protocol Layer. Figure 5.5, "Line format of Hard Reset" shows the line format of Hard Reset Signaling which is a Preamble followed by the Hard Reset Ordered Set. Figure 5.5 Line format of Hard Reset Table 5.11 Hard Reset Ordered Set K-Code Number K-Code in Code Table 1 RST-1 2 RST-1 3 RST-1 4 RST-2 Preamble(training for receiver) RST-1 LEGEND: Preamble provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b RST-1 RST-1 RST-2 Page 90 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6.5 Cable Reset Cable Reset Signaling is an ordered set of bytes sent with the purpose to be recognized by the PHY Layer. The Cable Reset Signaling ordered set is defined as the following sequence of K-codes: RST-1, Sync-1, RST-1, Sync-3 (see Table 5.12, "Cable Reset Ordered Set"). Cable Reset Signaling Shall only be sent by the DFP. The Cable Reset Ordered Set is used to reset the Cable Plugs without the need to Hard Reset the Port Partners. The state of the Cable Plug after the Cable Reset Signaling Shall be equivalent to power cycling the Cable Plug. Figure 5.6, "Line format of Cable Reset" shows the line format of Cable Reset Signaling which is a Preamble followed by the Cable Reset Ordered Set. Figure 5.6 Line format of Cable Reset Table 5.12 Cable Reset Ordered Set K-Code Number K-Code in Code Table 1 RST-1 2 Sync-1 3 RST-1 4 Sync-3 Preamble(training for receiver) RST-1 LEGEND: Preamble provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Sync-1 RST-1 Sync-3
5.7 - Collision Avoidance....................................................................................................................... (Page 91)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 91 5.7 Collision Avoidance The PHY Layer Shall monitor the channel for data transmission and only initiate transmissions when CC is Idle. If the bus Idle condition is present, it Shall be considered safe to start a transmission provided the conditions detailed in Section 5.8.5.4, "Inter-Frame Gap" are met. The bus Idle condition Shall be checked immediately prior to transmission. If transmission cannot be initiated, then the Packet Shall be Discarded. If the Packet is Discarded because CC is not Idle, the PHY Layer Shall signal to the Protocol Layer that it has Discarded the Message as soon as CC becomes Idle. See Section 5.8.6.1, "Definition of Idle" for the definition of Idle CC. In addition, during an Explicit Contract, the PHY Layer Shall control the Rp resistor value to avoid collisions between Source and Sink transmissions. The Source Shall set an Rp value corresponding to a current of 3A (SinkTxOK) to indicate to the Sink that it May initiate an AMS. The Source Shall set an Rp value corresponding to a current of 1.5A (SinkTxNG) this Shall indicate to the Sink that it Shall Not initiate an AMS and Shall only respond to Messages as part of an AMS. See [USB Type-C 2.4] (USB Type-C) for details of the corresponding Rp values. During the Implicit Contract that precedes an Explicit Contract (including Power Role Swap and Fast Role Swap) the Rp resistor value is used to specify USB Type-C current and is not used for Collision Avoidance. Table 5.13, "Rp values used for Collision Avoidance" details the Rp values that Shall be used by the Source to control Sink initiation of an AMS. See also Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". Table 5.13 Rp values used for Collision Avoidance Source Rp Parameter Description Sink Operation Source Operation 1.5A@5V SinkTxNG Sink Transmit “No Go,” The Sink Shall Not initiate an AMS once tSinkDelay has elapsed after SinkTxNG is asserted. Source can initiate an AMS tSinkTx after setting Rp to this value. 3A@5V SinkTxOK Sink Transmit “Ok” Sink can initiate an AMS. Source cannot initiate an AMS while it has this value set.
5.8 - Bi-phase Mark Coding (BMC) Signaling Scheme.............................................................. (Page 92)
Page 92 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8 Bi-phase Mark Coding (BMC) Signaling Scheme Bi-phase Mark Coding (BMC) is the PHY Layer Signaling Scheme for carrying USB Power Delivery Messages. This encoding assumes a dedicated DC connection, over the CC wire, which is used for sending PD Messages. Bi-phase Mark Coding is a version of Manchester coding (see [IEC 60958-1]). In BMC, there is a transition at the start of every bit time (UI) and there is a second transition in the middle of the UI when a 1 is transmitted. BMC is effectively DC balanced, (each 1 is DC balanced and two successive zeros are DC balanced, regardless of the number of intervening 1's). It has bounded disparity (limited to 1 bit over an arbitrary Packet, so a very low DC level). Figure 5.7, "BMC Example" illustrates Bi-phase Mark Coding. This example shows the transition from a Preamble to the Sync-1 K-codes of the SOP Ordered Set at the start of a Message. Note: Other K-codes can occur after the Preamble for Signaling such as Hard Reset and Cable Reset. Figure 5.7 BMC Example 5.8.1 Encoding and signaling BMC uses DC coupled baseband Signaling on CC. Figure 5.8, "BMC Transmitter Block Diagram" shows a block diagram for a Transmitter and Figure 5.9, "BMC Receiver Block Diagram" shows a block diagram for the corresponding Receiver. Figure 5.8 BMC Transmitter Block Diagram Preamble Sync-1 Sync-1 0 1 0 1 0 1 0 1 0 1 0 1 0 0 0 0 1 1 Data In BMC to CC Data 4b5b Encoder CRC BMC Encoder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 93 Figure 5.9 BMC Receiver Block Diagram The USB PD baseband signal Shall be driven on the CC wire with a tristate driver that Shall cause a vSwing swing on CC. The tristate driver is slew rate limited (see min rise/fall time in Section 5.8.5, "BMC Transmitter Specifications") to limit coupling to D+/D- and to other signal lines in the USB Type-C fully featured cables (see [USB Type-C 2.4]). This slew rate limiting can be performed either with driver design or an RC filter on the driver output. When sending the Preamble, the transmitter Shall start by transmitting a low level. The receiver Shall tolerate the loss of the first edge. The transmitter May vary the start of the Preamble by tStartDrive min (see Figure 5.10, "BMC Encoded Start of Preamble"). Figure 5.10 BMC Encoded Start of Preamble The transmitter Shall terminate the final bit of the Frame by an edge (the “trailing edge”) to help ensure that the receiver clocks the final bit. If the trailing edge results in the transmitter driving CC low (i.e., the final half-UI of the Frame is high, see Figure 5.11, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition" and Figure 5.12, "Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to- Low Last Transition"), then the transmitter:  Shall continue to drive CC low for tHoldLowBMC.  Should release CC to high impedance as soon as possible after min tHoldLowBMC and Shall release CC by max tEndDriveBMC. Figure 5.11, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition" illustrates the end of a BMC encoded Frame with an encoded zero for which the final bit of the Frame is terminated by a high to low transition. Figure 5.12, "Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to-Low Last Transition" illustrates the end of a BMC Encoded Frame with an encoded one for which the final bit of the Frame is terminated by a high to low transition. Both figures also illustrate the tInterFrameGap timing requirement before the start of the next Frame when the Port has either been transmitting or receiving the previous Frame (see Section 5.8.5.4, "Inter-Frame Gap"). Data from CC 5b4b Decoder CRC BMC Decoder SOP Detect 1UI 1UI 1UI 1UI 1UI 1UI 0 1 0 1 0 1 etc High Impedance (level set by Rp/Rd) tStartDrive Page 94 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.11 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition Figure 5.12 Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to-Low Last Transition If the trailing edge results in the transmitter driving CC high (i.e., the final half-UI of the Frame is low, see Figure 5.13, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition" and Figure 5.14, "Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition"), then the transmitter:  Shall continue to drive CC high for 1 UI.  Then Shall drive CC low for tHoldLowBMC.  Should release CC to high impedance as soon as possible after min tHoldLowBMC and Shall release CC by max tEndDriveBMC. Figure 5.13, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition" illustrates the ending of a BMC encoded Frame that ends with an encoded zero for which the final bit of the Frame is terminated by a low to high transition. Figure 5.14, "Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition" illustrates the ending of a BMC encoded Frame that ends with an encoded one for which the final bit of the Frame is terminated by a low to high transition. Both figures also illustrate the tInterFrameGap timing requirement before the start of the next Frame when the Port has either been transmitting or receiving the previous Frame (see Section 5.8.5.4, "Inter-Frame Gap"). 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 95 Figure 5.13 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition Figure 5.14 Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition Note: There is no requirement to maintain a timing phase relationship between back-to-back Packets. 1UI 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) 1UI 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 1 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) Page 96 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.2 Transmit and Receive Masks 5.8.2.1 Transmit Masks The transmitted signal Shall Not violate the masks defined in Figure 5.15, "BMC Tx 'ONE' Mask", Figure 5.16, "BMC Tx 'ZERO' Mask", Table 5.14, "BMC Tx Mask Definition, X Values" and Table 5.15, "BMC Tx Mask Definition, Y Values" at the output of a load equivalent to the cable model and receiver load model described in Section 5.8.3, "Transmitter Load Model". The masks apply to the full range of Rp/Rd values as defined in [USB Type-C 2.4]. Note: The measurement of the transmitter does not need to accommodate a change in signal offset due to the ground offset when current is flowing in the cable. The transmitted signal Shall have a rise time no faster than tRise. The transmitted signal Shall have a fall time no faster than tFall. The maximum limits on the rise and fall times are enforced by the Tx inner masks. Figure 5.15 BMC Tx 'ONE' Mask Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y6 Y7 Y8 Y9 X9 X10 X11 X12 X13 X14 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 97 Figure 5.16 BMC Tx 'ZERO' Mask Table 5.14 BMC Tx Mask Definition, X Values Name Description Value Units X1Tx Left Edge of Mask 0.015 UI X2Tx see figure 0.07 UI X3Tx see figure 0.15 UI X4Tx see figure 0.25 UI X5Tx see figure 0.35 UI X6Tx see figure 0.43 UI X7Tx see figure 0.485 UI X8Tx see figure 0.515 UI X9Tx see figure 0.57 UI X10Tx see figure 0.65 UI X11Tx see figure 0.75 UI X12Tx see figure 0.85 UI X13Tx see figure 0.93 UI X14Tx Right Edge of Mask 0.985 UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y6 Y7 Y8 Y9 X9 X10 X11 X12 X13 X14 Page 98 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.2.2 Receive Masks A Source using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when sourcing power as defined in Figure 5.17, "BMC Rx 'ONE' Mask when Sourcing Power", Figure 5.18, "BMC Rx 'ZERO' Mask when Sourcing Power" and Table 5.16, "BMC Rx Mask Definition". The Source Rx mask is bounded by sweeping a Tx mask compliant signal, with added vNoiseActive between power neutral and Source offsets. A Consumer using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when sinking power as defined in Figure 5.21, "BMC Rx 'ONE' Mask when Sinking Power", Figure 5.22, "BMC Rx 'ZERO' Mask when Sinking Power" and Table 5.16, "BMC Rx Mask Definition". The Consumer Rx mask is bounded by sweeping a Tx mask compliant signal, with added vNoiseActive between power neutral and Consumer offsets. Every product using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when power neutral as defined in Figure 5.19, "BMC Rx 'ONE' Mask when Power neutral", FFigure 5.20, "BMC Rx 'ZERO' Mask when Power neutral" and Table 5.16, "BMC Rx Mask Definition". Dual-Role Power Devices Shall meet the receiver requirements for a Source when providing power during any transmission using the BMC Signaling Scheme or a Sink when consuming power during any transmission using the BMC Signaling Scheme. Cable Plugs Shall meet the receiver requirements for both a Source and a Sink during any transmission using the BMC Signaling Scheme. The parameters used in the masks are specified to be appropriate to either edge triggered or oversampling receiver implementations. The masks are defined for 'ONE' and 'ZERO' separately as BMC enforces a transition at the midpoint of the unit interval while a 'ONE' is transmitted. The Rx masks are defined to bound the Rx noise after the Rx bandwidth limiting filter with the time constant tRxFilter has been applied. The boundaries of Rx outer mask, Y1Rx and Y5Rx, are specified according to vSwing max and accommodate half of vNoiseActive from cable noise coupling and the signal offset vIRDropGNDC due to the ground offset when current is flowing in the cable. The vertical dimension of the Rx inner mask, Y4Rx - Y2Rx, for power neutral is derived by reducing the vertical dimension of the Tx inner mask, Y7Tx - Y3Tx, at time location X3Tx by vNoiseActive to account for cable noise coupling. The received signal is composed of a waveform compliant to the Tx mask plus vNoiseActive. The vertical dimension of the Rx inner mask for sourcing power is derived by reducing the vertical dimension of the Tx inner mask by vNoiseActive and vIRDropGNDC to account for both cable noise coupling and signal DC offset. Table 5.15 BMC Tx Mask Definition, Y Values Name Description Value Units Y1Tx Lower bound of Out- er mask -0.075 V Y2Tx Lower bound of in- ner mask 0.075 V Y3Tx see figure 0.15 V Y4Tx see figure 0.325 V Y5Tx Inner mask vertical midpoint 0.5625 V Y6Tx see figure 0.8 V Y7Tx see figure 0.975 V Y8Tx see figure 1.04 V Y9Tx Upper Bound of Out- er mask 1.2 V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 99 The received signal is composed of a waveform compliant to the Tx mask plus the maximum value of vNoiseActive plus vIRDropGNDC where the vIRDropGNDC value transitions between the minimum and the maximum values as allowed in this spec. The vertical dimension of the Rx inner mask for sinking power is derived by reducing the vertical dimension of the Tx inner mask by vNoiseActive max and vIRDropGNDC max for account for both cable noise coupling and signal DC offset. The received signal is composed of a waveform compliant to the Tx mask plus the maximum value of vNoiseActive plus vIRDropGNDC where the vIRDropGNDC value transitions between the minimum and the maximum values as allowed in this spec. The center line of the Rx inner mask, Y3Rx, is at half of the nominal vSwing for power neutral, and is shifted up by half of vIRDropGNDC max for sourcing power and is shifted down by half of vIRDropGNDC max for sinking power. The receiver sensitivity Shall be set such that the receiver does not treat noise on an undriven signal path as an incoming signal. Signal amplitudes below vNoiseIdle max Shall be treated as noise when BMC is Idle. Figure 5.17 BMC Rx 'ONE' Mask when Sourcing Power Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Page 100 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.18 BMC Rx 'ZERO' Mask when Sourcing Power Figure 5.19 BMC Rx 'ONE' Mask when Power neutral Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 101 Figure 5.20 BMC Rx 'ZERO' Mask when Power neutral Figure 5.21 BMC Rx 'ONE' Mask when Sinking Power Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Page 102 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.22 BMC Rx 'ZERO' Mask when Sinking Power Table 5.16 BMC Rx Mask Definition Name Description Value Units X1Rx Left Edge of Mask 0.07 UI X2Rx Top Edge of Mask 0.15 UI X3Rx See figure 0.35 UI X4Rx See figure 0.43 UI X5Rx See figure 0.57 UI X6Rx See figure 0.65 UI X7Rx See figure 0.85 UI X8Rx See figure 0.93 UI Y1Rx Lower bound of Outer Mask -0.3325 V Y2Rx Lower Bound of Inner Mask Y3Rx – 0.205 when sourcing power1 or sinking power1. Y3Rx – 0.33 when power neutral1. V Y3Rx Center line of Inner Mask 0.6875 Sourcing Power1. 0.5625 Power Neutral1. 0.4375 Sinking Power1. V Y4Rx Upper bound of Inner mask Y3Rx + 0.205 when sourcing power1 or sinking power1. Y3Rx + 0.33 when power neutral1. V Y5Rx Upper bound of the Outer mask 1.5325 V 1) The position of the center line of the Inner Mask is dependent on whether the receiver is Sourcing or Sinking power or is Power Neutral (see earlier in this section). Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 103 5.8.3 Transmitter Load Model The transmitter load model Shall be equivalent to the circuit outlined in Figure 5.23, "Transmitter Load Model for BMC Tx from a Source" for a Source and Figure 5.24, "Transmitter Load Model for BMC Tx from a Sink" for a Sink. It is formed by the concatenation of a cable load model and a receiver load model. See [USB Type-C 2.4] for details of the Rp and Rd resistors. Note: The parameters zCable_CC, tCableDelay_CC and cCablePlug_CC are defined in [USB Type-C 2.4]. Figure 5.23 Transmitter Load Model for BMC Tx from a Source Figure 5.24 Transmitter Load Model for BMC Tx from a Sink The transmitter system components rOutput and cShunt are illustrated for Informative purposes, and do not form part of the transmitter load model. See Section 5.8.5, "BMC Transmitter Specifications" for a description of the transmitter system design. The value of the modeled cable inductance, La, (in nH) Shall be calculated from the following formula: La= tCableDelay_CCmax* zCable_CCmin tCableDelay_CC is the modeled signal propagation delay through the cable, and zCable_CC is the modeled cable impedance. The modeled cable inductance is 640nH for a cable with zCable_CCmin = 32Ω and tCableDelay_CCmax = 20ns. The value of the modeled cable capacitance, Ca, (in pF) Shall be calculated from the following formula: Ca=tCableDelay_CCmax/zCable_CCmin The modeled cable capacitance is Ca = 625pF for a cable with zCable_CCmin = 32Ω and tCableDelay_CCmax = 20ns. Therefore, Ca/2 = 312.5pF. cCablePlug_CC models the capacitance of the plug at each end of the cable. cReceiver models the capacitance of the receiver. The maximum values Shall be used in each case. cCablePlug_CC cShunt Connector ca 2 La cReceiver Receiver Load Model Transmitter Load Model Output Cable Model cCablePlug_CC ca 2 rOutput Rp Rd cCablePlug_CC cShunt Connector ca 2 La cReceiver Receiver Load Model Transmitter Load Model Output Cable Model cCablePlug_CC ca 2 rOutput Rp Rd Page 104 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: The transmitter load model assumes that there are no other return currents on the ground path. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 105 5.8.4 BMC Common specifications This section defines the common receiver and transmitter requirements. 5.8.4.1 BMC Common Parameters The electrical requirements specified in Table 5.17, "BMC Common Normative Requirements" Shall apply to both the transmitter and receiver. Table 5.17 BMC Common Normative Requirements Name Description Min Nom Max Units Comment fBitRate Bit rate 270 300 330 Kbps tUnitInterval Unit Interval1 3.03 3.70 µs 1/fBitRate 1) Denotes the time to transmit an unencoded data bit, not the shortest high or low times on the wire after encoding with BMC. A single data bit cell has duration of 1UI, but a data bit cell with value 1 will contain a centrally placed 01 or 10 transition in addition to the transition at the start of the cell. Page 106 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.5 BMC Transmitter Specifications The transmitter Shall meet the specifications defined in Table 5.18, "BMC Transmitter Normative Requirements". Table 5.18 BMC Transmitter Normative Requirements Name Description Min Nom Max Units Comment pBitRate Maximum difference between the bit-rate during the part of the Packet following the Preamble and the reference bit-rate. 0.25 % The reference bit rate is the average bit rate of the last 32 bits of the Preamble. rFRSwapTx Fast Role Swap Request transmit driver resistance (excluding cable resistance) 5 Ω Maximum driver resistance of a Fast Role Swap Request transmitter. Assumes a worst case cable resistance of 15Ω as defined in [USB Type-C 2.4]. Note: Based on this value the maximum combined driver and cable resistance of a Fast Role Swap Request transmitter is 20Ω. tEndDriveBMC Time to cease driving the line after the end of the last bit of the Frame. 23 µs Min value is limited by tHoldLowBMC. tFall Fall Time 300 ns 10% and 90% amplitude points, minimum is under an unloaded condition. tHoldLowBMC Time to cease driving the line after the final high-to-low transition. 1 µs Max value is limited by tEndDriveBMC. tInterFrameGap Time from the end of last bit of a Frame until the start of the first bit of the next Preamble. 25 µs tFRSwapTx Fast Role Swap Request transmit duration 60 120 µs Fast Role Swap Request is indicated from the Initial Source to the Initial Sink by driving CC low for this time. tRise Rise time 300 ns 10% and 90% amplitude points, minimum is under an unloaded condition. tStartDrive Time before the start of the first bit of the Preamble when the transmitter Shall start driving the line. -1 1 µs vSwing Voltage Swing 1.05 1.125 1.2 V Applies to both no load condition and under the load condition specified in Section 5.8.3, "Transmitter Load Model". zDriver Transmitter output impedance 33 75 Ω Source output impedance at the Nyquist frequency of [USB 2.0] low speed (750 kHz) while the Source is driving the CC line. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 107 5.8.5.1 Capacitance when not transmitting cReceiver is the capacitance that a DFP or UFP Shall present on the CC line when the DFP or UFP's receiver is not transmitting on the line. The transmitter May have more capacitance than cReceiver while driving the CC line, but Shall meet the waveform mask requirements. Once transmission is complete, the transmitter Shall disengage capacitance in excess of cReceiver from the CC wire within tInterFrameGap. 5.8.5.2 Source Output Impedance Source output impedance zDriver is determined by the driver resistance and the shunt capacitance of the Source and is hence a frequency dependent term. zDriver impacts the noise ingression in the cable. It is specified such that the noise at the Receiver is bounded. zDriver is defined by the following equation: zDriver=rOutput/(1+s*rOutput*cShunt) Figure 5.25 Transmitter diagram illustrating zDriver cShunt Shall Not cause a violation of cReceiver when not transmitting. 5.8.5.3 Bit Rate Drift Limits on the drift in fBitRate are set to help low-complexity receiver implementations. fBitRate is the reciprocal of the average bit duration from the previous 32 bits at a given portion of the Packet. The change in fBitRate during a Packet Shall be less than pBitRate. The reference bit rate (refBitRate) is the average fBitRate over the last 32 bits of the Preamble. fBitRate throughout the Packet, including the EOP, Shall be within pBitRate of refBitRate. pBitRate is expressed as a percentage: pBitRate = | fBitRate - refBitRate | / refBitRate x 100% The transmitter Shall have the same pBitRate for all Packet types. The BIST Carrier Mode and Bit Stream signals are continuous signals without a Payload. When checking pBitRate any set of 1044 bits (20 bit SOP followed by 1024 PRBS bits) within a continuous signal May be considered as the part of the Packet following the Preamble and the 32 preceding bits considered to be the last 32 bits of the Preamble used to compute refBitRate. rOutput cShunt zDriver Page 108 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.5.4 Inter-Frame Gap Figure 5.26, "Inter-Frame Gap Timings" illustrates the inter-Frame gap timings. Figure 5.26 Inter-Frame Gap Timings The transmitter Shall drive the bus for no longer than tEndDriveBMC after transmitting the final bit of the Frame. Before starting to transmit the next Frame's Preamble the transmitter of the next Frame Shall ensure that it waits for tInterFrameGap after either:  Transmitting the previous Frame, for example sending the next Message in an AMS immediately after having sent a GoodCRC Message, or  Receiving the previous Frame, for example when responding to a received Message with a GoodCRC Message, or  Observing an Idle condition on CC (see Section 5.7, "Collision Avoidance"). In this case the Port is waiting to initiate an AMS observes Idle (see Section 5.8.6.1, "Definition of Idle") and then waits tInterFrameGap before transmitting the Frame. See also Section 5.7, "Collision Avoidance" for details on when an AMS can be initiated. Note: The transmitter is also required to verify a bus Idle condition immediately prior to starting transmission of the next Frame (see Section 5.8.6.1, "Definition of Idle"). The transmitter of the next Frame May vary the start of the Preamble by tStartDrive (see Section 5.8.1, "Encoding and signaling"). See also Section 5.8.1, "Encoding and signaling" for figures detailing the timings relating to transmitting, receiving, and observing Idle in relating to Frames. 5.8.5.5 Shorting of Transmitter Output A Transmitter in a Port or Cable Plug Shall tolerate having its output be shorted to ground for tFRSwapTx max. This is due to the potential for Fast Role Swap to be signaled while the Transmitter is in the process of transmitting (see Section 5.8.5.6, "Fast Role Swap Transmission"). End of Frame Preamble Bus driven after end of Frame Bus driven before Preamble tEndDriveBMC tStartDrive tInterFrameGap Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 109 5.8.5.6 Fast Role Swap Transmission The Fast Role Swap process is intended for use by a PDUSB Hub that presently has an external supply and is providing power both through its downstream Ports to USB Devices and upstream to a USB Host such as a laptop. On removal of the external wall supply Fast Role Swap enables a VBUS supply to be maintained by allowing the USB Host to apply vSafe5V when it sees VBUS droop below vSafe5V after having detected Fast Role Swap Signaling. The Fast Role Swap AMS is then used to correctly assign Source/Sink Power Roles and configure the Rp/Rd resistors (see Section 8.3.2.8, "Fast Role Swap"). The Initial Source Shall signal a Fast Role Swap Request by driving CC to ground with a resistance of less than rFRSwapTx for tFRSwapTx. The Initial Source Shall only send a Fast Role Swap Request when it has an Explicit Contract. The Initial Source May send a Fast Role Swap Request even if it has not yet had its Sink Capabilities queried by the Initial Sink. On transmission of the Fast Role Swap Request any pending Messages Shall be Discarded (see Section 6.12.2.2.1, "Common Protocol Layer Message Transmission State Diagram"). The Fast Role Swap Signaling May override any active transmissions. Since the Initial Sink's response to the Fast Role Swap signal is to send an FR_Swap Message, the Initial Source Shall ensure Rp is set to SinkTxOK once the Fast Role Swap Signaling is complete. Page 110 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.6 BMC Receiver Specifications The receiver Shall meet the specifications defined in Table 5.19, "BMC Receiver Normative Requirements". 5.8.6.1 Definition of Idle BMC Collision Avoidance is performed by the detection of signal transitions at the receiver. Detection is active when nTransitionCount transitions occur at the receiver within a time window of tTransitionWindow. After waiting tTransitionWindow without detecting nTransitionCount transitions the bus Shall be declared Idle. Refer to Section 5.8.5.4, "Inter-Frame Gap" for details of when transmissions May start. Table 5.19 BMC Receiver Normative Requirements Name Description Min Nom Max Units Comment cReceiver CC receiver capacitance 200 600 pF The DFP or UFP system Shall have ca- pacitance within this range when not transmitting on the line. nBER Bit error rate, S/N = 25 dB 10-6 nTransitionCount Transitions for signal detect 3 Number of transitions to be detected to declare bus non-Idle. tFRSwapRx Fast Role Swap Request de- tection time 30 50 µs A Fast Role Swap Request results in the receiver detecting a signal low for at least this amount of time. tRxFilter Rx bandwidth limiting filter (digital or analog) 100 ns Time constant of a single pole filter to limit broad-band noise ingression1. tTransitionWindow Time window for detecting non-Idle 12 20 µs vFRSwapCableTx Fast Role Swap Request volt- age detection threshold 490 520 550 mV The Fast Role Swap Request must be be- low this voltage threshold to be detect- ed. vIRDropGNDC Cable Ground IR Drop 250 mV As specified in [USB Type-C 2.4]. vNoiseActive Noise amplitude when BMC is active. 165 mV Peak-to-peak noise from VBUS, [USB 2.0] and SBU lines after the Rx band- width limiting filter with the time con- stant tRxFilter has been applied. vNoiseIdle Noise amplitude when BMC is Idle. 300 mV Peak-to-peak noise from VBUS, [USB 2.0] and SBU lines after the Rx band- width limiting filter with the time con- stant tRxFilter has been applied. zBmcRx Receiver Input Impedance 1 MΩ 1) Broad-band noise ingression is due to coupling in the cable interconnect. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 111 5.8.6.2 Multi-Drop The BMC Signaling Scheme is suitable for use in Multi-Drop configurations containing one or two BMC Multi-Drop transceivers connected to the CC wire, where one or both ends of a cable contains a Multi-Drop transceiver. In this specification the location of the Multi-Drop transceiver is referred to as the Cable Plug. Figure 5.27, "Example Multi-Drop Configuration showing two DRPs" below illustrates a typical Multi-Drop configuration with two DRPs. Figure 5.27 Example Multi-Drop Configuration showing two DRPs The Multi-Drop transceiver Shall obey all the electrical characteristics specified in this section except for those relating to capacitance. The maximum capacitance allowed for the Multi-Drop node when not driving the line is cCablePlug_CC defined in [USB Type-C 2.4]. There are no constraints as to the distance of the Multi-Drop transceiver from the end of the plug. The Multi-Drop transceiver(s) May be located anywhere along the cable including the plugs. The Multi-Drop transceiver suffers less from ground offset compared to the transceivers in the USB Host or USB Device and contributes no significant reflections. It is possible to have a configuration at Attach where one Port can be a VCONN Source and the other Port is not able to be a VCONN Source, such that there is no switch in the second Port. An example of a DFP with a switch Attached to a UFP without a switch is outlined in Figure 5.28, "Example Multi-Drop Configuration showing a DFP and UFP". The capacitance on the CC line for a Port not able to be a VCONN Source Shall still be within cReceiver except when transmitting. Figure 5.28 Example Multi-Drop Configuration showing a DFP and UFP cReceiver Switch VCONN cCablePlug cCablePlug Connector Connector Cable DRP DRP cReceiver Switch VCONN cReceiver Switch VCONN cCablePlug cCablePlug Connector Connector Cable DFP UFP cReceiver Page 112 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.6.3 Fast Role Swap Detection An Initial Sink prepares for a Fast Role Swap by ensuring that once it has detected the Fast Role Swap Request its power supply is ready to respond by applying vSafe5V according to the timing detailed in Section 7.1.13, "Fast Role Swap". The Initial Sink Shall only respond to the Fast Role Swap Request when all the following conditions have been met:  An Explicit Contract has been established and the Sink Capabilities of the Initial Source have been received by, and at the request of, the Initial Sink.  The Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap bits set in its 5V Fixed Supply PDO.  The Initial Sink is able and willing to source the current requested by the Initial Source in the Fast Role Swap bits of its Sink_Capabilities Message. On detection of the Fast Role Swap Request any pending Messages Shall be Discarded (see Section 6.12.2.2.1, "Common Protocol Layer Message Transmission State Diagram"). When the Initial Sink is prepared for a Fast Role Swap and the bus is idle the CC voltage averaged over tFRSwapRx min remains above 0.7V (see [USB Type-C 2.4]) since the Source Rp is either 1.5A or 3.0A. However, vNoiseIdle noise May cause the CC line voltage to reach 0.7V-vNoiseIdle/2 for short durations. When the Initial Sink is prepared for a Fast Role Swap while it is transmitting and the Initial Source is sending a Fast Role Swap Request, the transmission will be attenuated such that the peak CC voltage will not exceed vFRSwapCableTx min. Therefore, when the Initial Sink is prepared for a Fast Role Swap, it Shall Not detect a Fast Role Swap Request when the CC voltage, averaged over tFRSwapRx min, is above 0.7V. When the Initial Sink is prepared for a Fast Role Swap, it Shall detect a CC voltage lower than vFRSwapCableTx min for tFRSwapRx as a Fast Role Swap Request. Note: The Initial Sink is not required to average the CC voltage to meet these requirements. The Initial Sink Shall initiate the Fast Role Swap AMS within tFRSwapInit of detecting the Fast Role Swap Request in order to assign the Rp/Rd resistors to the correct Ports and to re-synchronize the state machines (see Section 6.3.19, "FR_Swap Message"). The Initial Sink Shall become the New Source and Shall start supplying vSafe5V at USB Type-C current (see [USB Type-C 2.4]) no later than tSrcFRSwap after VBUS has dropped below vSafe5V. An Initial Sink Shall disable its VBUS Disconnect Threshold detection circuitry while Fast Role Swap detection is active. Note: While power is transitioning the VCONN Source to the Cable Plug(s) cannot be guaranteed.
5.9 - Built in Self-Test (BIST)............................................................................................................ (Page 113)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 113 5.9 Built in Self-Test (BIST) The following sections define BIST functionality which Shall be supported. 5.9.1 BIST Carrier Mode In BIST Carrier Mode, the PHY Layer Shall send out a BMC encoded continuous string of alternating "1"s and "0"s. This enables the measurement of power supply noise and frequency drift. Note: This transmission is a purely a sequence of alternating bits and Shall Not be formatted as a Packet. See also Section 6.4.3, "BIST Message". 5.9.2 BIST Test Data Mode A BIST Test Data Message is used by the Tester to send various Tester generated Test Patterns to the UUT in order to test the UUT's receiver. See also Section 6.4.3, "BIST Message". Figure 5.29, "Test Frame" shows the Test Frame which Shall be sent by the Tester to the UUT. The BIST Message, with a BIST Test Data BIST Data Object consists of a Preamble, followed by SOP*, followed by the Message Header with a data length of 7 Data Objects, followed a BIST Test Data BIST Data Object, followed by 6 Data Objects containing test data, followed by the CRC and then an EOP. Figure 5.29 Test Frame Preamble(training for receiver) SOP* (Start Of Packet) Test Data 192 bits ... LEGEND: Preamble, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Header Data Objects = 7 BIST Test Data BDO Provided by the Protocol layer, encoded with 4b5b CRC EOP (End Of Packet) ...
6 - Protocol Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 114)
Page 114 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6 Protocol Layer 6.1 Overview This chapter describes the requirements of the USB Power Delivery Specification's Protocol Layer including:  Details of how Messages are constructed and used.  Use of timers and timeout values.  Use of Message and retry counters.  Reset operation.  Error handling.  State behavior. Refer to Section 2.6, "Architectural Overview" for an overview of the theory of operation of USB Power Delivery.
6.1 - Overview......................................................................................................................................... (Page 114)
Page 114 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6 Protocol Layer 6.1 Overview This chapter describes the requirements of the USB Power Delivery Specification's Protocol Layer including:  Details of how Messages are constructed and used.  Use of timers and timeout values.  Use of Message and retry counters.  Reset operation.  Error handling.  State behavior. Refer to Section 2.6, "Architectural Overview" for an overview of the theory of operation of USB Power Delivery.
6.2 - Messages......................................................................................................................................... (Page 115)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 115 6.2 Messages This specification defines three types of Messages:  Control Messages that are short and used to manage the Message flow between Port Partners or to exchange Messages that require no additional data. Control Messages are 16 bits in length.  Data Messages that are used to exchange information between a pair of Port Partners. Data Messages range from 48 to 240 bits in length.  Some examples of Data Messages are:  Those used to expose Capabilities and Negotiate power.  Those used for the BIST.  Those that are Vendor Defined Messages.  Extended Messages that are used to exchange information between a pair of Port Partners. Extended Messages are up to MaxExtendedMsgLen bytes.  Some examples of Extended Messages are:  Those used for Source and Battery information.  Those used for Security.  Those used for Firmware Update.  Those that are Vendor Defined Extended Messages. 6.2.1 Message Construction All Messages Shall be composed of a Message Header and a variable length (including zero) data portion. A Message either originates in the Protocol Layer and is passed to the PHY Layer, or it is received by the PHY Layer and is passed to the Protocol Layer. Figure 6.1, "USB Power Delivery Packet Format for a Control Message" illustrates a Control Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.1 USB Power Delivery Packet Format for a Control Message Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload" illustrates a Data Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Legend: PHY Layer Protocol Layer Page 116 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.2 USB Power Delivery Packet Format including Data Message Payload Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" illustrates an Extended Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.3 USB Power Delivery Packet Format including an Extended Message Header and Payload 6.2.1.1 Message Header Every Message Shall start with a Message Header as shown in:  Figure 6.1, "USB Power Delivery Packet Format for a Control Message"  Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload"  Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and as defined in Table 6.1, "Message Header". The Message Header contains basic information about the Message and the PD Port Capabilities. The Message Header May be used standalone as a Control Message when the Number of Data Objects field is zero or as the first part of a Data Message when the Number of Data Objects field is non-zero. 6.2.1.1.1 Extended The 1-bit Extended field Shall be set to zero to indicate a Control Message or Data Message and set to one to indicate an Extended Message. Table 6.1 Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Extended Section 6.2.1.1.1 14…12 SOP* Number of Data Objects Section 6.2.1.1.2 11…9 SOP* MessageID Section 6.2.1.1.3 8 SOP only Port Power Role Section 6.2.1.1.4 SOP’/SOP’’ Cable Plug Section 6.2.1.1.7 7…6 SOP* Specification Revision Section 6.2.1.1.5 5 SOP only Port Data Role Section 6.2.1.1.6 SOP’/SOP’’ Reserved Section 1.4.2 4…0 SOP* Message Type Section 6.2.1.1.8 Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) 0..7 Data Object(s) Legend: PHY Layer Protocol Layer Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Data (0..260 bytes) Legend: PHY Layer Protocol Layer Extended Message Header (16 bit) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 117 The Extended field Shall apply to all SOP* Packet types. 6.2.1.1.2 Number of Data Objects When the Extended field is set to zero the 3-bit Number of Data Objects field Shall indicate the number of 32-bit Data Objects that follow the Message Header. When this field is zero the Message is a Control Message and when it is non-zero, the Message is a Data Message. The Number of Data Objects field Shall apply to all SOP* Packet types. When both the Extended bit and Chunked bit are set to one, the Number of Data Objects field Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. When the Extended bit is set to one and Chunked bit is set to zero, the Number of Data Objects field Shall be Reserved. Note: In this case, the Message length is determined solely by the Data Size field in the Extended Message Header. 6.2.1.1.3 MessageID The 3-bit MessageID field is the value generated by a rolling counter maintained by the originator of the Message. The MessageIDCounter Shall be initialized to zero at power-on as a result of a Soft Reset, or a Hard Reset. The MessageIDCounter Shall be incremented when a Message is successfully received as indicated by receipt of a GoodCRC Message. Note: The usage of MessageID during testing with BIST Messages is defined in [USBPDCompliance]. The MessageID field Shall apply to all SOP* Packet types. 6.2.1.1.4 Port Power Role The 1-bit Port Power Role field Shall indicate the Port's present Power Role:  0b Sink  1b Source Messages, such as Get_Sink_Cap_Extended, that are only ever sent by a Source, Shall always have the Port Power Role field set to Source. Similarly, Messages such as the Request Message that are only ever sent by a Sink Shall always have the Port Power Role field set to Sink. During the Power Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that the Initial Source's power supply is turned off (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Power Role Swap AMS, for the Initial Sink, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that VBUS is not being driven by the Initial Source and is within vSafe5V (see Figure 8.39, "Successful Fast Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Sink Port, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Figure 8.39, "Successful Fast Role Swap Sequence"). Note: The GoodCRC Message sent by the Initial Sink in response to the PS_RDY Message from the Initial Source will have its Port Power Role field set to Sink since this is initiated by the Protocol Layer. Subsequent Page 118 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Messages initiated by the Policy Engine, such as the PS_RDY Message sent to indicate that VBUS is ready, will have the Port Power Role field set to Source. The Port Power Role field of a received Message Shall Not be verified by the receiver and Shall Not lead to Soft Reset, Hard Reset or Error Recovery if it is incorrect. The Port Power Role field Shall only be defined for SOP Packets. 6.2.1.1.5 Specification Revision The Specification Revision field Shall be one of the following values (except 11b):  00b - Revision 1.0 (Deprecated)  01b - Revision 2.0  10b - Revision 3.x  11b - Reserved, Shall Not be used. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every PD Specification Revision starting from [USB 2.0] for SOP*; the only exception to this is a VPD which Shall Ignore Messages sent with PD Specification Revision 2.0 and earlier. After a physical or logical (USB Type-C® Error Recovery) Attach, a Port discovers the common Specification Revision level between itself and its Port Partner and/or the Cable Plug(s), and uses this Specification Revision level until a Detach, Hard Reset or Error Recovery happens. After detection of the Specification Revision to be used, all PD communications Shall comply completely with the relevant Revision of the PD specification. The 2-bit Specification Revision field of a GoodCRC Message does not carry any meaning and Shall be considered as don't care by the recipient of the Message. The sender of a GoodCRC Message Shall set the Specification Revision field to 01b (Revision 2.0) when responding to a Message that contains 01b in the Specification Revision field of the Message Header. The sender of a GoodCRC Message May set the Specification Revision field to 01b or 10b when responding to a Message that contains 10b (Revision 3.x) in the Specification Revision field of the Message Header. The Specification Revision field Shall apply to all SOP* Packet types. An Attach event or a Hard Reset Shall cause the detection of the applicable Specification Revision to be performed for both Ports and Cable Plugs according to the rules stated below: When the Source Port first communicates with the Sink Port the Specification Revision field Shall be used as described by the following steps: 1) The Source Port sends a Source_Capabilities Message to the Sink Port setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Source Port supports. 2) The Sink Port responds with a Request Message setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Sink Port supports that is equal to or lower than the Specification Revision received from the Source Port. 3) The Source and Sink Ports Shall use the Specification Revision in the Request Message from the Sink in step 2 in all subsequent communications until a Detach, Hard Reset, or Error Recovery happens. Prior to entering the First Explicit Contract, the VCONN Source Shall use the following steps to establish a Specification Revision level: 1) The VCONN Source sends a Discover Identity REQ to the Cable Plug (SOP’) setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports. After a VCONN Swap the required Soft_Reset / Accept Message exchange is used for the same purpose (see Section 6.3.13, "Soft Reset Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 119 2) The Cable Plug responds with a Discover Identity ACK setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports that is equal to or lower than the Specification Revision it received from the Source Port. 3) The Cable Plug and VCONN Source Shall communicate using the lower of the two revisions until an Explicit Contract has been established. 4) Table 6.2, "Revision Interoperability during an Explicit Contract" shows the Specification Revision that Shall be used between the Port Partners and the Cable Plugs when the Specification Revision has been discovered and an Explicit Contract is in place. Notes:  A VCONN Source that does not communicate with the Cable Plug(s) May skip the above procedure.  When a Cable Plug does not respond to a Revision 3.x Discover Identity REQ with a Discover Identity ACK or BUSY the VCONN Source May repeat steps 1-4 using a Revision 2.0 Discover Identity REQ in step 1 before establishing that there is no Cable Plug to communicate with. A VCONN Source that supports Revision 3.x of the Power Delivery Specification May communicate with a Cable Plug also supporting Revision 3.x using Revision 3.x Compliant Communications regardless of the Specification Revision of its Port Partner while no Explicit Contract exists. After an Explicit Contract has been established the Port Partners and Cable Plug(s) Shall use Table 6.2, "Revision Interoperability during an Explicit Contract" to determine the Revision to be used. All data in all Messages Shall be consistent with the Specification Revision field in the Message Header for that particular Message. A Cable Plug Shall Not save the state of the agreed Specification Revision. A Cable Plug Shall respond with the highest Specification Revision it supports that is equal to or lower than the Specification Revision contained in the Message received from the VCONN Source. Cable Plugs Shall operate using the same Specification Revision for both SOP’ and SOP’’. Cable assemblies with two Cable Plugs Shall operate using the same Specification Revision for both Cable Plugs. See Table 6.2, "Revision Interoperability during an Explicit Contract" for details of how various Revisions Shall inter-operate. 6.2.1.1.6 Port Data Role The 1-bit Port Data Role field Shall indicate the Port's present Data Role:  0b UFP  1b DFP Table 6.2 Revision Interoperability during an Explicit Contract Port 1 Revision Cable Plug Revision Port 2 Revision Port to Port Operating Revision Port to Cable Plug Operating Revision 2 2 2 2 2 2 2 3 2 2 2 3 2 2 2 2 3 3 2 2 3 2 2 2 2 3 2 3 3 2 3 3 2 2 2 3 3 3 3 3 Page 120 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Port Data Role field Shall only be defined for SOP Packets. For all other SOP* Packets the Port Data Role field is Reserved and Shall be set to zero. If a USB Type-C Port receives a Message with the Port Data Role field set to the same Data Role as its current Data Role, except for the GoodCRC Message, USB Type-C Error Recovery actions as defined in [USB Type-C 2.4] Shall be performed. For a USB Type-C Port the Port Data Role field Shall be set to the default value at Attachment after a Hard Reset: 0b for a Port with Rd asserted and 1b for a Port with Rp asserted. In the case that a Port is not USB Communications capable, at Attachment a Source Port Shall default to DFP and a Sink Port Shall default to UFP. 6.2.1.1.7 Cable Plug The 1-bit Cable Plug field Shall indicate whether this Message originated from a Cable Plug or VPD:  0b Message originated from a DFP or UFP.  1b Message originated from a Cable Plug or VPD The Cable Plug field Shall only apply to SOP’ Packet and SOP’’ Packet types. 6.2.1.1.8 Message Type The 5-bit Message Type field Shall indicate the type of Message being sent. To fully decode the Message Type, the Number of Data Objects field is first examined to determine whether the Message is a Control Message or a Data Message. Then the specific Message Type can be found in Table 6.5, "Control Message Types" or Table 6.6, "Data Message Types". The Message Type field Shall apply to all SOP* Packet types. 6.2.1.2 Extended Message Header Extended Messages (indicated by the Extended field being set in the Message Header) Shall contain an Extended Message Header following the Message Header as shown in Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and defined in “Table 6.3, "Extended Message Header". Extended Messages contain Data Blocks of Data Size, defined in the Extended Message, that are either sent in a single Message or as a series of Chunks. When the Data Block is sent as a series of Chunks, each Chunk in the series, except for the last Chunk, Shall contain MaxExtendedMsgChunkLen bytes. The last Chunk in the series Shall contain the remainder of the Data Block and so could be less than MaxExtendedMsgChunkLen bytes and Shall be padded to the next 4-byte Data Object boundary. 6.2.1.2.1 Chunked The Port Partners Shall use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine whether to send Messages of Data Size > MaxExtendedMsgLegacyLen bytes in a single Unchunked Extended Message (see Section 6.4.1.2.1.6, "Unchunked Extended Messages Supported" and Section 6.4.2.6, "Unchunked Extended Messages Supported"). Table 6.3 Extended Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Chunked Section 6.2.1.2.1 14…11 SOP* Chunk Number Section 6.2.1.2.2 10 SOP* Request Chunk Section 6.2.1.2.3 9 SOP* Reserved 8…0 SOP* Data Size Section 6.2.1.2.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 121 When either Port Partner only supports Chunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to one.  Every Extended Message of Data Size > MaxExtendedMsgLegacyLen Shall be transmitted between the Port Partners in Chunks  The Number of Data Objects in the Message Header Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When both Port Partners support Unchunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to zero.  Every Extended Message Shall be transmitted between the Port Partners Unchunked.  The Number of Data Objects in the Message Header is Reserved. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When sending Extended Messages to the Cable Plug the VCONN Source Shall only send Chunked Extended Messages. Cable Plugs Shall always send Extended Messages of Data Size > MaxExtendedMsgLegacyLen Chunked and Shall set the Chunked bit in every Extended Message to one. When Extended Messages are supported Chunking Shall be supported. 6.2.1.2.2 Chunk Number The Chunk Number field Shall only be Valid in a Message if the Chunked flag is set to one. If the Chunked flag is set to zero the Chunk Number field Shall also be set to zero. The Chunk Number field is used differently depending on whether the Message is a request for Data, or a requested Data Block being returned:  In a request for data the Chunk Number field indicates the number of the Chunk being requested. The requester Shall only set this field to the number of the next Chunk in the series (the next Chunk after the last received Chunk).  In the requested Data Block the Chunk Number field indicates the number of the Chunk being returned. The Chunk Number for each Chunk in the series Shall start at zero and Shall increment for each Chunk by one up to a maximum of 9 corresponding to 10 Chunks in total. 6.2.1.2.3 Request Chunk The Request Chunk bit Shall only be used for the Chunked transfer of an Extended Message when the Chunked bit is set to 1 (see Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)"). For Unchunked Extended Message transfers, Messages Shall be sent and received without the request/response mechanism (see Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)"). The Request Chunk bit Shall be set to one to indicate that this is a request for a Chunk of a Data Block and Shall be set to zero to indicate that this is a Chunk response containing a Chunk. Except for Chunk zero, a requested Chunk of a Data Block Shall only be returned as a Chunk response to a corresponding request for that Chunk. Both the Chunk request and the Chunk response Shall contain the same value in the Message Type field. When the Request Chunk bit is set to one the Data Size field Shall be zero. Page 122 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.2.1.2.4 Data Size The Data Size field Shall indicate how many bytes of data in total are in Data Block being returned. The total number of data bytes in the Message Shall Not exceed MaxExtendedMsgLen. If the Data Size field is less than MaxExtendedMsgLegacyLen and the Chunked bit is set then the Packet Payload Shall be padded to the next 4-byte Data Object boundary with zeros (0x00). If the Data Size field is greater than expected for a given Extended Message but less than or equal to MaxExtendedMsgLen then the expected fields in the Message Shall be processed appropriately and the additional fields Shall be Ignored. 6.2.1.2.5 Extended Message Examples The following examples illustrate the transmission of Extended Messages both Chunked (Chunked bit is one) and Unchunked (Chunked bit is zero). The examples use a Security_Request Message of Data Size 7 bytes which is responded to by a Security_Response Message of Data Size 30 bytes. The sizes of these Messages are arbitrary and are used to illustrate Message transmission; they are not intended to correspond to genuine security related Messages. During Negotiation of the Explicit Contract after connection, the Port Partners use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine the value of the Chunked bit (see Table 6.4, "Use of Unchunked Message Supported bit"). When both Port Partners support Unchunked Extended Messages then the Chunked bit is zero otherwise the Chunked bit is one. The Chunked bit is used to determine whether:  The Chunk request/response mechanism is used.  Extended Messages are Chunked.  Padding is applied.  The Number of Data Objects field is used. The following examples illustrate the expected usage in each case. 6.2.1.2.5.1 Security_Request/Security_Response Unchunked Example Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Unchunked Extended Messages (Chunked bit is zero) between a USB Host and a Charger. The entire Data Block is returned in one Message. The Chunk request/response mechanism is not used. Table 6.4 Use of Unchunked Message Supported bit Source: Source_Capabilities Message Unchunked Message Supported bit = 0 Unchunked Message Supported bit = 1 Sink: Request Message Unchunked Message Supported bit = 0 Chunked bit = 1 Chunked bit = 1 Unchunked Message Supported bit = 1 Chunked bit = 1 Chunked bit = 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 123 Figure 6.4 Example Security_Request sequence Unchunked (Chunked bit = 0) Figure 6.5, "Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero)" details the Security_Request Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to 0, which in this case is 7 bytes. Figure 6.5 Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero) Figure 6.6, "Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero)" details the Security_Response Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to zero, which in this case is 30 bytes. Host Charger Security_Request (Data Size = 7, Chunked = 0) GoodCRC GoodCRC Security_Response (Data Size = 30, Chunked = 0) Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 0 (Reserved) Data (7 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 Page 124 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.6 Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero) 6.2.1.2.5.2 Security_Request/Security_Response Chunked Example Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Chunked Extended Messages (Chunked bit is one) between a USB Host and a Charger. Note: Chunk Number zero in every Extended Message is sent without the need for a Chunk Request, but Chunk Number one and following need to be requested with a Chunk request. Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 0 (Reserved) Data (30 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B28 B29 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 125 Figure 6.7 Example Security_Request sequence Chunked (Chunked bit = 1) Figure 6.8, "Example Security_Request Message of Data Size 7 (Chunked bit set to 1)" shows the Security_Request Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Three bytes of padding have been added to the Message so that the total number of bytes is a multiple of 32-bits, corresponding to 3 Data Objects. The Number of Data Objects field is set to 3 to indicate the length of this Chunk. The Chunk Number is set to zero and the Data Size field is set to 7 to indicate the length of the whole Extended Message. Host Charger Security_Request (Number of Data Objects = 3, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 7) GoodCRC GoodCRC Security_Response (Number of Data Objects = 7, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 30) Security_Response “Chunk request” (Number of Data Objects = 1, Chunked = 1, Chunk Number = 1, Request Chunk = 1, Data Size = 0) GoodCRC GoodCRC Security_Response (Number of Data Objects = 2, Chunked = 1, Chunk Number = 1, Request Chunk = 0, Data Size = 30) Security_Request Chunk Security_Response Page 126 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.8 Example Security_Request Message of Data Size 7 (Chunked bit set to 1) Figure 6.9, "Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number zero of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. No padding is need for this Chunk since the full 26-byte Payload plus 2-byte Extended Message Header is a multiple of 32-bits, corresponding to 7 Data Objects. The Number of Data Objects field is set to 7 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.9 Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" shows an example of the Message format, byte ordering and padding for the Security_Response Message Chunk request for Chunk Number one shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)". In the Chunk request the Number of Data Objects field in the Message is set to 1 to indicate that the Payload is 32 bits equivalent to 1 data object (see Figure 6.10, "Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1)"). Since the Chunked bit is set to 1 the Chunk request/Chunk response mechanism is used. The Message is a Chunk request so the Request Chunk bit is set to one, and in this case Chunk one is being requested so Chunk Number is set to one. Data Size is set to zero indicating the length of the Data Block being transferred. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits. Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 3 Data (7 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 P0 (0x00) P1 (0x00) P2 (0x00) Padding (3 bytes) Data Object 0 Data Object 1 Data Object 2 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 7 Data (26 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B22 B23 Data Object 0 B24 B25 Data Object 6 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 127 Figure 6.10 Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1) Figure 6.11, "Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number one of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits, corresponding to 2 Data Objects. The Number of Data Objects field is set to 2 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.11 Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 1 Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 1 Data Size = 0 Message Header LSB Message Header MSB Message Header LSB Message Header MSB P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 2 Data (4 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Data Object 1
6.3 - Control Message.......................................................................................................................... (Page 128)
Page 128 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3 Control Message A Message is defined as a Control Message when the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. The Protocol Layer originates the Control Messages (i.e., Accept Message, Reject Message etc.). The Control Message types are specified in the Message Header's Message Type field (bits 4…0) and are summarized in Table 6.5, "Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.5 Control Message Types Bits 4…0 Message Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 0_0001 GoodCRC Source, Sink or Cable Plug See Section 6.3.1. SOP* 0_0010 GotoMin (Deprecated) Deprecated See Section 6.3.2. N/A 0_0011 Accept Source, Sink or Cable Plug See Section 6.3.3. SOP* 0_0100 Reject Source, Sink or Cable Plug See Section 6.3.4. SOP* 0_0101 Ping (Deprecated) Deprecated See Section 6.3.5. SOP only 0_0110 PS_RDY Source or Sink See Section 6.3.6. SOP only 0_0111 Get_Source_Cap Sink or DRP See Section 6.3.7. SOP only 0_1000 Get_Sink_Cap Source or DRP See Section 6.3.8. SOP only 0_1001 DR_Swap Source or Sink See Section 6.3.9. SOP only 0_1010 PR_Swap Source or Sink See Section 6.3.10. SOP only 0_1011 VCONN_Swap Source or Sink See Section 6.3.11. SOP only 0_1100 Wait Source or Sink See Section 6.3.12. SOP only 0_1101 Soft_Reset Source or Sink See Section 6.3.13. SOP* 0_1110 Data_Reset Source or Sink See Section 6.3.14. SOP only 0_1111 Data_Reset_Complete Source or Sink See Section 6.3.15. SOP only 1_0000 Not_Supported Source, Sink or Cable Plug See Section 6.3.16. SOP* 1_0001 Get_Source_Cap_Extended Sink or DRP See Section 6.3.17. SOP only 1_0010 Get_Status Source or Sink See Section 6.3.18. SOP* 1_0011 FR_Swap Sink1 See Section 6.3.19. SOP only 1_0100 Get_PPS_Status Sink See Section 6.3.20. SOP only 1_0101 Get_Country_Codes Source or Sink See Section 6.3.21. SOP only 1_0110 Get_Sink_Cap_Extended Source or DRP See Section 6.3.22. SOP only 1_0111 Get_Source_Info Sink or DRP See Section 6.3.23. SOP Only 1_1000 Get_Revision Source or Sink See Section 6.3.24. SOP* 1_1001… 1_1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 1) In this case the Port is providing vSafe5V however it will have Rd asserted rather than Rp and sets the Port Power Role field to Sink, until the Fast Role Swap AMS has completed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 129 6.3.1 GoodCRC Message The GoodCRC Message Shall be sent by the receiver to acknowledge that the previous Message was correctly received (i.e., had a GoodCRC Message). The GoodCRC Message Shall return the Message's MessageID so the sender can determine that the correct Message is being acknowledged. The first bit of the GoodCRC Message Shall be returned within tTransmit after receipt of the last bit of the previous Message. BIST does not send the GoodCRC Message while in a Continuous BIST Mode (see Section 6.4.3, "BIST Message"). The retry mechanism is triggered when the Message sender fails to receive a GoodCRC Message before the CRCReceiveTimer expires. It is used by the Message sender to detect that the Message was not correctly received by the Message recipient due to noise or other disturbance on the Configuration Channel (CC). The retry mechanism Shall Not be used for any other purpose such as a means of gaining time for processing the required response to the received Message. 6.3.2 GotoMin Message (Deprecated) The GotoMin (Deprecated) Message has been Deprecated. The 0_0010 Message Type is no longer Valid and Shall be responded to by a Not_Supported Message. 6.3.3 Accept Message The Accept Message is a Valid response in the following cases:  It Shall be sent by the Source, in SPR Mode, to signal the Sink that the Source is willing to meet the Request Message.  It Shall be sent by the Source, in EPR Mode, to signal the Sink that the Source is willing to meet the EPR_Request Message.  It Shall be sent by the recipient of the PR_Swap Message to signal that it is willing to do a Power Role Swap and has begun the Power Role Swap AMS.  It Shall be sent by the recipient of the DR_Swap Message to signal that it is willing to do a Data Role Swap and has begun the Data Role Swap AMS.  It Shall be sent by the recipient of the VCONN_Swap Message to signal that it is willing to do a VCONN Swap and has begun the VCONN Swap AMS.  It Shall be sent by the recipient of the FR_Swap Message to indicate that it has begun the Fast Role Swap AMS.  It Shall be sent by the recipient of the Soft_Reset Message to indicate that it has completed its Soft Reset.  It Shall be sent by the recipient of the Enter_USB Message to indicate that it has begun the Enter USB AMS.  It Shall be sent by the recipient of the Data_Reset Message to indicate that it has begun the Data Reset AMS. The Accept Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.6.2, "SenderResponseTimer"). 6.3.4 Reject Message The Reject Message is a Valid response in the following cases:  It Shall be sent to signal the Sink, in SPR Mode, that the Source is unable to meet the Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised. Page 130 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  It Shall be sent to signal the Sink, in EPR Mode, that the Source is unable to meet the EPR_Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is unable to do a Power Role Swap.  It Shall be sent by the recipient of a PR_Swap Message while in EPR Mode.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source, to indicate it is unable to do a VCONN Swap.  It Shall be sent by UFP on receiving an Enter_USB Message to indicate it is unable to enter the requested USB Mode. The sender of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message, on receiving a Reject Message response, Shall Not send this same Message to the recipient until one of the following has occurred:  A New Explicit Contract Negotiation as a result of the Source sending a Source_Capabilities Message or EPR_Source_Capabilities Message. This can be triggered by:  The Source's Device Policy Manager.  A Get_Source_Cap Message sent from the Sink to the Source in SPR Mode.  An EPR_Get_Source_Cap Message sent from the Sink to the Source in EPR Mode.  A Power Role Swap.  A Soft Reset.  A Hard Reset.  A Disconnect/Re-connect.  A Data Role Swap.  A Data Reset. The Sink May send a different Request Message to the one which was rejected but Shall Not repeat the same Request Message, using the same RDO, unless there has been a New Explicit Contract Negotiation, Data Role Swap or Data Reset as described above. The Reject Message Shall be sent within tReceiverResponse of the receipt of the last bit of Message (see Section 6.6.2, "SenderResponseTimer"). Note: The Reject Message is not a Valid response when a Message is not supported. In this case the Not_Supported Message is returned (see Section 6.3.16, "Not_Supported Message"). 6.3.5 Ping Message The Ping (Deprecated) Message has been deprecated. The 0_0101 Message Type is no longer Valid. A Port that receives a Ping (Deprecated) Message May respond with a Not_Supported Message or Ignore the Ping (Deprecated) Message. A Cable Plug that receives a Ping (Deprecated) Message Shall Ignore the Ping (Deprecated) Message. 6.3.6 PS_RDY Message The PS_RDY Message Shall be sent by the Source (or by both the New Sink and New Source during the Power Role Swap AMS or Fast Role Swap AMS) to indicate its power supply has reached the desired operating condition (see Section 8.3.2.2, "Power Negotiation"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 131 6.3.7 Get_Source_Cap Message The Get_Source_Cap (Get Source Capabilities) Message May be sent by a Port to request the Source Capabilities and Dual-Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message"). 6.3.8 Get_Sink_Cap Message The Get_Sink_Cap (Get Sink Capabilities) Message May be sent by a Port to request the Sink Capabilities and Dual- Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message"). 6.3.9 DR_Swap Message The DR_Swap Message is used to exchange DFP and UFP operation between Port Partners while maintaining the direction of power flow over VBUS. The Data Role Swap process can be used by Port Partners whether or not they support USB Communications capability. A DFP that supports USB Communication capability starts as the USB Host on Attachment. A UFP that supports USB Communication capability starts as the USB Device on Attachment. [USB Type-C 2.4] Dual-Role Data (DRD) Ports Shall have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. DFPs and UFPs May have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. A Data Role Swap Shall be regarded in the same way as a cable Detach/ Re-attach in relation to any USB Communication which is ongoing between the Port Partners. If there are any Active Modes between the Port Partners when a DR_Swap Message is a received, then a Hard Reset Shall be performed (see Section 6.4.4.3.4, "Enter Mode Command"). If the Cable Plug has any Active Modes then the DFP Shall Not issue a DR_Swap Message and Shall cause all Active Modes in the Cable Plug to be exited before accepting a Data Role Swap request. The source of VBUS and VCONN Source Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the Data Role Swap process. The DR_Swap Message May be sent by either Port Partner. The recipient of the DR_Swap Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait").  If an Accept Message is sent, the Source and Sink Shall exchange Data Roles.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Data Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Data Role Swap might be possible in the future but that no immediate action Shall be taken. Before a Data Role Swap the initial DFP Shall have its Port Data Role bit set to DFP, and the initial UFP Shall have its Port Data Role bit set to UFP. After a successful Data Role Swap the DFP/Host Shall become the UFP/Device and vice-versa; the new DFP Shall have its Port Data Role bit set to DFP, and the new UFP Shall have its Port Data Role bit set to UFP. Where USB Communication is supported by both Port Partners a USB data connection Should be established according to the new Data Roles. If the Data Role Swap, after having been accepted by the Port Partner, is subsequently not successful, in order to attempt a re-establishment of the connection, USB Type-C Error Recovery actions, such as disconnect, as defined in [USB Type-C 2.4] will be necessary. See Section 8.3.2.9, "Data Role Swap". 6.3.10 PR_Swap Message The PR_Swap Message May be sent by either Port Partner to request an exchange of Power Roles. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). Page 132 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If an Accept Message is sent, the Source and Sink Shall do a Power Role Swap.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Power Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Power Role Swap might be possible in the future but that no immediate action Shall be taken. The PR_Swap Message Shall Not be sent while in EPR Mode. While in EPR Mode if a Power Role Swap is required, an EPR Mode exit Shall be done first. After a successful Power Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the New Source Shall also reset its CapsCounter. The New Source Shall have Rp asserted on the CC wire and the New Sink Shall have Rd asserted on the CC wire as defined in [USB Type-C 2.4]. When performing a Power Role Swap from Source to Sink, the Port Shall change its CC wire resistor from Rp to Rd. When performing a Power Role Swap from Sink to Source, the Port Shall change its CC wire resistor from Rd to Rp. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged by the Power Role Swap process. Note: During the Power Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Power Role Swap, refer to:  Section 7.3.2, "Transitions Caused by Power Role Swap"  Section 8.3.2.5, "Data Reset".  Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram".  Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram".  Section 9.1.2, "Mapping to USB Device States". 6.3.11 VCONN_Swap Message The VCONN_Swap Message Shall be supported by any Port that can operate as a VCONN Source. The VCONN_Swap Message May be sent by either Port Partner to request an exchange of VCONN Source. The recipient of the Message Shall respond by sending an Accept Message, Reject Message, Wait Message (see Section 6.9, "Accept, Reject and Wait") or Not_Supported Message.  If an Accept Message is sent, the Port Partners Shall perform a VCONN Swap. The new VCONN Source Shall send a PS_RDY Message within tVcONNSourceOn to indicate that it is now sourcing VCONN. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of receipt of the last bit of the EOP of the PS_RDY Message.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a VCONN Swap and no action Shall be taken. A Reject Message Shall only be sent by the Port that is not presently the VCONN Source in response to a VCONN_Swap Message. The Port that is presently the VCONN Source Shall Not send a Reject Message in response to VCONN_Swap Message.  If a Wait Message is sent, the requester is informed that a VCONN Swap might be possible in the future but that no immediate action Shall be taken. A Port after losing the VCONN Source role due to incoming VCONN Swap request Shall Not initiate a VCONN Swap until at least tVCONNSwapDelayDFP/ tVCONNSwapDelayUFP after completing the previous VCONN Swap AMS.  If a Not_Supported Message is sent, the requester is informed that VCONN Swap is not supported. The Port that is not presently the VCONN Source May turn on VCONN when a Not_Supported Message is received in response to a VCONN_Swap Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 133 The DFP (Host), UFP (Device) Data Roles and Source of VBUS Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the VCONN Swap process. VCONN Shall be continually sourced during the VCONN Swap process to maintain power to the Cable Plug(s) i.e., make before break. Before communicating with a Cable Plug a Port Shall ensure that it is the VCONN Source and that the Cable Plugs are powered, by performing a VCONN Swap if necessary. Since it cannot be guaranteed that the present VCONN Source is supplying VCONN, the only means to ensure that the Cable Plugs are powered is for a Port wishing to communicate with a Cable Plug to become the VCONN Source. If a Not_Supported Message is returned in response to the VCONN_Swap Message, then the Port is allowed to become the VCONN Source until a Hard Reset or Detach. A VCONN Source that is also a Source can attempt to send a Discover Identity Command using SOP’ to a Cable Plug prior to the establishment of the First Explicit Contract. Note: Even when it is presently the VCONN Source, the Sink is not permitted to initiate an AMS with a Cable Plug unless Rp is set to SinkTxOK (see Section 6.9, "Accept, Reject and Wait"). 6.3.12 Wait Message The Wait Message is a Valid response to one of the following Messages:  It Shall be sent to signal the Sink, in response to a Request Message in SPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent to signal the Sink, in response to a EPR_Request Message in EPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is currently unable to do a Power Role Swap.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is currently unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source to indicate it is currently unable to do a VCONN Swap.  It Shall be sent by the recipient of an Enter_USB Message to indicate it is currently unable to enter the requested USB Mode. The Wait Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.9, "Accept, Reject and Wait"). 6.3.12.1 Wait in response to a Request Message The Wait Message allows the Source time to recover the power it requires to meet the request, e.g., through Re- negotiation with other Sinks or an upstream Source. A Source Should only send a Wait Message in response to a Request Message when an Explicit Contract exists between the Port Partners. The Sink is allowed to repeat the Request Message using the SinkRequestTimer and Shall ensure that there is tSinkRequest after receiving the Wait Message before sending another Request Message. 6.3.12.2 Wait in response to a PR_Swap Message The Wait Message is used when responding to a PR_Swap Message to indicate that a Power Role Swap might be possible in the future. This can occur in any case where the device receiving the PR_Swap Message needs to evaluate the request further e.g., by requesting Sink Capabilities from the originator of the PR_Swap Message. Once it has completed this evaluation one of the Port Partners Should initiate the Power Role Swap process again by sending a PR_Swap Message. The Wait Message is also used where a Hub is operating in hybrid mode when a request cannot be satisfied (see [UCSI]). Page 134 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A Port that receives a Wait Message in response to a PR_Swap Message Shall wait tPRSwapWait after receiving the Wait Message before sending another PR_Swap Message. 6.3.12.3 Wait in response to a DR_Swap Message The Wait Message is used when responding to a DR_Swap Message to indicate that a Data Role Swap might be possible in the future. This can occur in any case where the device receiving the DR_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the Data Role Swap process again by sending a DR_Swap Message. A Port that receives a Wait Message in response to a DR_Swap Message Shall wait tDRSwapWait after receiving the Wait Message before sending another DR_Swap Message. 6.3.12.4 Wait in response to a VCONN_Swap Message The Wait Message is used when responding to a VCONN_Swap Message to indicate that a VCONN_Swap might be possible in the future. This can occur in any case where the device receiving the VCONN_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the VCONN Swap process again by sending a VCONN_Swap Message. A Port that receives a Wait Message in response to a VCONN_Swap Message Shall wait tVCONNSwapWait after receiving the Wait Message before sending another VCONN_Swap Message. A Port that is currently the VCONN Source Shall respond with an Accept Message (rather than a Wait Message) if the Port Partner's Revision and Version, as reported in the Revision Message, is earlier than R3.2 V1.1. A Port Partner supporting an earlier Revision and Version will not expect a Wait Message and will generate a Soft Reset in response. 6.3.12.5 Wait in response to an Enter_USB Message The Wait Message is used, by the UFP, when responding to an Enter_USB Message to indicate that entering the requested USB Mode might be possible in the future. This can occur, for example, in any case where the UFP needs to Negotiate more power to enter the mode. Once the UFP has completed this the DFP Should initiate the Enter USB process again by sending an Enter_USB Message. A DFP that receives a Wait Message in response to an Enter_USB Message Shall wait tEnterUSBWait after receiving the Wait Message before sending another Enter_USB Message. 6.3.13 Soft Reset Message A Soft_Reset Message May be initiated by either the Source or Sink to its Port Partner requesting a Soft Reset. The Soft_Reset Message Shall cause a Soft Reset of the connected Port Pair (see Section 6.8.1, "Soft Reset and Protocol Error"). If the Soft_Reset Message fails a Hard Reset Shall be initiated within tHardReset of the last CRCReceiveTimer expiring after nRetryCount retries have been completed. A Soft_Reset Message is used to recover from Protocol Layer errors; putting the Message counters to a known state to regain Message synchronization. The Soft_Reset Message has no effect on the Source or Sink; that is the previously Negotiated direction. Voltage and current remain unchanged. Modal Operation is unaffected by Soft Reset. However after a Soft Reset has completed, an Explicit Contract Negotiation occurs, in order to re-establish PD Communication and to bring state operation for both Port Partners back to either the PE_SNK_Ready or PE_SRC_Ready states as appropriate (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams"). A Soft_Reset Message May be sent by either the Source or Sink when there is a Message synchronization error. If the error is not corrected by the Soft Reset, Hard Reset Signaling Shall be issued (see Section 6.8.3, "Hard Reset"). A Soft_Reset Message Shall be targeted at a specific entity depending on the type of SOP* Packet used. Soft_Reset Messages sent using SOP Packets Shall Soft Reset the Port Partner only. Soft_Reset Messages sent using SOP’ Packet/ SOP’’ Packets Shall Soft Reset the corresponding Cable Plug only. After a VCONN Swap the VCONN Source needs to reset the Cable Plug's Protocol Layer to ensure MessageID synchronization. If after a VCONN Swap the VCONN Source wants to communicate with a Cable Plug using SOP’ Packets, it Shall issue a Soft_Reset Message using a SOP’ Packet in order to reset the Cable Plug's Protocol Layer. If Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 135 the VCONN Source wants to communicate with a Cable Plug using SOP’’ Packets, it Shall issue a Soft_Reset Message using a SOP’’ Packet in order to reset the Cable Plug's Protocol Layer. 6.3.14 Data_Reset Message The Data_Reset Message May be sent by either the DFP or UFP and Shall reset the USB data connection and exit all Alternate Modes with its Port Partner while preserving the power on VBUS. USB4® Mode capable ports Shall support the Data_Reset Message and other ports May support the Data_Reset Message. The Data_Reset Message Shall Not change the existing:  Power Contract  Data Roles (i.e., which Port is the DFP or UFP) The receiver of the Data_Reset Message Shall respond by sending an Accept Message and then follow the process outlined in the following steps. Neither the sender nor receiver Shall initiate a VCONN Swap until the Data Reset process is complete, and the Data_Reset_Complete Message has been sent. Following receipt of the Accept Message, or GoodCRC following the Accept, depending which Port sends the Data_Reset Message: 1) The DFP Shall:  Disconnect the Port's [USB 2.0] D+/D- signals.  If operating in [USB 3.2] remove the Port's Rx Terminations (see [USB 3.2]).  If operating in [USB4] drive the Port's SBTX to a logic low (see [USB4]). 2) Both the DFP and UFP Shall exit all Alternate Modes if any. 3) Reset the cable:  If the VCONN Source Port is also the UFP, then it Shall run the UFP VCONN Power Cycle process de- scribed in Section 7.1.15.1, "UFP VCONN Power Cycle".  If the VCONN Source Port is also the DFP, then it Shall run the DFP VCONN Power Cycle process de- scribed in Section 7.1.15.2, "DFP VCONN Power Cycle".  The DFP Shall exit the VCONN Power Cycle process as the VCONN Source and be sourcing VCONN. 4) After tDataReset the DFP Shall:  Reconnect the [USB 2.0] D+/D- signals.  If the Port was operating in [USB 3.2] or [USB4] reapply the Port's Rx Terminations (see [USB 3.2]). 5) The Data Reset process is complete; the DFP Shall send a Data_Reset_Complete Message and enter the USB4® Discovery and Entry Flow (See [USB Type-C 2.4]). If the Initiator of the Data_Reset Message does not receive a Valid response within tSenderResponse it Shall enter the ErrorRecovery State. 6.3.15 Data_Reset_Complete Message The Data_Reset_Complete Message Shall be sent by the DFP to the UFP to indicate the completion of the Data Reset process (see Section 6.3.14, "Data_Reset Message"). 6.3.16 Not_Supported Message The Not_Supported Message Shall be sent by a Port or Cable Plug in response to any Message it does not support. Returning a Not_Supported Message is assumed in this specification and has not been called out explicitly except in Section 6.13, "Message Applicability" which defines cases where the Not_Supported Message is returned. Page 136 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3.17 Get_Source_Cap_Extended Message The Get_Source_Cap_Extended Message is sent by a Port to request additional information about a Port's Source Capabilities. The Port Shall respond by returning a Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message"). 6.3.18 Get_Status Message The Get_Status Message is sent by a Port using SOP to request the Port Partner's present status. The Port Partner Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). A Port that receives an Alert Message (see Section 6.4.6, "Alert Message") indicates that the Source or Sink's Status has changed and Should be re-read using a Get_Status Message. The Get_Status Message May also be sent to an Active Cable to get its present status using SOP’/SOP’’. The Active Cable Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). 6.3.19 FR_Swap Message The FR_Swap Message Shall be sent by the New Source within tFRSwapInit after it has detected a Fast Role Swap signal (see Section 5.8.6.3, "Fast Role Swap Detection" and Section 6.6.17.3, "tFRSwapInit"). The Fast Role Swap AMS is necessary to apply Rp to the New Source and Rd to the New Sink and to re-synchronize the state machines. The tFRSwapInit time Shall be measured from the time the Fast Role Swap Request has been sent for tFRSwapRx (max) until the last bit of the EOP of the FR_Swap Message has been transmitted by the PHY Layer. The recipient of the FR_Swap Message Shall respond by sending an Accept Message. After a successful Fast Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the Source Shall also reset its CapsCounter. This ensures that only the Cable Plug responds with a GoodCRC Message to the Discover Identity Command. Prior to the Fast Role Swap AMS, the New Source Shall have Rd asserted on the CC wire and the New Sink Shall have Rp asserted on the CC wire. Note: This is an incorrect assignment of Rp/Rd (since Rp follows the Source and Rd follows the Sink as defined in [USB Type-C 2.4]) that is corrected by the Fast Role Swap AMS. During the Fast Role Swap AMS, the New Source Shall change its CC wire resistor from Rd to Rp and the New Sink Shall change its CC wire resistor from Rp to Rd. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged during the Fast Role Swap process. The Initial Source Should avoid being the VCONN Source (by using the VCONN Swap process) whenever not actively communicating with the cable, since it is difficult for the Initial Source to maintain VCONN power during the Fast Role Swap process. Note: A Fast Role Swap is a "best effort" solution to a situation where a PDUSB Device has lost its external power. This process can occur at any time, even during an AMS in which case error handling such as Hard Reset or [USB Type-C 2.4] Error Recovery will be triggered. Note: During the Fast Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Fast Role Swap process, refer to:  Section 7.1.13, "Fast Role Swap"  Section 7.2.10, "Fast Role Swap"  Section 8.3.3.19.5, "Policy Engine in Source to Sink Fast Role Swap State Diagram"  Section 8.3.3.19.6, "Policy Engine in Sink to Source Fast Role Swap State Diagram" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 137  Section 9.1.2, "Mapping to USB Device States" for VBUS mapping to USB states. 6.3.20 Get_PPS_Status The Get_PPS_Status Message is sent by the Sink to request additional information about a Source's status. The Port Shall respond by returning a PPS_Status Message (see Section 6.5.10, "PPS_Status Message"). 6.3.21 Get_Country_Codes The Get_Country_Codes Message is sent by a Port to request the alpha-2 country codes its Port Partner supports as defined in [ISO 3166]. The Port Partner Shall respond by returning a Country_Codes Message (see Section 6.5.11, "Country_Codes Message"). 6.3.22 Get_Sink_Cap_Extended Message The Get_Sink_Cap_Extended (Get Sink Capabilities Extended) Message is sent by a Port to request additional information about a Port's Sink Capabilities. The Port Shall respond by returning a Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). 6.3.23 Get_Source_Info Message The Get_Source_Info Message is sent by a Port to request the type, maximum Capabilities and present Capabilities of the Port when it is operating as a Source. The Port Shall respond by returning the Source_Info Message (See Section 6.4.11, "Source_Info Message"). 6.3.24 Get_Revision Message The Get_Revision Message is sent by a Port using SOP to request the Revision and Version of the Power Delivery Specification its Port Partner supports. The Port Partner Shall respond by returning a Revision Message (See Section 6.4.12, "Revision Message"). The Get_Revision Message May also be sent to a Cable Plug to request the Revision and Version of the Power Delivery Specification it supports using SOP’/SOP’’. The Active Cable Shall respond by returning a Revision Message (see Section 6.4.12, "Revision Message").
6.4 - Data Message................................................................................................................................ (Page 138)
Page 138 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4 Data Message A Data Message Shall consist of a Message Header and be followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is a non-zero value. There are many types of Data Objects used to compose Data Messages. Some examples are:  Power Data Object (PDO) used to expose a Source Port's power Capabilities or a Sink's power requirements.  Request Data Object (RDO) used by a Sink Port to Negotiate an Explicit Contract.  Vendor Data Object (VDO) used to convey vendor specific information.  BIST Data Object (BDO) used for PHY Layer compliance testing.  Battery Status Data Object (BSDO) used to convey Battery status information.  Alert Data Object (ADO) used to indicate events occurring on the Source or Sink. The type of Data Object being used in a Data Message is defined by the Message Header's Message Type field and is summarized in Table 6.6, "Data Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.6 Data Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0_0001 Source_Capabilities Source or Dual-Role Power See Section 6.4.1.5 SOP only 0_0010 Request Sink only See Section 6.4.2 SOP only 0_0011 BIST Tester, Source or Sink See Section 6.4.3 SOP* 0_0100 Sink_Capabilities Sink or Dual-Role Power See Section 6.4.2 SOP only 0_0101 Battery_Status Source or Sink See Section 6.4.5 SOP only 0_0110 Alert Source or Sink See Section 6.4.6 SOP only 0_0111 Get_Country_Info Source or Sink See Section 6.4.7 SOP only 0_1000 Enter_USB DFP See Section 6.4.8 SOP* 0_1001 EPR_Request Sink See Section 6.4.9 SOP only 0_1010 EPR_Mode Source or Sink See Section 6.4.10 SOP only 0_1011 Source_Info Source See Section 6.4.11 SOP only 0_1100 Revision Source, Sink or Cable Plug See Section 6.4.12 SOP* 0_1101…0 _1110 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0 1111 Vendor_Defined Source, Sink or Cable Plug See Section 6.4.4 SOP* 1_0000…1 _1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 139 6.4.1 Capabilities Message There are two distinct Capabilities Messages: one used while in SPR Mode and another while in EPR Mode. This section defines the Capabilities Messages specific to the SPR Mode and Section 6.5.15, "EPR Capabilities Message" defines the Capabilities Messages specific to the EPR Mode. 6.4.1.1 Power Data Objects Sections Section 6.4.1.5, "SPR Source Capabilities Message" and Section 7.1.3, "Types of Sources" describes the Power Data Objects (PDOs) used in the construction of a Capabilities Message for both SPR Mode and EPR Mode. There are three types of Power Data Objects. They contain additional information beyond that encoded in the Message Header to identify each of the three types of Power Data Objects:  Fixed Supply is used to expose well-regulated fixed voltage power supplies.  Variable Supply is used to expose very poorly regulated power supplies.  Battery Supply is used to expose batteries that can be directly connected to VBUS. There are three types of Augmented Power Data Objects:  SPR PPS is used to expose a power supply whose output voltage can be programmatically adjusted over the Advertised voltage range and limited by the Source to a programmable current limit.  SPR AVS and EPR AVS are used to expose a power supply whose output voltage can be adjusted over the Advertised voltage range but otherwise is equivalent to a Fixed Supply (AVS does not support a programmable current limit). Power Data Objects are also used to expose additional Capabilities that May be utilized, such as in the case of a Power Role Swap. A list of one or more Power Data Objects Shall be sent by the Source to convey its Capabilities. The Sink May then request one of these Capabilities by returning a Request Data Object that contains an index to a Power Data Object, to Negotiate a mutually agreeable Explicit Contract. Where Maximum and Minimum voltage and current values are given in PDOs these Shall be taken to be absolute values. The Source and Sink Shall Not Negotiate a power level that would allow the current to exceed the maximum current supported by their receptacles or the Attached plug (see [USB Type-C 2.4]). The Source Shall limit its offered Capabilities to the maximum current supported by its receptacle and Attached plug. A Sink Shall only make a request from any of the Capabilities offered by the Source. For further details see Section 4.4, "Cable Type Detection". Sources expose their power Capabilities by sending a Source_Capabilities Message. Sinks expose their power requirements by sending a Sink_Capabilities Message. Both are composed of several 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). Table 6.7 Power Data Object Bit(s) Description Value Parameter B31…30 00b Fixed Supply (Vmin = Vmax) 01b Battery 10b Variable Supply (non-Battery) 11b Augmented Power Data Object (APDO) B29…0 Specific Power Capabilities are described by the PDOs in the following sections. Page 140 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Augmented Power Data Object (APDO) is defined to allow support for more than the four PDO types by extending the Power Data Object field from 2 to 4 bits when the B31…B30 are 11b. The generic APDO structure is shown in Table 6.8, "Augmented Power Data Object". Table 6.8 Augmented Power Data Object Bit(s) Description Value Parameter B31…30 11b Augmented Power Data Object (APDO) B29…28 00b SPR PPS 01b EPR AVS 10b SPR AVS 11b Reserved B27…0 Specific Power Capabilities are described by the APDOs in the following sections. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 141 6.4.1.2 Source Power Data Objects This section lists the types of PDOs a Source can use in an SPR Capabilities or EPR Capabilities Message. 6.4.1.2.1 Fixed Supply Power Data Object Table 6.9, "Fixed Supply PDO – Source" describes the Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources"for the electrical requirements of the power supply. Since all USB Providers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29…23. All other Fixed Supply Power Data Objects Shall set bits 29…23 to zero. For a Source offering no Capabilities, the Voltage field (B19…10) Shall be set to 5V and theMaximum Current field Shall be set to 0mA. This is used in cases such as a Dual-Role Power device which offers no Capabilities in its default Power Role or when external power is required to offer power. When a Source wants a Sink, consuming power from VBUS, to go to its lowest power state, the Voltage field (B19…10) Shall be set to 5V and the Maximum Current field Shall be set to 0mA. This is used in cases where the Source wants the Sink to draw pSnkSusp. 6.4.1.2.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.2 USB Suspend Supported Prior to an Explicit Contract or when the USB Communications Capable bit is set to zero, the USB Suspend Supported flag is undefined and Sinks Shall follow the rules for suspend as defined in [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. After an Explicit Contract has been Negotiated:  If the USB Suspend Supported flag is set, then the Sink Shall follow the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and resume. A PDUSB Peripheral May draw up to pSnkSusp during suspend; a PDUSB Hub May draw up to pHubSusp during suspend (see Section 7.2.3, "Sink Standby"). Table 6.9 Fixed Supply PDO – Source Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ for Dual-Role Power device. B28 USB Suspend Supported Set to ‘1’ if USB suspend is supported. B27 Unconstrained Power Set to ‘1’ if unconstrained power is available. B26 USB Communications Capable Set to ‘1’ if capable of USB Communications capable B25 Dual-Role Data Set to ‘1’ for a Dual-Role Data device. B24 Unchunked Extended Messages Supported Set to ‘1 if Unchunked Extended Messages are supported. B23 EPR Capable Set to ‘1 if EPR Capable. B22 Reserved Reserved – Shall be set to zero. B21…20 Peak Current Peak Current value. B19…10 Voltage Voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 142 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the USB Suspend Supported flag is cleared, then the Sink Shall Not apply the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and May continue to draw the Negotiated power. Note: When USB is suspended, the USB device state is also suspended. Sinks May indicate to the Source that they would prefer to have the USB Suspend Supported flag cleared by setting the No USB Suspend flag in a Request Message (see Section 6.4.2.5, "No USB Suspend"). 6.4.1.2.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.2.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sources capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.2.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Data bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.1.2.1.7 EPR Mode Capable The EPR Capable bit is a Static bit that Shall be set if the Source is designed to supply more than 100W and operate in EPR Mode. When this bit is set, an EPR Source:  Operating in SPR Mode Shall only send an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Message  May only enter EPR Mode when the Cable and the Sink also report that they are EPR Capable. 6.4.1.2.1.8 Peak Current The USB Power Delivery Fixed Supply is only required to deliver the amount of current requested in the Operating Current field (IoC) of an RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current (see Section 7.2.8, "Sink Peak Current Operation") period needed to maintain such average power. The Peak Current field allows a Source to Advertise this additional capability. This capability is intended for direct Port to Port connections only and Shall Not be offered to downstream Sinks via a Hub. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 143 Every Fixed Supply PDO Shall contain a Peak Current field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current field in the corresponding Fixed Supply PDO (see Table 6.10, "Fixed Power Source Peak Current Capability"). Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding Fixed Supply PDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall also set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send the Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. 6.4.1.2.2 Variable Supply (non-Battery) Power Data Object Table 6.11, "Variable Supply (non-Battery) PDO – Source" describes a Variable Supply (non-Battery) (10b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall define the range that output voltage Shall fall within. This does not indicate the voltage that will be supplied, except it Shall fall within that range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. The Minimum Voltage field value Shall Not be less than 80% of the Maximum Voltage field value. 6.4.1.2.3 Battery Supply Power Data Object Table 6.12, "Battery Supply PDO – Source" describes a Battery Supply (01b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall represent the Battery's voltage range. The Battery Shall be capable of supplying the Power value over the entire voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: The Battery Supply PDO uses power instead of current. Table 6.10 Fixed Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Table 6.11 Variable Supply (non-Battery) PDO – Source Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 144 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Sink May monitor the Battery voltage. Table 6.12 Battery Supply PDO – Source Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Allowable Power Maximum allowable power in 250mW units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 145 6.4.1.2.4 Augmented Power Data Object (APDO) The voltage fields define the output voltage range over which the power supply Shall be adjustable in 20mV steps in SPR PPS Mode and 100mV steps in both SPR AVS Mode and EPR AVS Mode. The Maximum Current field contains the current the Programmable Power Supply Shall be capable of delivering over the Advertised voltage range. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. 6.4.1.2.4.1 SPR Programmable Power Supply APDO Table 6.13, "SPR Programmable Power Supply APDO – Source" below describes the SPR PPS (1100b) APDO for a Source operating in SPR Mode and supplying 5V up to 21V. The PPS APDO is used primarily for Sink Directed Charge Directed Charge of a Battery in the Sink. When applying a current to the Battery greater than the cable supports, a high efficiency fixed voltage scaler May be used in the Sink to reduce the cable current. 6.4.1.2.4.1.1 PPS Power Limited When the PPS Power Limited bit is set, the SPR PPS Source Shall operate in the same way as if the PPS Power Limited bit is clear (see Section 7.1.4.2, "SPR Programmable Power Supply (PPS)" with the below exception:  May supply power that exceeds the Source's rated PDP within the Optional operating area in Figure 7.7, "SPR PPS Constant Power". When the PPS Power Limited bit is cleared, the SPR PPS Source Shall deliver the Maximum Current field value up to the Maximum Voltage as Advertised in its APDO. The SPR PPS Source Shall Not reject an RDO with an Operating Current field value that is less than or equal to the Maximum Current field value in the APDO even if the requested Operating Current field value is greater than the Source's PDP/requested Output voltage. Table 6.13 SPR Programmable Power Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27 PPS Power Limited Set to ‘1’ when PPS Power Limited B26…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Page 146 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.2.4.2 SPR Adjustable Voltage Supply APDO Table 6.14, "SPR Adjustable Voltage Supply APDO – Source" below describes the SPR AVS (1110b) APDO for a Source operating in SPR Mode and supplying 9V up to 20V. 6.4.1.2.4.2.1 Peak Current The Peak Current field follows the same definition as for the Peak Current field (see Section 6.4.1.2.1.8, "Peak Current" and Table 6.10, "Fixed Power Source Peak Current Capability". 6.4.1.2.4.3 EPR Adjustable Voltage Supply APDO Table 6.15, "EPR Adjustable Voltage Supply APDO – Source" below describes the EPR AVS (1101b) APDO for a Source operating in EPR Mode and supplying 15V up to 48V. 6.4.1.2.4.3.1 PDP The PDP field Shall contain the AVS Port's PDP. See Section 10.2.3.3, "Optional Normative Extended Power Range (EPR)" and Figure 10.6, "Valid EPR AVS Operating Region" for more information regarding how PDP in the AVS APDO relates to maximum available current. 6.4.1.2.4.3.2 Peak Current The USB Power Delivery EPR AVS is only required to deliver the amount of current requested in the Operating Current field (IoC) of an AVS RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current period needed to maintain such average power (see Section 7.2.8, "Sink Peak Current Operation"). The Peak Current (Source EPR AVS) field allows a Source to Advertise this additional capability. This Table 6.14 SPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…26 Peak Current Peak Current (see Table 6.10, "Fixed Power Source Peak Current Capability")) B25…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the maximum voltage in the SPR AVS range is 15V. Table 6.15 EPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Peak Current (Source EPR AVS) Peak Current (see Table 6.16, "EPR AVS Power Source Peak Current Capability") B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 147 capability is intended for direct Port to Charger connections only and Shall Not be offered to downstream Sinks via a Hub. Every EPR AVS APDO Shall contain a Peak Current (Source EPR AVS) field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current (Source EPR AVS) field in the corresponding EPR AVS APDO (see Table 6.16, "EPR AVS Power Source Peak Current Capability". Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding EPR AVS APDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send a Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. Table 6.16 EPR AVS Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Page 148 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.3 Sink Power Data Objects This section lists the types of PDOs a Sink can use in an SPR or EPR Capabilities Message. 6.4.1.3.1 Sink Fixed Supply Power Data Object Table 6.17, "Fixed Supply PDO – Sink" describes the Sink Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Sink Shall set the Voltage field to its required voltage and the Operational Current field to its required operating current. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. Since all USB Consumers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29 through 20. All other Fixed Supply Power Data Objects Shall set bits 29…20 to zero. For a Sink requiring no power from the Source, the Voltage field Shall be set to 5V and the Operational Current field Shall be set to 0mA. 6.4.1.3.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.2 Higher Capability In the case that the Sink needs more than vSafe5V (e.g., 15V) to provide full functionality, then the Higher Capability bit Shall be set. 6.4.1.3.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. Table 6.17 Fixed Supply PDO – Sink Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ if Dual-Role Power supported B28 Higher Capability Set to ‘1’ if Higher Capability supported B27 Unconstrained Power Set to ‘1’ if Unconstrained Power supported B26 USB Communications Capable Set to ‘1’ if USB Communications Capable B25 Dual-Role Data Dual-Role Data B24...23 Fast Role Swap required USB Type-C Current Fast Role Swap required USB Type-C current (see also [USB Type-C 2.4]): Value Description 00b Fast Role Swap not supported (default) 01b Default USB Port 10b 1.5A@5V 11b 3.0A@5V B22...20 Reserved Reserved – Shall be set to zero. B19…10 Voltage Voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 149 To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.3.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sinks capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.3.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Dataa bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.6 Fast Role Swap USB Type-C Current The Fast Role Swap required USB Type-C Current field Shall indicate the current level the Sink will require after a Fast Role Swap has been performed. The Initial Source Shall Not transmit a Fast Role Swap Request if the Fast Role Swap required USB Type-C Current field is set to zero. Initially when the New Source applies vSafe5V it will have Rd asserted but Shall provide the USB Type-C current indicated by the New Sink in this field. If the New Source is not able to supply this level of current, it Shall Not perform a Fast Role Swap. When Rp is asserted by the New Source during the Fast Role Swap AMS (see Section 6.3.19, "FR_Swap Message"), the value of USB Type-C current indicated by Rp Shall be the same or greater than that indicated in the Fast Role Swap required USB Type-C Current field. 6.4.1.3.2 Variable Supply (non-Battery) Power Data Object Table 6.18, "Variable Supply (non-Battery) PDO – Sink" describes a Variable Supply (non-Battery) (10b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Current field Shall be set to the operational current that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.3 Battery Supply Power Data Object Table 6.19, "Battery Supply PDO – Sink" describes a Battery Supply (01b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. Table 6.18 Variable Supply (non-Battery) PDO – Sink Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Page 150 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Power field Shall be set to the operational power that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: Only the Battery Supply PDO uses power instead of current. Required operating power is defined as the amount of power a given device needs to be functional. This value could be the maximum power the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.4 Augmented Power Data Objects See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Maximum and Minimum voltage fields Shall be set to the output voltage range that the Sink requires to operate. 6.4.1.3.4.1 SPR Programmable Power Supply APDO Table 6.20, "SPR Programmable Power Supply APDO – Sink" below describes a SPR PPS APDO for a Sink operating in SPR Mode and consuming 21V or less. The Maximum Current field Shall be set to the maximum current the Sink requires over the voltage range. The maximum current is defined as the maximum amount of current the device needs to fully support its function (e.g., Sink Directed Charge). Table 6.19 Battery Supply PDO – Sink Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Power Operational Power in 250mW units Table 6.20 SPR Programmable Power Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 151 6.4.1.3.4.2 SPR Adjustable Voltage Supply APDO Table 6.21, "SPR Adjustable Voltage Supply APDO – Sink" below describes the SPR AVS (1110b) APDO for a Sink operating in SPR AVS Mode. The Maximum Current 15V/Maximum Current 20V fields in the SPR AVS APDO for the Sink is defined as the maximum current the device needs to fully support its function. 6.4.1.3.4.3 EPR Adjustable Voltage Supply APDO Table 6.22, "EPR Adjustable Voltage Supply APDO – Sink" below describes a EPR AVS APDO for a Sink operating in EPR AVS Mode. The PDP field in the EPR AVS APDO for the Sink is defined as the PDP the device needs to fully support its function. 6.4.1.4 SPR Capabilities Message Construction An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) Shall have at least one Power Data Object for vSafe5V. The SPR Capabilities Message Shall also contain the sending Port's information followed by up to 6 additional Power Data Objects. Power Data Objects in an SPR Capabilities Message Shall be sent in the following order: 1) The vSafe5V Fixed Supply PDO Shall always be the first (A)PDO. 2) The remaining Fixed Supply PDOs, if present, Shall be sent in voltage order; lowest to highest. 3) The Battery Supply PDOs if present Shall be sent in Minimum voltage order; lowest to highest. 4) The Variable Supply (non-Battery) PDOs, if present, Shall be sent in Minimum voltage order; lowest to highest. 5) The SPR AVS APDO, if present, Shall be sent. 6) The Programmable Power Supply APDOs, if present, Shall be sent in Maximum voltage order, lowest to highest. Note: The EPR Capabilities Message construction is defined in Section 6.5.15.1, "EPR Capabilities Message Construction". Table 6.21 SPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum Current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the Maximum voltage in the SPR AVS range is 15V. Table 6.22 EPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Reserved Reserved – Shall be set to zero. B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Page 152 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.12, "SPR Capabilities Message Construction" describes the construction of an SPR Capabilities Message. The Message will always have at least one Fixed Supply 5V PDO and may have up to six more PDOs depending on the Source Capabilities. Figure 6.12 SPR Capabilities Message Construction Figure 6.13 Example Capabilities Message with 2 Power Data Objects In the 27W Source as shown in Figure 6.13, "Example Capabilities Message with 2 Power Data Objects", the Number of Data Objects field is 2: vSafe5V plus one other voltage. Power Data Objects (PDO) and Augmented Power Data Objects (APDO) are identified by the Message Header's Message Type field. They are used to form SPR Capabilities Messages. 6.4.1.5 SPR Source Capabilities Message Sources send a Source_Capabilities Message either as part of advertising Port Capabilities, or in response to a Get_Source_Cap Message. See Section 6.5.15.2, "EPR_Source_Capabilities Message" for information about EPR Source Capabilities Messages. Following a Hard Reset, a power-on event or plug insertion event, a Source Port Shall send a Source_Capabilities Message after every SourceCapabilityTimer timeout as an Advertisements that Shall be interpreted by the Sink Port on Attachment. The Source Shall continue sending a minimum of nCapsCount Source_Capabilities Messages until a GoodCRC Message is received. Additionally, a Source_Capabilities Message Shall only be sent by a Port in the following cases:  By the Source Port from the PE_SRC_Ready state upon a change in its ability to supply power to this Port.  By a Source Port or Dual-Role Power Port in response to a Get_Source_Cap Message.  Optionally by a Source Port from the PE_SRC_Ready state when available power in a multi-Port system changes, even if the Source Capabilities for this Port have not changed. A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual- Role Power ports presently operating as a Sink. Each Power Data Object Shall describe a specific Source capability such as a Battery (e.g., 2.8-4.1V) or a Fixed Supply (e.g., 15V) at a maximum allowable current. The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sources Shall minimally offer one Power Data Object that reports vSafe5V. A Source Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Source capability and voltage. Header 2 bytes PDO 1 PDO 2 PDO 3 PDO 4 PDO 5 PDO 6 PDO 7 001b 010b 011b 100b 101b 110b 111b Header No. of Data Objects = 2 Fixed 5V PDO Fixed 9V PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 153 Sinks with Accessory Support do not source VBUS (see [USB Type-C 2.4]). Sinks with Accessory Support are still considered Sources when sourcing VCONN to an Accessory even though VBUS is not applied; in this case they Shall Advertise vSafe5V with the Maximum Current field set to 0mA in the first Power Data Object. The main purpose of this is to enable the Sink with Accessory Support to get into the PE_SRC_Ready State to enter an Alternate Mode. A Sink in SPR Mode Shall evaluate every Source_Capabilities Message it receives and Shall respond with a Request Message. If its power consumption exceeds the Source Capabilities it Shall Re-negotiate so as not to exceed the Source's most recently Advertised Capabilities. A Sink, in SPR Mode, in an Explicit Contract with a PPS APDO, Shall periodically re-request the PPS APDO at least every tPPSRequest until either:  The Sink requests something other than PPS APDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. A Sink in EPR Mode that receives a Source_Capabilities Message in response to a Get_Source_Cap Message Shall Not respond with a Request Message. If a Sink in EPR Mode receives a Source_Capabilities Message, not in response to a Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. A Source that has accepted a Request Message with a Programmable RDO Shall issue Hard Reset Signaling if it has not received a Request Message with a Programmable RDO within tPPSTimeout. The Source Shall discontinue this behavior after:  Receiving a Request Message with a Fixed Supply, Variable Supply or Battery Supply RDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. 6.4.1.6 SPR Sink Capabilities Message Sinks send a Sink_Capabilities Message (see Section 6.4.2, "Request Message") in response to a Get_Sink_Cap Message. See Section 6.5.15.3, "EPR_Sink_Capabilities Message" for more information about the Capabilities Message. A USB Power Delivery capable Sink, upon detecting vSafe5V on VBUS and after a SinkWaitCapTimer timeout without seeing a Source_Capabilities Message, Shall send a Hard Reset. If the Attached Source is USB Power Delivery capable, it responds by sending Source_Capabilities Messages thus allowing power Negotiations to begin. A Sink Port Shall report power levels it is able to operate at in a series of 32-bit Power Data Objects (see Section Table 6.7, "Power Data Object"). These are returned as part of a Sink_Capabilities Message in response to a Get_Sink_Cap Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). This is similar to that used for Source Port Capabilities with equivalent Power Data Objects for Fixed Supply, Variable Supply and Battery Supply as defined in this section. Power Data Objects are used to convey the Sink Port's operational power requirements including Dual-Role Power Ports presently operating as a Source. Each Power Data Object Shall describe a specific Sink operational power level, such as a Battery Supply (e.g., 2.8- 4.1V) or a Fixed Supply (e.g., 15V). The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sinks Shall minimally offer one Power Data Object with a power level at which the Sink can operate. A Sink Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Sink capability and voltage. All Sinks Shall include one Power Data Object that reports vSafe5V even if they require additional power to operate fully. In the case where additional power is required for full operation the Higher Capability bit Shall be set. Page 154 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.6.1 Use by Dual-Role Power devices Dual-Role Power devices send a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message") as part of advertising Port Capabilities when operating in Source role. Dual-Role Power devices send a Source_Capabilities Message in response to a Get_Source_Cap Message regardless of their present operating role. Similarly Dual-Role Power devices send a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message") in response to a Get_Sink_Cap Message regardless of their present operating role. 6.4.1.6.2 Management of the Power Reserve This section has been removed. Refer to Section 8.2.5, "Managing Power Requirements". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 155 6.4.2 Request Message A Request Message Shall be sent by a Sink to request power during the request phase of an SPR power Negotiation. The Request Data Object Shall be returned by the Sink making a request for power. It Shall be sent in response to the most recent Source_Capabilities Message (see Section 8.3.2.2, "Power Negotiation") when in SPR Mode. A Request Message Shall return one and only one Sink Request Data Object that Shall identify the Power Data Object being requested. The Source Shall respond to a Request Message with an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Request Message includes the requested power level. For example, if the Source_Capabilities Message includes a Fixed Supply PDO that offers 9V @ 1.5A and if the Sink only wants 9V @ 0.5A, it will set the Operating Current field to 50 (i.e., 10mA * 50 = 0.5A). The request uses a different format depending on the kind of power requested.  The Fixed Supply Power Data Object and Variable Supply Power Data Object share a common format shown in Table 6.23, "Fixed and Variable Request Data Object".  The Battery Supply Power Data Object uses the format shown in Table 6.24, "Battery Request Data Object".  The PPS Request Data Object's format is shown in Table 6.25, "PPS Request Data Object".  The AVS Request Data Object's format is shown in Table 6.26, "AVS Request Data Object". The Request Data Objects are also used by the EPR_Request Message when operating in EPR Mode. See Section 6.4.9, "EPR_Request Message" for information about the use of the EPR_Request Message. A Source operating in EPR Mode that receives a Request Message Shall initiate a Hard Reset. Table 6.23 Fixed and Variable Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0 - Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Current Operating current in 10mA units B9…0 Maximum Operating Current Maximum Operating current 10mA units Page 156 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.24 Battery Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0- Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Power Operating Power in 250mW units B9…0 Maximum Operating Power Maximum Operating Power in 250mW units Table 6.25 PPS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 20mV units. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Table 6.26 AVS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 25mV units, the least two significant bits Shall be set to zero making the effective voltage step size 100mV. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 157 6.4.2.1 Object Position The value in the Object Position field Shall indicate which object in the Source_Capabilities Message or EPR_Source_Capabilities Message the RDO refers to. The value 0001b always indicates the 5V Fixed Supply PDO as it is the first object following the Source_Capabilities Message’s Message Header or EPR_Source_Capabilities Message’s Extended Message Header. The number 0010b refers to the next PDO and so forth. The Object Position field values 0001b…0111b Shall only be used to refer to SPR (A)PDOs. SPR (A)PDOs May be requested by either a Request or an EPR_Request Message. Object positions 1000b…1011b Shall only be used to refer to EPR (A)PDOs. EPR (A)PDOs Shall only be requested by an EPR_Request Message. If the Object Position field in a Request Message contains a value greater than 0111b, the Source Shall send Hard Reset Signaling. 6.4.2.2 GiveBack Flag (Deprecated) The Giveback flag has been Deprecated and Shall be set to zero. 6.4.2.3 Capability Mismatch A Capabilities Mismatch occurs when the Source cannot satisfy the Sink's power requirements based on the Source Capabilities it has offered. In this case the Sink Shall make a Valid request from the offered Source Capabilities and Shall set the Capability Mismatch bit (see Section 8.2.5.2, "Power Capability Mismatch"). When a Capabilities Mismatch condition does not exist, the Sink Shall Not set the Capability Mismatch bit. When a Sink returns a Request Data Object with the Capability Mismatch bit set in response to a Source Capabilities Message, it indicates that it wants more power than the Source is currently offering. This can be due to either a specific voltage that is not being offered or there is not sufficient current for the voltages that are being offered. Sources whose Port Reported PDP is less than their Port Present PDP (see Section 6.4.11, "Source_Info Message") Shall respond to the Requests with the Capability Mismatch bit set as follows. The Source within tCapabilitiesMismatchResponse of the PS_RDY Message Shall send a new Source Capabilities Message that offers either: 1) The set of Source Capabilities to minimally satisfy the Sink's requirements based on what it actually requires for full operation by evaluating the: a) Sink_Capabilities_Extended Message(if supported by the Sink) and/or b) Sink_Capabilities or EPR_Sink_Capabilities Message. 2) The set of Source Capabilities the Source can supply at this time based on the Port Present PDP. To prevent looping, Sources Should Not send a new Source Capabilities Message in response to subsequent Request Message with the Capability Mismatch flag set until its Port Present PDP changes. Once a Guaranteed Capability Source that has responded to a Capability Mismatch, it Shall Not subsequently send out another Source Capabilities Message at a lower PDP unless the power required by the Sink (as indicated in its Sink Capabilities Message or Sink_Capabilities_Extended Message) has also been reduced. Sources wishing to manage their power May periodically check the Sink Capabilities Message or Sink_Capabilities_Extended Message to determine whether these have changed. Note: A Source Capabilities Message refers to a Source_Capabilities Message or an EPR_Source_Capabilities Message, and a Sink Capabilities Message refers to a Sink_Capabilities Message or EPR_Sink_Capabilities Message, Request refers to a Request Message or EPR_Request depending on operating mode. In this context a Valid Request Message means the following:  The Object Position field Shall contain a reference to an object that was present in the last received Source Capabilities Message.  The Operating Current/Operating Power field Shall contain a value which is less than or equal to the maximum current/power offered by the selected (A)PDO the Source Capabilities Message. Page 158 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.2.4 USB Communications Capable The USB Communications Capable flag Shall be set to one when the Sink has USB data lines and is capable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. The USB Communications Capable flag Shall be set to zero when the Sink does not have USB data lines or is otherwise incapable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. This is used by the Source to determine operation in certain cases such as USB suspend. If the USB Communications Capable flag has been set to zero by a Sink, then the Source needs to be aware that USB Suspend rules cannot be observed by the Sink. 6.4.2.5 No USB Suspend The No USB Suspend flag May be set by the Sink to indicate to the Source that this device is requesting to continue its Explicit Contract during USB Suspend. Sinks setting this flag typically have functionality that can use power for purposes other than USB Communication e.g., for charging a Battery. The Source uses this flag to evaluate whether it Should re-issue the Source_Capabilities Message with the USB Suspend Supported flag cleared. 6.4.2.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.2.7 EPR Mode Capable The EPR Capable bit Shall indicate whether or not the Sink is capable of operating in EPR Mode. When the Sink's ability to operate in EPR Mode changes, it Shall send a new Request Message with the updated EPR Capable bit set in the RDO. 6.4.2.8 Operating Current The Operating Current field in the Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. A new Request Message or EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The Operating Current field in the SPR Programmable Request Data Object is used in addition by the Sink to request the Source for the Current Limit level it needs. When the request is accepted the Source's output current supplied into any load Shall be less than or equal to the Operating Current value. When the Sink attempts to consume more current, the Source Shall reduce the output voltage so as not to exceed the Operating Current value. The Operating Current field in the AVS Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. Note: A Source in AVS Mode, unlike the SPR Source in PPS Mode, does not support current limit; the Sink is responsible not to take more current than it requested. A new Request / EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The value in the Operating Current field Shall Not exceed the value in the Maximum Current field of the Source_Capabilities Message. For EPR AVS, the Operating Current field Shall Not exceed the PDP / Output voltage rounded down to the nearest 50 mA. This field Shall apply to the Fixed Supply, Variable Supply, Programmable and AVS RDOs. 6.4.2.9 Maximum Operating Current The Maximum Operating Current field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Current field in the Request Message or EPR_Request Message, the field Shall be set equal to the value of the Operating Current field. To ensure backward compatibility, the Source Should Ignore this field. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 159 This field Shall apply to the Fixed Supply and Variable Supply RDO in SPR Mode and the Fixed Supply RDO in EPR Capable. 6.4.2.10 Operating Power The Operating Power field in the Request Data Object Shall be set to the highest power the Sink will draw throughout the Explicit Contract. This field Shall apply to the Battery Supply RDO. 6.4.2.11 Maximum Operating Power The Maximum Operating Power field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Power field in the Request Message, the field Shall be set equal to the value of the Operating Power field. To ensure backward compatibility, the Source Should Ignore this field. This field Shall apply to the Battery Supply RDO. 6.4.2.12 Output Voltage The Output Voltage field in the Programmable and AVS Request Data Objects Shall be set by the Sink to the voltage the Sink requires as measured at the Source's output connector. The Output Voltage field Shall be greater than or equal to the Minimum Voltage field and less than or equal to the Maximum Voltage field in the Programmable Power Supply and AVS APDOs, respectively. This field Shall apply to the Programmable RDO and AVS RDO. 6.4.3 BIST Message The BIST Message is sent to request the Port to enter a PHY Layer test mode (see Section 5.9, "Built in Self-Test (BIST)") that performs one of the following functions:  Enter a Continuous BIST Mode to send a continuous stream of test data to the Tester.  Enter and leave a Shared Capacity Group test mode. The Message format is as shown in Figure 6.14, "BIST Message". Figure 6.14 BIST Message All Ports Shall be able to be a Unit Under Test (UUT) only when operating at vSafe5V. All of the following BIST Modes Shall be supported:  Process reception of a BIST Carrier Mode BIST Data Object that Shall result in the generation of the appropriate carrier signal.  Process reception of a BIST Test Data BIST Data Object that Shall result in the Message being Ignored. UUTs with Ports constituting a Shared Capacity Group (see [USB Type-C 2.4]) Shall support the following BIST Mode:  Process reception of a BIST Shared Test Mode Entry BIST Data Object that Shall cause the UUT to enter BIST Shared Capacity Test Mode; a mode in which the UUT offers its full Source Capabilities on every Port in the Shared Capacity Group. Header No. of Data Objects = 1 or 7 BIST Data Object Page 160 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Process reception of a BIST Shared Test Mode Exit BIST Data Object that Shall cause the UUT to exit the BIST Shared Capacity Test Mode. When a Port receives a BIST Message BIST Data Object for a BIST Mode when not operating at vSafe5V, the BIST Message Shall be Ignored. When a Port receives a BIST Message BIST Data Object for a BIST Mode it does not support the BIST Message Shall be Ignored. When a Port or Cable Plug receives a BIST Message BIST Data Object for a Continuous BIST Mode the Port or Cable Plug enters the requested BIST Mode and Shall remain in that BIST Mode for tBISTContMode and then Shall return to normal operation (see Section 6.6.7.2, "BISTContModeTimer"). The usage model of the PHY Layer BIST Modes generally assumes that some controlling agent will request a test of its Port Partner. In Section 8.3.2.15, "Built in Self-Test (BIST)" there is a sequence description of the test sequences used for compliance testing. The fields in the BIST Data Object are defined in the Table 6.27, "BIST Data Object". 6.4.3.1 BIST Carrier Mode Upon receipt of a BIST Message, with a BIST Carrier Mode BIST Data Object, the UUT Shall send out a continuous string of BMC encoded alternating "1"s and "0"s. The UUT Shall exit the Continuous BIST Mode within tBISTContMode of this Continuous BIST Mode being enabled (see Section 6.6.7.2, "BISTContModeTimer"). 6.4.3.2 BIST Test Data Mode Upon receipt of a BIST Message, with a BIST Test Data BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter BIST Test Data Mode in which it sends no further Messages except for GoodCRC Messages in response to received Messages. See Section 5.9.2, "BIST Test Data Mode" for the definition of the Test Frame. The test Shall be ended by sending Hard Reset Signaling to reset the UUT. Table 6.27 BIST Data Object Bit(s) Value Parameter Description Reference Applicability B31…28 0000b…0100b Reserved Shall Not be used Section 1.4.2 - 0101b BIST Carrier Mode Request Transmitter to enter BIST Carrier Mode Section 6.4.3.1 Mandatory 0110b…0111b Reserved Shall Not be used Section 1.4.2 - 1000b BIST Test Data Sends a Test Frame. Section 6.4.3.2 Mandatory 1001b BIST Shared Test Mode Entry Requests UUT to enter BIST Shared Capacity Test Mode. Section 6.4.3.3.1 Mandatory for UUTs with shared capacity 1010b BIST Shared Test Mode Exit Requests UUT to exit BIST Shared Capacity Test Mode. Section 6.4.3.3.2 Mandatory for UUTs with shared capacity 1011b…1111b Reserved Shall Not be used Section 1.4.2 - B27…0 Reserved Shall be set to zero. Section 1.4.2 - Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 161 6.4.3.3 BIST Shared Capacity Test Mode A Shared Capacity Group of Ports share a common power source that is not capable of simultaneously powering all the ports to their full Source Capabilities (see [USB Type-C 2.4]). The BIST Shared Capacity Test Mode Shall only be implemented by ports in a Shared Capacity Group. The UUT Shared Capacity Group of Ports Shall contain one or more Ports, designated as Master Ports, that recognize both the BIST Shared Test Mode Entry BIST Data Object and the BIST Shared Test Mode Exit BIST Data Object. 6.4.3.3.1 BIST Shared Test Mode Entry When any master Port in a Shared Capacity Group receives a BIST Message with a BIST Shared Test Mode Entry BIST Data Object, while in the PE_SRC_Ready State, the UUT Shall enter a compliance test mode where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. Ports in the Shared Capacity Group that are not Master Ports Shall Not enter compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Upon receipt of a BIST Message, with a BIST Shared Test Mode Entry BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter the BIST Shared Capacity Test Mode. On entering this mode, the UUT Shall send a new Source_Capabilities Message from each Port in the Shared Capacity Group within tBISTSharedTestMode. The Tester will not exceed the shared capacity during this mode. 6.4.3.3.2 BIST Shared Test Mode Exit Upon receipt of a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, the UUT Shall return a GoodCRC Message and Shall exit the BIST Shared Capacity Test Mode. If any other Message, aside from a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, is received while in BIST Shared Capacity Test Mode this Shall Not cause the UUT to exit the BIST Shared Capacity Test Mode On exiting the mode, the UUT May send a new Source_Capabilities Message to each Port in the Shared Capacity Group or the UUT May perform ErrorRecovery on each Port. Ports in the Shared Capacity Group that are not Master Ports Shall Not exit compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Ports in the Shared Capacity Group that are not Master Ports Should Not exit compliance mode on receiving the BIST Shared Test Mode Exit BIST Data Object.  The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off.  The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs:  Hard Reset  Cable Reset  Soft Reset  Data Role Swap  Power Role Swap  Fast Role Swap  VCONN Swap.  The UUT May leave BIST Shared Capacity Test Mode if the Tester makes a request that exceeds the Capabilities of the UUT. Page 162 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4 Vendor Defined Message The Vendor_Defined Message (VDM) is provided to allow vendors to exchange information outside of that defined by this specification. A Vendor_Defined Message Shall consist of at least one Vendor Data Object (VDO), the VDM Header, and May contain up to a maximum of six additional VDOs. To ensure vendor uniqueness of Vendor_Defined Messages, all Vendor_Defined Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. Two types of Vendor_Defined Messages are defined: Structured VDMs and Unstructured VDMs. A Structured VDM defines an extensible structure designed to support Modal Operation. An Unstructured VDM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. The Message format Shall be as shown in Figure 6.15, "Vendor Defined Message". Figure 6.15 Vendor Defined Message The VDM Header Shall be the first 4-byte object in a Vendor Defined Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. Additionally, vendors May make use of the Commands in a Structured VDM. The fields in the VDM Header for an Unstructured VDM, when the VDM Type Bit is set to zero, Shall be as defined in Table 6.28, "Unstructured VDM Header". The fields in the VDM Header for a Structured VDM, when the VDM Type Bit is set to one Shall be as defined in Table 6.29, "Structured VDM Header". Both Unstructured VDMs and Structured VDMs Shall only be sent and received after an Explicit Contract has been established. The only exception to this is the Discover Identity Command which May be sent by Source when a Default Contract or an Implicit Contract (in place after Attach, a Power Role Swap or Fast Role Swap) is in place in order to discover Cable Capabilities (see SSection 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 6.4.4.1 Unstructured VDM The Unstructured VDM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the VID. The Port Partners and Cable Plugs Shall exit any states entered using an Unstructured VDM when a Hard Reset appears on PD. The following rules apply to the use of Unstructured VDM Messages:  Unstructured VDMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract Unstructured VDMs Shall Not be sent and Shall be Ignored if received.  Only the DFP Shall be an Initiator of Unstructured VDMs.  Only the UFP or a Cable Plug Shall be a Responder to Unstructured VDM.  Unstructured VDMs Shall Not be initiated or responded to under any other circumstances. Header No. of Data Objects = 1-7 VDM Header 0-6 VDOs Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 163  Unstructured VDMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can Unstructured VDMs be sent or received. The Active Mode and the associated Unstructured VDMs Shall use the same SVID.  Unstructured VDMs May be used with SOP* Packets.  When a DFP or UFP does not support Unstructured VDMs or does not recognize the VID it Shall return a Not_Supported Message. Table 6.28, "Unstructured VDM Header" illustrates the VDM Header bits. 6.4.4.1.1 USB Vendor ID The Vendor ID (VID) field Shall contain the 16-bit Vendor ID value assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. 6.4.4.1.2 VDM Type The VDM Type field Shall be set to zero indicating that this is an Unstructured VDM. 6.4.4.2 Structured VDM Setting the VDM Type field to 1 (Structured VDM) defines the use of bits B14…0 in the Structured VDM Header. The fields in the Structured VDM Header are defined in Table 6.29, "Structured VDM Header". The following rules apply to the use of Structured VDM Messages:  Structured VDMs Shall only be used when an Explicit Contract is in place with the following exception:  Prior to establishing the First Explicit Contract, a Source May issue Discover Identity Messages, to a Cable Plug using SOP’ Packets, as an Initiator (see Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram").  Either Port May be an Initiator of Structured VDMs except for the Enter Mode and Exit Mode Commands which Shall only be initiated by the DFP.  A Cable Plug Shall only be a Responder to Structured VDMs.  Structured VDMs Shall Not be initiated or responded to under any other circumstances.  When a DFP or UFP does not support Structured VDMs any Structured VDMs received Shall return a Not_Supported Message.  When using any of the SVID Specific Commands in the Structured VDM Header (VDM Header b4…0 - value 16 - 31) the Responder Shall NAK Messages where the SVID in the VDM Header is not recognized as an SVID that uses SVID Specific Commands or the use of SVID Specific Commands is not supported for the SVID.  When a Cable Plug does not support Structured VDMs any Structured VDMs received Shall be Ignored. Table 6.28 Unstructured VDM Header Bit(s) Parameter Description B31…16 Vendor ID (VID) Unique 16-bit unsigned integer. Assigned by the USB-IF to the Vendor. B15 VDM Type 0 = Unstructured VDM B14…0 Available for Vendor Use Content of this field is defined by the vendor. Page 164 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A DFP, UFP or Cable Plug which supports Structured VDMs and receiving a Structured VDM for a SVID that it does not recognize Shall reply with a NAK Command. Table 6.29 Structured VDM Header Bit(s) Field Description B31…16 Standard or Vendor ID (SVID) Unique 16-bit unsigned integer, assigned by the USB-IF B15 VDM Type 1 = Structured VDM B14…13 Structured VDM Version (Major) Version Number (Major) of the Structured VDM (not this specification Version):  Version 1.0 = 00b (Deprecated and Shall Not be used)  Version 2.x = 01b  Values 2-3 are Reserved and Shall Not be used B12…11 Structured VDM Version (Minor) For Commands 0…15 Version Number (Minor) of the Structured VDM  Version 2.0 = 00b (Used for ports implemented prior to USB PD Revision 3.1, Version 1.6)  Version 2.1 = 01b (Used for ports implemented starting with USB PD Revision 3.1, Version 1.6)  All other Values are Reserved and Shall Not be used  SVID Specific Commands (16…31) defined by the SVID. B10…8 Object Position For the Enter Mode, Exit Mode, and Attention Commands (Requests/ Responses):  000b = Reserved and Shall Not be used.  001b…110b = Index into the list of VDOs to identify the desired Alternate Mode VDO  111b = Exit all Active Modes (equivalent of a power on reset). Shall  only be used with the Command. Commands 0…3, 7…15:  000b  001b…111b = Reserved and Shall Not be used. SVID Specific Commands (16…31) defined by the SVID. B7…6 Command Type 00b = REQ (Request from Initiator Port) 01b = ACK (Acknowledge Response from Responder Port) 10b = NAK (Negative Acknowledge Response from Responder Port) 11b = BUSY (Busy Response from Responder Port) B5 Reserved Shall be set to zero and Shall be Ignored B4…01 Command 0 = Reserved and Shall Not be used. 1 = Discover Identity 2 = Discover SVIDs 3 = Discover Modes 4 = Enter Mode 5 = Exit Mode 6 = Attention 7-15 = Reserved and Shall Not be used. 16…31 = SVID Specific Commands 1) In the case where a SID is used the modes are defined by a standard. When a VID is used the modes are defined by the Vendor. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 165 Section Table 6.30, "Structured VDM Commands" shows the Commands, which SVID to use with each Command and the SOP* values which Shall be used. 6.4.4.2.1 SVID The Standard or Vendor ID (SVID) field Shall contain either a 16-bit USB Standard ID value (SID) or the 16-bit assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. Section Table 6.31, "SVID Values" lists specific SVID values referenced by this specification. 6.4.4.2.2 VDM Type The VDM Type field Shall be set to one indicating that this is a Structured VDM. 6.4.4.2.3 Structured VDM Version The Structured VDM Version (Major)/Structured VDM Version (Minor) fields indicate the level of functionality supported in the Structured VDM part of the specification. This is not the same Version as the Version of this specification. The Structured VDM Version (Major) Shall be set to 01b to indicate Version 2.x with the Structured VDM Version (Minor) field set as appropriate based on whether the Port is implemented to USB PD Revision 3.1, Version 1.6 (or newer) or a prior Version. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every Structured VDM Version number starting from Version 1.0. On receipt of a VDM Header with a higher Version number than it supports, a Port or Cable Plug Shall respond using the highest Version number it supports. On receipt of a VDM Header with a lower Version number than it supports, a Port or Cable Plug Shall respond using the same Version number it received. The Structured VDM Version (Major)/Structured VDM Version (Minor) fields of the Discover Identity Command sent and received during the Discovery Process Shall be used to determine the lowest common Structured VDM Version supported by the Port Partners or Cable Plug and Shall continue to operate using this Specification Revision until they are Detached. After discovering the Structured VDM Version, the Structured VDM Version (Major)/ Structured VDM Version (Minor) fields Shall match the agreed common Structured VDM Version. Table 6.30 Structured VDM Commands Command VDM Header SVID Field SOP* used Discover Identity Shall only use the PD SID. Shall only use SOP/SOP’. Discover SVIDs Shall only use the PD SID. Shall only use SOP/SOP’. Discover Modes Valid with any SVID. Shall only use SOP/SOP’. Enter Mode Valid with any SVID. Valid with SOP*. Exit Mode Valid with any SVID. Valid with SOP*. Attention Valid with any SVID. Valid with SOP*. SVID Specific Commands Valid with any SVID. Valid with SOP* (defined by SVID). Table 6.31 SVID Values Parameter Value Description PD SID 0xFF00 Standard ID allocated to this specification by USB-IF. DPTC SID 0xFF01 Standard ID allocated to [DPTC2.1] by USB-IF. Page 166 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.2.4 Object Position The Object Position field Shall be used by the Enter Mode and Exit Mode Commands. The Discover Modes Command returns a list of zero to six VDOs, each of which describes an Alternate Mode. The value in Object Position field is an index into that list that indicates which VDO (e.g., Alternate Mode) in the list the Enter Mode and Exit Mode Command refers to. The Object Position Shall start with one for the first Alternate Mode in the list. If the SVID is a VID, the content of the VDO for the Alternate Mode Shall be defined by the vendor. If the Standard or Vendor ID (SVID) is a SID, the value Shall be assigned, by the USB-IF, to the given Standard. The VDO's content May be as simple as a numeric value or as complex as bit mapped description of Capabilities of the Alternate Mode. In all cases, the Responder is responsible for deciphering the contents to know whether or not it supports the Alternate Mode at the Object Position. This field Shall be set to zero in the Request or Response (REQ, ACK, NAK or BUSY) when not required by the specification of the individual Command. 6.4.4.2.5 Command Type 6.4.4.2.5.1 Commands other than Attention This Command Type field Shall be used to indicate the type of Command request/response being sent. An Initiator Shall set the Command Type field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then the responses are as follows:  "Responder ACK" is the normal return and Shall be sent to indicate that the Command request was received and handled normally.  "Responder NAK" Shall be returned when the Command request:  Has an Invalid parameter (e.g., Invalid SVID or Alternate Mode).  Cannot be acted upon because the configuration is not correct (e.g., an Alternate Mode which has a dependency on another Alternate Mode or a request to exit an Alternate Mode which is not anActive Mode).  Is an Unrecognized Message.  The handling of "Responder NAK" is left up to the Initiator.  "Responder BUSY" Shall be sent in the response to a VDM when the Responder is unable to respond to the Command request immediately, but the Command request May be retried. The Initiator Shall wait tVDMBusy after a "Responder BUSY" response is received before retrying the Command request. 6.4.4.2.5.2 Attention Command This Command Type field Shall be used to indicate the type of Command request being sent. An Initiator Shall set the field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then no response Shall be made to an Attention Command. 6.4.4.2.6 Command 6.4.4.2.6.1 Commands other than Attention The Command field contains the value for the VDM Command being sent. The Commands explicitly listed in the Command field are used to identify devices and manage their operational Modes. There is a further range of Command values left for the vendor to use to manage additional extensions. A Structured VDM Command consists of a Command request and a Command response (ACK, NAK or BUSY). A Structured VDM Command is deemed to be completed (and if applicable, the transition to the requested functionality is made) when the GoodCRC Message has been successfully received by the Responder in reply to its Command response. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 167 If Structured VDMs are supported, but the Structured VDM Command request is an Unrecognized Message, it Shall be NAKed (see Table 6.32, "Commands and Responses"). 6.4.4.2.6.2 Attention Command The Command field contains the value for the VDM Command being sent (Attention). The Attention Command May be used by the Initiator to notify the Responder that it requires service. A Structured VDM Attention Command consists of a Command request but no Command response. A Structured VDM Attention Command is deemed to be completed when the GoodCRC Message has been successfully received by the Initiator in reply to its Attention Command request. If Structured VDMs are supported, but the Structured VDM Attention Command request is an Unrecognized Message it Shall be Ignored (see Table 6.32, "Commands and Responses"). 6.4.4.3 Use of Commands The VDM Header for a Structured VDM Message defines Commands used to retrieve a list of SVIDs the device supports, to discover the Modes associated with each SVID, and to enter/exit the Modes. The Commands include:  Discover Identity  Discover SVIDs  Discover Modes  Enter Mode  Exit Mode  Attention Additional Command space is also Reserved for Standard and Vendor use and for future extensions. The Command AMSs use the terms Initiator and Responder to identify messaging roles the ports are taking on relative to each other. This role is independent of the Port's power capability (Provider, Consumer etc.) or its present Power Role (Source or Sink). The Initiator is the Port sending the initial Command request and the Responder is the Port replying with the Command response. See Section 6.4.4.4, "Command Processes". All Ports that support Modes Shall support the Discover Identity, Discover SVIDs, the Discover Modes, the Enter Mode and Exit Mode Commands. Table 6.32, "Commands and Responses" details the responses a Responder May issue to each Command request. Responses not listed for a given Command Shall Not be sent by a Responder. A NAK response Should be taken as an indication not to retry that particular Command. Examples of Command usage can be found in Appendix C, "VDM Command Examples". Table 6.32 Commands and Responses Command Allowed Response Reference Discover Identity ACK, NAK, BUSY Section 6.4.4.3.1 Discover SVIDs ACK, NAK, BUSY Section 6.4.4.3.2 Discover Modes ACK, NAK, BUSY Section 6.4.4.3.3 Enter Mode ACK, NAK Section 6.4.4.3.4 Exit Mode ACK, NAK Section 6.4.4.3.5 Attention None Section 6.4.4.3.6 Page 168 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1 Discover Identity The Discover Identity Command is provided to enable an Initiator to identify its Port Partner and for an Initiator (VCONN Source) to identify the Responder (Cable Plug or VPD). The Discover Identity Command is also used to determine whether a Cable Plug or VPD is PD-Capable by looking for a GoodCRC Message Response. The Discover Identity Command Shall only be sent to SOP when there is an Explicit Contract. The Discover Identity Command Shall be used to determine whether a given Cable Plug or VPD is PD Capable (see Section 8.3.3.21.1, "Initiator Structured VDM Discover Identity State Diagram" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). In this case a Discover Identity Command request sent to SOP’ Shall Not cause a Soft Reset if a GoodCRC Message response is not returned since this can indicate a non-PD Capable cable or VPD. Note: A Cable Plug or VPD will not be ready for PD Communication until tVCONNStable after VCONN has been applied (see [USB Type-C 2.4]). During Cable Plug or VPD discovery, when there is an Explicit Contract, Discover Identity Commands are sent at a rate defined by the DiscoverIdentityTimer (see Section 6.6.15, "DiscoverIdentityTimer") up to a maximum of nDiscoverIdentityCount times (see Section 6.7.5, "Discover Identity Counter"). A PD-Capable Cable Plug or VPD Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP’. The Discover Identity Command Shall be used to determine the identity and/or Capabilities of the Port Partner. The following products Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP:  A PD-Capable UFP that supports Modal Operation.  A PD-Capable product that has multiple DFPs.  A PD-Capable [USB4] product. The SVID in the Discover Identity Command request Shall be set to the PD SID (see Section Table 6.31, "SVID Values"). The Number of Data Objects field in the Message Header in the Discover Identity Command request Shall be set to 1 since the Discover Identity Command request Shall Not contain any VDOs. The Discover Identity Command ACK sent back by the Responder Shall contain an ID Header VDO, a Cert Stat VDO, a Product VDO and the Product Type VDOs defined by the Product Type as shown in Figure 6.16, "Discover Identity Command response". This specification defines the following Product Type VDOs:  Passive Cable VDO (see Section 6.4.4.3.1.6, "Passive Cable VDO")  Active Cable VDOs (see Section 6.4.4.3.1.7, "Active Cable VDOs")  VCONN Powered USB Device (VPD) VDO (see Section 6.4.4.3.1.9, "VCONN Powered USB Device VDO")  UFP VDO (see Section 6.4.4.3.1.4, "UFP VDO")  DFP VDO (see Section 6.4.4.3.1.5, "DFP VDO") No VDOs other than those defined in this specification Shall be sent as part of the Discover Identity Command response. Where there is no Product Type VDO defined for a specific Product Type, no VDOs Shall be sent as part of the Discover Identity Command response. Any additional VDOs received by the Initiator Shall be Ignored. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 169 Figure 6.16 Discover Identity Command response The Number of Data Objects field in the Message Header in the Discover Identity Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the product is a DRD both a Product Type (UFP) and a Product Type (DFP) are declared in the ID Header. These products Shall return Product Type VDOs for both UFP and DFP beginning with the UFP VDO, then by a 32-bit Pad Object (defined as all '0's), followed by the DFP VDO as shown in Figure 6.17, "Discover Identity Command response for a DRD". Figure 6.17 Discover Identity Command response for a DRD 6.4.4.3.1.1 ID Header VDO The ID Header VDO contains information corresponding to the Power Delivery Product. The fields in the ID Header VDO Shall be as defined in Section Table 6.33, "ID Header VDO". Table 6.33 ID Header VDO Bit(s) Description Reference B31 USB Communications Capable as USB Host Section 6.4.4.3.1.1.1  Shall be set to one if the product is capable of enumerating USB Devices.  Shall be set to zero otherwise. B30 USB Communications Capable as a USB Device Section 6.4.4.3.1.1.2  Shall be set to one if the product is capable of being enumerated as a USB Device.  Shall be set to zero otherwise B29…27 SOP Product Type (UFP) Section 6.4.4.3.1.1.3  000b – Not a UFP  001b – PDUSB Hub  010b – PDUSB Peripheral  011b – PSD  100b…111b – Reserved, Shall Not be used. SOP’ Product Type (Cable Plug/VPD)  000b – Not a Cable Plug/VPD  001b…010b – Reserved, Shall Not be used.  011b – Passive Cable  100b – Active Cable  101b – Reserved, Shall Not be used.  110b – VCONN Powered USB Device (VPD)  111b – Reserved, Shall Not be used. Header No. of Data Objects = 4-71 VDM Header ID Header VDO Cert Stat VDO 0..32 Product Type VDO(s) Product VDO 1. Only Data objects defined in this specification can be sent as part of the Discover Identity Command. 2. The following sections define the number and content of the VDOs for each Product Type. Header No. of Data Objects = 7 VDM Header ID Header VDO Cert Stat VDO Product VDO Product Type VDO(s) yp ( ) UFP Pad DFP Page 170 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.1 USB Communications Capable as a USB Host The USB Communications Capable as USB Host field is used to indicate whether or not the Port has a USB Host Capability. 6.4.4.3.1.1.2 USB Communications Capable as a USB Device The USB Communications Capable as a USB Device field is used to indicate whether or not the Port has a USB Device Capability. 6.4.4.3.1.1.3 Product Type (UFP) The SOP Product Type (UFP) field indicates the type of Product when in UFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP Product Type (UFP) field Shall be the closest categorization of the main functionality of the Product in UFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in UFP role regardless of the present Data Role. Table 6.34, "Product Types (UFP)" defines the Product Type VDOs which Shall be returned. B26 Modal Operation Supported Section 6.4.4.3.1.1.4  Shall be set to one if the product (UFP/Cable Plug) is capable of supporting Modal Operation (Alternate Modes).  Shall be set to zero otherwise. B25…23 SOP - Product Type (DFP) Section 6.4.4.3.1.1.6  000b – Not a DFP  001b – PDUSB Hub  010b – PDUSB Host  011b – Power Brick  100b…111b – Reserved, Shall Not be used. SOP’: Reserved, Shall Not be used. B22…21 Connector Type Section 6.4.4.3.1.1.7  00b – Reserved, for compatibility with legacy systems.  01b – Reserved, Shall Not be used.  10b – USB Type-C Receptacle  11b – USB Type-C Plug B20…16 Reserved, Shall Not be used. B15…0 USB Vendor ID Section 6.4.4.3.1.1.8 [USB 2.0]/[USB 3.2]/[USB4] Table 6.34 Product Types (UFP) Product Type Description Product Type VDO Reference Undefined Shall be used when this is not a UFP. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PDUSB Peripheral Shall be used when the Product is a PDUSB Device other than a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PSD Shall be used when the Product is a PSD, e.g., power bank. None Table 6.33 ID Header VDO (Continued) Bit(s) Description Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 171 6.4.4.3.1.1.4 Product Type (Cable Plug) The SOP’ Product Type (Cable Plug/VPD) field indicates the type of Product when the Product is a Cable Plug or VPD, whether a VDO will be returned and if so the type of VDO to be returned. Table 6.35, "Product Types (Cable Plug/ VPD)" defines the Product Type VDOs which Shall be returned. 6.4.4.3.1.1.5 Modal Operation Supported The Modal Operation Supported bit is used to indicate whether or not the Product (either a Cable Plug or a device that can operate in the UFP role) is capable of supporting Modes. The Modal Operation Supported bit does not describe a DFP's Alternate Mode Controller functionality. A product that supports Modal Operation Shall respond to the Discover SVIDs Command with a list of SVIDs for all of the Modes it is capable of supporting whether or not those Modes can currently be entered. 6.4.4.3.1.1.6 Product Type (DFP) The SOP - Product Type (DFP) field indicates the type of Product when in DFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP - Product Type (DFP) field Shall be the closest categorization of the main functionality of the Product in DFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in DFP role regardless of the present Data Role. Table 6.36, "Product Types (DFP)" defines the Product Type VDOs which Shall be returned. In SOP’ Communication (Cable Plugs and VPDs) this bit field is Reserved and Shall be set to zero. 6.4.4.3.1.1.7 Connector Type Field The Connector Type field (B22…21) Shall contain a value identifying it as either a USB Type-C receptacle or a USB Type-C plug. Table 6.35 Product Types (Cable Plug/VPD) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None Active Cable Shall be used when the Product is a cable that incorporates signal conditioning circuits. Active Cable VDO Section 6.4.4.3.1.7 Passive Cable Shall be used when the Product is a cable that does not incorporate signal conditioning circuits. Passive Cable VDO Section 6.4.4.3.1.6 VCONN Powered USB Device Shall be used when the Product is a PDUSB VCONN Powered USB Device. VPD VDO Section 6.4.4.3.1.9 Table 6.36 Product Types (DFP) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. DFP VDO Section 6.4.4.3.1.7 PDUSB Host Shall be used when the Product is a PDUSB Host or a PDUSB host that supports one or more Alternate Modes as an AMC. DFP VDO Section 6.4.4.3.1.6 Charger Shall be used when the Product is a Charger. DFP VDO Section 6.4.4.3.1.9 Page 172 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.8 Vendor ID Manufacturers Shall set the USB Vendor ID field to the value of the Vendor ID assigned to them by USB-IF. For USB Devices or Hubs which support USB Communications the USB Vendor ID field Shall be identical to the Vendor ID field defined in the product's USB Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.4.4.3.1.2 Cert Stat VDO The Cert Stat VDO Shall contain the XID assigned by USB-IF to the product before certification in binary format. The fields in the Cert Stat VDO Shall be as defined in Table 6.37, "Cert Stat VDO". 6.4.4.3.1.3 Product VDO The Product VDO contains identity information relating to the product. The fields in the Product VDO Shall be as defined in Table 6.38, "Product VDO". Manufacturers Should set the USB Product ID field to a unique value identifying the product and Should set the bcdDevice field to a version number relevant to the release version of the product. 6.4.4.3.1.4 UFP VDO The UFP VDO defined in this section Shall be returned by Ports capable of operating as a UFP including traditional USB peripherals, USB Hub's upstream Port and DRD capable host Ports. The UFP VDO defined in this section Shall be sent when the Product Type (UFP) field in the ID Header VDO is given as a PDUSB Peripheral or PDUSB Hub. Table 6.39, "UFP VDO" defines the UFP VDO that Shall be sent based on the Product Type. A [USB4] UFP Shall support the Structured VDM Discover Identity Command. Table 6.37 Cert Stat VDO Bit(s) Description Reference B31...0 32-bit unsigned integer, XID Assigned by USB-IF Table 6.38 Product VDO Bit(s) Description Reference B31...16 16-bit unsigned integer, USB Product ID [USB 2.0]/[USB 3.2] B15...0 16-bit unsigned integer, bcdDevice [USB 2.0]/[USB 3.2] Table 6.39 UFP VDO Bit(s) Description Reference B31…29 UFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.3 = 011b Values 100b…111b are Reserved, Shall Not be used. B28 Reserved Shall be set to zero. B27…24 Device Capability Bit Description 0 [USB 2.0] Device Capable 1 [USB 2.0] Device Capable (Billboard only) 2 [USB 3.2] Device Capable 3 [USB4] Device Capable B23…22 Connector Type (Legacy) Deprecated, Shall be set to 00b. B21…11 Reserved Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 173 6.4.4.3.1.4.1 VDO Version Field The UFP VDO Version field contains a VDO Version for this VDM Version number. This field indicates the expected content for the UFP VDOs. 6.4.4.3.1.4.2 Device Capability Field The Device Capability bit-field describes the UFP's Capabilities when operating as either a PDUSB Device or PDUSB Hub. B10…8 VCONN Power When the VCONN Required field is set to “Yes” the VCONN Power Field indicates the VCONN power needed by the AMA for full functionality:  000b = 1W  001b = 1.5W  010b = 2W  011b = 3W  100b = 4W  101b = 5W  110b = 6W 111b = Reserved, Shall Not be used. When the VCONN Required field is set to “No” the VCONN Power field is Reserved and Shall be set to zero. B7 VCONN Required Indicates whether the AMA requires VCONN in order to function.  0 = No  1 = Yes When the Alternate Modes field indicates no modes are supported, the VCONN Required field is Reserved and Shall be set to zero. B6 VBUS Required Indicates whether the AMA requires VBUS in order to function.  0 = Yes  1 = No When the Alternate Modes field indicates no modes are supported, the VBUS Required field is Reserved and Shall be set to zero. B5…3 Alternate Modes Bit Description 0 Supports [TBT3] Alternate Mode 1 Supports Alternate Modes that reconfigure the signals on the [USB Type-C 2.4] connector – except for [TBT3]. 2 Supports Alternate Modes that do not reconfigure the signals on the [USB Type-C 2.4] connector. B2…0 USB Highest Speed  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b =[USB4] Gen4  101b…111b = Reserved and Shall be set to zero. Table 6.39 UFP VDO (Continued) Bit(s) Description Reference Page 174 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The bits in the bit-field Shall be non-zero when the corresponding USB Device speed is supported and Shall be set to zero when the corresponding USB Device speed is not supported. [USB 2.0] "Device capable" and "Device capable Billboard only" (bits 0 and 1) Shall Not be simultaneously set. 6.4.4.3.1.4.3 Connector Type Field Th Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.4.4 VCONN Power Field When the VCONN Required field indicates that VCONN is required the VCONN Power field Shall indicate how much power an AMA needs in order to fully operate. When the VCONN Required field is set to "No" the VCONN Power field is Reserved and Shall be set to zero. 6.4.4.3.1.4.5 VCONN Required Field The VCONN Required field Shall indicate whether VCONN is needed for the AMA to operate. The VCONN Required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.6 VBUS Required Field The VBUS Required field Shall indicate whether VBUS is needed for the AMA to operate. The VBUS required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.7 Alternate Modes Field The Alternate Modes field Shall be used to identify all the types of Alternate Modes, if any, a device supports. 6.4.4.3.1.4.8 USB Highest Speed Field The USB Highest Speed field Shall indicate the Port's highest speed capability. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 175 6.4.4.3.1.5 DFP VDO The DFP VDO Shall be returned by Ports capable of operating as a DFP; including those implemented by Hosts, Hubs and Power Bricks. The DFP VDO Shall be returned when the Product Type (DFP) field in the ID Header VDO is given as Power Brick, PDUSB Host or PDUSB Hub. Table 6.40, "DFP VDO" defines the DFP VDO that Shall be sent. 6.4.4.3.1.5.1 VDO Version Field The DFP VDO Version field Shall contain a VDO Version for this VDM Version number. This field indicates the expected content for the DFP VDO. 6.4.4.3.1.5.2 Host Capability Field The Host Capability bit-field Shall describe whether the DFP can operate as a PDUSB Host and the DFP's Capabilities when operating as a PDUSB Host. Power Bricks and PDUSB Hubs Shall set the Host Capability bits to zero. 6.4.4.3.1.5.3 Connector Type Field The Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.5.4 Port Number Field The Port Number field Shall be a Static unique number that unambiguously identifies each [USB Type-C 2.4] DFP, including DRPs, on the device. Note: This number is independent of the USB Port number. Table 6.40 DFP VDO Bit(s) Field Description B31…29 DFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.2 = 010b Values 011b…111b are Reserved and Shall Not be used B28…27 Reserved Shall be set to zero. B26…24 Host Capability Bit Description 0 [USB 2.0] Host Capable 1 [USB 3.2] Host Capable 2 [USB4] Host Capable B23…22 Connector Type (Legacy) Shall be set to 00b. B21…5 Reserved Shall be set to zero. B4…0 Port Number Unique Port number to identify a specific Port on a multi-Port device. Page 176 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.6 Passive Cable VDO The Passive Cable VDO defined in this section Shall be sent when the Product Type is given as Passive Cable. Table 6.41, "Passive Cable VDO" defines the Cable VDO which Shall be sent. A Passive Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. A Passive Cable Shall Not incorporate data bus signal conditioning circuits and hence has no concept of Super Speed Directionality. A Passive Cable Shall include a VBUS wire and Shall only respond to SOP’ Communication. Passive Cables Shall support the Structured VDM Discover Identity Command and Shall return the Passive Cable VDO in a Discover Identity Command ACK as shown in Table 6.41, "Passive Cable VDO". Table 6.41 Passive Cable VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive (Passive Cable)  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Passive Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency (Passive Cable)  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b – > 70ns (>~7m) Note: 1001b ….1111b Reserved and Shall Not be used B12…11 Cable Termination Type (Passive Cable)  00b = VCONN not required. Cable Plugs that only support Discover Identity Commands Shall set these bits to 00b.  01b = VCONN required  10b…11b = Reserved and Shall Not be used B10…9 Maximum VBUS Voltage (Passive Cable) Maximum Cable VBUS Voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 177 6.4.4.3.1.6.1 HW Version Field The HW Version (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.6.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.6.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.6.4 USB Type-C plug to USB Type-C/Captive Field The USB Type-C plug to USB Type-C/Captive (Passive Cable) field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.6.5 EPR Mode Capable The EPR Capable (Passive Cable) bit is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.6.6 Cable Latency Field The Cable Latency (Passive Cable) field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. 6.4.4.3.1.6.7 Cable Termination Type Field The Cable Termination Type (Passive Cable) field (B12…11) Shall contain a value indicating whether the Passive Cable needs VCONN only initially in order to support the Discover Identity Command, after which it can be removed, or the Passive Cable needs VCONN to be continuously applied in order to power some feature of the Cable Plug. 6.4.4.3.1.6.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Passive Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated using a Fixed Supply over the cable as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage (Passive Cable) field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Passive B6…5 VBUS Current Handling Capability (Passive Cable)  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4…3 Reserved Shall be set to zero. B2…0 USB Highest Speed (Passive Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.41 Passive Cable VDO (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 178 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Passive Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.6.9 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Passive Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. 6.4.4.3.1.6.10 USB Highest Speed Field The USB Highest Speed (Passive Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 179 6.4.4.3.1.7 Active Cable VDOs An Active Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. An Active Cable Shall incorporate data bus signal conditioning circuits and May have a concept of Super Speed Directionality on its Super Speed wires. An Active Cable May include a VBUS wire. An Active Cable:  Shall respond to SOP’ Communication.  May respond to SOP’’ Communication.  Shall support the Structured VDM Discover Identity Command.  In the Discover Identity Command ACK:  Shall set the Product Type in the ID Header VDO to Active Cable.  Shall return the Active Cable VDOs defined in Table 6.42, "Active Cable VDO1" and Table 6.43, "Active Cable VDO2".. Table 6.42 Active Cable VDO1 Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Active Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b –1000ns (~100m)  1001b –2000ns (~200m)  1010b – 3000ns (~300m)  1001b ….1111b Reserved and Shall Not be used Note: Includes latency of electronics in Active Cable. B12…11 Cable Termination Type (Active Cable)  00b…01b = Reserved and Shall Not be used  10b = One end Active, one end passive, VCONN required  11b = Both ends Active, VCONN required 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 180 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 B10…9 Maximum VBUS Voltage (Active Cable) Maximum Cable VBUS voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. B8 SBU Supported  0 = SBU connections supported  1 = SBU connections are not supported B7 SBU Type When SBU Supported = 1 this bit Shall be Ignored When SBU Supported = 0:  0 = SBU is passive  1 = SBU is active B6…5 VBUS Current Handling Capability (Active Cable) When VBUS Through Cable is “No”, this field Shall be Ignored. When VBUS Through Cable is “Yes”:  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4 VBUS Through Cable  0 = No  1 = Yes B3 SOP’’ Controller Present  0 = No SOP’’ controller present  1 = SOP’’ controller present B2…0 USB Highest Speed (Active Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.43 Active Cable VDO2 Bit(s) Field Description B31…24 Maximum Operating Temperature The maximum internal operating temperature in °C. It might or might not reflect the plug’s skin temperature. B23…16 Shutdown Temperature The temperature, in °C, at which the cable will go into thermal shutdown so as not to exceed the allowable plug skin temperature. B15 Reserved Shall be set to zero. B14…12 U3/CLd Power  000b: >10mW  001b: 5-10mW  010b: 1-5mW  011b: 0.5-1mW  100b: 0.2-0.5mW  101b: 50-200µW  110b: <50µW  111b: Reserved and Shall Not be used Table 6.42 Active Cable VDO1 (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 181 6.4.4.3.1.7.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.7.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.7.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for the Active Cable VDOs. 6.4.4.3.1.7.4 Connector Type Field The USB Type-C plug to USB Type-C/Captive field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.7.5 EPR Mode Capable The EPR Capable (Active Cable) is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.7.6 Cable Latency Field The Cable Latency field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. B11 U3 to U0 transition mode  0b: U3 to U0 direct  1b: U3 to U0 through U3S B10 Physical connection  0b = Copper  1b = Optical B9 Active element  0b = Active Re-driver  1b = Active Re-timer B8 USB4 Supported  0b = [USB4] supported  1b = [USB4]not supported B7…6 USB 2.0 Hub Hops Consumed Number of [USB 2.0] ‘hub hops’ cable consumes. Shall be set to zero if USB 2.0 not supported. B5 USB 2.0 Supported  0b = [USB 2.0] supported  1b = [USB 2.0] not supported B4 USB 3.2 Supported  0b = [USB 3.2] SuperSpeed supported  1b = [USB 3.2] SuperSpeed not supported B3 USB Lanes Supported  0b = One lane  1b = Two lanes B2 Optically Isolated Active Cable  0b = No  1b = Yes B1 USB4 Asymmetric Mode Supported  0b = No  1b = Yes Shall be set to zero if asymmetry is not supported. B0 USB Gen  0b = Gen 1  1b = Gen 2 or higher Note: See VDO1 USB Highest Speed for details of Gen supported. Table 6.43 Active Cable VDO2 (Continued) Bit(s) Field Description Page 182 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.7.7 Cable Termination Type Field The Cable Termination Type (Active Cable) field (B12…11) Shall contain a value corresponding to whether the Active Cable has one or two Cable Plugs requiring power from VCONN. 6.4.4.3.1.7.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Active Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. When this field is set to 20V, the cable will safely carry a Programmable Power Supply APDO of 20V where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Active Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Active Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.7.9 SBU Supported Field The SBU Supported field (B8) Shall indicate whether the cable supports the SBUs in the cable. 6.4.4.3.1.7.10 SBU Type Field The SBU Type field (B7) Shall indicate whether the SBUs are passive or active (e.g., digital). 6.4.4.3.1.7.11 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Active Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. The VBUS Current Handling Capability (Active Cable) field Shall only be Valid when the VBUS Current Handling Capability (Active Cable) field indicates an end-to-end VBUS wire. 6.4.4.3.1.7.12 VBUS Through Cable Field The VBUS Through Cable field (B4) Shall indicate whether the cable contains an end-to-end VBUS wire. 6.4.4.3.1.7.13 SOP'' Controller Present Field The SOP’’ Controller Present field (B3) Shall indicate whether one of the Cable Plugs is capable of SOP’’ Communication in addition to the Normative SOP’ Communication. 6.4.4.3.1.7.14 USB Highest Speed Field The USB Highest Speed (Active Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. 6.4.4.3.1.7.15 Maximum Operating Temperature Field Maximum Operating Temperature field (B31…24) Shall report the maximum allowable operating temperature inside the plug in °C. 6.4.4.3.1.7.16 Shutdown Temperature Field Shutdown Temperature field (B23…16) Shall indicate the temperature inside the plug, in °C, at which the plug will shut down its active signaling components. When this temperature is reached, it will be reported in the Active Cable Status Message through the Thermal Shutdown bit. 6.4.4.3.1.7.17 U3/CLd Power Field The U3/CLd Power field (B14…12) Shall indicate the power the cable consumes while in [USB 3.2] U3 or [USB4] CLd. 6.4.4.3.1.7.18 U3 to U0 Transition Mode Field The U3 to U0 transition mode field (B11) Shall indicate which U3 to U0 mode the cable supports. This does not include the power in U3S if supported. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 183 6.4.4.3.1.7.19 Physical Connection Field The Physical connection field (B10) Shall indicate the cable's construction, whether the connection between the active elements is copper or optical. 6.4.4.3.1.7.20 Active element Field The Active element field (B9) Shall indicate the cable's active element, whether the active element is a re-timer or a re-driver. 6.4.4.3.1.7.21 USB4 Supported Field The USB4 Supported field (B8) Shall indicate whether or not the cable supports [USB4] operation. 6.4.4.3.1.7.22 USB 2.0 Hub Hops Consumed field The USB 2.0 Hub Hops Consumed field (B7…6) Shall indicate the number of USB 2.0 'hub hops' that are lost due to the transmission time of the cable. 6.4.4.3.1.7.23 USB 2.0 Supported Field The USB 2.0 Supported field (B5) Shall indicate whether or not the cable supports [USB 2.0] only signaling. 6.4.4.3.1.7.24 USB 3.2 Supported Field The USB 3.2 Supported field (B4) Shall, indicate whether or not the cable supports [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.25 USB Lanes Supported Field The USB Lanes Supported field (B3) Shall indicate whether the cable supports one or two lanes of [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.26 Optically Isolated Active Cable Field The Optically Isolated Active Cable field (B2) Shall indicate whether this cable is an optically isolated Active Cable or not (as defined in [USB Type-C 2.4]). Optically Isolated Active Cables Shall have a re-timer or linear re-driver (LRD) as the active element and do not support [USB 2.0] or carry VBUS. 6.4.4.3.1.7.27 USB4 Asymmetric Mode Supported Field The USB4 Asymmetric Mode Supported field (B1) Shall indicate that the Active Cable supports asymmetric mode as defined in [USB4] and [USB Type-C 2.4]. 6.4.4.3.1.7.28 USB Gen Field The USB Gen field (B0) Shall indicate the signaling Gen the cable supports. Gen 1 Shall only be used by [USB 3.2] cables as indicated by the USB 3.2 Supported field. Gen 2 or higher May be used by either [USB 3.2] or [USB4] cables as indicated by their respective supported fields. When Gen 2 or higher is indicated the USB Highest Speed (Active Cable) field in VDO1 Shall indicate the actual Gen supported. 6.4.4.3.1.8 Alternate Mode Adapter VDO The Alternate Mode Adapter (AMA) VDO has been Deprecated. PDUSB Devices which support one or more Alternate Modes Shall set an appropriate Product Type (UFP), and Shall set the Modal Operation Supported bit to '1'. Page 184 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.9 VCONN Powered USB Device VDO The VCONN Powered USB Device (VPD) VDO defined in this section Shall be sent when the Product Type is given as VCONN Powered USB Device. Table 6.44, "VPD VDO" defines the VPD VDO which Shall be sent. 6.4.4.3.1.9.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.9.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.9.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.9.4 Maximum VBUS Voltage Field The Maximum VBUS Voltage field (B16…15) Shall contain the maximum voltage that a Sink Shall Negotiate through the VPD Charge Through Port as part of an Explicit Contract. Note: The maximum voltage that will be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Table 6.44 VPD VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b  Values 001b…111b are Reserved and Shall Not be used. B20...17 Reserved Shall be set to zero. B16…15 Maximum VBUS Voltage Maximum VPD VBUS Voltage:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V1 (Deprecated) B14 Charge Through Current Support Charge Through Current Support bit=1b:  0b - 3A capable.  1b - 5A capable Charge Through Current Support bit = 0b:  Reserved and Shall be set to zero. B13 Reserved Shall be set to zero. B12…7 VBUS Impedance Charge Through Current Support bit = 1b: VBUS impedance through the VPD in 2 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Reserved and Shall be set to zero. B6…1 Ground Impedance Charge Through Current Support bit = 1b: Ground impedance through the VPD in 1 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Shall be set to zero. B0 Charge Through Support  1b – the VPD supports Charge Through  0b – the VPD does not support Charge Through 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 185 Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Maximum VBUS Voltage field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.9.5 VBUS Impedance Field The VBUS Impedance field (B12…7) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the VBUS IR Drop limit of 0.5V between the Source and itself. If the Sink can tolerate a larger IR Drop on VBUS it May do so. 6.4.4.3.1.9.6 Ground Impedance Field The Ground Impedance field (B6…1) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the Ground IR Drop limit of 0.25V between the Source and itself. 6.4.4.3.1.9.7 Charge Through Field The Firmware Version field (B0) Shall be set to 1b when the VPD supports Charge Through and 0b otherwise. Page 186 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.2 Discover SVIDs The Discover SVIDs Command is used by an Initiator to determine the SVIDs for which a Responder has Modes. The Discover SVIDs Command is used in conjunction with the Discover Modes Command in the Discovery Process to determine which Modes a device supports. The list of SVIDs is always terminated with one or two 0x0000 SVIDs. The SVID in the Discover SVIDs Command Shall be set to the PD SID (see "Table 6.31, "SVID Values") by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover SVIDs Command request Shall be set to 1 since the Discover SVIDs Command request Shall Not contain any VDOs. The Discover SVIDs Command ACK sent back by the Responder Shall contain one or more SVIDs. The SVIDs are returned 2 per VDO (see Table 6.45, "Discover SVIDs Responder VDO"). If there are an odd number of supported SVIDs, the Discover SVIDs Command is returned ending with a SVID value of 0x0000 in the last part of the last VDO. If there are an even number of supported SVIDs, the Discover SVIDs Command is returned ending with an additional VDO containing two SVIDs with values of 0x0000. A Responder Shall only return SVIDs for which a Discover Modes Command request for that SVID will return at least one Alternate Mode. A Responder that does not support any SVIDs Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover SVIDs Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the Responder supports 12 or more SVIDs then the Discover SVIDs Command Shall be executed multiple times until a Discover SVIDs VDO is returned ending either with a SVID value of 0x0000 in the last part of the last VDO or with a VDO containing two SVIDs with values of 0x0000. Each Discover SVID ACK Message, other than the one containing the terminating 0x0000 SVID, Shall convey 12 SVIDs. The Responder Shall restart the list of SVIDs each time a Discover Identity Command request is received from the Initiator. Note: Since a Cable Plug does not retry Messages if the GoodCRC Message from the Initiator becomes corrupted the Cable Plug will consider the Discover SVIDs Command ACK unsent and will send the same list of SVIDs again. Figure 6.18, "Example Discover SVIDs response with 3 SVIDs" shows an example response to the Discover SVIDs Command request with two VDOs containing three SVIDs. Figure 6.19, "Example Discover SVIDs response with 4 SVIDs" shows an example response with two VDOs containing four SVIDs followed by an empty VDO to terminate the response. Figure 6.20, "Example Discover SVIDs response with 12 SVIDs followed by an empty response" shows an example response with six VDOs containing twelve SVIDs followed by an additional request that returns an empty VDO indicating there are no more SVIDs to return. Figure 6.18 Example Discover SVIDs response with 3 SVIDs Table 6.45 Discover SVIDs Responder VDO Bit(s) Field Description B31…16 SVID n 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an even number of SVIDs. B15…0 SVID n+1 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an odd or even number of SVIDs. Header No. of Data Objects = 3 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) 0x0000 (B15..0) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 187 Figure 6.19 Example Discover SVIDs response with 4 SVIDs Figure 6.20 Example Discover SVIDs response with 12 SVIDs followed by an empty response Header No. of Data Objects = 4 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 0x0000 (B31..16) 0x0000 (B15..0) Header No. of Data Objects = 7 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 SVID 4 (B31..16) SVID 5 (B15..0) VDO 4 SVID 6 (B31..16) SVID 7 (B15..0) VDO 5 SVID 8 (B31..16) SVID 9 (B15..0) Header No. of Data Objects = 2 VDM Header VDO 1 0x0000 (B31..16) 0x0000 (B15..0) VDO 6 SVID 10 (B31..16) SVID 11 (B15..0) Page 188 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.3 Discover Modes The Discover Modes Command is used by an Initiator to determine the Modes a Responder supports for a given SVID. The SVID in the Discover Modes Command Shall be set to the SVID for which Modes are being requested by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover Modes Command request Shall be set to 1 since the Discover Modes Command request Shall Not contain any VDOs. The Discover Modes Command ACK sent back by the Responder Shall contain one or more Modes. The Discover Modes Command ACK Shall contain a Message Header with the Number of Data Objects field set to a value of 2 to 7 (the actual value is the number of Alternate Mode objects plus one). If the ID is a VID, the structure and content of the VDO is left to the Vendor. If the ID is a SID, the structure and content of the VDO is defined by the relevant standard’s body. A Responder that does not support any Modes Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover Modes Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes" shows an example of a Discover Modes Command response from a Responder which supports three Modes for a given SVID. Figure 6.21 Example Discover Modes response for a given SVID with 3 Modes 6.4.4.3.4 Enter Mode Command The Enter Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to enter a specified Alternate Mode of operation. Only a DFP Shall initiate the Enter Mode Process which it starts after it has successfully completed the Discovery Process. The value in the Object Position field in the VDM Header Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes"). The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. The Number of Data Objects field in the Message Header in the Command request Shall be set to either 1 or 2 since the Enter Mode Command request Shall Not contain more than 1 VDO. When a VDO is included in an Enter Mode Command request the contents of the 32-bit VDO is defined by the Alternate Mode. The Number of Data Objects field in the Command response Shall be set to 1 since an Enter Mode Command response (ACK, NAK) Shall Not contain any VDOs. Before entering a Alternate Mode, by sending the Enter Mode Command request that requires the reconfiguring of any pins on entry to that Alternate Mode, the Initiator Shall ensure that those pins being reconfigured are placed into the USB Safe State. Before entering an Alternate Mode that requires the reconfiguring of any pins, the Responder Shall ensure that those pins being reconfigured are placed into either USB operation or the USB Safe State. A device May support multiple Modes with one or more active at any point in time. Any interactions between them are the responsibility of the Standard or Vendor. Where there are multiple Active Modes at the same time Modal Operation Shall start on entry to the first Alternate Mode. Header No. of Data Objects = 4 VDM Header Mode 1 Mode 2 Mode 3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 189 On receiving an Enter Mode Command requests the Responder Shall respond with either an ACK or a NAK response. The Responder is not allowed to return a BUSY response. The value in the Object Position field of the Enter Mode Command response Shall contain the same value as the received Enter Mode Command request. If the Responder responds to the Enter Mode Command request with an ACK, the Responder Shall enter the Alternate Mode before sending the ACK. The Initiator Shall enter the Alternate Mode on reception of the ACK. Successful transmission of the Message confirms to the Responder that the Initiator will enter an Active Mode. See Figure 8.111, "DFP to UFP Enter Mode" for more details. If the Responder responds to the Enter Mode Command request with a NAK, the Alternate Mode is not entered. If not presently in Modal Operation the Initiator Shall return to USB operation. If not presently in Modal Operation the Responder Shall remain in either USB operation or the USB Safe State. If the Initiator fails to receive a response within tVDMWaitModeEntry it Shall Not enter the Alternate Mode but return to USB operation. Figure 6.22, "Successful Enter Mode sequence" shows the sequence of events during the transition between USB operation and entering an Alternate Mode. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.23, "Unsuccessful Enter Mode sequence due to NAK" illustrates that when the Responder returns a NAK the transition to an Alternate Mode do not take place and the Responder and Initiator remain in their default USB roles. Figure 6.22 Successful Enter Mode sequence DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC ACK USB Safe State USB USB or USB Safe State New Mode New Mode Page 190 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.23 Unsuccessful Enter Mode sequence due to NAK Once the Alternate Mode is entered, the device Shall remain in that Active Mode until the Exit Mode Command is successful (see Section 6.4.4.3.5, "Exit Mode Command"). The following events Shall also cause the Port Partners and Cable Plug(s) to exit all Active Modes:  A PD Hard Reset.  Error Recovery.  The Port Partners or Cable Plug(s) are Detached.  A Cable Reset (only exits the Cable Plug's Active Modes).  A Data Reset (removing power briefly resets all the Active Modes in the Cable Plug). The Initiator Shall return to USB Operation within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. The Responder Shall return to either USB operation or USB Safe State within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. A DR_Swap Message Shall Not be sent during Modal Operation between the Port Partners (see Section 6.3.9, "DR_Swap Message"). 6.4.4.3.5 Exit Mode Command The Exit Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to exit its Active Mode and return to normal USB operation. Only the DFP Shall initiate the Exit Mode Process. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC NAK USB Safe State USB USB or USB Safe State USB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 191 Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 111b in the Object Position field Shall indicate that all Active Modes Shall be exited. The Number of Data Objects field in both the Command request and Command response (ACK, NAK) Shall be set to 1 since an Exit Mode Command Shall Not contain any VDOs. The Responder Shall exit its Active Mode before sending the response Message. The Initiator Shall exit its Active Mode when it receives the ACK. The Responder Shall Not return a BUSY acknowledgment and Shall only return a NAK acknowledgment to a request not containing an Active Mode (i.e., Invalid object position). An Initiator which fails to receive an ACK within tVDMWaitModeExit or receives a NAK or BUSY response Shall exit its Active Mode. See Figure 8.112, "DFP to UFP Exit Mode" for more details. Figure 6.24, "Exit Mode sequence" shows the sequence of events during the transition between exiting an Active Mode and USB operation. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.24 Exit Mode sequence 6.4.4.3.6 Attention The Attention Command May be used by the Initiator to notify the Responder that it requires service. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 000b or 111b in the Object Position field Shall Not be used by the Attention Command. DFP (Initiator) UFP (Responder) Exit Mode GoodCRC GoodCRC ACK USB Safe State USB or USB Safe State Mode Mode USB Page 192 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Number of Data Objects field in the Message Header Shall be set to 1 or 2 since the Attention Command Shall Not contain more than 1 VDO. When a VDO is included in an Attention Command the contents of the 32-bit VDO is defined by the Alternate Mode. Figure 6.24, "Exit Mode sequence" shows the sequence of events when an Attention Command is received. Figure 6.25 Attention Command request/response sequence 6.4.4.4 Command Processes The Message flow of Commands during a Process is a query followed by a response. Every Command request sent has to be responded to with a GoodCRC Message. The GoodCRC Message only indicates the Command request was received correctly; it does not mean that the Responder understood or even supports a particular SVID. Figure 6.26, "Command request/response sequence" shows the request/response sequence including the GoodCRC Messages. Initiator Responder GoodCRC Command (Attention) Command Complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 193 Figure 6.26 Command request/response sequence In order for the Initiator to know that the Command request was actually consumed, it needs an acknowledgment from the Responder. There are three responses that indicate the Responder received and processed the Command request:  ACK  NAK  BUSY The Responder Shall complete:  Enter Mode requests within tVDMEnterMode.  Exit Mode requests within tVDMExitMode.  Other requests within tVDMReceiverResponse. An Initiator not receiving a response within the following times Shall timeout and return to either the PE_SRC_Ready or PE_SNK_Ready state (as appropriate):  Enter Mode requests within tVDMWaitModeEntry.  Exit Mode requests within tVDMWaitModeExit.  Other requests within tVDMSenderResponse. The Responder Shall respond with:  ACK if it recognizes the SVID and can process it at this time.  NAK:  if it recognizes the SVID but cannot process the Command request Initiator Responder Command (request) GoodCRC GoodCRC Command (response) Command Complete Page 194 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  or if it does not recognize the SVID  or if it does not support the Command  or if a VDO contains a field which is Invalid.  BUSY if it recognizes the SVID and the Command but cannot process the Command request at this time. The ACK, NAK or BUSY response Shall contain the same SVID as the Command request. 6.4.4.4.1 Discovery Process The Initiator (usually the DFP) always begins the Discovery Process. The Discovery Process has two phases. In the first phase, the Discover SVIDs Command request is sent by the Initiator to get the list of SVIDs the Responder supports. In the second phase, the Initiator sends a Discover Modes Command request for each SVID supported by both the Initiator and Responder. 6.4.4.4.2 Enter Vendor Mode / Exit Vendor Mode Processes The result of the Discovery Process is that both the Initiator and Responder identify the Modes they mutually support. The Initiator (DFP), upon finding a suitable Alternate Mode, uses the Enter Mode Command to enable the Alternate Mode. The Responder (UFP or Cable Plug) and Initiator continue using the Active Mode until the Active Mode is exited. In a managed termination, using the Exit Mode Command, the Active Mode Shall be exited in a controlled manner as described in Section 6.4.4.3.5, "Exit Mode Command". In an unmanaged termination, triggered by:  A Power Delivery Hard Reset (i.e. Hard Reset Signaling sent by either Port Partner) or  By cable Detach (device unplugged) or  By Error Recovery the Active Mode Shall still be exited but there Shall Not be a transition through the USB Safe State. In both the managed and unmanaged terminations, the Initiator and Responder return to USB operation as defined in [USB Type-C 2.4] following an exit from an Alternate Mode. The overall Message flow is illustrated in Figure 6.27, "Enter/Exit Mode Process". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 195 Figure 6.27 Enter/Exit Mode Process 6.4.4.5 VDM Message Timing and Normal PD Messages The timing and interspersing of VDMs between regular PD Messages Shall be done without perturbing the PD AMSs. This requirement Shall apply to both Unstructured VDMs and Structured VDMs. Initiator (DFP) Responder (UFP or Cable Plug) Discover SVIDs List of SVIDs For every DFP supported SVID Modes Supported? N Stay in USB mode Y Enter Mode ACK (Responder switched to Mode) Initiator and Responder operate using Mode Return to USB mode Establish PD Contract Exit Mode or PD Hard Reset or cable unplugged or power removed? Y N USB USB or USB Safe State USB Safe State USB Alternate Mode USB or USB Safe State Alternate Mode USB Discover Modes (SVID) Modes for SVID Page 196 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The use of Structured VDMs by an Initiator Shall Not interfere with the normal PD Message timing requirements nor Shall either the Initiator or Responder interrupt a PD AMS (e.g., Negotiation, Power Role Swap, Data Role Swap etc.). The use of Unstructured VDMs Shall Not interfere with normal PD Message timing. 6.4.5 Battery_Status Message The Battery_Status Message Shall be sent in response to a Get_Battery_Status Message. The Battery_Status Message contains one Battery Status Data Object (BSDO) for one of the Batteries it supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BSDO Shall correspond to the Battery requested in the Battery Status Ref field contained in the Get_Battery_Status Message. The Battery_Status Message returns a BSDO whose format Shall be as shown in Figure 6.28, "Battery_Status Message" and Table 6.46, "Battery Status Data Object (BSDO)". The Number of Data Objects field in the Battery_Status Message Shall be set to 1. Figure 6.28 Battery_Status Message 6.4.5.1 Battery Present Capacity The Battery Present Capacity field Shall return either the Battery's State of Charge (SoC) in tenths of WH or indicate that the Battery's present State of Charge (SOC) is unknown. Table 6.46 Battery Status Data Object (BSDO) Bit(s) Field Description B31…16 Battery Present Capacity Battery’s State of Charge (SoC) in 0.1 WH increments Note: 0xFFFF = Battery’s SOC unknown B15…8 Battery Info Bit Description 0 Invalid Battery Reference Invalid Battery reference 1 Battery Present Battery is present when set 3…2 Battery Charging Status When Battery Present is ‘1’ Shall contain the Battery charging status:  00b: Battery is Charging.  01b: Battery is Discharging.  10b: Battery is Idle.  11b: Reserved, Shall Not be used. When Battery Present is ‘0’:  11b…00b: Reserved, Shall Not be used. 7…4 Reserved, Shall Not be used. B7…0 Reserved Shall be set to zero Header No. of Data Objects = 1 BSDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 197 6.4.5.2 Battery Info The Battery Info field Shall be used to report additional information about the Battery's present status. The Battery Info field's bits Shall reflect the present conditions under which the Battery is operating in the systems. 6.4.5.2.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Status Message contains a reference to a Battery or Battery Slot (see Section 6.5.1.13, "Number of Batteries/Battery Slots Field") that does not exist. 6.4.5.2.2 Battery Present The Battery Present bit Shall be set whenever the Battery is present. It Shall always be set for Batteries that are not Hot Swappable Batteries. For Hot Swappable Batteries, the Battery Present bit Shall indicate whether the Battery is Attached or Detached. 6.4.5.2.3 Battery Charging Status The Battery Charging Status bits indicate whether the Battery is being charged, discharged or is idle (neither charging nor discharging). These bits Shall be set when the Battery Present bit is set. Otherwise, when the Battery Present bit is zero the Battery Charging Status bits Shall also be zero. Page 198 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6 Alert Message The Alert Message is provided to allow Port Partners to inform each other when there is a status change event. Some of the events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Alert Message Shall only be sent when the Source or Sink detects a status change. The Alert Message Shall contain exactly one Alert Data Object (ADO) and the format Shall be as shown in Figure 6.29, "Alert Message" and Table 6.47, "Alert Data Object (ADO)". Figure 6.29 Alert Message Table 6.47 Alert Data Object (ADO) Bit(s) Field Description B31…24 Type of Alert Bit Description 0 Reserved and Shall be set to zero. 1 Battery Status Change Event Battery Status Change Event (Attach/Detach/charging/discharging/ idle) 2 OCP Event OCP event when set (Source only, for Sink Reserved and Shall be set to zero). 3 OTP Event OTP event when set 4 Operating Condition Change Operating Condition Change when set 5 Source Input Change Event Source Input Change Event when set 6 OVP Event OVP event when set 7 Extended Alert Event Extended Alert Event when set B23…20 Fixed Batteries When Battery Status Change Event bit set indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. B19…16 Hot Swappable Batteries When Battery Status Change Event bit set indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 4 and B19 corresponds to Battery 7. Header No. of Data Objects = 1 ADO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 199 6.4.6.1 Type of Alert The Type of Alert field Shall be used to report Source or Sink status changes. Only one Alert Message Shall be generated for each Event or Change; however multiple Type of Alert bits May be set in one Alert Message. Once the Alert Message has been sent the Type of Alert field Shall be cleared. A Get_Battery_Status Message Should be sent in response to a Battery status change in an Alert Message to get the details of the change. A Get_Status Message Should be sent in response to a non-Battery status change in an Alert Message from to get the details of the change. 6.4.6.1.1 Battery Status Change The Battery Status Change Event bit Shall be set when any Battery's power state changes between charging, discharging, neither. For Hot Swappable Batteries, it Shall also be set when a Battery is Attached or Detached. 6.4.6.1.2 Over-Current Protection Event The OCP Event bit Shall be set when a Source detects its output current exceeds its limits triggering its protection circuitry. This bit is Reserved for a Sink. 6.4.6.1.3 Over-Temperature Protection Event The OTP Event bit Shall be set when a Source or Sink shuts down due to over-temperature triggering its protection circuitry. 6.4.6.1.4 Operating Condition Change The Operating Condition Change bit Shall be set when a Source or Sink detects its Operating Condition enters or exits either the 'warning' or 'over temperature' temperature states. The Operating Condition Change bit Shall be set when the Source operating in the Programmable Power Supply mode detects it has changed its operating condition between Constant Voltage (CV) and Current Limit (CL). 6.4.6.1.5 Source Input Change Event The Source Input Change Event bit Shall be set when the Source/Sink's input changes. For example, when the AC input is removed, and the Source/Sink continues to be powered from one or more of its batteries or when AC returns and the Source/Sink transitions from Battery to AC operation or when the Source/Sink changes operation from one (or more) Battery to another (or more) Battery. B15…4 Reserved Shall be set to zero B3…0 Extended Alert Event Type When the Extended Alert Event bit in the Type of Alert field equals ‘1’, then the Extended Alert Event Type field indicates the event which has occurred:  0 = Reserved.  1 = Power state change (DFP only)  2 = Power button press (UFP only)  3 = Power button release (UFP only)  4 = Controller initiated wake e.g., Wake on LAN (UFP only)  5-15 = Reserved When the Extended Alert Event bit in the Type of Alert field equals ‘0’, then the Extended Alert Event Type field is Reserved and Shall be set to zero. Table 6.47 Alert Data Object (ADO) (Continued) Bit(s) Field Description Page 200 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6.1.6 Over-Voltage Protection Event The OVP Event bit Shall be set when the Sink detects its output voltage exceeds its limits triggering its protection circuitry. The OVP Event bit May be set when the Source detects its output voltage exceeds its limits triggering its protection circuitry. 6.4.6.1.7 Extended Alert Event The Extended Alert Event bit Shall be set when the event is defined as an Extended Alert Type. 6.4.6.2 Fixed Batteries The Fixed Batteries field indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. Once the Alert Message has been sent the Fixed Batteries field Shall be cleared. 6.4.6.3 Hot Swappable Batteries The Hot Swappable Batteries field indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 0 and B19 corresponds to Battery 3. Once the Alert Message has been sent the Hot Swappable Batteries field Shall be cleared. 6.4.6.4 Extended Alert Event Types The Extended Alert Event Type field provides extensions to the available types for the Alert Message. If the Extended Alert Event Type bit is not set, then the Extended Alert Event Type is Reserved and Shall be set to zero. 6.4.6.4.1 Power State Change The Power state change event value May be set when the DFP transitions into a new power state. The new power state Shall be communicated via the Power state change byte in the Status Message. This Message Should be sent by the host in response to any system power state change. 6.4.6.4.2 Power Button Press The Power button press event value May be set when the power button on the UFP is pressed. The press and release events are separated into two different events so that devices that respond differently to a long button press will see a long button press. On the host-side, the power button press event typically initiates the same behavior as a power button press of the host's power button. 6.4.6.4.3 Power Button Release If a Power button press event was sent, then the Power button release event value Shall be sent by the UFP following the Power button press event. If a physical power button press initiated the Power button press event, then the Power button release event Should be sent when the physical button is released. 6.4.6.4.4 Controller Initiated Wake The Controller initiated wake is used to communicate a wake event from the UFP to the DPF such as Wake on LAN from a NIC or another controller. This event doesn't need the press/release form of the Power button press, because it only needs to communicate the presence of the event, and not the timing. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 201 6.4.7 Get_Country_Info Message The Get_Country_Info Message Shall be sent by a Port to get country specific information from its Port Partner using the country's Alpha-2 Country Code defined by [ISO 3166]. The Port Partner responds with a Country_Info Message that contains the country specific information. The Get_Country_Info Message Shall be as shown in Figure 6.30, "Get_Country_Info Message" and Table 6.48, "Country Code Data Object (CCDO)". For example, if the request is for China information, then the Country Code Data Object (CCDO) would be CCDO [31:0] = 434E0000h for "CN" country code. Figure 6.30 Get_Country_Info Message Table 6.48 Country Code Data Object (CCDO) Bit(s) Description B31…24 First character of the Alpha-2 Country Code defined by [ISO 3166] B23…16 Second character of the Alpha-2 Country Code defined by [ISO 3166] B15…0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 CCDO Page 202 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8 Enter_USB Message The Enter_USB Message Shall be sent by the DFP to its UFP Port Partner and to the Cable Plug(s) of an Active Cable, when in an Explicit Contract, to enter a specified USB Mode of operation. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). When entering [USB4] operation, the Enter_USB Message Shall be sent by a [USB4] PDUSB Hub's DFP(s) or [USB4] PDUSB Host's DFP(s) within tEnterUSB:  following a PD Connection.  after a Data Reset to enter [USB4] operation is completed.  after a Data Role Swap is completed. The Enter_USB Message May be sent by a PDUSB Hub's DFP(s) or PDUSB Host's DFP(s) within tEnterUSB following a PD Connection or after a Data Reset to enter [USB 3.2] or [USB 2.0] operation. The Enter_USB Message Shall be used by a PDUSB Hub's DFP(s) to speculatively train the USB links or enter [DPTC2.1] or [TBT3] Alternate Modes prior to the presence of a host. In this case, the Host Present bit Shall be cleared. When the Host is Connected the Enter_USB Message Shall be resent with the Host Present bit set. The Enter_USB Message's Enter USB Data Object (EUDO), received from the Root Hub when the USB Host is connected, Shall be propagated down through the Hub tree. See [USB Type-C 2.4] USB4® Hub Connection Requirements. The Enter_USB Message Shall be as shown in Figure 6.31, "Enter_USB Message" and Table 6.49, "Enter_USB Data Object (EUDO)". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 203 Figure 6.31 Enter_USB Message Table 6.49 Enter_USB Data Object (EUDO) Bit(s) Field Description B31 Reserved Shall be set to zero. B30…28 USB Mode 1  000b:  001b:  010b:  111b…011b: Reserved, Shall Not be used. B27 Reserved Shall be set to zero. B26 USB4 DRD 2  0b: Not capable of operating as a [USB4] Device  1b: Capable of operating as a [USB4] Device B25 USB3 DRD 2  0b: Not capable of operating as a [USB 3.2] Device  1b: Capable of operating as a [USB 3.2] Device B24 Reserved Shall be set to zero. B23…21 Cable Speed 2,3  000b: [USB 2.0]only, no SuperSpeed support  001b: [USB 3.2] Gen1  010b: [USB 3.2]Gen2 and [USB4] Gen2  011b: [USB4] Gen3  100b: [USB4] Gen4  101b…111b: Reserved, Shall Not be used. B20…19 Cable Type 2,3  00b: Passive  01b: Active Re-timer  10b: Active Re-driver  11b: Optically Isolated B18…17 Cable Current 2  00b = VBUS is not supported  01b = Reserved  10b = 3A  11b = 5A B16 PCIe Support 2 [USB4] PCIe tunneling supported by the host B15 DP Support 2 [USB4] DP tunneling supported by the host B14 TBT Support 2 [TBT3] is supported by the host’s USB4® Connection Manager B13 Host Present 2 A Host is present at the top of the USB tree. When this bit is set PCIe Support, DP Support and TBT Support represent the Host’s Capabilities that Shall be propagated down the Hub tree. B12…0 Reserved Shall be set to zero. 1) Entry into [USB 3.2] and [USB4] include entry into [USB 2.0]. 2) Shall be Ignored when received by a Cable Plug (e.g., SOP’ or SOP’’). 3) The DFP Shall interpret the Cable Plug’s reported capability as defined in [USB Type-C 2.4] in the USB4 Discovery and Entry Section. Header No. of Data Objects = 1 EUDO Page 204 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8.1 USB Mode Field The USB Mode field Shall be used by the DFP to direct the USB Mode the Port Partner is to enter. 6.4.8.2 USB4® DRD Field The USB4 DRD field Shall be set when the Host DFP is capable of operating as a [USB4] Device. A [USB4] Host DFP that sets the USB4 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.3 USB3 DRD Field The USB3 DRD field Shall be set when the Host DFP is capable of operating as a [USB 3.2] Device. A [USB 3.2] Host DFP that sets the USB3 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.4 Cable Speed Field The Cable Speed field Shall be used to indicate the cable's maximum speed. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.5 Cable Type Field The Cable Type field Shall be used to indicate whether the cable is passive or active. Further if the cable is active, it indicates the type of active circuits in the cable and if the cable is optically isolated. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.6 Cable Current Field The Cable Current field Shall be used to indicate the cable's current carrying capability. The value is reported by the Cable Plug in the VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field. 6.4.8.7 PCIe Support Field The PCIe Support field Shall be set when the Host DFP is capable of tunneling PCIe over [USB4]. The PCIe Support field May be set speculatively when the Hub's DFP is capable of tunneling PCIe over [USB4]. 6.4.8.8 DP Support Field The DP Support field Shall be set when the Host DFP is capable of tunneling DP over [USB4]. The DP Support field May be set speculatively when the Hub's DFP is capable of tunneling DP over [USB4]. 6.4.8.9 TBT Support Field The TBT Support field Shall be set when the Host DFP is capable of tunneling ThunderboltTM over [USB4] and that the Connection Manager (CM) supports discovery and configuration of Thunderbolt 3 devices connected to the DFP of [USB4] Hubs. The TBT Support field May be set speculatively when the Hub's DFP is capable of tunneling Thunderbolt over [USB4]. 6.4.8.10 Host Present Field The Host Present field Shall be set to indicate that a Host is present upstream. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 205 6.4.9 EPR_Request Message An EPR_Request Message Shall be sent by a Sink, operating in EPR Mode, to request power, typically during the request phase of a power Negotiation. The EPR_Request Message Shall be sent in response to the most recent EPR_Source_Capabilities Message. The EPR_Request Message Shall return a Sink Request Data Object (RDO) that Shall identify the Power Data Object being requested followed by a copy of the Power Data Object being requested. Note: The requested Power Data Object May be either an EPR (A)PDO or SPR (A)PDO. The EPR_Request Message Shall be as shown in Figure 6.32, "EPR_Request Message". Figure 6.32 EPR_Request Message The Source Shall verify the PDO in the EPR_Request Message exactly matches the PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO. The Source Shall respond to an EPR_Request Message in the same manner as it responds to a Request Message with an Accept Message, or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Explicit Contract Negotiation process for EPR is the same as the process for SPR Mode except that the Source_Capabilities Message is replaced by the EPR_Source_Capabilities and the Request Message is replaced by the EPR_Request Message. An EPR Source operating in SPR Mode that receives a EPR_Request Message Shall initiate a Hard Reset. The RDO takes a different form depending on the kind of power requested. The PDO and APDO formats are detailed in Section 6.4.2, "Request Message". Header No. of Data Objects = 2 RDO Copy of PDO Page 206 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.10 EPR_Mode Message The EPR_Mode Message is used to enter, acknowledge, and exit the EPR Mode. The Action field is used to describe the action that is to be taken by the recipient of the EPR_Mode Message. The Data field provides additional information for the Message recipient in the EPR Mode Data Object (ERMDO). The EPR_Mode Message Shall be as shown in Figure 6.33, "EPR Mode DO Message" and Table 6.50, "EPR Mode Data Object (EPRMDO)". Figure 6.33 EPR Mode DO Message 6.4.10.1 Process to enter EPR Mode An EPR Source Shall enter EPR Mode upon request by an EPR Sink connected with an EPR Cable when able to offer the Source Capabilities as defined in the Power Rules (See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable"). For Port Partners to successfully enter EPR Mode, the following conditions must be met:  The Sink Shall request entry into the EPR Mode. Table 6.50 EPR Mode Data Object (EPRMDO) Bit(s) Field Description B31…24 Action Value Action Sent By 0x00 Reserved and Shall Not be used. 0x01 Enter Sink only 0x02 Enter Acknowledged Source only 0x03 Enter Succeeded Source only 0x04 Enter Failed Source only 0x05 Exit Sink or Source 0x06…0xFF Reserved and Shall Not be used. B23...16 Data Action Field Data Field Value Enter Shall be set to the EPR Sink Operational PDP Enter Acknowledged Shall be set to zero Enter Succeeded Shall be set to zero Enter Failed Shall be one of the following values:  0x00 - Unknown cause  0x01 - Cable not EPR Capable  0x02 –Source failed to become VCONN Source.  0x03 – EPR Capable bit not set in RDO.  0x04 – Source unable to enter EPR Mode1.  0x05 - EPR Capable bit not set in PDO. All other values are Reserved and Shall Not be used Exit Shall be set to zero B15...0 Reserved Shall be set to zero 1) The Sink May retry entering EPR Mode after receiving this Enter Failed response. Header No. of Data Objects = 1 EPRMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 207  The Source Shall verify the cable is EPR Capable.  A Sink Shall Not be Connected to the Source through a Charge Through VPD (CT-VPD).  The Source and Sink Shall already be in an SPR Explicit Contract.  The EPR Capable bit Shall be set in the Fixed Supply 5V PDO.  The EPR Capable bit Shall have been set in the RDO in the last Request Message received by the Source. To verify the cable is EPR Capable, the EPR Source Shall have already done the following (see Section 6.6.21.4, "tEPRSourceCableDiscovery"):  Discover the cable prior to entering its First Explicit Contract  Alternatively, within tEPRSourceCableDiscovery of entry into the First Explicit Contract  If it is the VCONN Source, discover the cable.  If not the VCONN Source, do a VCONN Swap then discover the cable. and can verify the cable is EPR Capable by completing steps 5 and 6 in the entry process in Figure 6.34, "Illustration of process to enter EPR Mode". The EPR Mode entry process is a Non-interruptible multi-Message AMS. An illustration of this AMS is shown in Figure 6.34, "Illustration of process to enter EPR Mode". Note: Figure 6.34, "Illustration of process to enter EPR Mode" is not Normative but is Informative only. Page 208 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.34 Illustration of process to enter EPR Mode The entry process Shall follow these steps in order: 1) The Sink Shall send the EPR_Mode Message with the Action field set to 1 (Enter) and the Data field set to its Operational PDP. If the EPR Source receives an EPR_Mode Message with the Action field not set to Enter it Shall initiate a Soft Reset. 2) The Source Shall do the following: EPR_Mode Enter #1 Start SPR Mode EPR Mode Sink Source Cable EPR Entry process SPR contract in place #2.a Sink EPR Capable? Abort EPR Entry Send Entry Failed – Sink not EPR Capable #2.b Source EPR Capable? Abort EPR Entry Send Entry Failed – Source not EPR Capable #2.c Source EPR Capable Now? Abort EPR Entry Send Entry Failed – Source unable to enter EPR #2.d Send EPR Ack #3 Received EPR Ack? #4 Known Cable? #7 Send Enter Succeeded N N N N N #5 Is VCONN Source? #8 Received Enter successful? N Error Send Soft Reset #6.a-d EPR Cable? Abort EPR Entry Send Entry Failed – Source not VCONN Source N Y Y Y Y EPR_MODE Enter Succeeded Y Y Y #5 Is VCONN Source? N #5 VCONN Swap N Abort EPR Entry Send Entry Failed – Not EPR Cable Y Y #4 EPR Capable? Y N Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 209 a) Verify the EPR Capable bit was set in the most recent RDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 3 ("EPR Mode Capable bit not set in the RDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. b) Verify the EPR Capable bit was set in the most recent 5V Fixed Supply PDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 5 ("EPR Mode Capable bit not set in the Fixed Supply 5V PDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. c) Verify the Source is still able to support EPR Mode. If not, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and Data field set to 4 ("Unable at this time"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. The Sink May at some time in the future send another request to enter EPR Mode. d) Send an EPR_Mode Message with the Action field set to 2 (Enter Acknowledged). 3) If the Sink receives any Message, other than an EPR_Mode Message with the Action Field set to 2, the Sink Shall initiate a Soft Reset. 4) When the EPR Source has used the Discover Identity Command to determine and remembers the Cable Capabilities or the EPR Source is connected with a captive cable: a) If the cable is EPR Capable it Should go directly to Step 7, but May continue to Step 5. b) If the cable is not EPR Capable it Shall do the following: c) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 1 ("Cable not EPR capable"). d) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 5) If the Source is not the VCONN Source, it Shall send a VCONN_Swap Message a) If the Source fails to become the VCONN Source, it Shall: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 2 (not VCONN Source). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 6) The Source Shall use the Discover Identity Command to read the cable's e-Marker and verify the following: a) Cable VDO - Maximum VBUS Voltage (Passive Cable)/Maximum VBUS Voltage (Active Cable) field is 11b (50V) b) Cable VDO - VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field is 10b (5A) c) Cable VDO - EPR Capable (Passive Cable)/EPR Capable (Active Cable) field is 1b (EPR Capable) d) If the cable fails to respond to the Discover Identity Command or is not EPR Capable, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field to1 ("Cable not EPR capable"). Page 210 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 7) The Source Shall send the EPR_Mode Message with the Action field set to 3 (Enter Succeeded) and Shall enter EPR Mode. 8) If the Sink receives an EPR_Mode Message with the Action field set to 3 (Enter Succeeded) it Shall enter EPR Mode, otherwise it Shall initiate a Soft Reset. If the EPR Mode entry process successfully completes within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Source Shall send an EPR_Source_Capabilities Message within tFirstSourceCap. If the EPR Mode entry process has not been aborted or does not complete within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Sink Shall initiate a Soft Reset. 6.4.10.2 Operation in EPR Mode While operating in EPR Mode, the Source Shall only send EPR_Source_Capabilities Messages to Advertise its power Capabilities and the Sink Shall only respond with EPR_Request Messages to Negotiate Explicit Contracts. The EPR_Request Message May be for either an SPR or EPR (A)PDO. If the Source sends a Source_Capabilities Message, that is not in response to a Sink Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. If the Sink sends a Request Message, the Source Shall initiate a Hard Reset. The Source Shall monitor the CC communications path to ensure that there is periodic traffic. The Sink Shall send an EPR_KeepAlive Message when it has not sent any Messages for more than tSinkEPRKeepAlive to ensure there is timely periodic traffic. If there is no traffic for more than tSourceEPRKeepAlive, the Source Shall initiate a Hard Reset. 6.4.10.3 Exiting EPR Mode 6.4.10.3.1 Commanded Exit While in EPR Mode, either the Source or Sink May exit EPR Mode by sending an EPR_Mode Message with the Action field set to 5 (Exit). The ports Shall be in an Explicit Contract with an SPR (A)PDO prior to the EPR Mode exit process by either:  The Source sending an EPR_Source_Capabilities Message with no EPR (A)PDO s (e.g., only SPR (A)PDO s) or  The Sink negotiating a new Explicit Contract with bit 31 in the RDO set to zero (e.g., only SPR (A)PDO s)). The process to exit EPR Mode is a Non-interruptible multi-Message AMS and Shall follow these steps in order: 1) The Port Partners Shall be in an Explicit Contract with an SPR (A)PDO. 2) Either the Source or Sink Shall send an EPR_Mode Message with the Action field set to 5 (Exit) to exit the EPR Mode 3) The Source Shall send a Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit). 4) If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap of the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit), Sink Shall initiate a Hard Reset. 6.4.10.3.2 Implicit Exit EPR Mode Shall be exited as the side-effect of the Power Role Swap and Fast Role Swap processes. This is because at the end of these processes VBUS will be at vSafe5V and the Ports will be in an Implicit Contract. The New Source will then send a Source_Capabilities Message (not an EPR_Source_Capabilities Message) to begin the process of Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 211 negotiating an SPR Explicit Contract. Once an SPR Explicit Contract is entered, the Source and Sink can then enter EPR Mode if needed. 6.4.10.3.3 Exits due to errors Other critical errors can occur while in EPR Mode; these errors Shall result in Hard Reset being initiated by the Port that detects the error. Some of these errors include:  An EPR_Mode Message with the Action field set to 5 (Exit) to exit EPR Mode is received by a Port in an Explicit Contract with an EPR (A)PDO.  The Sink receives an EPR_Source_Capabilities Message with an EPR (A)PDO in any of the first seven object positions.  The (A)PDO in the EPR_Request Message does not match the (A)PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO.  The Source receives a Request Message.  The Sink receives a Source_Capabilities Message not in response to a Get_Source_Cap Message. Page 212 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.11 Source_Info Message The Source_Info Message Shall be sent in response to a Get_Source_Info Message. The Source_Info Message contains one Source Information Data Object (SIDO). The Source_Info Message returns a SIDO whose format Shall be as shown in Figure 6.35, "Source_Info Message" and Table 6.51, "Source_Info Data Object (SIDO)". The Number of Data Objects field in the Source_Info Message Shall be set to 1. The Port Maximum PDP, Port Present PDP, Port Reported PDP and the Port Type are used to identify Capabilities of a Source Port. Figure 6.35 Source_Info Message 6.4.11.1 Port Type Field Port Type is a Static field that Shall be used to indicate whether the amount of power the Port can provide is fixed or can change dynamically. For Ports that are part of a Shared Capacity Group, the Port Type field Shall be set to Managed Capability Port. For Ports not part of a Shared Capacity Group, the Port Type field May be set to either Managed Capability Port or Guaranteed Capability Port. 6.4.11.2 Port Maximum PDP Field Port Maximum PDP is a Static field that Shall report the integer portion of the PDP Rating of the Port. A Guaranteed Capability Port (as indicated by the Port Type field being set to '1') Shall always be capable of supplying this amount of power. A Managed Capability Port (as indicated by the Port Type field being set to '0') Shall be able to offer this amount of power at some time. The Port Maximum PDP Shall be the same as the larger of the SPR Source PDP Rating and the EPR Source PDP Rating in the Source_Capabilities_Extended Message. 6.4.11.3 Port Present PDP Field The Port Present PDP field Shall indicate the integer part of the amount of power the Port is presently capable of supplying including limitations due to Cable Capabilities or abnormal operating conditions (e.g., elevated temperature, low input voltage, etc.). A Guaranteed Capability Port Shall always set its Port Present PDP to be the same as its Port Maximum PDP or the highest possible value when limited. Table 6.51 Source_Info Data Object (SIDO) Bit(s) Field Description B31 Port Type  0 = Managed Capability Port  1 = Guaranteed Capability Port B30…24 Reserved Shall be set to zero B23...16 Port Maximum PDP Power the Port is designed to supply B15…8 Port Present PDP Power the Port is presently capable of supplying B7…0 Port Reported PDP Power the Port is actually advertising Header No. of Data Objects = 1 SIDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 213 A Managed Capability Port that is part of a Shared Capacity Group Shall set its Port Present PDP to Shared Port Power Available as defined in [USB Type-C 2.4] or to a lower value when limited. A Managed Capability Port that is part of an Assured Capacity Group Shall set its Port Present PDP to the Port Maximum PDP or the highest value possible when limited. 6.4.11.4 Port Reported PDP Field The Port Reported PDP field Shall track the amount of power the Port is offering in its Source_Capabilities Message or EPR_Source_Capabilities Message. The Port Reported PDP field May be dynamic or Static depending on the Port's other characteristics such as Managed/Guaranteed Capability, SPR/EPR Mode, its power policy etc. Note: The Port Reported PDP field is computed as the integer part of, the largest of the products of the voltage times current of the Fixed Supply PDOs returned in the Source_Capabilities Message or EPR_Source_Capabilities Messages. Page 214 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.12 Revision Message The Revision Message Shall be sent in response to the Get_Revision Message sent by the Port Partner. This Message is used to identify the highest Revision the Port is capable of operating at. The Revision Message contains one Revision Message Data Object (RMDO). The Revision Message returns an RMDO whose format Shall be as shown in Figure 6.36, "Revision Message Data Object"and Table 6.52, "Revision Message Data Object (RMDO)". The Number of Data Objects field in the Revision Message Shall be set to 1. Figure 6.36 Revision Message Data Object E.g., for Revision 3.2, Version 1.1 the fields would be the following:  Revision.major = 0011b  Revision.minor = 0010b  Version.major = 0001b  Version.minor = 0001b Table 6.52 Revision Message Data Object (RMDO) Bit(s) Description B31…28 Revision.major B27…24 Revision.minor B23...20 Version.major B19...16 Version.minor B15...0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 RMDO
6.5 - Extended Message...................................................................................................................... (Page 215)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 215 6.5 Extended Message An Extended Message Shall contain an Extended Message Header (indicated by the Extended field in the Message Header being set) and be followed by zero or more data bytes. Additional bytes that might be added to existing Messages in future Revision of this specification Shall be Ignored. The format of the Extended Message is defined by the Message Header's Message Type field and is summarized in Table 6.53, "Extended Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.53 Extended Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0 0000 Reserved All values not explicitly defined are Reserved and Shall Not be used. 0 0001 Source_Capabilities_Extended Source or Dual-Role Power See Section 6.5.1 SOP only 0 0010 Status Source, Sink or Cable Plug See Section 6.5.2 SOP* 0 0011 Get_Battery_Cap Source or Sink See Section 6.5.3 SOP only 0 0100 Get_Battery_Status Source or Sink See Section 6.5.4 0 0101 Battery_Capabilities Source or Sink See Section 6.5.5 SOP only 0 0110 Get_Manufacturer_Info Source or Sink See Section 6.5.6 SOP* 0 0111 Manufacturer_Info Source, Sink or Cable Plug See Section 6.5.7 SOP* 0 1000 Security_Request Source or Sink See Section 6.5.8.1 SOP* 0 1001 Security_Response Source, Sink or Cable Plug See Section 6.5.8.2 SOP* 0 1010 Firmware_Update_Request Source or Sink See Section 6.5.9.1 SOP* 0 1011 Firmware_Update_Response Source, Sink or Cable Plug See Section 6.5.9.2 SOP* 0 1100 PPS_Status Source See Section 6.5.10 SOP only 0 1101 Country_Info Source or Sink See Section 6.5.12 SOP only 0 1110 Country_Codes Source or Sink See Section 6.5.11 SOP only 0 1111 Sink_Capabilities_Extended Sink or Dual-Role Power See Section 6.5.13 SOP only 1 0000 Extended_Control Source or Sink See Section 6.5.14 SOP only 1 0001 EPR_Source_Capabilities Source or Dual-Role Power See Section 6.5.15.2 SOP only 1 0010 EPR_Sink_Capabilities Sink or Dual-Role Power See Section 6.5.15.3 SOP only 1 0011... 1 1101 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 1110 Vendor_Defined_Extended Source, Sink or Cable Plug See Section 6.5.16 SOP* 1 1111 Reserved All values not explicitly defined are Reserved and Shall Not be used. Page 216 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1 Source_Capabilities_Extended Message The Source_Capabilities_Extended Message Should be sent in response to a Get_Source_Cap_Extended Message. The Source_Capabilities_Extended Message enables a Source or a DRP to inform the Sink about its Capabilities as a Source. The Source_Capabilities_Extended Message Shall return a 25-byte Source Capabilities Extended Data Block (SCEDB) whose format Shall be as shown in Figure 6.37, "Source_Capabilities_Extended Message" andTable 6.54, "Source Capabilities Extended Data Block (SCEDB)". Figure 6.37 Source_Capabilities_Extended Message Table 6.54 Source Capabilities Extended Data Block (SCEDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 XID Value provided by the USB-IF assigned to the product 8 FW Version Firmware version number 9 HW Version Hardware version number 10 Voltage Regulation Bit Description 1…0  00b: 150mA/µs Load Step (default)  01b: 500mA/µs Load Step  11b…10b: Reserved and Shall Not be used. 2  0b: 25% IoC (default)  1b: 90% IoC 3…7 Reserved and Shall Not be used 11 Holdup Time Output will stay with regulated limits for this number of milliseconds after removal of the AC from the input.  0x00 = feature not supported Note: A value of at least 3ms Should be used (see Section 7.1.12.2, "Holdup Time Field"). 12 Compliance Compliance in SPR Mode: Bit Description 0 LPS compliant when set 1 PS1 compliant when set 2 PS2 compliant when set 3…7 Reserved and Shall Not be used 13 Touch Current Bit Description 0 Low touch current EPS when set 1 Ground pin supported when set 2 Ground pin intended for protective earth when set 3...7 Reserved and Shall Not be used Extended Header Data Size = 25 SCEDB (25-byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 217 6.5.1.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Source's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 14 Peak Current1 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 16 Peak Current2 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 18 Peak Current3 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 20 Touch Temp Temperature conforms to:  0 = [IEC 60950-1] (default)  1 = [IEC 62368-1] TS1  2 = [IEC 62368-1] TS2 Note: All other values Reserved and Shall Not be used. 21 Source Inputs Bit Description 0  0b: No external supply  1b: External supply present 1 If bit 0 is set:  0b: External supply is constrained.  1b: External supply is unconstrained. If bit 0 is not set Reserved and Shall be set to zero 2  0b: No internal Battery  1b: Internal Battery present 3...7 Reserved and Shall be set to zero 22 Number of Batteries/ Battery Slots Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 23 SPR Source PDP Rating 0…6: Source PDP Rating (EPR Source’s PDP Rating when operating in SPR Mode. 7: Reserved and Shall be set to zero 24 EPR Source PDP Rating 0…7: EPR Source PDP Rating Table 6.54 Source Capabilities Extended Data Block (SCEDB) (Continued) Offset Field Description Page 218 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Source's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.1.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.1.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.1.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.1.6 Voltage Regulation Field The Voltage Regulation field contains bits covering Load Step Slew Rate and Magnitude. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.1.6.1 Load Step Slew Rate The Source Shall report its load step response capability in bits 0…1 of the Voltage Regulation bit field. 6.5.1.6.2 Load Step Magnitude The Source Shall report its load step magnitude rate as a percentage of IoC in bit 2 of the Voltage Regulation field. 6.5.1.7 Holdup Time Field The Holdup Time field Shall contain the Source's holdup time (see Section 7.1.12.2, "Holdup Time Field"). 6.5.1.8 Compliance Field The Compliance is Static and Shall contain the standards the Source is compliant with in SPR (see Section 7.1.12.3, "Compliance Field"). 6.5.1.9 Touch Current Field The Touch Current field reports whether the Source meets certain leakage current levels and if it has a ground pin. A Source Shall set the Touch Current bit (bit 0) when their leakage current is less than 65µA rms when Source's maximum capability is less than or equal to 30W, or when their leakage current is less than 100 µA rms when its power capability is between 30W and 100W. The total combined leakage current Shall be measured in accordance with [IEC 60950-1] when tested at 250VAC rms at 50 Hz. A Source with a ground pin Shall set the Ground pin bit (bit 1). A Source whose Ground pin is intended to be connected to a protective earth Shall set both bit1 and bit 2. 6.5.1.10 Peak Current Field The Peak Current1/Peak Current2/Peak Current3 fields Shall contain the combinations of Peak Current that the Source supports (see Section 7.1.12.4, "Peak Current"). Peak Current provides a means for Source report its ability to provide current in excess of the Negotiated amount for short periods. The Peak Current descriptor defines up to three combinations of% overload, duration and duty Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 219 cycle defined as Peak Current1, Peak Current2 and Peak Current3 that the Source supports. A Source May offer no Peak Current capability. A Source Shall populate unused Peak Current bit fields with zero. The Bit Fields within Peak Current1, Peak Current2 and Peak Current3 contain the following subfields:  Percentage Overload  Shall be the maximum peak current reported in 10% increments as a percentage of the Negotiated operating current (IoC) offered by the Source. Values higher than 25 (11001b) are clipped to 250%.  Overload Period  Shall be the minimum rolling average time window in 20ms increments, where a value of 20ms is recommended.  Duty Cycle  Shall be the maximum percentage of overload period reported in 5% increments. The values Should be 5%, 10% and 50% for PeakCurrent1, PeakCurrent2, and PeakCurrent3, respectively.  VBUS Droop  Shall be set to one to indicate there is an additional 5% voltage droop on VBUS when the overload conditions occur as defined by vSrcPeak. However, it is recommended that the Source Should pro- vide VBUS in the range of vSrcNew when overload conditions occur and set this bit to zero. 6.5.1.11 Touch Temp Field The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Source's enclosure. Safety limits for the Source's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Source May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.1.12 Source Inputs Field The Source Inputs field Shall identify the possible inputs that provide power to the Source:  When bit 0 is set, the Source can be sourced by an external power supply.  When bits 0 and 1 are set, the Source can be sourced by an external power supply which is assumed to be effectively "infinite" i.e., it won't run down over time.  When bit 2 is set the Source can be sourced by an internal Battery. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. Note: Bit 2 May be set independently of bits 0 and 1. 6.5.1.13 Number of Batteries/Battery Slots Field The Number of Batteries/Battery Slots field Shall report the number of Fixed Batteries and Hot Swappable Battery Slots the Source supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. A Source Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 220 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.14 SPR Source PDP Rating Field For an SPR Source the SPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an EPR Source, the SPR Source PDP Rating field Shall report the integer portion of the maximum amount of power that the Port is designed to deliver in SPR Mode. The SPR Source PDP Rating field that is reported Shall be Static. 6.5.1.15 EPR Source PDP Rating Field For an EPR Source the EPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an SPR Source this field Shall be set to zero. The EPR Source PDP Rating field that is reported Shall be Static. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 221 6.5.2 Status Message The Status Message Shall be sent in response to a Get_Status Message. The content of the Status Message depends on the target of the Get_Status Message. When sent to SOP the Status Message returns the status of the Port's Port Partner. When sent to SOP’ or SOP’’ the Status Message returns the status of one of the Active Cable's Cable Plugs. 6.5.2.1 SOP Status Message A Status Message, sent in response to Get_Status Message to SOP, enables a Port to inform its Port Partner about the present status of the Source or Sink. Typically, a Get_Status Message will be sent by the Port after receipt of an Alert Message. Some of the reported events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Status Message returns a 7-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.38, "SOP Status Message" and Table 6.55, "SOP Status Data Block (SDB)". Figure 6.38 SOP Status Message Table 6.55 SOP Status Data Block (SDB) Offset (Byte) Field Description 0 Internal Temp Source or Sink’s internal temperature in °C  0 = feature not supported  1 = temperature is less than 2°C.  2-255 = temperature in °C. 1 Present Input Bit Description 0 Reserved and Shall be set to zero 1 External Power when set 2 External Power AC/DC (Valid when Bit 1 set)  0: DC  1: AC Reserved when Bit 1 is zero 3 Internal Power from Battery when set 4 Internal Power from non-Battery power source when set 5...7 Reserved and Shall be set to zero 2 Present Battery Input When Present Input field bit 3 set Shall contain the bit corresponding to the Battery or Batteries providing power:  Upper nibble = Hot Swappable Battery (b7…4)  Lower nibble = Fixed Battery (b3…0) When Present Input field bit 3 is not set this field is Reserved and Shall be set to zero. Extended Header Data Size = 7 SDB (7-byte block) Page 222 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 3 Event Flags Bit Flag Description 0 Reserved and Shall be set to zero 1 OCP Event OCP event when set 2 OTP Event OTP event when set 3 OVP Event OVP event when set 4 CL/CV Mode In PPS Mode only: CL mode when set, CV mode when cleared 5...7 Reserved and Shall be set to zero 4 Temperature Status Bit Description 0 Reserved and Shall be set to zero 1...2  00 – Not Supported.  01 – Normal  10 – Warning  11 – Over temperature 3...7 Reserved and Shall be set to zero 5 Power Status Bit Description 0 Reserved and Shall be set to zero 1 Source power limited due to cable supported current 2 Source power limited due to insufficient power available while sourcing other ports 3 Source power limited due to insufficient external power 4 Source power limited due to Event Flags in place (Event Flags must also be set) 5 Source power limited due to temperature 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 223 6.5.2.1.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of a portion of the Source or Sink. 6.5.2.1.2 Present Input Field The Present Input field indicates which supplies are presently powering the Source or Sink. The following bits are defined:  Bit 1: indicates that an external power source is present.  Bit 2: indicates whether the external unconstrained power source is AC or DC.  Bit 3: indicates that power is being provided from Battery.  Bit4: indicates an alternative internal source of power that is not a Battery. 6.5.2.1.3 Present Battery Input Field The Present Battery Input field indicates which Battery or Batteries are presently supplying power to the Source or Sink. The Present Battery Input field is only Valid when the Present Input field indicates that there is Internal Power from Battery. The upper nibble of the field indicates which Hot Swappable Battery/Batteries are supplying power with bit 4 in upper nibble corresponding to Battery 4 and bit 7 in the upper nibble corresponding to Battery 7 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). The lower nibble of the field indicates which Fixed Battery/Batteries are supplying power with bit 0 in lower nibble corresponding to Battery 0 and bit 3 in the lower nibble corresponding to Battery 3 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). 6 Power State Change Bit Description 0...2 New Power State Value Description 0 Status not supported 1 S0 2 Modern Standby 3 S3 4 S4 5 S5 (Off with battery, wake events supported) 6 G3 (Off with no battery, wake events not supported) 7 Reserved and Shall be set to zero 3...5 New Power State indicator Value Description 0 Off LED 1 On LED 2 Blinking LED 3 Breathing LED 4...7 Reserved and Shall be set to zero 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Page 224 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.1.4 Event Flags Field The Event Flags field returns event flags. The OTP, OVP and OCP event flags Shall be set when there is an event and Shall only be cleared when read with the Get_Status Message. When the OTP Event flag is set the Temperature Status field Shall also be set to over temperature. The CL/CV Mode flag is only Valid when operating as a Programmable Power Supply and Shall be Ignored otherwise. When the Source is operating as a Programmable Power Supply the CL/CV Mode flag Shall be set when operating in Current Limit mode (CL) and Shall be cleared when operating in Constant Voltage mode (CV). 6.5.2.1.5 Temperature Status Field The Temperature Status field returns the current temperature status of the device either: normal, warning or over temperature. When the Temperature Status field is set to over temperature the OTP Event flag Shall also be set. 6.5.2.1.6 Power Status Field The Power Status field indicates the current status of a Source. A non-zero return of the field indicates Advertised Source power is being reduced for either:  The cable does not support the full Source current.  The Source is supplying power to other ports and is unable to provide its full power.  The external power to the Source is insufficient to support full power.  An Event has occurred that is causing the Source to reduce its Advertised power. A Sink Shall set this field to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 225 6.5.2.1.7 Power state change The Power State Change field contains two status bytes; the New Power State and New Power State indicator status bytes. 6.5.2.1.7.1 New power state The New Power State status byte indicates a power state change to one of the specified power states. Any device that supports the ACPI standard system power states Shall use the ACPI states. For devices that do not support the ACPI power states, the following mapping Should be used:  High power (on) state -> S0  Sleep state -> S3  Low power (off) state -> S5 or G3 6.5.2.1.7.2 New power state indicator The New Power State indicator status byte defines the host's desired indicator for the specified power state. This indicator allows several possibilities for predefined behaviors that the host can specify to indicate its system power state to the user via the downstream device. The New Power State indicator is a "best effort" indicator. If the device cannot provide the requested indicator, then it provides the best indicator that it can. If a Breathing indicator cannot be provided, then a Blinking indicator Should be provided. If a Blinking indicator cannot be provided, then a constant on indicator Should be provided. New Power State indicators in decreasing precedence:  Breathing  Blinking  Constant on  No indicator Page 226 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.2 SOP'/SOP'' Status Message A Status Message, sent in response to a Get_Status Message to SOP’ or SOP’’, enables a Source or Sink to get the present status of the Cable's Cable Plug(s). Typically, a Get_Status Message will be used by the USB Host and/or USB Device to manage the Cable's Cable Plug(s) temperature. The Status Message returns a 2-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.39, "SOP'/SOP'' Status Message" and Table 6.56, "“SOP’/SOP’’ Status Data Block (SPDB)”". Passive Cable Plugs Shall Not indicate Thermal Shutdown. Figure 6.39 SOP'/SOP'' Status Message 6.5.2.2.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of the plug in °C. The internal temperature Shall be monotonic. The Cable Plug Shall report its internal temperature every tACTempUpdate. 6.5.2.2.2 Thermal Shutdown Field The Flags flag Shall also be set when the plug's internal temperature exceeds the Internal Maximum Temperature reported in the Active Cable VDO. Once this bit has been set, it Shall remain set and the plug Shall remain in Thermal Shutdown until there is a Hard Reset or the Active Cable's power is removed. The Thermal Shutdown flag Shall Not be cleared by a Cable Reset. Table 6.56 “SOP’/SOP’’ Status Data Block (SPDB)” Offset (Byte) Field Value Description 0 Internal Temp Unsigned Int Cable Plug’s internal temperature in °C.  0 = feature not supported  1 = temperature is less than 2°C.  2…255 = temperature in °C. 1 Flags Bit Field Bit Description 0 Thermal Shutdown 1...7 Reserved and Shall be set to zero Extended Header Data Size = 2 SPDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 227 6.5.3 Get_Battery_Cap Message The Get_Battery_Cap (Get Battery Capabilities) Message is used to request the capability of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Capabilities Message (see Section 6.5.5, "Battery_Capabilities Message") containing a Battery Capabilities Data Block (BCDB) for the targeted Battery. The Get_Battery_Cap Message contains a 1-byte Get Battery Cap Data Block (GBCDB), whose format Shall be as shown in Figure 6.40, "Get_Battery_Cap Message" and Table 6.57, "Get Battery Cap Data Block (GBCDB)". This block defines for which Battery the request is being made. The Data Size field in the Get_Battery_Cap Message Shall be set to 1. Figure 6.40 Get_Battery_Cap Message 6.5.4 Get_Battery_Status Message The Get_Battery_Status (Get Battery Status) Message is used to request the status of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Status Message (see Section 6.4.5, "Battery_Status Message") containing a Battery Status Data Object (BSDO) for the targeted Battery. The Get_Battery_Status Message contains a 1-byte Get Battery Status Data Block (GBSDB) whose format Shall be as shown in Figure 6.41, "Get_Battery_Status Message" and Table 6.58, "Get Battery Status Data Block (GBSDB)". This block contains details of the requested Battery. The Data Size field in the Get_Battery_Status Message Shall be set to 1. Figure 6.41 Get_Battery_Status Message Table 6.57 Get Battery Cap Data Block (GBCDB) Offset Field Description 0 Battery Cap Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Table 6.58 Get Battery Status Data Block (GBSDB) Offset Field Description 0 Battery Status Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Extended Header Data Size = 1 GBCDB Extended Header Data Size = 1 GBSDB Page 228 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.5 Battery_Capabilities Message The Battery_Capabilities Message is sent in response to a Get_Battery_Cap Message. The Battery_Capabilities Message contains one Battery Capability Data Block (BCDB) for one of the Batteries its supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BCDB Shall correspond to the Battery requested in the Battery Cap Ref field contained in the Get_Battery_Cap Message. The Battery_Capabilities Message returns a 9-byte BCDB whose format Shall be as shown in Figure 6.42, "Battery_Capabilities Message" and Table 6.59, "Battery Capability Data Block (BCDB)”". Figure 6.42 Battery_Capabilities Message 6.5.5.1 Vendor ID (VID) The VID field Shall contain the manufacturer VID associated with the Battery, as assigned by the USB-IF, or 0xFFFF in the case that no such VID exists. If the Battery Cap Ref field in the Get_Battery_Cap Message is Invalid, the VID field Shall be 0xFFFF. 6.5.5.2 Product ID (PID) The following rules apply to the PID field. When the VID: Table 6.59 Battery Capability Data Block (BCDB)” Offset (Byte) Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Battery Design Capacity Battery’s design capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = design capacity unknown 6 Battery Last Full Charge Capacity Battery’s last full charge capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = last full charge capacity unknown 8 Battery Type Bit Field Description 0 Invalid Battery Reference Invalid Battery reference when set. 1...7 --- Reserved Extended Header Data Size = 9 BCDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 229  Belongs to the Battery vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  Belongs to the Device vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor.  Is 0xFFFF the PID field Shall be set to 0x0000. 6.5.5.3 Battery Design Capacity Field The Battery Design Capacity field Shall return the Battery's design capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Design Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Design Capacity field Shall be set to 0xFFFF. 6.5.5.4 Battery Last Full Charge Capacity Field The Battery Last Full Charge Capacity field Shall contain the Battery's last full charge capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Last Full Charge Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Last Full Charge Capacity field Shall be set to 0xFFFF. 6.5.5.5 Battery Type Field The Battery Type field is used to report additional information about the Battery's Capabilities. 6.5.5.5.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Cap Message contains a reference to a Battery that does not exist. Page 230 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.6 Get_Manufacturer_Info Message The Get_Manufacturer_Info (Get Manufacturer Info) Message is sent by a Port to request manufacturer specific information relating to its Port Partner, Cable Plug or of a Battery behind a Port. The Port Shall respond by returning a Manufacturer_Info Message (Section 6.5.7, "Manufacturer_Info Message") containing a Manufacturer Info Data Block (MIDB). Support for this feature by the Cable Plug is Optional Normative. The Get_Manufacturer_Info Message contains a 2-byte Get Manufacturer Info Data Block (GMIDB). This block defines whether it is the Device or Battery manufacturer information being requested and for which Battery the request is being made. The Get_Manufacturer_Info Message returns a GMIDB whose format Shall be as shown in Figure 6.43, "Get_Manufacturer_Info Message" and Table 6.60, "Get Manufacturer Info Data Block (GMIDB)". Figure 6.43 Get_Manufacturer_Info Message Table 6.60 Get Manufacturer Info Data Block (GMIDB) Offset Field Description 0 Manufacturer Info Target  0: Port/Cable Plug  1: Battery  255…2: Reserved and Shall Not be used. 1 Manufacturer Info Ref If the Manufacturer Info Target field is Battery (01b) the Manufacturer Info Ref field Shall contain the Battery number reference which is the number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries. Otherwise, this field is Reserved and Shall be set to zero. Extended Header Data Size = 2 GMIDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 231 6.5.7 Manufacturer_Info Message The Manufacturer_Info Message Shall be sent in response to a Get_Manufacturer_Info Message. The Manufacturer_Info Message contains the USB VID and the Vendor's PID to identify the device or Battery and the device or Battery's manufacturer byte array in a variable length Data Block of up to MaxExtendedMsgLegacyLen. The Manufacturer_Info Message returns a Manufacturer Info Data Block (MIDB) whose format Shall be as shown in Figure 6.44, "Manufacturer_Info Message" and Table 6.61, "Manufacturer Info Data Block (MIDB)". Figure 6.44 Manufacturer_Info Message 6.5.7.1 Vendor ID (VID) If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the VID field Shall contain:  The manufacturer's VID associated with the Port/Cable Plug, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Device that has a USB data interface, the Device Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery, the VID field Shall contain:  The manufacturer VID associated with the Battery specified, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message:  Is Invalid, this VID field Shall be 0xFFFF.  Is Battery (01b) and the Manufacturer Info Ref field is Invalid, the VID field Shall be 0xFFFF. 6.5.7.2 Product ID (PID) If the VID is 0xFFFF, the PID field Shall contain 0x0000. Otherwise: Table 6.61 Manufacturer Info Data Block (MIDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Manufacturer String Vendor defined null terminated string of 0…21 characters. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string “Not Supported”. Extended Header Data Size = 5..26 MIDB Page 232 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the PID field Shall contain the device's 16-bit product identifier designated by the device vendor.  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery:  And the VID belongs to the Battery vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  And the VID belongs to the Device vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor. 6.5.7.3 Manufacturer String The Manufacturer String field Shall contain the device’s or Battery's manufacturer string as defined by the vendor. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string "Not Supported". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 233 6.5.8 Security Messages The authentication process between Port Partners or a Port and Cable Plug is fully described in [USBTypeCAuthentication 1.0]. This specification describes two Extended Messages used by the authentication process when applied to PD. In the authentication process described in [USBTypeCAuthentication 1.0] there are three basic exchanges that serve to:  Get the Port or Cable Plug's certificates.  Get the Port or Cable Plug's digest.  Challenge the Port Partner or Cable Plug. Certificates are used to convey information, attested to by a signer, which attests to the Port Partner's or Cable Plug's authenticity. The Port's or Cable Plug's certificates are needed when a Port encounters a Port Partner or Cable Plug it has not been Attached to before. To minimize calculations after the initial Attachment, a Port can also use a digest consisting of hashes of the certificates rather than the certificates themselves. Once the Port has the certificates and has calculated the hashes, it stores the hashes and uses the digest in future exchanges. After the Port gets the certificates or digest, it challenges its Port Partner or the Cable Plug to detect replay attacks. For further details refer to [USBTypeCAuthentication 1.0]. 6.5.8.1 Security_Request The Security_Request Message is used by a Port to pass a security data structure to its Port Partner or a Cable Plug. The Security_Request Message contains a Security Request Data Block (SRQDB) whose format Shall be as shown in Figure 6.45, "Security_Request Message". The contents of the SRQDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.45 Security_Request Message 6.5.8.2 Security_Response The Security_Response Message is used by a Port or Cable Plug to pass a security data structure to the Port that sent the Security_Request Message. The Security_Response Message contains a Security Response Data Block (SRPDB) whose format Shall be as shown in Figure 6.46, "Security_Response Message". The contents of the SRPDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.46 Security_Response Message Extended Header Data Size = 4..260 SRQDB Extended Header Data Size = 4..260 SRPDB Page 234 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.9 Firmware Update Messages The firmware update process between Port Partners or a Port and Cable Plug is fully described in [USBPDFirmwareUpdate 1.0]. This specification describes two Extended Messages used by the firmware update process when applied to PD. 6.5.9.1 Firmware_Update_Request The Firmware_Update_Request Message is used by a Port to pass a firmware update data structure to its Port Partner or a Cable Plug. The Firmware_Update_Request Message contains a Firmware Update Request Data Block (FRQDB) whose format Shall be as shown in Figure 6.47, "Firmware_Update_Request Message". The contents of the FRQDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.47 Firmware_Update_Request Message 6.5.9.2 Firmware_Update_Response The Firmware_Update_Response Message is used by a Port or Cable Plug to pass a firmware update data structure to the Port that sent the Firmware_Update_Request Message. The Firmware_Update_Response Message contains a Firmware Update Response Data Block (FRPDB) whose format Shall be as shown in Figure 6.48, "Firmware_Update_Response Message". The contents of the FRPDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.48 Firmware_Update_Response Message Extended Header Data Size = 4..260 FRQDB Extended Header Data Size = 4..260 FRPDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 235 6.5.10 PPS_Status Message The PPS_Status Message Shall be sent in response to a Get_PPS_Status Message. The PPS_Status Message enables a Sink to query the Source to get additional information about its operational state. The Get_PPS_Status Message and the PPS_Status Message Shall only be supported when the Alert Message is also supported. The PPS_Status Message Shall return a 4-byte PPS Status Data Block (PPSSDB) whose format Shall be as shown in Figure 6.49, "PPS_Status Message" and Table 6.62, "PPS Status Data Block (PPSSDB)". Figure 6.49 PPS_Status Message 6.5.10.1 Output Voltage Field The Output Voltage field Shall return the Source's output voltage at the time of the request. The output voltage is measured either at the Source's receptacle or, if the Source has a captive cable, where the voltage is applied to the cable. The measurement accuracy Shall be +/-3% rounded to the nearest 20mV in SPR PPS Mode. If the Source does not support the Output Voltage field, the field Shall be set to 0xFFFF. 6.5.10.2 Output Current Field The Output Current field Shall return the Source's output current at the time of the request measured at the Source's receptacle. The measurement accuracy Shall be +/-150mA. If the Source does not support the Output Current field, the field Shall be set to 0xFF. Table 6.62 PPS Status Data Block (PPSSDB) Offset (Byte) Field Description 0 Output Voltage 2 Source’s output voltage in 20mV units. When set to 0xFFFF, the Source does not support this field. 2 Output Current 1 Source’s output current in 50mA units. When set to 0xFF, the Source does not support this field. 3 Real Time Flags Bit Description 0 Reserved and Shall be set to zero 1...2 PTF  PTF: 00 – Not Supported  PTF: 01 – Normal  PTF: 10 – Warning  PTF: 11 – Over temperature 3 OMF OMF (Operating Mode Flag) is set when operating in Current Limit mode and cleared when operating in Constant Voltage mode. 4...7 Reserved and Shall be set to zero Extended Header Data Size = 4 PPSSDB (4-byte Data Block) Page 236 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.10.3 Real Time Flags Field Real Time flags provide a real-time indication of the Source's operating state:  The PTF (Present Temperature Flag) Shall provide a real-time indication of the Source's internal thermal status. If the PTF is not supported, it will be set to zero:  Normal indicates that the Source is operating within its normal thermal envelope.  Warning indicates that the Source is over-heating but is not in imminent danger of shutting down.  Over Temperature indicates that the Source is over heated and will shut down soon or has already shutdown and has sent the OTP Event flag in an Alert Message.  The OMF (Operating Mode Flag) Shall provide a real-time indication of the SPR PPS Source's operating mode. When set, the Source is operating in Current Limit mode; when cleared it is operating Constant Voltage mode. This bit Shall be set to zero when not in SPR PPS Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 237 6.5.11 Country_Codes Message The Country_Codes Message Shall be sent in response to a Get_Country_Codes Message. The Country_Codes Message enables a Port to query its Port Partner to get a list of alpha-2 country codes as defined in [ISO 3166] for which the Port Partner has country specific information. The Country_Codes Message Shall contain a 4…26-byte Country Code Data Block (CCDB) whose format Shall be as shown in Figure 6.50, "Country_Codes Message" and Table 6.63, "Country Codes Data Block (CCDB)". Figure 6.50 Country_Codes Message 6.5.11.1 Country Code Field The Country Code field Shall contain Length Country Codes in the Alpha-2 Country Code defined by [ISO 3166]. Table 6.63 Country Codes Data Block (CCDB) Offset Field Description 0 Length Number of country codes in the Message 1 Reserved Shall be set to zero. 2... Length * 2n Country Code Offset Field Description 2 1st Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 3 Second character of the Alpha-2 Country Code defined by [ISO 3166] 4 2nd Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 5 Second character of the Alpha-2 Country Code defined by [ISO 3166] … Length * 2n nth Country Code Extended Header Data Size = 4-26 CCDB (4-26 byte Data Block) Page 238 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.12 Country_Info Message The Country_Info Message Shall be sent in response to a Get_Country_Info Message. The Country_Info Message enables a Port to get additional country specific information from its Port Partner. The Country_Info Message Shall contain a 4…26-byte Country Info Data Block (CIDB) whose format Shall be as shown in Figure 6.51, "Country_Info Message" and Table 6.64, "Country Info Data Block (CIDB)". Figure 6.51 Country_Info Message 6.5.12.1 Country Code Field The Country Code field Shall contain the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 6.5.12.2 Country Specific Data Field The Country Specific Data field Shall contain content defined by and formatted in a manner determined by an official agency of the country indicated in the Country Code field. If the Country Code field in the Get_Country_Info Message is unrecognized then Country Specific Data field Shall return the null terminated ASCII text string "Unsupported Code". Table 6.64 Country Info Data Block (CIDB) Offset Field Size 0 Country Code First character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 1 Second character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message 2…3 Reserved Shall be set to zero. 4 Country Specific Data 1…22 bytes of content defined by the country’s authority. Extended Header Data Size = 4-26 CIDB (4-26 byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 239 6.5.13 Sink_Capabilities_Extended Message The Sink_Capabilities_Extended Message Shall be sent in response to a Get_Sink_Cap_Extended Message. The Sink_Capabilities_Extended Message enables a Sink or a DRP to inform the Source about its Capabilities as a Sink. The Sink_Capabilities_Extended Message Shall return a 24-byte Sink Capabilities Extended Data Block (SKEDB) whose format Shall be as shown in Figure 6.52, "Sink_Capabilities_Extended Message" and Table 6.65, "Sink Capabilities Extended Data Block (SKEDB)". Figure 6.52 Sink_Capabilities_Extended Message Table 6.65 Sink Capabilities Extended Data Block (SKEDB) Offset (Byte) Field Size (Bytes) Type Description 0 VID 2 Numeric Vendor ID (assigned by the USB-IF) 2 PID 2 Numeric Product ID (assigned by the manufacturer) 4 XID 4 Numeric Value provided by the USB-IF assigned to the product 8 FW Version 1 Numeric Firmware version number 9 HW Version 1 Numeric Hardware version number 10 SKEDB Version 1 Numeric SKEDB Version (not the specification Version):  Version 1.0 = 1 Values 0 and 2-255 are Reserved and Shall Not be used. 11 Load Step 1 Bit Field Bit Description 0...1  00b: 150mA/μs Load Step (default)  01b: 500mA/μs Load Step 11b…10b: Reserved and Shall Not be used. 2...7 Reserved and Shall be set to zero 12 Sink Load Characteristics 2 Bit Field Bit Description 0...4 Percent overload in 10% increments. Values higher than 25 (11001b) are clipped to 250%. 00000b is the default. 5...10 Overload period in 20ms when bits 0...4 non-zero. 1...14 Duty cycle in 5% increments when bits 0...4 are non-zero. 15 Can tolerate VBUS voltage droop 14 Compliance 1 Bit Field Bit Description 0 Requires LPS Source when set 1 Requires PS1 Source when set 2 Requires PS2 Source when set 3...7 Reserved and Shall be set to zero Extended Header Data Size = 24 SKEDB (24 byte Data Block) Page 240 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Sink's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.13.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Sink's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 15 Touch Temp 1 Value Temperature conforms to:  0 = Not applicable  1 = [IEC 60950-1] (default)  2 = [IEC 62368-1] TS1  3 = [IEC 62368-1] TS2 Note: All other values Reserved 16 Battery Info 1 Byte Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 17 Sink Modes 1 Bit Field Bit Description 0 PPS charging supported 1 VBUS powered 2 AC Supply powered 3 Battery powered 4 Battery essentially unlimited 5 AVS Support 6...7 Reserved and Shall be set to zero 18 SPR Sink Minimum PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 7 Reserved and Shall be set to zero 19 SPR Sink Operational PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its normal functionality. 7 Reserved and Shall be set to zero 20 SPR Sink Maximum PDP 1 Byte Bit Description 0...6 The maximum PDP the Sink will ever request. 7 Reserved and Shall be set to zero 21 EPR Sink Minimum PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 22 EPR Sink Operational PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its normal functionality. 23 EPR Sink Maximum PDP 1 Byte The maximum PDP that the EPR Sink will ever request. Table 6.65 Sink Capabilities Extended Data Block (SKEDB) (Continued) Offset (Byte) Field Size (Bytes) Type Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 241 6.5.13.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.13.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.13.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.13.6 SKEDB Version Field The SKEDB Version field contains the version level of the SKEDB. Currently only Version 1 is defined. 6.5.13.7 Load Step Field The Load Step field contains bits indicating the Load Step Slew Rate and Magnitude that this Sink prefers. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.13.8 Sink Load Characteristics Field The Sink Shall report its preferred load characteristics in the Sink Load Characteristics field. Regardless of this value, in operation its load Shall Not exceed the Capabilities reported in the Source_Capabilities_Extended Message. 6.5.13.9 Compliance Field The Compliance field Shall contain the types of Sources the Sink has been tested and certified with (see Section 7.1.12.3, "Compliance Field"). 6.5.13.10 Touch Temp The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Sink's enclosure. Safety limits for the Sink's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Sink May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.13.11 Battery Info The Battery Info field Shall report the number of Fixed Batteries and Hot Swappable Battery slots the Sink supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. The information reported in the Battery Info field Shall match that reported in the Number of Batteries/Battery Slots field of the Source_Capabilities_Extended Message. A Sink Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 242 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.12 Sink Modes The Sink Modes bit field Shall identify the charging Capabilities and the power sources that can be used by the Sink. When bit 0 is set, the Sink has the ability to use a PPS Source for fast charging. The source of power a Sink can use:  When bit 1 is set, the Sink has the ability to be sourced by VBUS.  When bit 2 is set, the Sink has the ability to be sourced by an AC Supply.  When bit 3 is set, the Sink has the ability to be sourced by a Battery.  When bit 4 is set, the Sink has the ability to be sourced by a Battery with essentially infinite energy (e.g., a car battery). Bits 1-4 May be set independently of one another. The combination indicates what sources of power the Sink can utilize. For example, some Sinks are only powered by a Battery (e.g., an automobile battery) rather than the more common AC Supply and some Sinks are only powered from VBUS or VCONN. When bit 5 is set, the Sink has the ability to support AVS. 6.5.13.13 SPR Sink Minimum PDP The SPR Sink Minimum PDP field Shall contain the minimum power Source PDP needed by the Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The SPR Sink Minimum PDP field Shall be less than or equal to the SPR Sink Operational PDP. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of SPR Sink Minimum PDP could be:  The minimum power a wireless Charger would require in order to detect, and deliver the minimum required amount of power to the attached device.  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device 6.5.13.14 SPR Sink Operational PDP The SPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The SPR Sink Operational PDP field Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), the SPR Sink Operational PDP field Shall correspond to the PDP Rating of the Charger shipped with the Sink or the recommended Charger's PDP Rating. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set the SPR Sink Minimum PDP field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 243 6.5.13.15 SPR Sink Maximum PDP The SPR Sink Maximum PDP field Shall contain the highest PDP the Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The SPR Sink Maximum PDP field Shall Not be less than the SPR Sink Operational PDP field, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. 6.5.13.16 EPR Sink Minimum PDP The EPR Sink Minimum PDP field Shall contain the Source PDP needed by an EPR Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery, if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The EPR Sink Minimum PDP field Shall be less than or equal to the EPR Sink Operational PDP field value. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of EPR Sink Minimum PDP could be:  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device. Note: EPR Sink Minimum PDP can be the same as its SPR Sink Minimum PDP. 6.5.13.17 EPR Sink Operational PDP The EPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of EPR Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The EPR Sink Operational PDP Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), it Shall correspond to the PDP Rating of the Charger shipped with the EPR Sink or the recommended Charger's PDP Rating. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. 6.5.13.18 EPR Sink Maximum PDP The EPR Sink Maximum PDP field Shall be highest PDP the EPR Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The EPR Sink Maximum PDP field Shall Not be less than the EPR Sink Operational PDP, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. Page 244 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.14 Extended_Control Message The Extended_Control Message extends the Control Message space. The Extended_Control Message includes one byte of data. The Extended_Control Message Shall be as shown in Figure 6.53, "Extended_Control Message" and Table 6.66, "Extended Control Data Block (ECDB)". Figure 6.53 Extended_Control Message The Extended_Control Message types are specified in the Type field of the ECDB and are listed in Table 6.67, "Extended Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets. 6.5.14.1 EPR_Get_Source_Cap Message The EPR_Get_Source_Cap (EPR Get Source Capabilities) Message Shall only be sent by a Port capable of operating as a Sink and that supports EPR Mode to request the Source Capabilities and Dual-Role Power capability of its Port Partner. A Port that can operate as an EPR Source Shall respond by returning an EPR_Source_Capabilities Message (see Section 6.5.15.2, "EPR_Source_Capabilities Message"). A Port that does not support EPR Mode as a Source Shall return the Not_Supported Message. An EPR Capable Sink Port that is operating in SPR Mode Shall treat the EPR_Source_Capabilities Message as informational only and Shall Not respond with an EPR_Request Message. 6.5.14.2 EPR_Get_Sink_Cap Message The EPR_Get_Sink_Cap (EPR Get Sink Capabilities) Message Shall only be sent by a Port capable of operating as a Source and that supports EPR Mode to request the Sink Capabilities and Dual-Role Power capability of its Port Partner. A Port that is EPR Capable operating as a Sink Shall respond by returning an EPR_Sink_Capabilities Message (see Section 6.5.15.3, "EPR_Sink_Capabilities Message"). A Port that does not support EPR Mode as a Sink Shall return the Not_Supported Message. Table 6.66 Extended Control Data Block (ECDB) Offset Field Value Description 0 Type Unsigned Int Extended Control Message Type 1 Data Byte Shall be set to zero when not used. Table 6.67 Extended Control Message Types Type Data Message Type Sent by Description Valid Start of Packet 0 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 Not used EPR_Get_Source_Cap Sink or DRP See Section 6.5.14.1 SOP only 2 Not used EPR_Get_Sink_Cap Source or DRP See Section 6.5.14.2 SOP only 3 Not used EPR_KeepAlive Sink See Section 6.5.14.3 SOP only 4 Not Used EPR_KeepAlive_Ack Source See Section 6.5.14.4 SOP only 5...255 Reserved All values not explicitly defined are Reserved and Shall Not be used. Extended Header Data Size = 2 ECDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 245 6.5.14.3 EPR_KeepAlive Message The EPR_KeepAlive Message May be sent by a Sink operating in EPR Mode to meet the requirement for periodic traffic. The Source operating on EPR Mode responds by returning an EPR_KeepAlive_Ack Message to the Sink. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.14.4 EPR_KeepAlive_Ack Message The EPR_KeepAlive_Ack Message Shall be sent by a Source operating in EPR Mode in response to an EPR_KeepAlive Message. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.15 EPR Capabilities Message The EPR Capabilities Message is an Extended Capabilities Message made of Power Data Objects (PDO) defined in Section 6.4.1, "Capabilities Message". It is used to form EPR_Source_Capabilities Messages and EPR_Sink_Capabilities Messages. Sources expose their EPR power Capabilities by sending an EPR_Source_Capabilities Message. Sinks expose their EPR power requirements by returning an EPR_Sink_Capabilities Message when requested. Both are composed of a number of 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). An EPR Capabilities Message Shall have a 5V Fixed Supply PDO containing the sending Port's information in the first object position followed by up to 10 additional PDOs. 6.5.15.1 EPR Capabilities Message Construction The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. See Figure 6.54, "Mapping SPR Capabilities to EPR Capabilities". Figure 6.54 Mapping SPR Capabilities to EPR Capabilities Power Data Objects in the EPR Capabilities Messages Shall be sent in the following order: 1) The SPR (A)PDOs as reported in the SPR Capabilities Message. The Number of Data Objects field in the Message Header of the EPR Capabilities Message is the same as the Number of Data Objects field in the Message Header of the SPR Capabilities Message. 2) If the SPR Capabilities Message contains fewer than 7 PDOs, the unused Data Objects Shall be zero filled. 3) The EPR (A)PDOs as defined in Section 6.4.1, "Capabilities Message" Shall start at Data Object position 8 and Shall be sent in the following order: a) Fixed Supply PDOs that offer 28V, 36V or 48V, if present, Shall be sent in voltage order; lowest to highest. b) One EPR AVS APDO Shall be sent. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 EPR PDO 8 EPR PDO 9 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 PDOs > 20V2 001b 010b 011b 100b 101b 110b 111b 1000b 1001b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b EPR PDO 10 EPR PDO 11 1010b 1011b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. 2) See Section 10 “Power Rules” for rules, on which EPR (A)PDOs are allowed be used for a given PDP. Page 246 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.15.2 EPR_Source_Capabilities Message The EPR_Source_Capabilities is an EPR Capabilities Message containing a list of Power Data Objects that the EPR Source is capable of supplying. It is sent by an EPR Source in order to convey its Capabilities to a Sink. An EPR Source Shall send the EPR_Source_Capabilities Message:  When entering EPR Mode  While in EPR Modes when its Capabilities change  In response to an EPR_Get_Source_Cap Message  After a Soft Reset while in EPR Mode An EPR Sink operating in EPR Mode Shall evaluate every EPR_Source_Capabilities Message it receives and Shall respond with a EPR_Request Message. If its power consumption exceeds the Source Capabilities, it Shall Re- negotiate so as not to exceed the Source's most recently Advertised Source Capabilities. While operating in SPR Mode, an EPR Sink receiving an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Messages Shall Not respond with an EPR_Request Message. The (A)PDOs in an EPR_Source_Capabilities Message Shall only be requested using the EPR_Request Message and only when in EPR Mode. When Source wants to exit EPR Mode, if not already in power contract with an SPR (A)PDO, it Shall send an EPR_Source_Capabilities Message with no EPR (A)PDOs (i.e. seven SPR (A)PDOs including any zero padded ones). See Figure 6.55, "EPR_Source_Capabilities message with no EPR PDOs". Figure 6.55 EPR_Source_Capabilities message with no EPR PDOs 6.5.15.3 EPR_Sink_Capabilities Message The EPR_Sink_Capabilities is an EPR Capabilities Message that contains a list of Power Data Objects that the EPR Sink requires to operate. It is sent by an EPR Sink in order to convey its power requirements to an EPR Source. The EPR Sink Shall only send the EPR_Sink_Capabilities Message in response to an EPR_Get_Sink_Cap Message. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 001b 010b 011b 100b 101b 110b 111b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 247 6.5.16 Vendor_Defined_Extended Message The Vendor_Defined_Extended Message (VDEM) is provided to allow vendors to exchange information outside of that defined by this specification using the Extended Message format. A Vendor_Defined_Extended Message Shall consist of at least one Vendor Data Object, the VDM Header, and May contain up to a maximum of 256 additional data bytes. To ensure vendor uniqueness of Vendor_Defined_Extended Messages, all Vendor_Defined_Extended Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. A VDEM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined_Extended Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. For example, a Vendor_Defined_Extended Message could be used to enable the Source to offer additional power via a Source_Capabilities Message. Vendor_Defined_Extended Messages Shall Not be used where equivalent functionality is contained in the PD Specification e.g., authentication or firmware update. The Message format Shall be as shown in Figure 6.56, "Vendor_Defined_Extended Message". Figure 6.56 Vendor_Defined_Extended Message The VDM Header Shall be the first 4-bytes in a Vendor Defined Extended Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. The VDM Header in the VDEM Shall follow the Unstructured VDM Header format as defined in Section 6.4.4.1, "Unstructured VDM". VDEMs Shall only be sent and received after an Explicit Contract has been established. A VDEM AMS Shall Not interrupt any other PD AMS. The VDEM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the SVID. The Port Partners and Cable Plugs Shall exit any states entered using a VDEM according to the rules defined in Section 6.4.4.3.4, "Enter Mode Command". The following rules apply to the use of VDEM Messages:  VDEMs Shall Not be initiated or responded to under any other circumstances than the following:  VDEMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract VDEMs Shall Not be sent and Shall be Ignored if received.  Cable Plugs Shall Not initiate VDEMs. Extended Header Data Size = 4...260 VDM Header VDEDB (0...256-byte Data Block) Page 248 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  VDEMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can VDEMs be sent or received. The Active Mode and the associated VDEMs Shall use the same SVID.  VDEMs May be used with SOP* Packets.  When a DFP or UFP does not support VDEMs or does not recognize the VID it Shall return a Not_Supported Message. Note: Usage of VDEMs with Chunking is not recommended since this is less efficient than using Unstructured VDMs.
6.6 - Timers.............................................................................................................................................. (Page 249)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 249 6.6 Timers All the following timers are defined in terms of bits on the bus regardless of where they are implemented in terms of the logical architecture. This is to ensure a fixed reference for the starting and stopping of timers. It is left to the implementer to ensure that this timing is observed in a real system. 6.6.1 CRCReceiveTimer The CRCReceiveTimer Shall be used by the sender's Protocol Layer to ensure that a Message has not been lost. Failure to receive an acknowledgment of a Message (a GoodCRC Message) whether caused by a bad GoodCRC Message on the receiving end or by a garbled Message within tReceive is detected when the CRCReceiveTimer expires. The sender's Protocol Layer response when a CRCReceiveTimer expires Shall be to retry nRetryCount times. Note: Cable Plugs do not retry Messages and large Extended Messages that are not Chunked are not retried (see Section 6.7.2, "Retry Counter"). Sending of the Preamble corresponding to the retried Message Shall start within tRetry of the CRCReceiveTimer expiring. The CRCReceiveTimer Shall be started when the last bit of the Message EOP has been transmitted by the PHY Layer. The CRCReceiveTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer. The Protocol Layer receiving a Message Shall respond with a GoodCRC Message within tTransmit in order to ensure that the sender's CRCReceiveTimer does not expire. The tTransmit time Shall be measured from when the last bit of the Message EOP has been received by the PHY Layer until the first bit of the Preamble of the GoodCRC Message has been transmitted by the PHY Layer. 6.6.2 SenderResponseTimer The SenderResponseTimer Shall be used by the sender's Policy Engine to ensure that a Message requesting a response (e.g., Get_Source_Cap Message) is responded to within a bounded time of tSenderResponse. Failure to receive the expected response is detected when the SenderResponseTimer expires. For Extended Messages received as Chunks, the SenderResponseTimer will also be started and stopped by the Chunking Rx State Machine. See Section 8.3.3.1.1, "SenderResponseTimer State Diagram" for more details of the SenderResponseTimer operation. The Policy Engine's response when the SenderResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The SenderResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the Message requesting a response, has been received by the PHY Layer. The SenderResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected response Message, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tReceiverResponse in order to ensure that the sender's SenderResponseTimer does not expire. The tReceiverResponse time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the expected request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.3 Capability Timers Sources and Sinks use Capability Timers to determine Attachment of a PD Capable device. By periodically sending or requesting Capabilities, it is possible to determine PD device Attachment when a response is received. Page 250 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.3.1 SourceCapabilityTimer Prior to the First Explicit Contract a Source Shall use the SourceCapabilityTimer to periodically send out a Source_Capabilities Message every tTypeCSendSourceCap while:  The Port is Attached.  The Source is not in an active connection with a PD Sink Port. Whenever there is a SourceCapabilityTimer timeout the Source Shall send a Source_Capabilities Message. It Shall then re-initialize and restart the SourceCapabilityTimer. The SourceCapabilityTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer since a PD connection has been established. At this point, the Source waits for a Request Message or a response timeout. Note: The Source can also stop sending Source_Capabilities Message after nCapsCount Messages have been sent without a GoodCRC Message response (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.2, "Policy Engine Source Port State Diagram" for more details of when Source_Capabilities Messages are transmitted. 6.6.3.2 SinkWaitCapTimer The Sink Shall support the SinkWaitCapTimer. While in a Default Contract or an Implicit Contract when a Sink observes an absence of Source_Capabilities Messages, after VBUS is present, for a duration of tTypeCSinkWaitCap the Sink May issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter") or continue to operate at USB Type-C current. When a Sink, entering EPR Mode, observes an absence of EPR_Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to exit EPR Mode (see Section 6.4.10, "EPR_Mode Message"). When a Sink, exiting EPR Mode, observes an absence of Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.3, "Policy Engine Sink Port State Diagram" for more details of when the SinkWaitCapTimer is run. 6.6.3.3 tFirstSourceCap After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap a Source Shall send its first Source_Capabilities Message within tFirstSourceCap of VBUS reaching vSafe5V. After Soft Reset, a Source Shall send its first Source Capabilities Message within tFirstSourceCap after last bit of the GoodCRC Message EOP corresponding to Accept Message. This ensures that the Sink receives a Source Capabilities Message before the Sink's SinkWaitCapTimer expires. A Source entering EPR Mode Shall send its first EPR_Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded). A Source exiting EPR Mode Shall send its first Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 251 6.6.4 Wait Timers and Times 6.6.4.1 SinkRequestTimer The SinkRequestTimer is used to ensure that the time before the next Sink Request Message, after a Wait Message has been received from the Source in response to a Sink Request Message, is a minimum of tSinkRequest min (see Section 6.3.12, "Wait Message"). The SinkRequestTimer Shall be started when the EOP of a Wait Message has been received and Shall be stopped if any other Message is received or during a Hard Reset. The Sink Shall wait at least tSinkRequest, after receiving the EOP of a Wait Message sent in response to a Sink Request Message, before sending a new Request Message. Whenever there is a SinkRequestTimer timeout the Sink May send a Request Message. It Shall then re-initialize and restart the SinkRequestTimer. 6.6.4.2 tPRSwapWait The time before the next PR_Swap Message, after a Wait Message has been received in response to a PR_Swap Message is a minimum of tPRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tPRSwapWait after receiving the EOP of a Wait Message sent in response to a PR_Swap Message, before sending a new PR_Swap Message. 6.6.4.3 tDRSwapWait The time before the next DR_Swap Message, after a Wait Message has been received in response to a DR_Swap Message is a minimum of tDRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tDRSwapWait after receiving the EOP of a Wait Message sent in response to a DR_Swap Message, before sending a new DR_Swap Message. 6.6.4.4 tVCONNSwapWait The time before the next VCONN_Swap Message, after a Wait Message has been received in response to a VCONN_Swap Message is a minimum of tVCONNSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tVCONNSwapWait after receiving the EOP of a Wait Message sent in response to a VCONN_Swap Message, before sending a new VCONN_Swap Message. 6.6.4.5 tVCONNSwapDelayDFP The time delay for DFP after losing VCONN Source role due to an incoming VCONN Swap request from UFP and before sending the next VCONN_Swap Message. The DFP Shall wait at least tVCONNSwapDelayDFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.6 tVCONNSwapDelayUFP The time delay for UFP after losing VCONN Source role due to an incoming VCONN Swap request from DFP and before sending the next VCONN_Swap Message. The UFP Shall wait at least tVCONNSwapDelayUFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.7 tEnterUSBWait The time before the next Enter_USB Message, after a Wait Message has been received in response to a Enter_USB Message is a minimum of tEnterUSBWait min (see Section 6.3.12, "Wait Message"). The DFP Shall wait at least tEnterUSBWait after receiving the EOP of a Wait Message sent in response to an Enter_USB Message, before sending a new Enter_USB Message. 6.6.5 Power Supply Timers See Section 7.3, "Transitions" for diagrams showing the usage of the timers in this section. Page 252 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.5.1 PSTransitionTimer The PSTransitionTimer is used by the Policy Engine to timeout on a PS_RDY Message. It is started when a request for new Source Capabilities has been accepted and will timeout after tPSTransition if a PS_RDY Message has not been received. This condition leads to a Hard Reset and a return to USB Default Operation. The PSTransitionTimer relates to the time taken for the Source to transition from one voltage, or current level, to another (see Section 7.1, "Source Requirements"). The PSTransitionTimer Shall be started when the last bit of the GoodCRC Message EOP, corresponding to an Accept Message, has been transmitted by the PHY Layer. The PSTransitionTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer. 6.6.5.2 PSSourceOffTimer 6.6.5.2.1 Use during Power Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is currently acting as a Sink to timeout on a PS_RDY Message during a Power Role Swap AMS. This condition leads to USB Type-C Error Recovery. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Source the Sink can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this transmitted Accept Message, is received by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Sink the Source can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this received Accept Message, is transmitted by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the remote Dual-Role Power Device to stop supplying power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the remote Dual-Role Power Device within tPSSourceOff indicating this has occurred. 6.6.5.2.2 Use during Fast Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is the Initial Sink (currently providing vSafe5V) to timeout on a PS_RDY Message during a Fast Role Swap AMS. This condition leads to USB Type-C Error Recovery. When the FR_Swap Message request has been sent by the Initial Sink, the Initial Source Shall respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this Accept Message is received by the Initial Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the Initial Source to stop supplying power and for VBUS to revert to vSafe5V (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the Initial Source within tPSSourceOff indicating this has occurred. 6.6.5.3 PSSourceOnTimer 6.6.5.3.1 Use during Power Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Power Role Swap. This condition leads to USB Type-C Error Recovery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 253 The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer.  The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.5.3.2 Use during Fast Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Fast Role Swap. This condition leads to USB Type-C Error Recovery. The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer. The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.6 NoResponseTimer The NoResponseTimer is used by the Policy Engine in a Source to determine that its Port Partner is not responding after a Hard Reset. When the NoResponseTimer times out, the Policy Engine Shall issue up to nHardResetCount additional Hard Resets before determining that the Port Partner is non-responsive to USB Power Delivery messaging. If the Source fails to receive a GoodCRC Message in response to a Source_Capabilities Message within tNoResponse of:  The last bit of a Hard Reset Signaling being sent by the PHY Layer if the Hard Reset Signaling was initi- ated by the Sink.  The last bit of a Hard Reset Signaling being received by the PHY Layer if the Hard Reset Signaling was initiated by the Source. Then the Source Shall issue additional Hard Resets up to nHardResetCount times (see Section 6.8.3, "Hard Reset"). For a non-responsive device, the Policy Engine in a Source May either decide to continue sending Source_Capabilities Messages or to go to non-USB Power Delivery operation and cease sending Source_Capabilities Messages. 6.6.7 BIST Timers 6.6.7.1 tBISTCarrierMode tBISTCarrierMode is used to define the maximum time that a UUT has to enter BIST Carrier Mode when requested by a Tester. Page 254 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A UUT Shall enter BIST Carrier Mode within tBISTCarrierMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. In BIST Carrier Mode when transmitting a continuous carrier signal transmission Shall start as soon as the UUT enters BIST Mode. 6.6.7.2 BISTContModeTimer The BISTContModeTimer is used by a UUT to ensure that a Continuous BIST Mode (i.e., BIST Carrier Mode) is exited in a timely fashion. A UUT that has been put into a Continuous BIST Mode Shall return to normal operation (either PE_SRC_Transition_to_default, PE_SNK_Transition_to_default, or PE_CBL_Ready) within tBISTContMode of starting to transmit a continuous carrier signal. 6.6.7.3 tBISTSharedTestMode tBISTSharedTestMode is used to define the maximum time that a UUT has to enter BIST Shared Capacity Test Mode when requested by a Tester. A UUT Shall enter BIST Shared Capacity Test Mode and send a new Source_Capabilities Message from all Ports within the Shared Capacity Group within tBISTSharedTestMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. 6.6.8 Power Role Swap Timers 6.6.8.1 SwapSourceStartTimer The SwapSourceStartTimer Shall be used by the New Source, after a Power Role Swap or Fast Role Swap, to ensure that it does not send Source_Capabilities Message before the New Sink is ready to receive the Source_Capabilities Message. The New Source Shall Not send the Source_Capabilities Message earlier than tSwapSourceStart after the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. The Sink Shall be ready to receive a Source_Capabilities Message tSwapSinkReady after having sent the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. 6.6.9 Soft Reset Timers 6.6.9.1 tSoftReset A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure. This Shall cause the Source or Sink to send a Soft_Reset Message, transmission of which Shall be completed within tSoftReset of the CRCReceiveTimer expiring. 6.6.9.2 tProtErrSoftReset If the Protocol Error occurs that causes the Source or Sink to send a Soft_Reset Message, the transmission of the Soft_Reset Message Shall be completed within tProtErrSoftReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.10 Data Reset Timers 6.6.10.1 VCONNDischargeTimer The VCONNDischargeTimer is used by the Policy Engine in the DFP to ensure the UFP actively discharges VCONN in a timely manner to ensure the cable will restore Ra. Once the UFP has discharged VCONN below vRaReconnect (see [USB Type-C 2.4]) it sends a PS_RDY Message (see also Section 7.1.15, "VCONN Power Cycle"). If the DFP does not receive a PS_RDY Message from the UFP within tVCONNSourceDischarge of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message, the VCONNDischargeTimer will time out and the Policy Engine Shall enter the ErrorRecovery State. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 255 6.6.10.2 tDataReset The DFP Shall complete the Data_Reset process (as defined in Section 6.3.14, "Data_Reset Message") within tDataReset of the last bit of the GoodCRC Message EOP, corresponding to the Accept Message, being transmitted by the PHY Layer. 6.6.10.3 DataResetFailTimer The DataResetFailTimer Shall be used by the DFP's Policy Engine to ensure the Data Reset process completes within tDataResetFail of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the DFP's DataResetFailTimer expires, the DFP Shall enter the ErrorRecovery State. 6.6.10.4 DataResetFailUFPTimer The DataResetFailUFPTimer Shall be used by the UFP's Policy Engine to ensure the Data Reset process completes within tDataResetFailUFP of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the UFP's DataResetFailUFPTimer expires, the UFP Shall enter the ErrorRecovery State. 6.6.11 Hard Reset Timers 6.6.11.1 HardResetCompleteTimer The HardResetCompleteTimer is used by the Protocol Layer in the case where it has asked the PHY Layer to send Hard Reset Signaling and the PHY Layer is unable to send the Signaling within a reasonable time due to a non-Idle channel. If the PHY Layer does not indicate that the Hard Reset Signaling has been sent within tHardResetComplete of the Protocol Layer requesting transmission, then the Protocol Layer Shall inform the Policy Engine that the Hard Reset Signaling has been sent in order to ensure the power supply is reset in a timely fashion. 6.6.11.2 PSHardResetTimer The PSHardResetTimer is used by the Policy Engine in a Source to ensure that the Sink has had sufficient time to process Hard Reset Signaling before turning off its power supply to VBUS. When a Hard Reset occurs the Source, stops driving VCONN, removes Rp from the CC pin and starts to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. See Section 7.1.5, "Response to Hard Resets". 6.6.11.3 tDRSwapHardReset If a DR_Swap Message is received during Modal Operation then a Hard Reset Shall be initiated by the recipient of the unexpected DR_Swap Message; Hard Reset Signaling Shall be generated within tDRSwapHardReset of the EOP of the GoodCRC sent in response to the DR_Swap Message. 6.6.11.4 tProtErrHardReset If a Protocol Error occurs that directly leads to a Hard Reset, the transmission of the Hard Reset Signaling Shall be completed within tProtErrHardReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.12 Structured VDM Timers 6.6.12.1 VDMResponseTimer The VDMResponseTimer Shall be used by the Initiator's Policy Engine to ensure that a Structured VDM Command request needing a response (e.g. Discover Identity Command request) is responded to within a bounded time of tVDMSenderResponse. The VDMResponseTimer Shall be applied to all Structured VDM Commands except the Page 256 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Enter Mode and Exit Mode Commands which have their own timers (VDMModeEntryTimer and VDMModeExitTimer respectively). Failure to receive the expected response is detected when the VDMResponseTimer expires. The Policy Engine's response when the VDMResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The VDMResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected VDM Command response, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMReceiverResponse in order to ensure that the sender's VDMResponseTimer does not expire. The tVDMReceiverResponse time Shall be measured from the time the last bit of the Message EOP has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.2 VDMModeEntryTimer The VDMModeEntryTimer Shall be used by the Initiator's Policy Engine to ensure that the response to a Structured VDM Enter Mode Command request (ACK or NAK with ACK indicating that the requested Alternate Mode has been entered) arrives within a bounded time of tVDMWaitModeEntry. Failure to receive the expected response is detected when the VDMModeEntryTimer expires. The Policy Engine's response when the VDMModeEntryTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.1, "DFP Structured VDM Mode Entry State Diagram"). The VDMModeEntryTimer Shall be started from the time the last bit of the EOP of the GoodCRC Message, corresponding to the VDM Command request, has been received by the PHY Layer. The VDMModeEntryTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected Structured VDM Command response (ACK, NAK or BUSY), has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMEnterMode in order to ensure that the sender's VDMModeEntryTimer does not expire. The tVDMEnterMode time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to VDM Command Request, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.3 VDMModeExitTimer The VDMModeExitTimer Shall be used by the Initiator's Policy Engine to ensure that the ACK response to a Structured VDM Exit Mode Command, indicating that the requested Alternate Mode has been exited, arrives within a bounded time of tVDMWaitModeExit. Failure to receive the expected response is detected when the VDMModeExitTimer expires. The Policy Engine's response when the VDMModeExitTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.2, "DFP Structured VDM Mode Exit State Diagram"). The VDMModeExitTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMModeExitTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the expected Structured VDM Command response ACK, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMExitMode in order to ensure that the sender's VDMModeExitTimer does not expire. The tVDMExitMode time Shall be measured from the time the last bit of the Message EOP has been received by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 257 6.6.12.4 tVDMBusy The Initiator Shall wait at least tVDMBusy, after receiving a BUSY Command response, before repeating the Structured VDM request again. 6.6.13 VCONN Timers 6.6.13.1 VCONNOnTimer The VCONNOnTimer is used during a VCONN Swap. The VCONNOnTimer Shall be started when:  The last bit of GoodCRC Message EOP, corresponding to the Accept Message, is transmitted or received by the PHY Layer. The VCONNOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, is transmitted by the PHY Layer. Prior to sending the PS_RDY Message, the Port Shall have turned VCONN On. 6.6.13.2 tVCONNSourceOff The tVCONNSourceOff time applies during a VCONN Swap. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, being transmitted by the PHY Layer. 6.6.14 tCableMessage Ports compliant with Revision 3.x of the specification Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet even when communicating using [USBPD 2.0] with a Cable Plug. This specification defines Collision Avoidance mechanisms that obviate the need for this time. Cable Plugs Shall only wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet when operating at [USBPD 2.0]. When operating at Revisions higher than [USBPD 2.0] Cable Plugs Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet. 6.6.15 DiscoverIdentityTimer The DiscoverIdentityTimer is used prior to or during an Explicit Contract when discovering whether a Cable Plug is PD Capable using SOP’. When performing Cable Discovery during an Explicit Contract the Discover Identity Command request Shall be sent every tDiscoverIdentity. No more than nDiscoverIdentityCount Discover Identity Messages without a GoodCRC Message response Shall be sent. If no GoodCRC Message response is received after nDiscoverIdentityCount Discover Identity Command requests have been sent by a Port, the Port Shall Not send any further SOP’/SOP’’ Messages. 6.6.16 Collision Avoidance Timers 6.6.16.1 SinkTxTimer The SinkTxTimer is used by the Protocol Layer in a Source to allow the Sink to complete its transmission before initiating an AMS. The Source Shall wait a minimum of tSinkTx after changing Rp from SinkTxOK to SinkTxNG before initiating an AMS by sending a Message. A Sink Shall only initiate an AMS when it has determined that Rp is set to SinkTxOK. Page 258 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.16.2 tSrcHoldsBus If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. 6.6.17 Fast Role Swap Timers 6.6.17.1 tFRSwap5V The tFRSwap5V time Shall be measured from:  The later of:  The last bit of the GoodCRC Message EOP, corresponding to the Accept Message or  VBUS being within vSafe5V.  Until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. During a Fast Role Swap, the Initial Source Shall start the PS_RDY Message within tFRSwap5V after both:  The Initial Source has sent the Accept Message, and  VBUS is at or below vSafe5V. 6.6.17.2 tFRSwapComplete During a fast-role swap, the Initial Sink Shall respond with a the PS_RDY Message within tFRSwapComplete after it has received the PS_RDY Message from the Initial Source. The tFRSwapComplete time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. 6.6.17.3 tFRSwapInit That last bit of the EOP of the FR_Swap Message Shall be transmitted by the New Source no later than tFRSwapInit after the Fast Role Swap Request has been detected (see Section 5.8.6.3, "Fast Role Swap Detection"). 6.6.18 Chunking Timers 6.6.18.1 ChunkingNotSupportedTimer The ChunkingNotSupportedTimer is used by a Source or Sink which does not support multi-chunk Chunking but has received a Message Chunk. The ChunkingNotSupportedTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to a Message Chunk of a multi-chunk Message, is transmitted by the PHY Layer. The Policy Engine Shall Not send its Not_Supported Message before the ChunkingNotSupportedTimer expires. 6.6.18.2 ChunkSenderRequestTimer The ChunkSenderRequestTimer is used during a Chunked Message transmission. The ChunkSenderRequestTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Response is responded to within a bounded time of tChunkSenderRequest. Failure to receive the expected response is detected when the ChunkSenderRequestTimer expires. The ChunkSenderRequestTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is received by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 259 The ChunkSenderRequestTimer Shall be stopped when:  The last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, is trans- mitted by the PHY Layer.  A Message other than a Chunk Request is received from the Protocol Layer Rx. The receiver of a Chunk Response requiring a Chunk Request Shall respond with a Chunk Request within tChunkReceiverRequest in order to ensure that the sender's ChunkSenderRequestTimer does not expire. The tChunkReceiverRequest time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Response Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.18.3 ChunkSenderResponseTimer The ChunkSenderResponseTimer is used during a Chunked Message transmission. The ChunkSenderResponseTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Request is responded to within a bounded time of tChunkSenderResponse. Failure to receive the expected response is detected when the ChunkSenderResponseTimer expires. The ChunkSenderResponseTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Request Message, is received by the PHY Layer. The ChunkSenderResponseTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is transmitted by the PHY Layer.  A Message other than a Chunk is received from the Protocol Layer. The receiver of a Chunk Request requiring a Chunk Response Shall respond with a Chunk Response within tChunkReceiverResponse in order to ensure that the sender's ChunkSenderResponseTimer does not expire. The tChunkReceiverResponse time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.19 Programmable Power Supply Timers 6.6.19.1 SinkPPSPeriodicTimer The SinkPPSPeriodicTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSRequest when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is sent periodically as a keep alive mechanism. SinkPPSPeriodicTimer Shall be re-initialized and restarted on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any received Message, that causes the Sink to enter the PE_SNK_Ready state. The Sink Shall stop the SinkPPSPeriodicTimer on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any Message, or the last bit of any Signaling is received, by the PHY Layer, from the Source and by the Sink that causes the Sink to leave the PE_SNK_Ready state. 6.6.19.2 SourcePPSCommTimer The SourcePPSCommTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSTimeout when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is received periodically as a keep alive mechanism. Page 260 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SourcePPSCommTimer Shall be re-initialized and restarted when, after receiving any Message that causes the Source to enter the PE_SRC_Ready state, the last bit of the corresponding GoodCRC Message EOP is transmitted by the PHY Layer. The Source Shall stop the SourcePPSCommTimer when:  After receiving any Message that causes the Source to leave the PE_SRC_Ready state, the last bit of the of the corresponding GoodCRC Message EOP is sent by the PHY Layer, or  The last bit of any Signaling is received by the PHY Layer from the Sink by the Source that causes the Source to leave the PE_SRC_Ready state. When the SourcePPSCommTimer times out the Source Shall issue Hard Reset Signaling. 6.6.20 tEnterUSB The DFP Shall send the Enter_USB Message within tEnterUSB of either:  The last bit of the GoodCRC acknowledging the Data_Reset_Complete Message in response to the Data_Reset Message or  A PD Connection, specifically the last bit of the GoodCRC acknowledging the Source_Capabilities Mes- sage after the initial entry into the PE_SRC_Send_Capabilities state or  The last bit of the GoodCRC acknowledging the Accept Message in response to the DR_Swap Message Failure by the DFP to meet this timeout parameter can result in the ports not transitioning into [USB4] operation. Any AMS initiated by the UFP prior to receiving the Enter_USB Message will delay reception of the Enter_USB Message and [USB4] operation, therefore a USB4® -capable UFP Should Not initiate any AMS until the DFP has been given time to send the Enter_USB Message. 6.6.21 EPR Timers 6.6.21.1 SinkEPREnterTimer Timer The SinkEPREnterTimer is used to ensure the EPR Mode entry process completes within tEnterEPR. The Sink Shall start the timer when it sees the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 1 (Enter). The Sink Shall stop the timer when the last bit of the corresponding GoodCRC Message EOP, corresponding to the received EPR_Mode Message with the Action field set to 3 (Enter Succeeded), has been transmitted by the PHY Layer. If the timer expires the Sink Shall send a Soft_Reset Message. 6.6.21.2 SinkEPRKeepAlive Timer The SinkEPRKeepAliveTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSinkEPRKeepAlive. The Sink Shall initialize and run this timer upon entry into the PE_SNK_Ready State when in EPR Mode and Shall stop it upon exit from the PE_SNK_Ready when in EPR Mode. While operating in EPR Mode, the Sink Shall stop the SinkEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Source, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Sink Shall send an EPR_KeepAlive Message. 6.6.21.3 SourceEPRKeepAlive Timer The SourceEPRKeepAliveTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSourceEPRKeepAlive. The Source Shall initialize Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 261 and run this timer upon entry into the PE_SRC_Ready State when in EPR Mode and Shall disable it upon exit from the PE_SRC_Ready State when EPR Mode. While operating in EPR Mode, the Source Shall stop the SourceEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Sink, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Source Shall send Hard Reset Signaling. 6.6.21.4 tEPRSourceCableDiscovery After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap an EPR Source Shall discover the Cable Plug within tEPRSourceCableDiscovery of entering the First Explicit Contract. The EPR Source Shall send the Discover Identity REQ Command, to the Cable Plug, within tEPRSourceCableDiscovery of receiving the GoodCRC Message acknowledging the PS_RDY Message as part of the Explicit Contract Negotiation. Note: If the EPR Source is not the VCONN Source, tEPRSourceCableDiscovery, will also include the time needed for the VCONN Swap. Page 262 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.22 Time Values and Timers Table 6.68, "Time Values" summarizes the values for the timers listed in this section. For each Timer Value, a given implementation Shall pick a fixed value within the range specified. Table 6.69, "Timers" lists the timers. Table 6.68 Time Values Parameter Value (min) Value (Nom) Value (max) Units Reference tACTempUpdate 500 ms Section 6.5.2.2.1 tBISTContMode 30 45 60 ms Section 6.6.7.2 tBISTCarrierMode 300 ms Section 6.6.7.1 tBISTSharedTestMode 1 s Section 6.6.7.3 tCableMessage 750 µs Section 6.6.14 tCapabilitiesMismatchResponse 2 s Section 6.4.2.3 tChunkingNotSupported 40 45 50 ms Section 6.6.18.1 tChunkReceiverRequest 15 ms Section 6.6.18.2 tChunkReceiverResponse 15 ms Section 6.6.18.3 tChunkSenderRequest 24 27 30 ms Section 6.6.18.2 tChunkSenderResponse 24 27 30 ms Section 6.6.18.3 tDataReset 200 225 250 ms Section 6.6.10.2 tDataResetFail 300 400 ms Section 6.6.10.3 tDataResetFailUFP 450 550 ms Section 6.6.10.4 tDiscoverIdentity 40 50 ms Section 6.6.14 tDRSwapHardReset 15 ms Section 6.6.11.3 tDRSwapWait 100 ms Section 6.6.4.3 tEnterUSB 500 ms Section 6.6.20 tEnterUSBWait 100 ms Section 6.6.4.7 tEnterEPR 450 500 550 ms Section 6.6.21.1 tEPRSourceCableDiscovery 2 s Section 6.6.21.4 tFirstSourceCap 250 ms Section 6.6.3.3 tFRSwap5V 15 ms Section 6.6.17.1 tFRSwapComplete 15 ms Section 6.6.17.2 tFRSwapInit 15 ms Section 6.6.17.3 tHardReset 5 ms Section 6.3.13 tHardResetComplete 4 4.5 5 ms Section 6.6.9 tSourceEPRKeepAlive 0.750 0.875 1.000 s Section 6.6.21.3 tSinkEPRKeepAlive 0.250 0.375 0.500 s Section 6.6.21.2 tNoResponse 4.5 5.0 5.5 s Section 6.6.6 tPPSRequest 10 s Section 6.6.19.1 tPPSTimeout 12.0 13.5 15.0 s Section 6.6.19.2 tProtErrHardReset 15 ms Section 6.6.11.4 tProtErrSoftReset 15 ms Section 6.6.9.2 tPRSwapWait 100 ms Section 6.6.4.2 tPSHardReset 25 30 35 ms Section 6.6.11.2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 263 tPSSourceOff SPR Mode 750 835 920 ms Section 6.6.5.2 EPR Mode 1120 1260 1400 tPSSourceOn SPR Mode 390 435 480 ms Section 6.6.5.3 tPSTransition SPR Mode 450 500 550 ms Section 6.6.5.1 EPR Mode 830 925 1020 tReceive 0.9 1.0 1.1 ms Section 6.6.1 tReceiverResponse 15 ms Section 6.6.2 tRetry 195 µs Section 6.6.1 tSenderResponse 27 30 33 ms Section 6.6.2 tSinkDelay 5 ms Section 5.7 tSinkRequest 100 ms Section 6.6.4.1 tSinkTx 16 18 20 ms Section 6.6.16 tSoftReset 15 ms Section 6.8.1 tSrcHoldsBus 50 ms Section 8.3.3.2 tSwapSinkReady 15 ms Section 6.6.8.1 tSwapSourceStart 20 ms Section 6.6.8.1 tTransmit 195 µs Section 6.6.1 tTypeCSendSourceCap 100 150 200 ms Section 6.6.3.1 tTypeCSinkWaitCap 310 465 620 ms Section 6.6.3.2 tVCONNSourceDischarge 160 200 240 ms Section 6.6.10.1 tVCONNSourceOff 25 ms Section 6.6.13 tVcONNSourceOn 50 ms Section 6.3.11 tVCONNSourceTimeout 100 150 200 ms Section 6.6.13 tVCONNSwapWait 100 ms Section 6.6.4.4 tVCONNSwapDelayDFP 100 ms Section 6.6.4.5 tVCONNSwapDelayUFP 500 ms Section 6.6.4.6 tVDMBusy 50 ms Section 6.6.12.4 tVDMEnterMode 25 ms Section 6.6.12.2 tVDMExitMode 25 ms Section 6.6.12.3 tVDMReceiverResponse 15 ms Section 6.6.12.1 tVDMSenderResponse 24 27 30 ms Section 6.6.12.1 tVDMWaitModeEntry 40 45 50 ms Section 6.6.12.2 tVDMWaitModeExit 40 45 50 ms Section 6.6.12.3 Table 6.68 Time Values (Continued) Parameter Value (min) Value (Nom) Value (max) Units Reference Page 264 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.69 Timers Timer Parameter Used By Reference BISTContModeTimer tBISTContMode Policy Engine Section 6.6.7.2 ChunkingNotSupportedTimer tChunkingNotSupported Policy Engine Section 6.6.18.1 ChunkSenderRequestTimer tChunkSenderRequest Protocol Layer Section 6.6.18.2 ChunkSenderResponseTimer tChunkSenderResponse Protocol Layer Section 6.6.18.3 CRCReceiveTimer tReceive Protocol Layer Section 6.6.1 DataResetFailTimer tDataResetFail Policy Engine Section 6.6.10.3 DataResetFailUFPTimer tDataResetFailUFP Policy Engine Section 6.6.10.4 DiscoverIdentityTimer tDiscoverIdentity Policy Engine Section 6.6.15 HardResetCompleteTimer tHardResetComplete Protocol Layer Section 6.6.9 NoResponseTimer tNoResponse Policy Engine Section 6.6.6 PSHardResetTimer tPSHardReset Policy Engine Section 6.6.11.2 PSSourceOffTimer tPSSourceOff Policy Engine Section 6.6.5.2 PSSourceOnTimer tPSSourceOn Policy Engine Section 6.6.5.3 PSTransitionTimer tPSTransition Policy Engine Section 6.6.5.1 SenderResponseTimer tSenderResponse Policy Engine Section 6.6.2 SinkEPREnterTimer tEnterEPR Policy Engine Section 6.6.21.1 SinkEPRKeepAliveTimer tSinkEPRKeepAlive Policy Engine Section 6.6.21.2 SinkPPSPeriodicTimer tPPSRequest Policy Engine Section 6.6.19.1 SinkRequestTimer tSinkRequest Policy Engine Section 6.6.4 SinkWaitCapTimer tTypeCSinkWaitCap Policy Engine Section 6.6.3.2 SourceCapabilityTimer tTypeCSendSourceCap Policy Engine Section 6.6.3.1 SourceEPRKeepAliveTimer tSourceEPRKeepAlive Policy Engine Section 6.6.21.3 SourcePPSCommTimer tPPSTimeout Policy Engine Section 6.6.19.2 SinkTxTimer tSinkTx Protocol Layer Section 6.6.16 SwapSourceStartTimer tSwapSourceStart Policy Engine Section 6.6.8.1 VCONNDischargeTimer tVCONNSourceDischarge Policy Engine Section 6.6.10.1 VCONNOnTimer tVCONNSourceTimeout Policy Engine Section 6.6.13.1 VDMModeEntryTimer tVDMWaitModeEntry Policy Engine Section 6.6.12.2 VDMModeExitTimer tVDMWaitModeExit Policy Engine Section 6.6.12.3 VDMResponseTimer tVDMSenderResponse Policy Engine Section 6.6.12.1
6.7 - Counters.......................................................................................................................................... (Page 265)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 265 6.7 Counters 6.7.1 MessageID Counter The MessageIDCounter is a rolling counter, ranging from 0 to nMessageIDCount, used to detect duplicate Messages. This value is used for the MessageID field in the Message Header of each transmitted Message. Each Port Shall maintain a copy of the last MessageID value received from its Port Partner. Devices that support multiple ports, such as Hubs, Shall maintain copies of the last MessageID on a per Port basis. A Port which communicates using SOP* Packets Shall maintain copies of the last MessageID for each type of SOP* it uses. The transmitter Shall use the MessageID in a GoodCRC Message to verify that a particular Message was received correctly. The receiver Shall use the MessageID to detect duplicate Messages. 6.7.1.1 Transmitter Usage The Transmitter Shall use the MessageID as follows:  Upon receiving either Hard Reset Signaling, or a Soft_Reset Message, the transmitter Shall set its MessageIDCounter to zero and re-initialize its retry mechanism.  If a GoodCRC Message with a MessageID matching the MessageIDCounter is not received before the CRCReceiveTimer expires, it Shall retry the same Packet up to nRetryCount times using the same MessageID.  If a GoodCRC Message is received with a MessageID matching the current MessageIDCounter before the CRCReceiveTimer expires, the transmitter Shall re-initialize its retry mechanism and increment its MessageIDCounter.  If the Message is aborted by the Policy Engine, the transmitter Shall delete the Message from its transmit buffer, re-initialize its retry mechanism and increment its MessageIDCounter. 6.7.1.2 Receiver Usage The Receiver Shall use the MessageID as follows:  When the first good Packet is received after a reset, the receiver Shall store a copy of the received MessageID value.  For subsequent Messages, if MessageID value in a received Message is the same as the stored value, the receiver Shall return a GoodCRC Message with that MessageID value and drop the Message (this is a retry of an already received Message). Note: This Shall Not apply to the Soft_Reset Message which always has a MessageID value of zero.  If MessageID value in the received Message is different than the stored value, the receiver Shall return a GoodCRC Message with the new MessageID value, store a copy of the new MessageID value and pro- cess the Message. 6.7.2 Retry Counter The RetryCounter is used by a Port whenever there is a Message transmission failure (timeout of CRCReceiveTimer). If the nRetryCount retry fails, then the link Shall be reset using the Soft Reset mechanism. The following rules apply to retries when there is a Message transmission failure (see also Section 6.12.2.2, "Protocol Layer Message Transmission"):  Cable Plugs Shall Not retry Messages.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are not Chunked (Chunked flag set to zero) Shall Not be retried. Page 266 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Extended Messages of Data Size ≤ MaxExtendedMsgLegacyLen (Chunked flag set to zero or one) Shall be retried.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are Chunked (Chunked flag set to one) individual Chunks Shall be retried. When Messages are not retried, then the RetryCounter is not used. Higher layer protocols are expected to accommodate Message delivery failure or failure to receive a GoodCRC Message. 6.7.3 Hard Reset Counter The HardResetCounter is used to retry the Hard Reset whenever there is no response from the remote device (see Section 6.6.6, "NoResponseTimer"). Once the Hard Reset has been retried nHardResetCount times then it Shall be assumed that the remote device is non-responsive. 6.7.4 Capabilities Counter The CapsCounter is used to count the number of Source_Capabilities Messages which have been sent by a Source at power up or after a Hard Reset. Implementation of the CapsCounter is Optional but May be used by any Source which wishes to preserve power by not sending Source_Capabilities Messages after a period of time. When the CapsCounter is implemented and the Source detects that a Sink is Attached then after nCapsCount Source_Capabilities Messages have been sent the Source Shall decide that the Sink is non-responsive, stop sending Source_Capabilities Messages and disable PD. A Sink Shall use the SinkWaitCapTimer to trigger the resending of Source_Capabilities Messages by a USB Power Delivery capable Source which has previously stopped sending Source_Capabilities Messages. Any Sink which is Attached and does not detect a Source_Capabilities Message, Shall issue Hard Reset Signaling when the SinkWaitCapTimer times out in order to reset the Source. Resetting the Source Shall also reset the CapsCounter and restart the sending of Source_Capabilities Messages. 6.7.5 Discover Identity Counter When sending Discover Identity Messages to a Cable Plug a Port Shall maintain a count of Messages sent (DiscoverIdentityCounter). No more than nDiscoverIdentityCount Discover Identity Messages Shall be sent by the Port without receiving a GoodCRC Message response. A VCONN Swap Shall reset the DiscoverIdentityCounter. 6.7.6 VDMBusyCounter When sending Responder BUSY responses to a Structured Vendor_Defined Message a UFP or Cable Plug Shall maintain a count of Messages sent (VDMBusyCounter). No more than nBusyCount Responder BUSY responses Shall be sent. The VDMBusyCounter Shall be reset on sending a non-BUSY response. Products wishing to meet [USB Type-C 2.4] requirements for Alternate Mode entry Should use an nBusyCount of 1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 267 6.7.7 Counter Values and Counters Table 6.70, "Counter Parameters" lists the counters used in this section and Table 6.71, "Counters" shows the corresponding parameters. Table 6.70 Counter Parameters Parameter Value Reference nBusyCount 5 Section 6.7.6 nCapsCount 50 Section 6.7.4 nDiscoverIdentityCount 20 Section 6.7.5 nHardResetCount 2 Section 6.7.3 nMessageIDCount 7 Section 6.7.1 nRetryCount 2 Section 6.7.2 Table 6.71 Counters Counter Max Reference CapsCounter nCapsCount Section 6.7.4 DiscoverIdentityCounter nDiscoverIdentityCount Section 6.7.5 HardResetCounter nHardResetCount Section 6.7.3 MessageIDCounter nMessageIDCount Section 6.7.1 RetryCounter nRetryCount Section 6.7.2 VDMBusyCounter nBusyCount Section 6.7.6
6.8 - Reset................................................................................................................................................. (Page 268)
Page 268 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.8 Reset Resets are a necessary response to protocol or other error conditions. USB Power Delivery defines four different types of reset:  Soft Reset, which resets protocol.  Data Reset which resets the USB Communications.  Hard Reset which resets both the power supplies and protocol  Cable Reset which resets the cable. 6.8.1 Soft Reset and Protocol Error A Soft_Reset Message is used to cause a Soft Reset of protocol communication when this has broken down in some way. It Shall Not have any impact on power supply operation but is used to correct a Protocol Error occurring during an Atomic Message Sequence (AMS). The Soft Reset May be triggered by either Port Partner in response to the Protocol Error. Protocol Errors are any unexpected Message during an AMS. If the first Message in an AMS has been passed to the Protocol Layer by the Policy Engine but has not yet been sent (i.e., a GoodCRC Message acknowledging the Message has not been received) when the Protocol Error occurs, the Policy Engine Shall Not issue a Soft Reset but Shall return to the PE_SNK_Ready or PE_SRC_Ready state and then process the incoming Message. If the incoming Message is an Unexpected Message received in the PE_SNK_Ready or PE_SRC_Ready state, the Policy Engine Shall issue a Soft Reset. If the Protocol Error occurs during an AMS this Shall lead to a Soft Reset in order to re-synchronize the Policy Engine state machines (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams") except when the voltage is transition when a Protocol Error Shall lead to a Hard Reset (see Section 6.6.11.4, "tProtErrHardReset" and Section 8.3.3.2, "Policy Engine Source Port State Diagram"). Details of AMS's can be found in Section 8.3.2.1.3, "Atomic Message Sequences". An Unrecognized Message or Unsupported Message received in the PE_SNK_Ready or PE_SRC_Ready states, Shall Not cause a Soft_Reset Message to be generated but instead a Not_Supported Message Shall be generated. A Soft_Reset Message Shall be sent regardless of the Rp value either SinkTxOK or SinkTxNG if it is the correct response in that state. Note: This means that a Soft_Reset Message can be sent during an AMS regardless of the Rp value either SinkTxOK or SinkTxNG when responding to a Protocol Error. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 269 Table 6.72, "Response to an incoming Message (except VDM)" and Table 6.73, "Response to an incoming VDM" summarize the responses that Shall be made to an incoming Message including VDMs. A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure resulting in a Soft Reset (see Section 6.6.9.1, "tSoftReset"). A Soft Reset Shall impact the USB Power Delivery layers in the following ways:  PHY Layer: Reset not required since the PHY Layer resets on each Packet transmission/reception.  Protocol Layer: Reset MessageIDCounter, RetryCounter and state machines. Table 6.72 Response to an incoming Message (except VDM) Recipient’s Power Role Recipient’s state Incoming Message Recognized Unrecognized Supported Unsupported Expected Unexpected Source PE_SRC_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (power not transitioning1) Process Message Soft_Reset Message2 During AMS (power transitioning1) Process Message Hard Reset Signaling Sink PE_SNK_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (not power transitioned) Process Message Soft_Reset Message2 During AMS (power transitioned) Process Message Hard Reset Signaling 1) “Power transitioning” means the Policy Engine is in PE_SRC_Transition_Supply State or PE_SNK_Transition_Sink State or PE_FRS_SNK_SRC_Start_AMS State. 2) The Soft_Reset Message Shall be sent using the SOP* of the incoming Message. 3) The Not_Supported Message Shall be sent using the SOP* of the incoming Message. Table 6.73 Response to an incoming VDM Recipient's Role Unstructured VDM Structured VDM Supported Unsupported Unrecognized Supported Unsupported Unrecognized DFP or UFP Defined by vendor Not_Supported Message Not_Supported Message See Section 6.13.5 Not_Supported Message NAK Command Cable Plug Defined by vendor Message Ignored Message Ignored See Section 6.13.5 Message Ignored NAK Command Page 270 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Policy Engine: Reset state dependent behavior by performing an Explicit Contract Negotiation.  Power supply: Shall Not change. Note: When in SPR Mode the Source sends a Source_Capabilities Message and when in EPR Mode the Source sends an EPR_Source_Capabilities Message. A Soft Reset is performed using an AMS (see Table 8.8, "AMS: Soft Reset"). Message numbers Shall be set to zero prior to sending the Soft_Reset/Accept Message since the issue might be with the counters. The sender of a Soft_Reset Message Shall reset its MessageIDCounter and RetryCounter, the receiver of the Message Shall reset its MessageIDCounter and RetryCounter before sending the Accept Message response. Any failure in the Soft Reset process will trigger a Hard Reset when SOP Packets are being used or Cable Reset, sent by the DFP only, for any other SOP* Packets; for example a GoodCRC Message is not received during the Soft Reset process (see Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). 6.8.2 Data Reset A Data_Reset Message is used by a Port to reset its USB data connection and to exit all Alternate Modes both with its Port Partner and in the Cable Plug(s).  The Data Reset process May be initiated by either Port Partner sending a Data_Reset Message. A Data Reset impacts USB Power Delivery in the following ways:  Shall Not change the Port Power Roles (Source/Sink) or Port Data Roles (DFP/UFP).  Shall Not change the existing Explicit Contract.  Shall cause all Active Modes to be exited.  Shall reset the cable by Power cycling VCONN.  The DFP Shall become the VCONN Source.  If the Data Reset process fails, then the Port Shall enter the ErrorRecovery State as defined in [USB Type-C 2.4]. See Section 6.3.14, "Data_Reset Message" for details of Data Reset operation. 6.8.3 Hard Reset Hard Resets are signaled by an ordered set as defined in Section 5.6.4, "Hard Reset". Both the sender and recipient Shall cause their power supplies to return to their default states (see Section 7.3.3.1, "Source Initiated Hard Reset" and Section 7.3.3.2, "Sink Initiated Hard Reset" for details of voltage transitions). In addition, their respective Protocol Layers Shall be reset as for the Soft Reset. This allows the Attached devices to be in a state where they can re-establish USB PD communication. Hard Reset is retried up to nHardResetCount times (see also Section 6.6.6, "NoResponseTimer" and Section 6.7.3, "Hard Reset Counter"). Note: Even though VBUS drops to vSafe0V during a Hard Reset a Sink will not see this as a disconnect since this is expected behavior. A Hard Reset Shall Not cause any change to either the Rp/Rd resistor being asserted. If there has been a Data Role Swap the Hard Reset Shall cause the Port Data Role to be changed back to DFP for a Port with the Rp resistor asserted and UFP for a Port with the Rd resistor asserted. When VCONN is supported (see [USB Type-C 2.4]) the Hard Reset Shall cause the Port with the Rp resistor asserted to supply VCONN and the Port with the Rd resistor asserted to turn off VCONN. In effect the Hard Reset will revert the Ports to their default state based on their CC line resistors. Removing and reapplying VCONN from the Cable Plugs also ensures that they re-establish their configuration as either SOP’ or SOP’’ based on the location of VCONN (see [USB Type-C 2.4]). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 271 If the Hard Reset is insufficient to clear the error condition, then the Port Shall use USB Type-C ErrorRecovery as defined in [USB Type-C 2.4]. A Sink Shall be able to send Hard Reset Signaling regardless of the value of Rp (see Section 5.7, "Collision Avoidance"). 6.8.3.1 Cable Plugs and Hard Reset Cable Plugs Shall Not generate Hard Reset Signaling but Shall monitor for Hard Reset Signaling between the Port Partners and Shall reset when this is detected (see Section 8.3.3.25.2.2, "Cable Plug Hard Reset State Diagram"). The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. 6.8.3.2 Modal Operation and Hard Reset A Hard Reset Shall cause EPR Mode and all Active Modes to be exited by both Port Partners and any Cable Plugs (see Section 6.4.4.3.4, "Enter Mode Command"). 6.8.4 Cable Reset Cable Resets are signaled by an ordered set as defined in Section 5.6.5, "Cable Reset". Both the sender and recipient of Cable Reset Signaling Shall reset their respective Protocol Layers. The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. The DFP must be supplying VCONN prior to a Cable Reset. If VCONN has been turned off the DFP Shall turn on VCONN prior to generating Cable Reset Signaling. If there has been a VCONN Swap and the UFP is currently supplying VCONN, the DFP Shall perform a VCONN Swap such that it is supplying VCONN prior to generating Cable Reset Signaling. Only a DFP Shall generate Cable Reset Signaling. A DFP Shall only generate Cable Reset Signaling within an Explicit Contract. A Cable Reset Shall cause all Active Modes in the Cable Plugs to be exited (see Section 6.4.4.3.4, "Enter Mode Command").
6.9 - Accept, Reject and Wait............................................................................................................ (Page 272)
Page 272 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.9 Accept, Reject and Wait The recipient of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message Shall respond by sending one of the following responses:  An Accept Message in response to a Valid request which can be serviced immediately (see Section 6.3.3, "Accept Message").  A Wait Message in response to a Valid request which cannot be serviced immediately but could be ser- viced at a later time (see Section 6.3.12, "Wait Message").  A Reject Message in response to an Invalid request or a request which is outside of the device's design Capabilities (see Section 6.3.4, "Reject Message").
6.10 - Collision Avoidance.................................................................................................................... (Page 273)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 273 6.10 Collision Avoidance To avoid Message collisions due to asynchronous Messaging sent from the Sink, the Source sets Rp to SinkTxOK to indicate to the Sink that it is OK to initiate an AMS. When the Source wishes to initiate an AMS, it sets Rp to SinkTxNG. When the Sink detects that Rp is set to SinkTxOK it May initiate an AMS. When the Sink detects that Rp is set to SinkTxNG it Shall Not initiate an AMS and Shall only send Messages that are part of an AMS the Source has initiated. Note: This restriction applies to SOP* AMS's i.e., for both Port to Port and Port to Cable Plug communications. If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. Note: A Sink can still send Hard Reset Signaling at any time.
6.11 - Message Discarding.................................................................................................................... (Page 274)
Page 274 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.11 Message Discarding On receiving a received Message on SOP, the Protocol Layer Shall Discard any pending SOP* Messages. A received Message on SOP’/SOP’’ Shall Not cause any pending SOP* Messages to be Discarded. It is assumed that Messages using SOP’/SOP’’ constitute a simple request/response AMS, with the Cable Plug providing the response so there is no reason for a pending SOP* Message to be Discarded. There can only be one AMS between the Port Partners, and these also take priority over Cable Plug communications so a Message received on SOP will always cause a Message pending on SOP* to be Discarded. Table 6.74, "Message Discarding" for details of the Messages that Shall/ Shall Not be Discarded. Table 6.74 Message Discarding Message pending transmission Message received Message to be Discarded SOP SOP Outgoing Message SOP SOP’/SOP’’ Incoming Message SOP’ SOP Outgoing Message SOP’ SOP’ Incoming Message SOP’ SOP’’ Incoming Message SOP’’ SOP Outgoing Message SOP’’ SOP’ Incoming Message SOP’’ SOP’’ Incoming Message
6.12 - State behavior............................................................................................................................... (Page 275)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 275 6.12 State behavior 6.12.1 Introduction to state diagrams used in Chapter 6 The state diagrams defined in Section 6.12, "State behavior" are Normative and Shall define the operation of the Power Delivery Protocol Layer. Note: These state diagrams are not intended to replace a well written and robust design. Figure 6.57, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state and in some states "Actions on exit" a list of actions carried out on exiting the state. Figure 6.57 Outline of States Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&." The inverse of a condition is shown with a "NOT" in front of the condition. In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams. Figure 6.57, "Outline of States" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the referenced state. Figure 6.58 References to states Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the state it is referenced. As soon as the state is exited then the timer is no longer active. Timeouts of the timers are listed as conditions on state transitions. Conditions listed on state transitions will come from one of three sources: <Name of State> Actions on entry: “List of actions to carry out on entering the state” Actions on exit: “List of actions to carry out on exiting the state” <Name of reference state> (<DFP | UFP>) Page 276 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Messages received from the PHY Layer.  Events triggered within the Protocol Layer e.g., timer timeouts  Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.) 6.12.2 State Operation The following section details Protocol Layer State Operation when sending and receiving SOP* Packets. For each SOP’ Communication being sent and received there Shall be separate Protocol Layer Transmission and Protocol Layer Reception and Hard Reset State Machine instances, with their own counter and timer instances. When Chunking is supported there Shall be separate Chunked Tx, Chunked Tx, and Chunked Message Router State Machine instances. Soft Reset Shall only apply to the State Machine instances it is targeted at based on the type of SOP* Packet used to send the Soft_Reset Message. The Hard Reset State Machine (including Cable Reset) Shall apply simultaneously to all Protocol Layer State Machine instances active in the DFP, UFP and Cable Plug (if present). 6.12.2.1 Protocol Layer Chunking 6.12.2.1.1 Architecture of Device Including Chunking Layer The Chunking component resides in the Protocol Layer between the Policy Engine and Protocol Tx/Rx. Figure 6.59, "Chunking architecture Showing Message and Control Flow" illustrates the relationship between components. The Chunking Layer comprises three related state machines:  Chunked Rx.  Chunked Tx.  Chunked Message Router. Note: The consequence of this architecture is that the Policy Engine deals entirely in Unchunked Messages. It will not receive (and might not respond to) a Message until all the related chunks have been collated. If a PD device or Cable Plug has no requirement to handle any Message requiring more than one Chunk of any Extended Message, it May omit the Chunking Layer. In this case it Shall implement the ChunkingNotSupportedTimer to ensure compatible operation with partners which support Chunking (see Section 6.6.18.1, "ChunkingNotSupportedTimer" and Section 8.3.3.6, "Not Supported Message State Diagrams"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 277 Figure 6.59 Chunking architecture Showing Message and Control Flow 6.12.2.1.1.1 Optional Abort Mechanism Long Chunked Messages bring with them the potential problem that they could prevent urgent Messages from being transmitted in a timely manner. An Optional Abort mechanism is provided to remedy this problem. The Abort Flag referred to in the diagrams below May be set and examined by the Policy Engine. The specific means are left to the implementer. 6.12.2.1.1.2 Aborting Sending a Long-Chunked Message A long-Chunked Message being sent May be aborted by setting the Optional Abort Flag. The Message Shall be considered aborted when the Abort Flag is again cleared by the Chunked Tx state machine. 6.12.2.1.1.3 Aborting Receiving a Long-Chunked Message If the Optional Abort mechanism has been implemented, any Message sent while a Chunked Message receive is in progress will result in an error report being received by the Policy Engine, to indicate that the Message request has been Discarded. If the Message was urgent the Policy Engine might set the Abort Flag, which will result in the incoming Chunked Message being aborted. The Abort Flag being cleared by the Chunked Rx state machine indicates that the urgent Message can now be sent. 6.12.2.1.2 Chunked Rx State Diagram Figure 6.60, "Chunked Rx State Diagram" shows the state behavior for the Chunked Rx State Machine. This recognizes whether Chunked received Messages are involved and deals with requesting chunks when they are. It also performs validity checks on all Messages related to Chunking. Policy Engine Protocol Layer Rx Protocol Layer Tx PHY Layer Rp Control or Detection Chunked Rx Chunked Tx Chunking Protocol Layer Hard Reset Chunked Message Router AMS Notification Page 278 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.60 Chunked Rx State Diagram 6.12.2.1.2.1 RCH_Wait_For_Message_From_Protocol_Layer State The Chunked Rx State Machine Shall enter the RCH_Wait_For_Message_From_Protocol_Layer state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine clears the Extended Rx Buffer and clears the Optional Abort Flag. In the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine waits until the Chunked Message Router passes up a received Message. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  A non-Extended Message is passed up from the Chunked Message Router.  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are not doing Chunking, and the Message has its Chunked bit set to 0b. The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are doing Chunking, and the Message has its Chunked bit set to 1b. 6.12.2.1.2.2 RCH_Pass_Up_Message State On entry to the RCH_Pass_Up_Message state the Chunked Rx state machine Shall pass the received Message to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Message has been passed. Transmission Error from Protocol Layer | Message Received from Protocol Layer Other Message Received from Protocol Layer | ChunkSenderResponseTimer timeout RCH_Pass_Up_Message Actions on entry: Pass Message to Policy Engine RCH_Wait_For_Message_From_Protocol_Layer Actions on entry: Clear Extended Rx Buffer Clear Abort Flag RCH_Report_Error Actions on entry: Report Error to Policy Engine. If a Message was received, pass it to the Policy Engine. RCH_Processing_ Extended_Message Actions on entry: If first chunk: set Chunk_Number_Expected = 0 and Num bytes received = 0 If expected Chunk Number: Append data to Extended_Message_Buffer; Increment Chunk_Number_Expected and adjust Num bytes received. RCH_Requesting_Chunk Actions on entry: Send notification SRT_Stop to SenderResponseTimer State Machine. Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. RCH_Waiting_Chunk Actions on entry: Start ChunkSenderResponseTimer3 Send notification SRT_Start to SenderResponseTimer State Machine.3 Start Message not Complete Message Transmitted received from Protocol Layer Unexpected Chunk Number Reported Chunked != Chunking1 Received Non-Extended Message | (Received Extended Message & (Chunking1 = 0 & Chunked = 0) ) Message is Complete (Num bytes received >= specified Data Size)2 Message Passed Chunk Response Received from Protocol Layer Received Extended Message & (Chunking1 = 1 & Chunked = 1) Any Message Received and not in state RCH_Waiting_Chunk or RCH_Wait_For_Message_From_ Protocol_Layer Abort Flag Set Soft Reset occured | Exit from Hard Reset 1) Chunking is an internal state that is set to 1 if the ‘Unchunked Extended Messages Supported’ bit in either Source Capabilities or Request is 0. It defaults to 1 and is set after the first exchange of Source Capabilities and Request. It is also set to 1 for SOP’ or SOP’’ communication. 2) Additional bytes received over specified Data Size will be because of padding in the last chunk. 3) This state is responsible for starting two timers of similar length. The implementor Should mitigate against more than one of these timers resulting in recovery action. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 279 6.12.2.1.2.3 RCH_Processing_Extended_Message State On entry to the RCH_Processing_Extended_Message state the Chunked Rx state machine Shall:  If this is the first chunk:  Set Chunk_Number_Expected = 0.  Set Num bytes received = 0.  If chunk contains the expected Chunk Number:  Append its data to the Extended_Message_Buffer.  Increment Chunk_Number_Expected.  Adjust Num bytes received. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  The Message is complete (i.e., Num bytes received >= specified Data Size. Note: The inequality allows for padding bytes in the last chunk, which are not actually part of the Extended Mes- sage). The Chunked Rx State Machine Shall transition to the RCH_Requesting_Chunk state when:  The Message is not yet complete. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  An unexpected Chunk Number is received. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Optional Abort Flag is set. 6.12.2.1.2.4 RCH_Requesting_Chunk State On entry to the RCH_Requesting_Chunk state the Chunked Rx state machine Shall:  Send notification SRT_Stop to SenderResponseTimer state machine (see Section 8.3.3.1.1, "SenderResponseTimer State Diagram").  Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. The Chunked Rx State Machine Shall transition to the RCH_Waiting_Chunk state when:  Message Transmitted is received from the Protocol Layer. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  Transmission Error is received from the Protocol Layer, or  A Message is received from the Protocol Layer. 6.12.2.1.2.5 RCH_Waiting_Chunk State On entry to the RCH_Waiting_Chunk state the Chunked Rx state machine Shall:  Start the ChunkSenderResponseTimer.  Send notification SRT_Start to SenderResponseTimer state machine (see SSection 8.3.3.1.1, "SenderResponseTimer State Diagram"). The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  A Chunk is received from the Protocol Layer. Page 280 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  A Message, other than a Chunk, is received from the Protocol Layer, or  The ChunkSenderResponseTimer expires. 6.12.2.1.2.6 RCH_Report_Error State The Chunked Rx State Machine Shall enter the RCH_Report_Error state:  When any Message is received and the Chunked Rx State Machine is not in one of the states RCH_Waiting_Chunk or RCH_Wait_For_Message_From_Protocol_Layer. On entry to the RCH_Report_Error state the Chunked Rx state machine Shall:  Report the error to the Policy Engine.  If the state was entered because a Message was received, this Message Shall be passed to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The error has been reported.  Any Message received was passed to the Policy Engine. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 281 6.12.2.1.3 Chunked Tx State Diagram Figure 6.61, "Chunked Tx State Diagram" shows the state behavior for the Chunked Tx State Machine. This recognizes whether Chunked transmitted Messages are involved and deals with sending chunks and waiting for chunk requests when they are. It also performs validity checks on all related Messages related to Chunking. Figure 6.61 Chunked Tx State Diagram 6.12.2.1.3.1 TCH_Wait_For_Message_Request_From_Policy_Engine State The Chunked Tx State Machine Shall enter the TCH_Wait_For_Message_Request_From_Policy_Engine state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx state machine clears the Optional Abort Flag. In the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx State Machine waits until the Policy Engine sends it a Message Request. The Chunked Tx State Machine Shall transition to the TCH_Pass_Down_Message state when:  A non-Extended Message Request is received from the Policy Engine, or  A Message Request is received from the Policy Engine and the link is not Chunking. TCH_Sending_ Chunked_Message Actions on entry: TCH_ Wait_ For_Message_Request_From_Policy_Engine Actions on entry: Clear Abort Flag TCH_Pass_Down_Message Actions on entry: Pass Message to Protocol Layer TCH_Construct_ Chunked_Message Actions on entry: Construct Message Chunk and pass to Protocol Layer TCH_Wait_For_ Transmision_Complete Actions on entry: TCH_Prepare_To_Send_ Chunked_Message Actions on entry: 'Chunk Number To Send' = 0 TCH_Wait_Chunk_Request Actions on entry: Increment Chunk Number to Send Start ChunkSenderRequestTimer TCH_Report_Error Actions on entry: Report Error to Policy Engine Soft Reset occured | Exit from Hard Reset Start Non-Extended Message Request | Not Chunking Message Passed Message Transmitted received from Protocol Layer TCH_Message_Sent Actions on entry: Inform Policy Engine of Message Sent Any Message Received and not in state TCH_Wait_Chunk_Request Chunking & Extended Message Request Chunk Number Set Chunk Passed Message Transmitted from Protocol Layer & Not Last Chunk TCH_Message_Received Actions on entry: Clear Extended Message Buffers Pass Message to Chunked Rx Message passed to Chunked Rx Message Transmitted received from Protocol Layer & Last Chunk (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Supported Abort Flag Set Informed Chunk Request Rcvd & Chunk Number = Chunk Number to Send Reported Other Message Received (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Not Supported Tx Error from Protocol Layer ChunkSenderRequestTimer timeout & Chunk Number = 0 (Chunk Request Rcvd & Chunk Number != Chunk Number to Send) | (ChunkSenderRequestTimer timeout & Chunk Number > 0) Transmission Error Page 282 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Prepare_To_Send_Chunked_Message state when:  An Extended Message Request is received from the Policy Engine, and the link is Chunking. The Chunked Tx State Machine Shall Discard the Message Request and remain in the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer, and the Optional Abort Flag has not been implemented. The Chunked Tx State Machine Shall Discard the Message Request and enter the TCH_Report_Error state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer and the Optional Abort Flag has been implemented. 6.12.2.1.3.2 TCH_Pass_Down_Message State On entry to the TCH_Pass_Down_Message state the Chunked Tx State Machine Shall pass the Message to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Transmision_Complete state when:  The Message has been passed to the Protocol Layer. 6.12.2.1.3.3 TCH_Wait_For_Transmision_Complete State The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted has been received from the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.4 TCH_Message_Sent State On entry to the TCH_Message_Sent state the Chunked Tx State Machine Shall:  Inform the Policy Engine that the Message has been sent. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Policy Engine has been informed. 6.12.2.1.3.5 TCH_Prepare_To_Send_Chunked_Message State On entry to the TCH_Prepare_To_Send_Chunked_Message state the Chunked Tx State Machine Shall:  Set 'Chunk Number To Send' to zero. The Chunked Tx State Machine Shall transition to the TCH_Construct_Chunked_Message state when:  ‘Chunk Number To Send' has been set to zero. 6.12.2.1.3.6 TCH_Construct_Chunked_Message State On entry to the TCH_Construct_Chunked_Message state the Chunked Tx State Machine Shall:  Construct a Message Chunk and pass it to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Sending_Chunked_Message state when:  The Message Chunk has been passed to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 283  The Optional Abort Flag is set. 6.12.2.1.3.7 TCH_Sending_Chunked_Message State The Chunked Tx State Machine Shall transition to the TCH_Wait_Chunk_Request state when:  Message Transmitted is received from Protocol Layer and this was not the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted is received from Protocol Layer and this was the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.8 TCH_Wait_Chunk_Request State On entry to the TCH_Wait_Chunk_Request state the Chunked Tx State Machine Shall:  Increment Chunk Number to Send.  Start ChunkSenderRequestTimer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  A Chunk Request has been received and the Chunk Number does not equal Chunk Number to Send or  ChunkSenderRequestTimer has expired and Chunk Number is greater than zero. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  ChunkSenderRequestTimer has expired and Chunk Number equals zero. Note: This is the mechanism which allows the remote Port Partner or Cable Plug to omit the Chunking Layer. The Policy Engine will receive a Message Sent signal if the remote Port Partner or Cable Plug is present (GoodCRC Message received) but does not send a Chunk Request. After this the remote Port Partner will send a Not_Supported Message, or the Cable Plug will Ignore the Chunked Message. The Chunked Tx State Machine Shall transition to the TCH_Message_Received state when:  Any other Message than Chunk Request is received. 6.12.2.1.3.9 TCH_Message_Received State The Chunked Tx State Machine Shall enter the TCH_Message_Received state:  When any Message is received, and the Chunked Tx State Machine is not in the TCH_Wait_Chunk_Request state. On entry to the TCH_Message_Received state the Chunked Tx State Machine Shall:  Clear the Extended Message Buffers.  Pass the received Message to Chunked Rx Engine. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The received Message has been passed to the Chunked Rx Engine. 6.12.2.1.3.10 TCH_Report_Error State On entry to the TCH_Report_Error state the Chunked Tx State Machine Shall:  Report the error to the Policy Engine. Page 284 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The error has been reported. 6.12.2.1.4 Chunked Message Router State Diagram Figure 6.62, "Chunked Message Router State Diagram" shows the state behavior for the Chunked Message Router. This determines to which state machine an incoming Message is routed to (Chunked Rx, Chunked Tx or direct to Policy Engine). Figure 6.62 Chunked Message Router State Diagram 6.12.2.1.4.1 RTR_Wait_for_Message_From_Protocol_Layer State In the RTR_Wait_for_Message_From_Protocol_Layer state the Chunked Message Router waits until the Protocol Layer sends it a received Message. The Chunked Message Router Shall transition to the RTR_Rx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is not doing Tx Chunks. The Chunked Message Router Shall transition to the RTR_Tx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is doing Tx Chunks. 6.12.2.1.4.2 RTR_Rx_Chunks State On entry to the RTR_Rx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Rx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. RTR_Wait_for_Message_From_Protocol_Layer Actions on entry: RTR_Rx_Chunks Actions on entry: Send message to Rx Chunk Machine RTR_Tx_Chunks Actions on entry: Send message to Tx Chunk Machine Message Received from Protocol Layer & Not Doing Tx Chunks1 Message Received from Protocol Layer & Doing Tx Chunks1 Sent Soft Reset occured | Exit from Hard Reset Start Sent 1) Doing Tx Chunks means that Chunked Tx State Machine is not in the TCH_Wait_For_Message_Request_From_Policy_Engine state. 2) Messages are taken to include notification about transmission success or otherwise of Messages. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 285 6.12.2.1.4.3 RTR_Tx_Chunks State On entry to the RTR_Tx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Tx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. Page 286 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2 Protocol Layer Message Transmission 6.12.2.2.1 Common Protocol Layer Message Transmission State Diagram Figure 6.63, "Common Protocol Layer Message Transmission State Diagram" shows the state behavior, common between the Source and the Sink, for the Protocol Layer when transmitting a Message. Figure 6.63 Common Protocol Layer Message Transmission State Diagram 6.12.2.2.1.1 PRL_Tx_PHY_Layer_Reset State The Protocol Layer Shall enter the PRL_Tx_PHY_Layer_Reset state:  At startup.  As a result of a Soft Reset request being received by the PHY Layer.  On exit from a Hard Reset. On entry to the PRL_Tx_PHY_Layer_Reset state the Protocol Layer Shall reset the PHY Layer (clear any outstanding Messages and enable communications). The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  When the PHY Layer reset is complete. 6.12.2.2.1.2 PRL_Tx_Wait_for_Message_Request State In the PRL_Tx_Wait_for_Message_Request state the Protocol Layer waits until the Policy Engine directs it to send a Message.  On entry to the PRL_Tx_Wait_for_Message_Request state the Protocol Layer Shall reset the RetryCounter. Message request received from Policy Engine (except Soft Reset) Message sent to PHY Layer CRCReceiveTimer Timeout | Message discarded bus Idle2 GoodCRC response received from PHY Layer MessageID mismatch (RetryCounter ” nRetryCount) & not Cable Plug & small Extended Message3 (RetryCounter > nRetryCount) | Cable Plug | large Extended Message3 Policy Engine informed of Transmission Error MessageID match Policy Engine informed message sent PRL_Tx_Check_RetryCounter Actions on entry: If DFP or UFP increment and check RetryCounter PRL_Tx_Transmission_Error Actions on entry: Increment MessageIDCounter Inform Policy Engine of Transmission Error PRL_Tx_Construct_Message Actions on entry: Construct message Pass message to PHY Layer PRL_Tx_Wait_for_PHY_response Actions on entry: Initialize and run CRCReceiveTimer1 PRL_Tx_Match_MessageID Actions on entry: Match MessageIDCounter and response MessageID Soft Reset Message request received from Policy Engine Layer Reset Complete PRL_Tx_Message_Sent Actions on entry: Increment MessageIDCounter Inform Policy Engine message sent PRL_Tx_Layer_Reset_for_Transmit Actions on entry: Reset MessageIDCounter. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. PRL_Tx_Wait_for_Message_Request Actions on entry: Reset RetryCounter PRL_Tx_Discard_Message Actions on entry: If any message is currently awaiting transmission Discard4 and increment MessageID Counter Discarding complete Protocol Layer message reception in PRL_Rx_Store_MessageID state | Fast Role Swap signal transmitted | Fast Role Swap signal detected Start Soft Reset Message from PHY Layer | Exit from Hard Reset PRL_Tx_PHY_Layer_Reset Actions on entry: Reset PHY Layer PHY Layer reset complete 1) The CRCReceiveTimer is only started after the PHY has sent the message. If the message is not sent due to a busy channel, then the CRCReceiveTimer will not be started (see Section 6.6.1 “CRCReceiveTimer”). 2) This indication is sent by the PHY Layer when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). The CRCReceiveTimer is not running in this case since no message has been sent. 3) A “small” Extended Message is either an Extended Message with Data Size ζMaxExtendedMsgLegacyLen bytes or an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has been Chunked. A “large” Extended Message is an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has not been Chunked. 4) See Section 6.11 “Message Discarding” for details of when Messages are Discarded . Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 287 The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message request is received from the Policy Engine which is not a Soft_Reset Message. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Message request is received from the Policy Engine which is a Soft_Reset Message. 6.12.2.2.1.3 PRL_Tx_Layer_Reset_for_Transmit State On entry to the PRL_Tx_Layer_Reset_for_Transmit state the Protocol Layer Shall reset the MessageIDCounter. The Protocol Layer Shall transition Protocol Layer Message reception to the PRL_Rx_Wait_for_PHY_Message state (see Section 6.12.2.3.1, "PRL_Rx_Wait_for_PHY_Message state") in order to reset the stored MessageID. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The layer reset actions in this state have been completed. 6.12.2.2.1.4 PRL_Tx_Construct_Message State On entry to the PRL_Tx_Construct_Message state the Protocol Layer Shall construct the Message requested by the Policy Engine, or resend a previously constructed Message, and then pass this Message to the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_PHY_Response state when:  The Message has been sent to the PHY Layer. 6.12.2.2.1.5 PRL_Tx_Wait_for_PHY_Response State On entry to the PRL_Tx_Wait_for_PHY_Response state, once the Message has been sent, the Protocol Layer Shall initialize and run the CRCReceiveTimer (see Section 6.6.1, "CRCReceiveTimer"). The Protocol Layer Shall transition to the PRL_Tx_Match_MessageID state when:  A GoodCRC Message response is received from the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The CRCReceiveTimer times out.  Or the PHY Layer indicates that a Message has been Discarded due to the channel being busy but the channel is now Idle (see Section 5.7, "Collision Avoidance"). 6.12.2.2.1.6 PRL_Tx_Match_MessageID State On entry to the PRL_Tx_Match_MessageID state the Protocol Layer Shall compare the MessageIDCounter and the MessageID of the received GoodCRC Message. The Protocol Layer Shall transition to the PRL_Tx_Message_Sent state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message match. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message do not match. 6.12.2.2.1.7 PRL_Tx_Message_Sent State On entry to the PRL_Tx_Message_Sent state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine that the Message has been sent. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed that the Message has been sent. Page 288 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.1.8 PRL_Tx_Check_RetryCounter State On entry to the PRL_Tx_Check_RetryCounter state the Protocol Layer in a DFP or UFP Shall increment the value of the RetryCounter and then check it in order to determine whether it is necessary to retry sending the Message. Note: Cable Plugs do not retry Messages and so do not use the RetryCounter. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state in order to retry Message sending when:  RetryCounter ≤ nRetryCount and  This is not a Cable Plug and  This is an Extended Message with Data Size ≤ MaxExtendedMsgLegacyLen or  This is an Extended Message that has been Chunked. The Protocol Layer Shall transition to the PRL_Tx_Transmission_Error state when:  RetryCounter > nRetryCount or  This is a Cable Plug, which does not retry.  This is an Extended Message with Data Size > MaxExtendedMsgLegacyLen that has not been Chunked. 6.12.2.2.1.9 PRL_Tx_Transmission_Error State On entry to the PRL_Tx_Transmission_Error state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine of the transmission error. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed of the transmission error. 6.12.2.2.1.10 PRL_Tx_Discard_Message State Protocol Layer Message transmission Shall enter the PRL_Tx_Discard_Message state whenever:  Protocol Layer Message reception receives an incoming Message or  The Fast Role Swap Request is being transmitted (see Section 5.8.5.6, "Fast Role Swap Transmission")  The Fast Role Swap Request is detected (see Section 5.8.6.3, "Fast Role Swap Detection"). On entry to the PRL_Tx_Discard_Message state, if there is a Message queued awaiting transmission, the Protocol Layer Shall Discard the Message according to the rules in Section 6.11, "Message Discarding" and increment the MessageIDCounter. The Protocol Layer Shall transition to the PRL_Tx_PHY_Layer_Reset state when:  Discarding is complete i.e., the Message queue is empty. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 289 6.12.2.2.2 Source Protocol Layer Message Transmission State Diagram Figure 6.64, "Source Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Source when transmitting a Message. Figure 6.64 Source Protocol Layer Message Transmission State Diagram PRL_Tx_Wait_for_Message_Request PRL_Tx_Src_Sink_Tx Actions on entry: Set Rp = SinkTxOk End of AMS notification received from Policy Engine Start of AMS notification received from Policy Engine PRL_Tx_Src_Pending Actions on entry: Start SinkTxTimer PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending & SinkTxTimer timeout Message pending (except Soft Reset) & SinkTxTimer timeout Rp set PRL_Tx_Src_Source_Tx Actions on entry: Set Rp = SinkTxNG Message request from Policy Engine Page 290 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.2.1 PRL_Tx_Src_Sink_Tx State In the PRL_Tx_Src_Sink_Tx state the Source sets Rp to SinkTxOK allowing the Sink to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Sink_Tx state when:  A notification is received from the Policy Engine that the end of an AMS has been reached. On entry to the PRL_Tx_Src_Sink_Tx state the Protocol Layer Shall request the PHY Layer to Rp to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  Rp has been set. 6.12.2.2.2.2 PRL_Tx_Src_Source_Tx State In the PRL_Tx_Src_Source_Tx state the Source sets Rp to SinkTxNG allowing the Source to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Source_Tx state when:  A notification is received from the Policy Engine that an AMS will be starting. On entry to the PRL_Tx_Src_Source_Tx state the Protocol Layer Shall set Rp to SinkTxNG. The Protocol Layer Shall transition to the PRL_Tx_Src_Pending state when:  A Message request is received from the Policy Engine. 6.12.2.2.2.3 PRL_Tx_Src_Pending State In the PRL_Tx_Src_Pending state the Protocol Layer has a Message buffered ready for transmission. On entry to the PRL_Tx_Src_Pending state the SinkTxTimer Shall be initialized and run. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The pending Message request from the Policy Engine is not a Soft_Reset Message and  The SinkTxTimer times out. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  The pending Message request from the Policy Engine is a Soft_Reset Message and  The SinkTxTimer times out. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 291 6.12.2.2.3 Sink Protocol Layer Message Transmission State Diagram Figure 6.65, "Sink Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Sink when transmitting a Message. Figure 6.65 Sink Protocol Layer Message Transmission State Diagram 6.12.2.2.3.1 PRL_Tx_Snk_Start_of_AMS State In the PRL_Tx_Snk_Start_of_AMS state the Protocol Layer waits for the first Message in a Sink initiated AMS. The Protocol Layer in a Sink Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Snk_Start_of_AMS state when:  A notification is received from the Policy Engine that the next Message the Sink will send is the start of an AMS. The Protocol Layer Shall transition to the PRL_Tx_Snk_Pending state when:  A Message request is received from the Policy Engine. PRL_Tx_Wait_for_Message_Request First Message in AMS notification received from Policy Engine PRL_Tx_Snk_Pending Actions on entry: PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending Message pending (except Soft Reset) & Rp = SinkTxOk PRL_Tx_Snk_Start_of_AMS Actions on entry: Message Request from Policy Engine Page 292 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.3.2 PRL_Tx_Snk_Pending State In the PRL_Tx_Snk_Pending state the Protocol Layer has the first Message in a Sink initiated AMS ready to send and is waiting for Rp to transition to SinkTxOK before sending the Message. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message is Pending that is not a Soft_Reset Message and  Rp is set to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Soft_Reset Message is pending. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 293 6.12.2.3 Protocol Layer Message Reception Figure 6.66, "Protocol layer Message reception" shows the state behavior for the Protocol Layer when receiving a Message. Figure 6.66 Protocol layer Message reception 6.12.2.3.1 PRL_Rx_Wait_for_PHY_Message state The Protocol Layer Shall enter the PRL_Rx_Wait_for_PHY_Message state:  At startup.  As a result of a Soft Reset request from the Policy Engine.  On exit from a Hard Reset. In the PRL_Rx_Wait_for_PHY_Message state the Protocol Layer waits until the PHY Layer passes up a received Message. The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC state when:  A Message is passed up from the PHY Layer. The Protocol Layer Shall transition to the PRL_Rx_Layer_Reset_for_Receive state when:  A Soft_Reset Message is received from the PHY Layer. Message received from PHY (except Soft Reset) Message passed to Policy Engine (GoodCRC sent | Message discarded bus Idle1) MessageID <> stored MessageID | no stored value MessageID = stored MessageID Start PRL_Rx_Send_GoodCRC Actions on entry: Send GoodCRC message to PHY PRL_Rx_Store_MessageID Actions on entry: Protocol Layer message transmission transitions to PRL_Tx_Discard_Message state2. Store new MessageID Pass message to Policy Engine3 PRL_Rx_Wait_for_PHY_message Actions on entry: PRL_Rx_Check_MessageID Actions on entry: If there is a stored value compare MessageID with stored value. Soft Reset Message received from PHY Soft Reset complete PRL_Rx_Layer_Reset_for_Receive Actions on entry: Reset MessageIDCounter and clear stored MessageID value Protocol Layer message transmission transitions to PRL_Tx_PHY_Layer_Reset state. Soft Reset request from Policy Engine | Exit from Hard Reset Message discarded bus Idle1 1) This indication is sent by the PHY when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). Two alternate allowable transitions are shown. 2) In the case of a Ping message being received, in order to maintain robust communications in the presence of collisions, the outgoing message Should Not be Discarded. 3) See Section 6.11 “Message Discarding” for details of when Messages are discarded. Page 294 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.3.2 PRL_Rx_Layer_Reset_for_Receive state On entry to the PRL_Rx_Layer_Reset_for_Receive state the Protocol Layer Shall reset the MessageIDCounter and clear the stored MessageID. The Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Wait_for_Message_Request state (see Section 6.12.2.2.1.2, "PRL_Tx_Wait_for_Message_Request State"). The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC State when:  The Soft Reset actions in this state have been completed. 6.12.2.3.3 PRL_Rx_Send_GoodCRC state On entry to the PRL_Rx_Send_GoodCRC state the Protocol Layer Shall construct a GoodCRC Message and request the PHY Layer to transmit it. The Protocol Layer Shall transition to the PRL_Rx_Check_MessageID state when:  The GoodCRC Message has been passed to the PHY Layer. When the PHY Layer indicates that a Message has been Discarded due to CC being busy but CC is now Idle (see Section 5.7, "Collision Avoidance"), the Protocol Layer Shall either:  Transition to the PRL_Rx_Check_MessageID state or  Transition to the PRL_Rx_Wait_for_PHY_Message state. 6.12.2.3.4 PRL_Rx_Check_MessageID state On entry to the PRL_Rx_Check_MessageID state the Protocol Layer Shall compare the MessageID of the received Message with its stored value if a value has previously been stored. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The MessageID of the received Message equals the stored MessageID value since this is a Message retry which Shall be Discarded. The Protocol Layer Shall transition to the PRL_Rx_Store_MessageID state when:  The MessageID of the received Message does not equal the stored MessageID value since this is a new Message or  This is the first received Message and no MessageID value is currently stored. 6.12.2.3.5 PRL_Rx_Store_MessageID state On entry to the PRL_Rx_Store_MessageID state the Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Discard_Message state, replace the stored value of MessageID with the value of MessageID in the received Message and pass the Message up to the Policy Engine. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The Message has been passed up to the Policy Engine. 6.12.2.4 Hard Reset operation Figure 6.57, "Outline of States" shows the state behavior for the Protocol Layer when receiving a Hard Reset or Cable Reset request from the Policy Engine or Hard Reset Signaling or Cable Reset Signaling from the PHY Layer (see also Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 295 Figure 6.67 Hard/Cable Reset 6.12.2.4.1 PRL_HR_Reset_Layer state The PRL_HR_Reset_Layer State defines the mode of operation of both the Protocol Layer transmission and reception state machines during a Hard Reset or Cable Reset. During Hard Reset no USB Power Delivery Protocol Messages are sent or received; only Hard Reset Signaling is present after which the communication channel is assumed to have been disabled by the PHY Layer until completion of the Hard Reset. During Cable Reset no USB Power Delivery Protocol Messages are sent to or received by the Cable Plug but other USB Power Delivery communication May continue. The Protocol Layer Shall enter the PRL_HR_Reset_Layer state from any other state when:  A Hard Reset Request is received from the Policy Engine or  Hard Reset Signaling is received from the PHY Layer or Hard Reset request received from Policy Engine2 | Cable Reset request received from Policy Engine4 | Hard Reset signalling received By PHY Layer | Cable Reset signalling received By PHY Layer3 PHY Hard Reset request sent | PHY Cable Reset request sent Hard Reset complete from Policy Engine | Cable Reset complete from Policy Engine Physical Layer informed PRL_HR_Request_Hard_Reset Actions on entry: Request PHY to perform a Hard Reset or Cable Reset PRL_HR_Reset_Layer Actions on entry: Reset MessageIDCounter. Protocol Layer message transmission transitions to PRL_Tx_Wait_For_Message_Request state. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. Protocol Layer reset complete & (Hard Reset was Initiated by Policy Engine | Cable Reset was Initiated by Policy Engine) Policy Engine informed Protocol Layer reset complete & (Hard Reset was initiated by Port Partner | Cable Reset received by Cable Plug) PRL_HR_Indicate_Hard_Reset Actions on entry: Inform the Policy Engine of the Hard Reset or Cable Reset Exit from Hard Reset Policy Engine informed PRL_HR_PHY_Hard_Reset_Requested Actions on entry: Inform Policy Engine Hard Reset or Cable Reset request has been sent PRL_HR_Wait_For_PE_Hard_Reset_Complete Actions on entry: Wait for Hard Reset or Cable Reset complete indication from Policy Engine. PRL_HR_PE_Hard_Reset_Complete Actions on entry: Inform Physical Layer Hard Reset or Cable Reset is complete PRL_HR_Wait_For_PHY_Hard_Reset_Complete Actions on entry: Start HardResetCompleteTimer Wait for Hard Reset or Cable Reset complete indication from PHY Hard Reset complete from PHY | Cable Reset complete from PHY | HardResetCompleteTimer timeout1 1) If the HardResetCompleteTimer timeout occurs this means that the PHY is still waiting to send the Hard Reset due to a non-idle channel. This condition will be cleared once the PE Hard Reset is completed. 2) Cable Plugs do not generate Hard Reset signaling but are required to monitor for Hard Reset signaling between the Port Partners and respond by resetting. 3) Cable Reset signaling is only recognized by a Cable Plug. 4) Cable Reset signaling cannot be generated by Cable Plugs. Page 296 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Cable Reset Request is received from the Policy Engine or  Cable Reset Signaling is received from the PHY Layer. On entry to the PRL_HR_Reset_Layer state the Protocol Layer Shall reset the MessageIDCounter. It Shall also reset the states of the Protocol Layer transmission and reception state machines to their starting points. The Protocol Layer transmission state machine Shall transition to the PRL_Tx_Wait_for_Message_Request state. The Protocol Layer reception state machine Shall transition to the PRL_Rx_Wait_for_PHY_Message state. The Protocol Layer Shall transition to the PRL_HR_Request_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has originated from the Policy Engine or  The Cable Reset request has originated from the Policy Engine. The Protocol Layer Shall transition to the PRL_HR_Indicate_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has been passed up from the PHY Layer or  A Cable Reset request has been passed up from the PHY Layer (Cable Plug only). 6.12.2.4.2 PRL_HR_Indicate_Hard_Reset state On entry to the PRL_HR_Indicate_Hard_Reset state the Protocol Layer Shall indicate to the Policy Engine that either Hard Reset Signaling or Cable Reset Signaling has been received. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when:  The indication to the Policy Engine has been sent. 6.12.2.4.3 PRL_HR_Request_Hard_Reset state On entry to the PRL_HR_Request_Hard_Reset state the Protocol Layer Shall request the PHY Layer to send either Hard Reset Signaling or Cable Reset Signaling. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state when:  The PHY Layer Hard Reset Signaling request has been sent or  The PHY Layer Cable Reset Signaling request has been sent. 6.12.2.4.4 PRL_HR_Wait_for_PHY_Hard_Reset_Complete state In the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state the Protocol Layer Shall start the HardResetCompleteTimer and wait for the PHY Layer to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PHY_Hard_Reset_Requested state when:  A Hard Reset complete indication is received from the PHY Layer or  A Cable Reset complete indication is received from the PHY Layer or  The HardResetCompleteTimer times out. 6.12.2.4.5 PRL_HR_PHY_Hard_Reset_Requested state On entry to the PRL_HR_PHY_Hard_Reset_Requested state the Protocol Layer Shall inform the Policy Engine that the PHY Layer has been requested to perform a Hard Reset or Cable Reset. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 297  The Indication to the Policy Engine has been sent. 6.12.2.4.6 PRL_HR_Wait_for_PE_Hard_Reset_Complete state In the PRL_HR_Wait_for_PE_Hard_Reset_Complete state the Protocol Layer Shall wait for the Policy Engine to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PE_Hard_Reset_Complete state when:  A Hard Reset complete indication is received from the Policy Engine or  A Cable Reset complete indication is received from the Policy Engine. 6.12.2.4.7 PRL_HR_PE_Hard_Reset_Complete On entry to the PRL_HR_PE_Hard_Reset_Complete state the Protocol Layer Shall inform the PHY Layer that the Hard Reset or Cable Reset is complete. The Protocol Layer Shall exit from the Hard Reset and return to normal operation when:  The PHY Layer has been informed that the Hard Reset is complete so that it will re-enable the communications channel. If Hard Reset Signaling is still pending due to a non-Idle channel this Shall be cleared and not sent or  The PHY Layer has been informed that the Cable Reset is complete. Page 298 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.3 List of Protocol Layer States Table 6.75, "Protocol Layer States" lists the states used by the various state machines. Table 6.75 Protocol Layer States State Name Section Protocol Layer Message Transmission Common Protocol Layer Message Transmission PRL_Tx_PHY_Layer_Reset Section 6.12.2.2.1.1 PRL_Tx_Wait_for_Message_Request Section 6.12.2.2.1.2 PRL_Tx_Layer_Reset_for_Transmit Section 6.12.2.2.1.3 PRL_Tx_Construct_Message Section 6.12.2.2.1.4 PRL_Tx_Wait_for_PHY_Response Section 6.12.2.2.1.5 PRL_Tx_Match_MessageID Section 6.12.2.2.1.6 PRL_Tx_Message_Sent Section 6.12.2.2.1.7 PRL_Tx_Check_RetryCounter Section 6.12.2.2.1.8 PRL_Tx_Transmission_Error Section 6.12.2.2.1.9 PRL_Tx_Discard_Message Section 6.12.2.2.1.10 Source Protocol Layer Message Transmission PRL_Tx_Src_Sink_Tx Section 6.12.2.2.2.1 PRL_Tx_Src_Source_Tx Section 6.12.2.2.2.2 PRL_Tx_Src_Pending Section 6.12.2.2.2.3 Sink Protocol Layer Message Transmission PRL_Tx_Snk_Start_of_AMS Section 6.12.2.2.3.1 PRL_Tx_Snk_Pending Section 6.12.2.2.3.2 Protocol Layer Message Reception PRL_Rx_Wait_for_PHY_Message Section 6.12.2.3.1 PRL_Rx_Layer_Reset_for_Receive Section 6.12.2.3.2 PRL_Rx_Send_GoodCRC Section 6.12.2.3.3 PRL_Rx_Check_MessageID Section 6.12.2.3.4 PRL_Rx_Store_MessageID Section 6.12.2.3.5 Hard Reset Operation PRL_HR_Reset_Layer Section 6.12.2.4.1 PRL_HR_Indicate_Hard_Reset Section 6.12.2.4.2 PRL_HR_Request_Hard_Reset Section 6.12.2.4.3 PRL_HR_Wait_for_PHY_Hard_Reset_Complete Section 6.12.2.4.4 PRL_HR_PHY_Hard_Reset_Requested Section 6.12.2.4.5 PRL_HR_Wait_for_PE_Hard_Reset_Complete Section 6.12.2.4.6 PRL_HR_PE_Hard_Reset_Complete Section 6.12.2.4.7 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 299 Chunking Chunked Rx RCH_Wait_For_Message_From_Protocol_Layer Section 6.12.2.2.1.1 RCH_Pass_Up_Message Section 6.12.2.2.1.1 RCH_Processing_Extended_Message Section 6.12.2.2.1.1 RCH_Requesting_Chunk Section 6.12.2.2.1.1 RCH_Waiting_Chunk Section 6.12.2.2.1.1 RCH_Report_Error Section 6.12.2.2.1.1 Chunked Tx TCH_Wait_For_Message_Request_From_Policy_Engine Section 6.12.2.1.3.1 TCH_Pass_Down_Message Section 6.12.2.1.3.2 TCH_Wait_For_Transmision_Complete Section 6.12.2.1.3.3 TCH_Message_Sent Section 6.12.2.1.3.4 TCH_Prepare_To_Send_Chunked_Message Section 6.12.2.1.3.5 TCH_Construct_Chunked_Message Section 6.12.2.1.3.6 TCH_Sending_Chunked_Message Section 6.12.2.1.3.7 TCH_Wait_Chunk_Request Section 6.12.2.1.3.8 TCH_Message_Received Section 6.12.2.1.3.9 TCH_Report_Error Section 6.12.2.1.3.10 Chunked Message Router RTR_Wait_for_Message_From_Protocol_Layer Section 6.12.2.1.4.1 RTR_Rx_Chunks Section 6.12.2.1.4.2 RTR_Tx_Chunks Section 6.12.2.1.4.3 Table 6.75 Protocol Layer States (Continued) State Name Section
6.13 - Message Applicability............................................................................................................... (Page 300)
Page 300 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13 Message Applicability The following tables outline the Messages supported by a given Port, depending on its capability. When a Message is supported the feature and the AMS implied by the Message Shall also be supported. The abbreviations in Table 6.76, "Message Applicability Abbreviations" are used in this section to denote the level of support required. For the case of Conditional Normative a note has been added to indicate the condition. "CN/" notation is used to indicate the level of support when the condition is not present. "R/" and "O/" notation is used to indicate the response when the Recommended or Optional Message is not supported. Note: Where NS/R/NK is indicated for Received Messages this Shall apply to the PE_CBL_Ready, PE_SNK_Ready or PE_SRC_Ready states only since unexpected Messages received during an AMS are Pro- tocol Errors (see Section 6.8.1, "Soft Reset and Protocol Error"). This section covers Control Message and Data Message support for Sources, Sink and Cable Plugs. It also covers VDM Command support for DFPs, UFPs and Cable Plugs. Table 6.76 Message Applicability Abbreviations Abbreviation Meaning Description N Normative Shall be supported by this Port/Cable Plug. CN Conditional Normative Shall supported by a given Port/Cable Plug based on features. R Recommended Should be supported by this Port/Cable Plug. O Optional May be supported by this Port/Cable Plug. NS Not Supported Shall result in a Not_Supported Message response by this Port/Cable Plug when received. I Ignore Shall be Ignored by this Port/Cable Plug when received. NK NAK This Port/Cable Plug Shall return Responder NAK to this Command when received. NA Not allowed Shall Not be transmitted by this Port/Cable Plug. DR Don’t Recognize There Shall be no response at all (i.e., not even a GoodCRC Message) from this Port/Cable Plug when received. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 301 6.13.1 Applicability of Control Messages Table 6.77, "Applicability of Control Messages" details Control Messages that Shall/Should/Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.77 Applicability of Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 Transmitted Message Accept N N N N Data_Reset CN10/R CN10/R NA NA DR_Swap O O N NA NA FR_Swap NA NA R NA NA Get_Country_Codes CN7/NA CN7/NA NA NA Get_PPS_Status NA CN6 NA NA Get_Sink_Cap R NA N NA NA Get_Sink_Cap_Extended R NA R NA NA Get_Source_Cap NA R N NA NA Get_Source_Cap_Extended NA R R NA NA Get_Source_Info NA R R NA NA Get_Revision R R NA NA Get_Status R R NA NA GoodCRC N N N N GotoMin (Deprecated) NA NA NA NA Not_Supported N N NA NA Ping (Deprecated) NA NA NA NA PR_Swap NA NA N NA NA PS_RDY N CN1/NA N NA NA Reject N O O O CN10/NA NA Soft_Reset N N NA NA VCONN_Swap R R NA NA Wait O NA O O NA NA 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Page 302 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Received Message Accept N N N N I I Data_Reset CN10/R CN10/R I I DR_Swap O/NS O/NS N I I FR_Swap NS NS CN4/NS I I Get_Country_Codes CN7/NS CN7/NS I I Get_PPS_Status CN6/NS NS I I Get_Sink_Cap NS N N I I Get_Sink_Cap_Extended NS N N I I Get_Source_Cap N NS N I I Get_Source_Cap_Extended CN2/NS NS CN2/NS I I Get_Source_Info CN11 NS N I I Get_Revision N N O/I O/I Get_Status CN3/NS CN3/NS CN3/NS CN8/I I GoodCRC N N N N GotoMin (Deprecated) NS NS I I Not_Supported N N CN8/I I Ping (Deprecated) NS NS/I I I PR_Swap NS NS N I I PS_RDY CN1/NS N N I I Reject CN5/NS N N N I I Soft_Reset N N N N VCONN_Swap CN1/ NS CN1/ NS I I Wait CN5/NS N N N I I Table 6.77 Applicability of Control Messages (Continued) Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 303 6.13.2 Applicability of Data Messages Table 6.78, "Applicability of Data Messages" details Data Messages (except for VDM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.78 Applicability of Data Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 Transmitted Message Source_Capabilities N NA N NA NA NA Request NA N NA NA NA Get_Country_Info CN5/O CN5/O NA NA NA BIST N1 N1 NA NA NA Sink_Capabilities NA N N NA NA NA Battery_Status CN2 CN2 NA NA NA Alert CN11/R CN11/R NA NA NA Enter_USB CN7/O CN7/O NA NA NA EPR_Request NA CN9 NA NA NA EPR_Mode CN9 CN9 NA NA NA Source_Info CN10 NA N NA NA NA Revision N N CN12/O/I NA O Received Message Source_Capabilities NS N N I I I Request N NS I I I Get_Country_Info CN5/NS CN5/NS I I I BIST N1 N1 N1 N1 N1 Sink_Capabilities CN4 NS CN4 I I I Battery_Status CN3/NS CN3/NS I I I Alert R/NS R/NS I I I Enter_USB CN7/O CN7/O CN8/I CN8/I I 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Page 304 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 EPR_Request CN9 NA I I I EPR_Mode CN9 CN9 I I I Source_Info NA N N I I I Revision N N I I I Table 6.78 Applicability of Data Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 305 6.13.3 Applicability of Extended Messages Table 6.79, "Applicability of Extended Messages" details Extended Messages (except for VDEM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual- Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.79 Applicability of Extended Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 Transmitted Message Battery_Capabilities CN1/NA CN1/NA NA NA NA Country_Codes CN10/NA CN10/NA NA NA NA Country_Info CN10/NA CN10/NA NA NA NA EPR_Source_Capabilities CN14/NA NA CN14/NA NA NA NA EPR_Sink_Capabilities NA CN14/NA CN14/NA NA NA NA Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NA CN7/NA NA NA NA Firmware_Update_Response CN7/NA CN7/NA CN7/NA O NA Get_Battery_Cap R R NA NA NA Get_Battery_Status R R NA NA NA Get_Manufacturer_Info R R NA NA NA Manufacturer_Info R R R NA NA PPS_Status CN8/NA NA NA NA NA Security_Request CN6/NA CN6/NA NA NA NA Security_Response CN6/NA CN6/NA CN6/NA NA NA Sink_Capabilities_Extended NA N N NA NA NA Source_Capabilities_Extended R NA R NA NA NA 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 306 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Status CN15/R CN15/R CN15/R CN12/NA CN12/NA NA Vendor_Defined_Extended O O O O O Received Message Battery_Capabilities CN4/NS CN4/NS I I I Country_Codes CN10/NS CN10/NS I I I Country_Info CN10/NS CN10/NS I I I EPR_Source_Capabilities NS CN14/NS CN14/NS I I I EPR_Sink_Capabilities CN14/NS NS CN14/NS I I I Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NS CN7/NS CN7/I O I Firmware_Update_Response CN7/NS CN7/NS I I I Get_Battery_Cap CN1/NS CN1/NS I I I Get_Battery_Status CN1/NS CN1/NS I I I Get_Manufacturer_Info R/NS R/NS R/I I I Manufacturer_Info CN5/NS CN5/NS I I I PPS_Status NS CN9/NS I I I Security_Request CN6/NS CN6/NS CN6/I I I Security_Response CN6/NS CN6/NS I I I Sink_Capabilities_Extended CN11/NS NS CN11/NS I I I Source_Capabilities_Extended NS CN2/NS CN2/NS I I I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 307 Status CN33/NS CN3/NS I I I Vendor_Defined_Extended O/NS O/NS O/I O/I O/I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 308 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.4 Applicability of Extended Control Messages Table 6.80, "Applicability of Extended Control Messages" details Extended Control Messages that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.80 Applicability of Extended Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD2 Transmitted Message EPR_Get_Source_Cap NA CN1 CN1 NA NA EPR_Get_Sink_Cap CN1 NA CN1 NA NA EPR_KeepAlive NA CN1 NA NA EPR_KeepAlive_Ack CN1 NA NA NA Received Message EPR_Get_Source_Cap CN1 NS CN1 I I EPR_Get_Sink_Cap NS CN1 CN1 I I EPR_KeepAlive CN1 NS I I EPR_KeepAlive_Ack NS CN1 I I 1) Shall be supported by products that support EPR Mode. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 309 6.13.5 Applicability of Structured VDM Commands Table 6.81, "Applicability of Structured VDM Commands" details Structured VDM Commands that Shall/Should/ Shall Not be transmitted and received by a DFP, UFP, Cable Plug or VPD. If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. Table 6.81 Applicability of Structured VDM Commands Command Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD4 Transmitted Command Request Discover Identity CN1,6/R R2 NA NA NA Discover SVIDs CN1/O O NA NA NA Discover Modes CN1/O O NA NA NA Enter Mode CN1/NA NA NA NA NA Exit Mode CN1/NA NA NA NA NA Attention O O NA NA NA Received Command Request/Transmitted Command Response Discover Identity CN5,6/R/ NK3 CN1,6/R/ NK3 N I N Discover SVIDs O/NK3 CN1/NK3 CN1/NK I NK Discover Modes O/NK3 CN1/NK3 CN1/NK I NK Enter Mode NK3 CN1/NK3 CN1/NK O NK Exit Mode NK3 CN1/NK3 CN1/NK O NK Attention O/I3 O/I3 I I I 1) Shall be supported when Modal Operation is supported. 2) May be transmitted by a UFP/Source during discovery (see Section 6.4.4.3.1, "Discover Identity" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 3) If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. 4) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT- VPD Shall only take place when not Connected to a Charger. 5) Shall be supported by products with more than one DFP. 6) Shall be supported by products that support [USB4]. Page 310 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.6 Applicability of Reset Signaling Table 6.82, "Applicability of Reset Signaling" details the Reset that Shall/Should/ Shall Not be transmitted and received by a DFP/UFP or Cable Plug. 6.13.7 Applicability of Fast Role Swap Request Table 6.83, "Applicability of Fast Role Swap Request" details the Fast Role Swap Request that Shall/Should/ Shall Not be transmitted and received by a Source or Sink. Table 6.82 Applicability of Reset Signaling Reset Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD2 Transmitted Message/Signaling Soft_Reset N N NA NA NA Hard Reset N N NA NA NA Cable Reset CN1 NA NA NA NA Received Message/Signaling Soft_Reset N N N N N Hard Reset N N N N N Cable Reset DR DR N N N 1) Shall be supported when transmission of SOP’ Packets are supported, and the Port can supply VCONN. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Table 6.83 Applicability of Fast Role Swap Request Command Type Source Sink Dual-Role Power Transmitted Message/Signaling Fast Role Swap NA NA R Received Message/Signaling Fast Role Swap NA NA R
6.14 - Value Parameters........................................................................................................................ (Page 311)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 311 6.14 Value Parameters Table 6.84, "Value Parameters" contains value parameters used in this section. Table 6.84 Value Parameters Parameter Description Value Unit Reference MaxExtendedMsgLen Maximum length of an Extended Message as expressed in the Data Size field. 260 Byte Section 6.2.1.2 MaxExtendedMsgChunkLen Maximum length of an Extended Message Chunk. 26 Byte Section 6.2.1.2 MaxExtendedMsgLegacyLen Maximum length of an Extended Message that can be sent without Chunking. 26 Byte Section 6.2.1.2
7 - Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 312)
Page 312 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7 Power Supply 7.1 Source Requirements 7.1.1 Behavioral Aspects A PDUSB Source exhibits the following behaviors:  Shall supply [USB Type-C 2.4] USB Type-C® current to VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS voltage transitions as bound by undershoot, overshoot and transition time requirements. 7.1.2 Source Bulk Capacitance The Source bulk capacitance Shall Not be placed between the transceiver isolation impedance and the USB receptacle. The Source bulk capacitance consists of C1 and C2 as shown in Figure 7.1, "Placement of Source Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect might also be part of the circuit implemented by the Source to limit its VBUS Output Voltage Limit (OVL) as described in Section 7.1.7.5, "Output Voltage Limit". Though a Source Shall limit its output voltage, a Sink Shall implement Sink OVP as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. If the power supply is shared across multiple ports, the bulk capacitance is defined as cSrcBulkShared. If the power supply is dedicated to a single Port, the minimum bulk capacitance is defined as cSrcBulk. The Source bulk capacitance is allowed to change for a newly Negotiated power level. The capacitance change Shall occur before the Source is ready to operate at the new power level. During a Power Role Swap, the Initial Source Shall transition to Swap Standby before operating as the New Sink. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.1 Placement of Source Bulk Capacitance 7.1.3 Types of Sources Consistent with the Power Data Objects discussed in Section 6.4.1, "Capabilities Message", the power supply types that are available as Sources in a USB Power Delivery System are:  The Fixed Supply PDO exposes well-regulated fixed voltage power supplies. Sources Shall support at least one Fixed Supply capable of supplying vSafe5V. The output voltage of a Fixed Supply Shall remain C2 Ohmic Interconnect GND SHIELD VBUS ... Data Lines GND SHIELD VBUS ... Data Lines SOURCE CABLE C1 Power Supply Source Bulk Capacitance OVL
7.1 - Source Requirements................................................................................................................ (Page 312)
Page 312 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7 Power Supply 7.1 Source Requirements 7.1.1 Behavioral Aspects A PDUSB Source exhibits the following behaviors:  Shall supply [USB Type-C 2.4] USB Type-C® current to VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS voltage transitions as bound by undershoot, overshoot and transition time requirements. 7.1.2 Source Bulk Capacitance The Source bulk capacitance Shall Not be placed between the transceiver isolation impedance and the USB receptacle. The Source bulk capacitance consists of C1 and C2 as shown in Figure 7.1, "Placement of Source Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect might also be part of the circuit implemented by the Source to limit its VBUS Output Voltage Limit (OVL) as described in Section 7.1.7.5, "Output Voltage Limit". Though a Source Shall limit its output voltage, a Sink Shall implement Sink OVP as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. If the power supply is shared across multiple ports, the bulk capacitance is defined as cSrcBulkShared. If the power supply is dedicated to a single Port, the minimum bulk capacitance is defined as cSrcBulk. The Source bulk capacitance is allowed to change for a newly Negotiated power level. The capacitance change Shall occur before the Source is ready to operate at the new power level. During a Power Role Swap, the Initial Source Shall transition to Swap Standby before operating as the New Sink. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.1 Placement of Source Bulk Capacitance 7.1.3 Types of Sources Consistent with the Power Data Objects discussed in Section 6.4.1, "Capabilities Message", the power supply types that are available as Sources in a USB Power Delivery System are:  The Fixed Supply PDO exposes well-regulated fixed voltage power supplies. Sources Shall support at least one Fixed Supply capable of supplying vSafe5V. The output voltage of a Fixed Supply Shall remain C2 Ohmic Interconnect GND SHIELD VBUS ... Data Lines GND SHIELD VBUS ... Data Lines SOURCE CABLE C1 Power Supply Source Bulk Capacitance OVL Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 313 within the range defined by the relative tolerance vSrcNew and the absolute band vSrcValid as listed in Table 7.23, "Source Electrical Parameters" and described in Section 7.1.8, "Output Voltage Tolerance and Range".  The Variable Supply (non-Battery) PDO exposes less well-regulated Sources. The output voltage of a Variable Supply (non-Battery) Shall remain within the absolute maximum output voltage and the absolute minimum output voltage exposed in the Variable Supply PDO.  The Battery Supply PDO exposes Batteries than can be connected directly as a Source to VBUS. The output voltage of a Battery Supply Shall remain within the absolute maximum output voltage and the absolute minimum output exposed in the Battery Supply PDO.  The Programmable Power Supply (PPS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the Programmable Power Supply Shall remain within a range defined by the relative tolerance vPpsNew and the absolute band vPpsValid.  The Adjustable Voltage Supply (AVS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the AVS Shall remain within a range defined by the relative tolerance vAvsNew and the absolute band vAvsValid. 7.1.4 Source Transitions 7.1.4.1 Fixed Supply 7.1.4.1.1 Fixed Supply Positive Voltage Transitions The Source Shall transition VBUS from the starting voltage to the higher new voltage in a controlled manner. The Negotiated new voltage (e.g., 5V, 9V, 15V, …) defines the nominal value for vSrcNew. During the positive transition the Source Should be able to supply the Sink Standby current and the transient current to charge the total bulk capacitance on VBUS. The slew rate of the positive transition Shall Not exceed vSrcSlewPos. The transitioning Source output voltage Shall settle within vSrcNew by tSrcSettle. The Source Shall be able to supply the Negotiated power level at the new voltage by tSrcReady. The positive voltage transition Shall remain above vSrcValid min of the previous Explicit Contract and below vSrcValid max of the new Explicit Contract (Figure 7.2, "Transition Envelope for Positive Voltage Transitions"). The voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.2, "Transition Envelope for Positive Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.2 Transition Envelope for Positive Voltage Transitions At the start of the positive voltage transition the VBUS voltage level Shall Not droop vSrcValid min below either vSrcNew (i.e., if the starting VBUS voltage level is not vSafe5V) or vSafe5V as applicable. Starting voltage vSrcNew(typ) t0 vSrcSlewPos tSrcSettle vSrcValid(max) Upper bound of valid Source range vSrcNew(max) vSrcNew(min) tSrcReady Lower bound of valid Source range § § vSrcValid(min) beyond min/max limits of starting voltage Page 314 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewPos limit. 7.1.4.1.2 Fixed Supply Negative Voltage Transitions Negative voltage transitions are defined as shown in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" and are specified in a similar manner to positive voltage transitions. Figure 7.3, "Transition Envelope for Negative Voltage Transitions" does not apply to vSafe0V transitions. The slew rate of the negative transition Shall Not exceed vSrcSlewNeg. The negative voltage transition Shall remain below vSrcValid max of the previous Explicit Contract and above vSrcValid min of the new Explicit Contract, as shown in FFigure 7.3, "Transition Envelope for Negative Voltage Transitions". The transitioning Source output voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.3 Transition Envelope for Negative Voltage Transitions If the newly Negotiated voltage is vSafe5V, then the vSrcValid limits Shall determine the transition window and the transitioning Source Shall settle within the vSafe5V limits by tSrcSettle. Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewNeg limit. 7.1.4.2 SPR Programmable Power Supply (PPS) 7.1.4.2.1 SPR Programmable Power Supply Voltage Transitions The Programmable Power Supply (PPS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the Programmable RDO defines the nominal value of the PPS output voltage after completing a voltage change and Shall settle within the limits defined by vPpsNew by tPpsSrcTransSmall for steps smaller than or equal to vPpsSmallStep, or else, within the limits defined by vPpsNew by tPpsSrcTransLarge, but only in case the Programmable Power Supply is not in CL mode. Any overshoot beyond vPpsNew Shall Not exceed vPpsValid at any time. Any undershoot beyond vPpsNew Shall Not exceed vPpsValid for currents not resulting in CL mode. The PPS output voltage May change in a step-wise or linear manner and the slew rate of either type of change Shall Not exceed vPpsSlewPos for voltage increases or vPpsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the PPS output voltage is defined as vPpsStep. A PPS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level. All PPS voltage increases Shall Starting voltage Lower bound of valid Source range Upper bound of valid Source range t0 tSrcSettle tSrcReady vSrcNew(typ) vSrcValid(min) vSrcNew(max) vSrcNew(min) § vSrcSlewNeg § vSrcValid(max) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 315 result in a voltage that is greater than or equal to the previous PPS output voltage. Likewise, all PPS voltage decreases Shall result in a voltage that is less than or equal to the previous PPS output voltage. Since a Sink can draw current up to the Negotiated APDO current level in case of a voltage step, the voltage might not increase to the requested level due to the power supply operating in CL mode. Likewise, since a Sink can have a Battery connected to VBUS, the voltage might not decrease to the requested level due to the Battery voltage being higher than the output voltage set point the Source is transitioning to. Were the Source to rely on checking the voltage on VBUS, in either case, to determine when its power supply is ready a PS_RDY Message would never be sent. When the PPS voltage steps up or down, a PS_RDY Message Shall be sent within:  tPpsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vPpsSmallStep.  tPpsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vPpsSmallStep provided that either the voltage on VBUS has reached vPpsNew or the power supply is in CL mode. When vPpsNew is lower than the Battery voltage, or the Source's primary power is cut off the Sink Shall immediately disconnect its Battery from VBUS. In these situations, the output current could reverse polarity and the Sink is not allowed to source current (see Section 7.2.1, "Behavioral Aspects" and Section 7.2.9, "Robust Sink Operation"). Figure 7.4, "PPS Positive Voltage Transitions" and Figure 7.5, "PPS Negative Voltage Transitions" below show the output voltage behavior of a Programmable Power Supply in response to positive and negative voltage change requests. The parameters vPpsMinVoltage and vPpsMaxVoltage define the lower and upper limits of the PPS range respectively (see Table 10.11, "SPR Programmable Power Supply Voltage Ranges" for required ranges). vPpsMinVoltage corresponds to the Minimum Voltage field in the PPS APDO and vPpsMaxVoltage corresponds to Maximum Voltage field in the PPS APDO. If the Sink negotiates for a new PPS APDO, then the transition between the two PPS APDOs Shall occur as described in Section 7.3.1, "Transitions caused by a Request Message". Figure 7.4 PPS Positive Voltage Transitions vPpsMinVoltage V(2) = 1 + vPpsMinVoltage vPpsMinVoltage V(1) § § Programmable Power Supply Output Range § vPpsSlewPos V(3) = 1+n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § vPpsSlewPos vPpsSlewPos § § § § vPpsValid vPpsNew § § vPpsValid vPpsValid vPpsNew § § vPpsValid Nominal V(2) Nominal V(3) vPpsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) Page 316 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.5 PPS Negative Voltage Transitions Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vPpsSlewNeg and vPpsSlewPos limits. See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage and current DNL step adjustments. 7.1.4.2.2 SPR Programmable Power Supply Current Limit The Programmable Power Supply operating in SPR PPS Mode Shall limit its output current to the Operating Current field value in the RDO when the Sink attempts to draw more current than the Operating Current field value level. The programming step size for the Operating Current is iPpsCLStep. All programming changes of the Operating Current Shall settle to the new Operating Current field value within tPpsCLProgramSettle. The SPR PPS Operating Current regulation accuracy during Current Limit is defined as iPpsCLNew. The minimum programmable Current Limit level is iPpsCLMin. A Source that supports SPR PPS Mode Shall support Current Limit programmability between iPpsCLMin and the Maximum Current value in the SPR PPS APDO. A Source which receives a request for current below iPpsCLMin Should reject the request. A Source that accepts a request for current below iPpsCLMin Shall set its current limit at 1A. The response of an SPR PPS to a load change depends on the Operating mode of the SPR PPS and the magnitude of the load change. These dependencies lead to one of four possible responses of an SPR PPS to any load change. They are differentiated by the value of the PPS Status OMF before and after the load change:  If the PPS Status OMF is cleared both before and after the load change, the SPR PPS responds solely by maintaining the output voltage. The SPR PPS output voltage Shall remain within vPpsValid range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsTransient. The Operating Mode Flag Shall remain cleared during the load change response of the SPR PPS.  If the PPS Status OMF is cleared before the load change and set after the load change, the SPR PPS responds by reducing its output voltage to limit the SPR PPS output current. The SPR PPS output current Shall stay within the iPpsCVCLTransient range once it reaches the iPpsCVCLTransient range. The SPR vPpsMinVoltage V(c) = 1 + vPpsMinVoltage vPpsMinVoltage V(d) § § Programmable Power Supply Output Range § V(b) = 1 + n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § § § § vPpsValid vPpsNew § § vPpsValid Nominal V(c) Nominal V(b) vPpsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vPpsValid vPpsNew § § vPpsValid § vPpsSlewNeg vPpsSlewNeg vPpsSlewNeg Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 317 PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCVCLTransient. The Operating Mode Flag Shall be set when the SPR PPS load change response settles.  If the PPS Status OMF is set both before and after the load change, the SPR PPS responds by adjusting its output voltage to maintain the output current. The SPR PPS output current Shall stay within the iPpsCLTransient range. The SPR PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCLSettle. The Operating Mode Flag Shall remain set during the load change response of the SPR PPS.  If the PPS Status OMF is set before the load change and cleared after the load change, the PPS responds to the load change by increasing its output voltage to vPpsNew and then maintaining it. The SPR PPS output voltage Shall stay within the vPpsCLCVTransient range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsCLCVTransient. The Operating Mode Flag Shall be cleared when the PPS load change response settles. The SPR PPS Source Shall maintain its output voltage at the value requested in the PPS RDO for all static and dynamic load conditions except when in Current Limit operation. In response to any static or dynamic load condition during Current Limit operation that causes the SPR PPS output voltage to drop below vPpsShutdown the Source May send Hard Reset Signaling and Shall discharge VBUS to vSafe0V then resumes USB Default Operation at vSafe5V. When the Sink attempts to draw more current than the Operating Current in the RDO, the Source Shall limit its output current. The current available from the Source during Current Limit mode Shall meet iPpsCLNew. The Sink May Not reduce its Operating Current request in the RDO when the PPS Status OMF is set. Current limiting Shall be performed by the SPR PPS Source. Sinks that rely on PPS Current Limiting Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The Source Shall Not shutdown or otherwise disrupt the available output power while in Current Limit mode unless another protection mechanism as outlined in Section 7.1.7, "Robust Source Operation" is engaged to protect the Source from damage. An SPR PPS Source that is operating in Current Limit Shall Not change its set-point in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The relationship between SPR PPS programmable output voltage and SPR PPS programmable Current Limit Shall be as shown in Figure 7.6, "SPR PPS Programmable Voltage and Current Limit". The transition between the Constant Voltage mode and the Current Limit mode occurs between points a and b. The PPS Status OMF Shall be set or cleared within this region. In Current Limit mode when the load resistance changes, the output current of the Source Shall stay within iPpsCLNew. The proper behavior is represented by point c. Page 318 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.6 SPR PPS Programmable Voltage and Current Limit 7.1.4.2.3 SPR PPS Constant Power Mode In Constant Power mode (when the PPS Power Limited bit is set) the Source May supply power that exceeds the Source's PDP Rating. Sinks May limit their Operating Current request in the RDO and Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The tolerances along the Constant Power Curve Shall Not extend into the Guaranteed Capability Area of Figure 7.7, "SPR PPS Constant Power". Current Voltage PPS APDO Min Voltage (max) PPS APDO Max Voltage iPpsCLMin PPS APDO Max Current vPpsNew PPS RDO Operating Current PPS RDO Output Voltage Programmable Voltage Only Region Programmable Voltage & Programmable Current Limit Region Valid Current Limit Response Invalid Current Limit Response iPpsCLNew a Current Limit Flag set Current Limit Flag cleared b c c c Source Disconnect Region vPpsShutdown (min) Point a represents entry into the transition region between Constant Voltage mode and Current Limit mode. Point b represents exit from the transition region between Constant Voltage mode and Current Limit mode. Point c represents the exit from the iPpsCLNew region as the voltage drops below the PPS APDO Min Voltage. The Source May disconnect at any point inside the tolerance range of the minimum voltage defined in the PPS APDO. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 319 Figure 7.7 SPR PPS Constant Power Current Voltage Nominal limits as pr. the APDO Guaranteed operating capability as pr. the APDO Tolerance area for actual voltages (only static tolerances are shown) vPpsNew PDP constant power curve Max APDO Voltage Capabilities when the Power Limited bit is set The figure shows only the steady state after the transition vPpsNew 0A 0V iPpsCLNew (X = PPS APDO Max Current, Y = Prog Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • Prog Voltage = 9V • PPS APDO Max Current = 3 A Coordinate = (3, 9) vPpsNew Min APDO Voltage vPpsNew iPpsCLMin(1A) Min Current Limit PPS APDO Max Current Valid Current Limit Range (X = PDP/PPS APDO Max Current, Y = PPS APDO Max Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • PPS APDO Max Voltage = 11 V Coordinate = (2.45, 11) Page 320 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3 Adjustable Voltage Supply (AVS) 7.1.4.3.1 Adjustable Voltage Supply Voltage Transitions The Adjustable Voltage Supply (AVS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the AVS RDO defines the nominal value of the AVS output voltage after completing a voltage change and Shall settle within the limits defined by vAvsNew by tAvsSrcTransSmall for steps smaller than or equal to vAvsSmallStep, or else, within the limits defined by vAvsNew by tAvsSrcTransLarge for steps larger than vAvsSmallStep. Any overshoot beyond vAvsNew Shall Not exceed vAvsValid at any time. Any undershoot beyond vAvsNew Shall Not exceed vAvsValid at any time. The AVS output voltage May change in a stepwise or linear manner and the slew rate of either type of change Shall Not exceed vAvsSlewPos for voltage increases or vAvsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the AVS output voltage is defined as vAvsStep. An AVS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level if the change of output voltage is less than or equal to vAvsSmallStep relative to vAvsNew. All AVS voltage increases Shall result in a voltage that is greater than or equal to the previous AVS output voltage. Likewise, all AVS voltage decreases Shall result in a voltage that is less than or equal to the previous AVS output voltage. Any time the Source enters the AVS range of operation that voltage transition is considered a voltage step larger than vAvsSmallStep. When the AVS voltage steps up or down, a PS_RDY Message Shall be sent within:  tAvsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vAvsSmallStep.  tAvsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vAvsSmallStep provided the voltage on VBUS has reached vAvsNew. Figure 7.8, "AVS Positive Voltage Transitions" and Figure 7.9, "AVS Negative Voltage Transitions" below show the output voltage behavior of an AVS in response to positive and negative voltage change requests. The parameters vAvsMinVoltage and vAvsMaxVoltage define the lower and upper limits of the AVS range respectively:  For SPR AVS Sources there are two possible voltage ranges where the vAvsMinVoltage is always 9V and vAvsMaxVoltage is either 15V or 20V depending on the Source's PDP. See Table 10.9, "SPR Adjustable Voltage Supply (AVS) Voltage Ranges".  For EPR AVS Sources vAvsMinVoltage corresponds to Minimum Voltage field (always 15V) in the EPR AVS APDO and vAvsMaxVoltage corresponds to Maximum Voltage field in the EPR AVS APDO. See Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" for required ranges. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 321 Figure 7.8 AVS Positive Voltage Transitions Figure 7.9 AVS Negative Voltage Transitions See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage DNL step adjustments. vAvsMinVoltage V(2) = 1 + vAvsMinVoltage vAvsMinVoltage V(1) § § Adjustable Voltage Supply Output Range § vAvsSlewPos V(3) = 1+n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § vAvsSlewPos vAvsSlewPos § § § § vAvsValid vAvsNew § § vAvsValid vAvsValid vAvsNew § § vAvsValid Nominal V(2) Nominal V(3) vAvsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) vAvsMinVoltage V(c) = 1 + vAvsMinVoltage vAvsMinVoltage V(d) § § Adjustable Voltage Supply Output Range § V(b) = 1 + n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § § § § vAvsValid vAvsNew § § vAvsValid Nominal V(c) Nominal V(b) vAvsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vAvsValid vAvsNew § § vAvsValid § vAvsSlewNeg vAvsSlewNeg vAvsSlewNeg Page 322 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3.2 Adjustable Voltage Supply Current The AVS Shall maintain its output voltage at the value requested in the AVS RDO for all static and dynamic load conditions that do not exceed the Operating Current in the RDO. Unlike the SPR PPS programmable current, the AVS programmable power May range from zero to the PDP. The maximum operating current:  For SPR Sources, the maximum operating current is defined in the SPR Source_Capabilities Message Maximum Current 15V/Maximum Current 20V fields.  For EPR Sources, the maximum operating current has to be calculated as the lower of the PDP field value/Output Voltage or 5A whichever is lower. See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" 7.1.5 Response to Hard Resets Hard Reset Signaling indicates a communication failure has occurred and the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall drive VBUS to vSafe0V as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". The USB connection May reset during a Hard Reset since the VBUS voltage will be less than vSafe5V for an extended period of time. After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform to the VCONN timing as specified in [USB Type-C 2.4]. A Sink that enters Hard Reset can have cSnkBulkPd present until VBUS drops below vSafe0V. The Source Shall take this into consideration. Device operation during and after a Hard Reset is defined as follows:  Self-powered devices Should Not disconnect from USB during a Hard Reset (see Section 9.1.2, "Mapping to USB Device States").  Self-powered devices operating at more than vSafe5V May Not maintain full functionality after a Hard Reset.  Bus powered devices will disconnect from USB during a Hard Reset due to the loss of their power source. When a Hard Reset occurs the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall start to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. The Source Shall meet both tSafe5V and tSafe0V relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 323 Figure 7.10 Source VBUS and VCONN Response to Hard Reset VCONN will meet tVCONNDischarge relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset" due to the discharge circuitry in the Cable Plug. VCONN Shall meet tVCONNOn relative to VBUS reaching vSafe5V. Note: tVCONNOn and tVCONNDischarge are defined in [USB Type-C 2.4]. 7.1.6 Changing the Output Power Capability Some USB Power Delivery Negotiations will require the Source to adjust its output power capability without changing the output voltage. In this case the Source Shall be able to supply a higher or lower load current within tSrcReady. 7.1.7 Robust Source Operation 7.1.7.1 Output Over Current Protection Sources Shall implement over current protection to prevent damage from output current that exceeds the current handling capability of the Source. The definition of current handling capability is left to the discretion of the Source implementation and Shall take into consideration the current handling capability of the connector contacts. If the over current protection implementation does not use a Hard Reset or Error Recovery, it Shall Not interfere with the Negotiated VBUS current level. After three consecutive over current events Source Shall go to ErrorRecovery. Sources Should attempt to send Hard Reset Signaling when over current protection engages followed by an Alert Message indicating an OCP event once an Explicit Contract has been established. The over current protection response May engage at either the Port or system level. Systems or ports that have engaged over current protection Should attempt to resume USB Default Operation after determining that the cause of over current is no longer present and May latch off to protect the Port or system. The definition of how to detect if the cause of over current is still present is left to the discretion of the Source implementation. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over current event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over current protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over current. During the over current response and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. Old voltage 0V vSafe0V(max) vSrcNeg(max) t0 tSafe5V tSafe0V tSrcTurnOn vSafe5V(max), VCONN(max) § vVconnDischarge tVconnDischarge tVconnOn tSrcRecover Page 324 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.7.2 Over Temperature Protection Sources Shall implement Over Temperature Protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Source. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Source implementation. In order to avoid reaching an OTP event, Sources May proactively reduce the available power being offered to the Sink, even though these offers might be lower than the Source would be expected to offer during normal thermal operating conditions. Prior to reducing power, the Source Should generate Alert Message indicating an Operating Condition Change and set the Temperature Status bit in the SOP Status Message to Warning (10b). Sources Should attempt to send Hard Reset Signaling when OTP engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The OTP response May engage at either the Port or system level. Systems or ports that have engaged OTP Should attempt to resume USB Default Operation and May latch off to protect the Port or system. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over temperature event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. During the OTP and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. 7.1.7.3 vSafe5V Externally Applied to Ports Supplying vSafe5V Safe operation mandates that Power Delivery Sources Shall be tolerant of vSafe5V being present on VBUS when simultaneously applying power to VBUS. Normal USB PD communication Shall be supported when this vSafe5V to vSafe5V connection exists. 7.1.7.4 Detach A USB Detach is detected electrically using CC detection on the USB Type-C connector. When the Source is Detached the Source Shall transition to vSafe0V by tSafe0V relative to when the Detach event occurred. During the transition to vSafe0V the VBUS voltage Shall be below vSafe5V max by tSafe5V relative to when the Detach event occurred and Shall Not exceed vSafe5V max after this time. Sources operating in EPR Mode need to avoid creating large differential voltages at the connector. See Appendix H in the [USB Type-C 2.4] specification for background information. To achieve this, Sources operating in EPR Mode, upon detecting a disconnect, Shall stop sourcing current and minimize VBUS capacitance. There May continue to be current sourced from the Source bulk capacitance, but that Should also be minimized by disconnecting as much of the Source bulk capacitance as possible. For example, the Source can stop sourcing from the Power Supply and the C1 portion of the Source bulk capacitance in Figure 7.1, "Placement of Source Bulk Capacitance" by disabling the Ohmic Interconnect switch. The Source Should detect the disconnect, stop sourcing current, and minimize the VBUS capacitance as quickly as practical. If this is done after the CC contacts disconnect and before the VBUS contacts disconnect there is less risk of large differential voltages at the connector. Note: A USB-PD transmission by the Source during a disconnect event will delay disconnect detection by the Source. 7.1.7.5 Output Voltage Limit The output voltage of Sources Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid or vAvsNew, vAvsValid as determined by the Negotiated VBUS value. Sources Shall meet applicable safety and regulatory requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 325 7.1.8 Output Voltage Tolerance and Range After a voltage transition is complete (i.e., after tSrcReady) and during static load conditions the Source output voltage Shall remain within the vSrcNew or vSafe5V limits as applicable. The ranges defined by vSrcNew and vSafe5V account for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e., after tSrcReady) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vSrcValid. The amount of time the Source output voltage can be in the band between either vSrcNew or vSafe5V and vSrcValid Shall Not exceed tSrcTransient. Refer to Table 7.23, "Source Electrical Parameters" for the output voltage tolerance specifications. Figure 7.11, "Application of vSrcNew and vSrcValid limits after tSrcReady" illustrates the application of vSrcNew and vSrcValid after the voltage transition is complete. The vSrcNew and vSrcValid limits Shall Not apply to VBUS during the VBUS discharge and switchover that occurs during a Fast Role Swap as described in Section 7.1.13, "Fast Role Swap". Figure 7.11 Application of vSrcNew and vSrcValid limits after tSrcReady The Source output voltage Shall be measured at the connector receptacle. The stability of the Source Shall be tested in 25% load step increments from minimum load to maximum load and also from maximum load to minimum load. The transient behavior of the load current is defined in Section 7.2.6, "Transient Load Behavior". The time between each step Shall be sufficient to allow for the output voltage to settle between load steps. In some systems it might be necessary to design the Source to compensate for the voltage drop between the output stage of the power supply electronics and the receptacle contact. The determination of whether compensation is necessary is left to the discretion of the Source implementation. 7.1.8.1 AVS/PPS Output Voltage Ripple The AVS/PPS output voltage ripple is expected to exceed the magnitude of one or more LSB as show in the Figure 7.12, "Expected AVS/PPS Ripple Relative to an LSB". Sink Load I1 vSrcNew(typ) tSrcReady iLoadStepRate vSrcValid(max) vSrcValid(min) vSrcNew(max) vSrcNew(min) tSrcTransient window у tSrcTransient windows у у iLoadReleaseRate Sink Load I2 Page 326 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.12 Expected AVS/PPS Ripple Relative to an LSB 7.1.8.2 AVS/PPS DNL Errors and Output Voltage/Current Tolerance The PPS voltage and current discrete LSB steps have a DNL tolerance as shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode" below. In absolute terms the step size of the LSB for both voltage and current is defined by vPpsStep/vAvsStep for voltage and iPpsCLStep for current. Several examples of Valid LSB steps are shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode":  The upper end of the DNL error (+1 LSB) shows the case where one step is effectively skipped.  The lower end of the DNL error (-1 LSB) shows the case where the voltage or current set-point remained the same. The ideal scenario for the DNL error (=0) matches the typical step size for the voltage or current. The intent of DNL is to guarantee that changes to the voltage/current have the correct directionality, and that the maximum step size is clearly defined. Note: The Source Should avoid scenarios where multiple consecutive steps have errors close to the Maximum and Minimum DNL. time voltage +1 LSB +1 LSB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 327 Figure 7.13 Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode 7.1.8.3 Programmable Power Supply Output Voltage Tolerance and Range After a voltage transition of a Programmable Power Supply is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vPpsNew limits. The range defined by vPpsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vPpsValid. The amount of time the Source output voltage can be in the band between vPpsNew and vPpsValid Shall Not exceed tPpsTransient. 7.1.8.4 Adjustable Voltage Supply Output Voltage tolerance and Range After a voltage transition of an AVS is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vAvsNew limits. The range defined by vAvsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vAvsValid. The amount of time the Source output voltage can be in the band between vAvsNew and vAvsValid Shall Not exceed tAvsTransient. Code Voltage, Current 1 LSB DNL < 0 LSB Max DNL = 1 LSB vPpsNew,vAvsNew, iPpsNew (max) vPpsNew,vAvsNew, iPpsNew (min) vPpsNew,vAvsNew, iPpsNew DNL = -1 LSB Page 328 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.9 Charging and Discharging the Bulk Capacitance on VBUS The Source Shall charge and discharge the bulk capacitance on VBUS whenever the Source voltage is Negotiated to a different value. The charging or discharging occurs during the voltage transition and Shall Not interfere with the Source's ability to meet tSrcReady. 7.1.10 Swap Standby for Sources Sources and Sinks of a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Source after the Source power supply has discharged the bulk capacitance on VBUS to vSafe0V as part of the Power Role Swap transition. While in Swap Standby:  The Source Shall Not drive VBUS that is therefore expected to remain at vSafe0V.  Any discharge circuitry that was used to achieve vSafe0V Shall be removed from VBUS.  The Dual-Role Power Port Shall be configured as a Sink.  The USB connection Shall Not reset even though vSafe5V is no longer present on VBUS (see Section 9.1.2, "Mapping to USB Device States"). The PS_RDY Message associated with the Source being in Swap Standby Shall be sent after the VBUS drive is removed. The time for the Source to transition to Swap Standby Shall Not exceed tSrcSwapStdby. Upon entering Swap Standby, the Source has relinquished its Power Role as Source and is ready to become the New Sink. The transition time from Swap Standby to being the New Sink Shall be no more than tNewSnk. The New Sink May start using power after the new Source sends the PS_RDY Message. 7.1.11 Source Peak Current Operation A Source that has the Fixed Supply PDO or AVS APDO Peak Current bits set to 01b, 10b and 11b Shall be designed to support one of the overload Capabilities defined in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability" respectively. The overload conditions are bound in magnitude, duration and duty cycle as listed in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability". Sources are not required to support continuous overload operation. When overload conditions occur, the Source is allowed the range of vSrcPeak (instead of vSrcNew) relative to the nominal value (see Figure 7.14, "Source Peak Current Overload"). When the overload capability is exceeded, the Source is expected take whatever action is necessary to prevent electrical or thermal damage to the Source. The Source May send a new Source_Capabilities Message with the Fixed Supply PDO or AVS APDO Peak Current bits set to 00b to prohibit overload operation even if an overload capability was previously Negotiated with the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 329 Figure 7.14 Source Peak Current Overload 7.1.12 Source Capabilities Extended Parameters Implementers can choose to make available certain characteristics of a PDUSB Source as a set of Static and/or dynamic parameters to improve interoperability between external power sources and portable computing devices. The complete list of reportable Static parameters is described in full in Section 6.5.1, "Source_Capabilities_Extended Message" and listed in Figure 6.37, "Source_Capabilities_Extended Message". The subset of parameters listed below directly represent Source Capabilities and are described in the rest of this section.  Voltage Regulation.  Holdup Time.  Compliance.  Peak Current.  Source Inputs.  Batteries. 7.1.12.1 Voltage Regulation Field The power consumption of a device can change dynamically. The ability of the Source to regulate its voltage output might be important if the device is sensitive to fluctuations in voltage. The Voltage Regulation bit field is used to convey information about the Sources output regulation and tolerance to various load steps. 7.1.12.1.1 Load Step Slew Rate The default load step slew rate is established at 150mA/µs. A Source Shall meet the following requirements under the load step reported in the Source_Capabilities_Extended Message:  The Source Shall maintain VBUS regulation within the vSrcValid range.  The noise on the CC line Shall remain below vNoiseIdle and vNoiseActive. Sink Port Current Source Port Voltage vSrcNew(max)/ vSrcPeak(max) Nominal Voltage vSrcNew(min) vSrcPeak(min) IOC level as requested in the Operating Current field of an RDO % level with respect to IOC as advertised in the Peak Current field of Fixed Supply PDO Additional operating range for Fixed Supply that supports overload capability Operating range for supply that DOES NOT support overload capability Page 330 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Test conditions require a change in both positive and negative load steps from 1Hz to 5000Hz, up to the Advertised Load Step Magnitude of the full load output including from both 10 mA and 10% initial load. The Source Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks" under all load conditions. 7.1.12.1.2 Load Step Magnitude The default load step magnitude rate Shall be 25% of IoC. The Source May report higher capability tolerating a load step of 90% of IoC. 7.1.12.2 Holdup Time Field The Holdup Time field Shall return a numeric value of the number of milliseconds the output voltage stays in regulation upon a short interruption of the AC Supply. An AC Supplied Source Shall report its holdup time in this field. The holdup time is measured with the load at rated maximum, with the AC Supply at 115VAC rms and 60Hz (or at 230VAC rms and 50Hz for a Source that does not support 115VAC AC Supply). The reported time describes the minimum length of time from the last completed AC Supply input cycle (zero-degree phase angle) until when the output voltage decays below vSrcValid (min). Sources are recommended to support a minimum of 3ms and are preferred to support over 10 milliseconds holdup time (equivalent to a half cycle drop from the AC Supply). See Figure 7.15, "Holdup Time Measurement". Figure 7.15 Holdup Time Measurement 7.1.12.3 Compliance Field An SPR Source claiming LPS, PS1 or PS2 compliance (see [IEC 62368-1]) Shall report its Capabilities in the Compliance field. Since the SPR Source May have several potential output voltage and current settings, every SPR Source supply (each indicated by a PDO) Shall be compliant to LPS requirements. Note: According to the requirements of [IEC 60950-1] and/or [IEC 62368-3], a device tested and certified with an LPS Source (SPR Source or EPR Source operating in SPR Mode) is prohibited from using a non-LPS Source (EPR Source operating in EPR Mode). Alternatively, [IEC 62368-1], classifies power sources according to their maximum, constrained power output (15watts or 100watts). 7.1.12.4 Peak Current The Source reports its ability to source peak current delivery in excess of the Negotiated amount in the Peak Current field. The duration of peak current Shall be followed by a current consumption below the Operating Current (IoC) in order to maintain average power delivery below the IoC current. vSrcValid(min) Hold Up Time у VBUS AC mains voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 331 A Source May have greater capability to source peak current than can be reported using the Peak Current field in the Fixed Supply PDO or AVS APDO. In this case the Source Shall report its additional capability in the Peak Current1/Peak Current2/Peak Current3 fields in the Source_Capabilities_Extended Message. Each overload period Shall be followed by a period of reduced current draw such that the rolling average current over the Overload Period field value with the specified Duty Cycle field value (see Section 6.5.1.10, "Peak Current Field") Shall Not exceed the Negotiated current. This is calculated as: Period of reduced current = (1 - value in Duty Cycle field/100) * value in Overload Period field 7.1.12.5 Source Inputs The Source Inputs field identifies the possible inputs that provide power to the Source. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. 7.1.12.6 Batteries The Number of Batteries/Battery Slots field Shall report the number of Batteries the Source supports. The Source Shall independently report the number of Hot Swappable Batteries and the number of Fixed Batteries. 7.1.13 Fast Role Swap A Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port supporting DRP as shown in Figure 7.16, "VBUS Power during Fast Role Swap". Figure 7.16 VBUS Power during Fast Role Swap When the power source connected to the Hub UFP stops sourcing power and VBUS at the Hub DRP connector discharges below vSrcValid(min), if VBUS has been Negotiated to a higher voltage than vSafe5V, or vSafe5V (min) the Fast Role Swap Request Shall be sent from the Hub DRP to the Host DRP and the Hub DRP Shall sink power. In the Fast Role Swap use case, the Hub DRP behaves like a bidirectional power path. The Hub DRP Shall Not enable VBUS discharge circuitry when changing operation from Initial Source to New Sink. The Hub DFP Port(s) Shall support default USB Type-C Current (see [USB Type-C 2.4]) until a new Explicit Contract is Negotiated. After sending the Fast Role Swap Request and while VBUS > vSafe5V (min), the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. The New Sink Shall Not draw more than iSnkStdby from VBUS until tSnkFRSwap after it has started sending the Fast Role Swap Request or VBUS has fallen below vSafe5V (min). The tSnkFRSwap time Shall start at the beginning of the Fast Role Swap Request or when VBUS falls below vSafe5V (min), whichever comes later. After waiting for tSnkFRSwap, the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. After the New Source has applied its Rp, the New Sink Shall be limited to USB Type-C Current (see [USB Type-C 2.4]) in an Implicit Contract until a new Explicit Contract is Negotiated. All Sink requirements Shall apply to the New Sink after the Fast Role Swap is complete. The Fast Role Swap response of the Host DRP is described in Section 7.2.10, "Fast Role Swap" since the Host DRP is operating as the Initial Sink prior to the Fast Role Swap. After the VBUS voltage level at the Hub DRP connector drops below vSafe5V a PS_RDY Message Shall be sent to the Host DRP as shown in the Fast Role Swap transition diagram of Section 7.3.4, "Transitions Caused by Fast Role Swap". USB PD Capable Hub DRP UFP DFP Power Source Bus Powered Accessory USB PD Capable Host DRP Power flow before the Fast Role Swap Power flow after the Fast Role Swap Page 332 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.17, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min)" and Figure 7.18, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min)" show the VBUS detection and timing for the New Source during a Fast Role Swap after the Fast Role Swap Request has been received. The New Source May turn on the VBUS output switch once VBUS is below vSafe5V (max). In this case, the New Source prevents VBUS from falling below vSafe5V (min). The new source Shall turn on the VBUS output switch within tSrcFRSwap of falling below vSafe5V (min). VBUS might have started at vSafe5V or at higher voltage. When the Fast Role Swap Request is detected, VBUS could therefore be either above vSafe5V (max), within the vSafe5V range, or below vSafe5V (min). If the Fast Role Swap Request is detected when VBUS is below vSafe5V (min), then the new source Shall turn on the VBUS output switch within tSrcFRSwap of detecting the Fast Role Swap Request. In this case, the maximum time from the beginning of the Fast Role Swap Request to VBUS being sourced May be tSrcFRSwap (max) + tFRSwapRx (max). Figure 7.17 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min) Figure 7.18 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min) 7.1.14 Non-application of VBUS Slew Rate Limits Scenarios where vSrcSlewPos and vPpsSlewPos VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When first applying VBUS after an Attach.  When applying VBUS as part of a Power Role Swap to Source Power Role.  When increasing VBUS from vSafe0V to vSafe5V during a Hard Reset.  During a Fast Role Swap when the Initial Sink applies VBUS. Old Voltage 0V vSafe5V(min) tSrcFRSwap vSafe5V(max) § New Source may turn on at any time after VBUS falls below vSafe5V(max) VBUS Old Source detects power loss and signals Fast Role Swap Old Voltage 0V vSafe5V(min) tSrcFRSwap VBUS is below vSafe5V(min) before FRS signal is finished Old Source detects power loss and signals Fast Role Swap tFRSwapRx (max) VBUS at new Source CC New Source may turn on after detecting Fast Role Swap signal Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 333 Scenarios where vSrcSlewNeg and vPpsSlewNeg VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When discharging VBUS to vSafe0V during a Hard Reset.  When discharging VBUS to vSafe0V as part of a Power Role Swap to Sink Power Role.  When discharging VBUS to vSafe0V after a Detach.  During a Fast Role Swap when the VBUS power source connected to the Hub UFP stops sourcing power. 7.1.15 VCONN Power Cycle 7.1.15.1 UFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the UFP is the VCONN Source, the following steps Shall be followed:  Following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message, the UFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type- C 2.4]) within tVCONNZero.  When VCONN is below vRaReconnect, the UFP Shall send a PS_RDY Message. Note: If the UFP was not sourcing VCONN, it still sends the PS_RDY Message.  The DFP Shall wait tVCONNReapplied following the last bit of the GoodCRC Message acknowledging the PS_RDY Message before sourcing VCONN. The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.19, "Data Reset UFP VCONN Power Cycle" below illustrates the UFP VCONN Power Cycle process. Figure 7.19 Data Reset UFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied PS_RDY (UFP) UFP DFP Page 334 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.15.2 DFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the DFP is the VCONN Source, the following steps Shall be followed: 1) If the DFP sent the Data_Reset Message and is sourcing VCONN then it Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero of the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 2) If the UFP sent the Data_Reset Message then the DFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 3) When VCONN is below vRaReconnect, the DFP Shall wait tVCONNReapplied before sourcing VCONN. 4) The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.20, "Data Reset DFP VCONN Power Cycle" below illustrates the DFP VCONN Power Cycle process. Figure 7.20 Data Reset DFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied UFP DFP
7.2 - Sink Requirements..................................................................................................................... (Page 335)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 335 7.2 Sink Requirements 7.2.1 Behavioral Aspects A PDUSB Sink exhibits the following behaviors:  Shall Not draw more than [USB Type-C 2.4] USB Type-C Current from VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS in-rush current when increasing current consumption according to [USB 2.0] or [USB 3.2] as appropriate. 7.2.2 Sink Bulk Capacitance The Sink bulk capacitance consists of C3 and C4 as shown in Figure 7.21, "Placement of Sink Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect is expected to be part of an input Over Voltage Protection (Sink OVP) circuit implemented by the Sink as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. A Sink Shall implement OVP. The Sink Shall Not rely on the Source output voltage limit for its input OVP. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. An upper bound of cSnkBulkPd Shall Not be exceeded so that the transient charging, or discharging, of the total bulk capacitance on VBUS can be accounted for during voltage transitions. The Sink bulk capacitance that is within the cSnkBulk max or cSnkBulkPd max limits is allowed to change to support a newly Negotiated power level. The capacitance can be changed when the Sink enters Sink Standby or during a voltage transition or when the Sink begins to operate at the new power level. Changing the Sink bulk capacitance Shall Not cause a transient current on VBUS that violates the present Contract. During a Power Role Swap the Default Sink Shall transition to Swap Standby before operating as the New Source. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.21 Placement of Sink Bulk Capacitance 7.2.3 Sink Standby The Sink Shall transition to Sink Standby before a positive voltage transition of VBUS. During Sink Standby the Sink Shall reduce the current drawn to iSnkStdby. This allows the Source to manage the voltage transition as well as supply sufficient operating current to the Sink to maintain PD operation during the transition. The Sink Shall complete this transition to Sink Standby within tSnkStdby after evaluating the Accept Message from the Source. The transition when returning to Sink operation from Sink Standby Shall be completed within tSnkNewPower. The iSnkStdby requirement Shall only apply if the Sink current draw is higher than this level. See Section 7.3, "Transitions" for details. GND SHIELD VBUS ... Data Lines C3 GND SHIELD VBUS ... Data Lines SINK CABLE C4 Load Sink Bulk Capacitance Ohmic Interconnect OVP Page 336 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.3.1 Programmable Power Supply Sink Standby A Sink is not required to transition to Sink Standby when operating within the Negotiated PPS APDO. A Sink May consume the Operating Current value in the PPS RDO during PPS output voltage changes. However, prior to operating the SPR PPS in Current Limit, the Sink Shall program the PPS Operating Voltage to the lowest practical level that satisfies the Sink load requirement. Doing so will minimize the inrush current that occurs when the transition to Current Limit occurs. When operating with an SPR PPS Source that is in Current Limit, the Sink Shall Not change its load in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The load change magnitude Shall Not request a change to the Current Limit set-point that exceeds iPpsCLLoadStep. If the Sink Negotiates for a new PPS APDO, that is expected to increase VBUS voltage, then the Sink Shall transition to Sink Standby while changing between PPS APDOs as described in Section 7.3.1, "Transitions caused by a Request Message". 7.2.4 Suspend Power Consumption When Source has set its USB Suspend Supported flag (see Section 6.4.1.2.1.2, "USB Suspend Supported"), a Sink Shall go to the lowest power state during USB suspend. The lowest power state Shall be pSnkSusp or lower for a PDUSB Peripheral and pHubSusp or lower for a PDUSB Hub. There is no requirement for the Source voltage to be changed during USB suspend. 7.2.5 Zero Negotiated Current When a Sink Requests zero current as part of a power Negotiation with a Source, the Sink Shall go to the lowest power state, pSnkSusp or lower, where it can still communicate using PD signaling. 7.2.6 Transient Load Behavior When a Sink's operating current changes due to a load step, load release or any other change in load level, the positive or negative overshoot of the new load current Shall Not exceed the range defined by iOvershoot. For the purposes of measuring iOvershoot the new load current value is defined as the average steady state value of the load current after the load step has settled. The rate of change of any shift in Sink load current during normal operation Shall Not exceed iLoadStepRate (for load steps) and iLoadReleaseRate (for load releases) as measured at the Sink receptacle. The Sink's operating current Shall Not change faster than the value reported in the Source's Load Step Slew Rate in its Voltage Regulation bit field and Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks". 7.2.7 Swap Standby for Sinks The Sink functionality in a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Sink after evaluating the Accept Message from the Source during a Power Role Swap. While in Swap Standby the Sink's current draw Shall Not exceed iSnkSwapStdby from VBUS and the Dual-Role Power Port Shall be configured as a Source after VBUS has been discharged to vSafe0V by the existing Initial Source. The Sink's USB connection Should Not be reset even though vSafe5V is not present on the VBUS conductor (see Section 9.1.2, "Mapping to USB Device States"). The time for the Sink to transition to Swap Standby Shall be no more than tSnkSwapStdby. When in Swap Standby the Sink has relinquished its Power Role as Sink and will prepare to become the New Source. The transition time from Swap Standby to New Source Shall be no more than tNewSrc. 7.2.8 Sink Peak Current Operation Sinks Shall only make use of a Source overload capability when the corresponding Fixed Supply PDO Peak Current (see Section 6.4.1.2.1.8, "Peak Current") or AVS APDO Peak Current (see Section 6.4.1.2.4.3.2, "Peak Current") bits are set to 01b, 10b and 11b. Sinks Shall manage thermal aspects of the overload event by not exceeding the average Negotiated output of a Fixed Supply or AVS that supports Peak Current operation. Sinks that depend on the Peak Current capability for enhanced system performance Shall also function correctly when Attached to a Source that does not offer the Peak Current capability or when the Peak Current capability has been inhibited by the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 337 7.2.9 Robust Sink Operation 7.2.9.1 Sink Bulk Capacitance Discharge at Detach When a Source is Detached from a Sink, the Sink Shall continue to draw power from its input bulk capacitance until VBUS is discharged to vSafe5V or lower by no longer than tSafe5V from the Detach event. This safe Sink requirement Shall apply to all Sinks operating with a Negotiated VBUS level greater than vSafe5V and Shall apply during all low power and high-power operating modes of the Sink. If the Detach is detected during a Sink low power state, such as USB Suspend, the Sink can then draw as much power as needed from its bulk capacitance since a Source is no longer Attached. In order to achieve a successful Detach detect based on VBUS voltage level droop, the Sink power consumption Shall be high enough so that VBUS will decay below vSrcValid(min) well within tSafe5V after the Source bulk capacitance is removed due to the Detach. Once adequate VBUS droop has been achieved, a discharge circuit can be enabled to meet the safe Sink requirement. To illustrate the point, the following set of Sink conditions will not meet the safe Sink requirement without additional discharge circuitry:  Negotiated VBUS = 20V.  Maximum allowable supplied VBUS voltage = 21.55V.  Maximum bulk capacitance = 30µF.  Power consumption at Detach = 12.5mW. When the Detach occurs (hence removal of the Source bulk capacitance) the 12.5mW power consumption will draw down the VBUS voltage from the worst-case maximum level of 21.55V to 17V in approximately 205ms. At this point, with VBUS well below vSrcValid (min) an approximate 100mW discharge circuit can be enabled to increase the rate of Sink bulk capacitance discharge and meet the safe Sink requirement. The power level of the discharge circuit is dependent on how much time is left to discharge the remaining voltage on the Sink bulk capacitance. If a Sink has the ability to detect the Detach in a different manner and in much less time than tSafe5V, then this different manner of detection can be used to enable a discharge circuit, allowing even lower power dissipation during low power modes such as USB Suspend. In most applications, the safe Sink requirement will limit the maximum Sink bulk capacitance well below the cSnkBulkPd limit. A Detach occurring during Sink high power operating modes must quickly discharge the Sink bulk capacitance to vSafe5V or lower as long as the Sink continues to draw adequate power until VBUS has decayed to vSafe5V or lower. 7.2.9.2 Input Over Voltage Protection Sinks Shall implement input Over-Voltage Protection (OVP) to prevent damage from input voltage that exceeds the voltage handling capability of the Sink. The definition of voltage handling capability is left to the discretion of the Sink implementation. The over voltage response of Sinks Shall Not interfere with normal PD operation and Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid as determined by the Negotiated VBUS value. SPR Sinks Should tolerate input voltages as high as vSprMax and Shall meet applicable safety requirements if vSprMax is exceeded. Likewise, EPR Sinks Should tolerate input voltages as high as vEprMax and Shall meet applicable safety requirements if vEprMax is exceeded. Sinks Should attempt to send Hard Reset Signaling when OVP engages followed by an Alert Message indicating an OVP event once an Explicit Contract has been established. The OVP response May engage at either the Port or system level. Systems or ports that have engaged OVP Shall resume USB Default Operation when the Source has re- established vSafe5V on VBUS. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an OVP event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if OVP continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over voltage. Page 338 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.9.3 Over Temperature Protection Sinks Shall implement over temperature protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Sink. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Sink implementation. Sinks Shall attempt to send Hard Reset Signaling when over temperature protection engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The over temperature protection response May engage at either the Port or system level. Systems or ports that have engaged over temperature protection Should attempt to resume USB Default Operation after sufficient cooling is achieved and May latch off to protect the Port or system. The definition of sufficient cooling is left to the discretion of the Sink implementation. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an over temperature event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. 7.2.9.4 Over Current Protection Sinks that operate with a Programmable Power Supply Shall implement their own internal current protection mechanism to protect against internal VBUS current faults as well as erratic Source current regulation. The Sink Shall never draw higher current than the Maximum Current value in the PPS APDO. 7.2.10 Fast Role Swap As described in Section 7.1.13, "Fast Role Swap" a Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port that supports DRP. This configuration is shown in Figure 7.16, "VBUS Power during Fast Role Swap". The Host DRP, upon establishing an Explicit Contract, Shall query the Initial Source's Sink Capabilities to determine whether the Initial Source supports Fast Role Swap, and what level of current it requires. If the Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap required USB Type-C Current bits set, and the Host DRP is able to source the requested current at 5V, the Host DRP May arm itself for Fast Role Swap. If the Host DRP has not queried the Sink Capabilities from the Initial Source, or if the Sink_Capabilities Message reports no Fast Role Swap support or a current that is beyond what the Host DRP is able or willing to source in the event of a Fast Role Swap, the Host DRP Shall Not arm itself for Fast Role Swap and Shall Ignore any Fast Role Swap Requests that are detected. When the Host DRP that supports Fast Role Swap detects the FFast Role Swap Request, the Host DRP Shall stop sinking current and Shall be ready and able to source vSafe5V if the residual VBUS voltage level at the Host DRP connector is greater than vSafe5V. When the residual VBUS voltage level at the Host DRP connector discharges below vSafe5V(min) the Host DRP as the New Source Shall supply vSafe5V to the Hub DRP within tSrcFRSwap. The Host DRP Shall Not enable VBUS discharge circuitry when changing Power Roles from Initial Sink to New Source. The New Source Shall supply vSafe5V at USB Type-C Current (see [USB Type-C 2.4]) at the value Advertised in the Fast Role Swap required USB Type-C Current field (see Section 6.4.1.3.1.6, "Fast Role Swap USB Type-C Current"). All Source requirements Shall apply to the New Source after the Fast Role Swap is complete The Fast Role Swap response of the Hub DRP is described in Section 7.1.13, "Fast Role Swap" since the Hub DRP is operating as the Initial Source prior to the Fast Role Swap. After the Host DRP is providing VBUS power to the Hub DRP, a PS_RDY Message Shall be sent to the Hub DRP as defined by the Fast Role Swap Request and the AMS detailed in Section 7.3.4, "Transitions Caused by Fast Role Swap".
7.3 - Transitions..................................................................................................................................... (Page 339)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 339 7.3 Transitions The following sections illustrate the power supply's response to various types of Negotiations. The Negotiations are triggered by certain Messages or Signaling. It provides examples of the transitions and is organized around each of the Messages and Signals that result in a response from the power supply. The response to a Message or Signal can result in different transitions depending upon the power supply's starting conditions and the requested change.  Transitions caused by a Request Message:  Generic transition between (A)PDO s:  Increase the current.  Increase the voltage.  Increase the voltage and the current.  Increase the voltage and decrease the current.  Decrease the voltage and increase the current.  Decrease the voltage and the current.  No change in Current or voltage.  Transitions within the same PDO (Fixed Supply, Battery Supply, Variable Supply):  Increase the current.  Decrease the current.  No change in current.  Transitions within the same PPS APDO:  Increasing the Programmable Power Supply (PPS) voltage.  Decreasing the Programmable Power Supply (PPS) voltage.  Increasing the Programmable Power Supply (PPS) Current.  Decreasing the Programmable Power Supply (PPS) Current.  Same Request Programmable Power Supply (PPS).  Transitions within the same AVS APDO:  Increasing the Adjustable Voltage Supply (AVS) voltage  Decreasing the Adjustable Voltage Supply (AVS) voltage  Same Request Adjustable Voltage Supply (AVS)  Transitions caused by the PR_Swap Message:  Source requests a Power Role Swap  Sink requests a Power Role Swap  Transitions caused by Hard Reset Signaling:  Source issues Hard Reset Signaling.  Sink issues Hard Reset Signaling.  Transitions caused by the Fast Role Swap Request:  Source asserts Rd at its preferred [USB Type-C 2.4] current. Page 340 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1 Transitions caused by a Request Message This section describes transitions that are caused by a Request Message. 7.3.1.1 Changing the Source between Different (A)PDOs In these transition descriptions the term (A)PDO is used to describe any Power Data Object, regardless of whether it is a PDO or an APDO in the Capabilities Message. This section describes transitions in response to a Request Message:  From one (A)PDO to another (A)PDO  From an Implicit Contract to an Explicit Contract  From [USB Type-C 2.4]operation to the First Explicit Contract These transitions usually result in a voltage change but is not required. The interaction of the Device Policy Manager, the Port Policy Engine and the Power Supply that Shall be followed when increasing the current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current" and Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The Source voltage as the transition starts Shall be any voltage within the Valid VBUS range of the previous Source PDO or APDO. The Source voltage after the transition is complete Shall be any voltage within the Valid VBUS range of the New Source PDO or APDO. The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current" and Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In this figure, the Sink has previously sent a Request Message to the Source. The voltage is considered to increase if the change from VOLD to VNEW is greater than vSmallStep. The determination Shall be based on the nominal (A)PDO voltage before and after, unless either (A)PDO is Battery Supply or Variable Supply when the worst case of the following is assumed in making this determination.  Minimum voltage to voltage.  Minimum voltage to Maximum voltage.  Voltage to Maximum voltage. The following sections begin with a description of the generic process followed by more specific examples of the most common transitions. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 341 7.3.1.1.1 Examples of changes from one (A)PDO to another (A)PDO The seven examples of (A)PDO change transitions below illustrate the most common transitions. 7.3.1.1.1.1 Increasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage is shown in Figure 7.22, "Transition Diagram for Increasing the Voltage". The sequence that Shall be followed is described in Table 7.1, "Sequence Description for Increasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.22, "Transition Diagram for Increasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 342 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.22 Transition Diagram for Increasing the Voltage t3 t1 t2 Source VOLD Source VNEW Source × V 4 3 7 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply 8 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,2/' Sink ” IOLD ” IOLD ” IOLD Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) VNEW I1 ... § Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 343 Table 7.1 Sequence Description for Increasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 344 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.2 Increasing the Voltage and Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current". The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.23, "Transition Diagram for Increasing the Voltage and Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 345 Figure 7.23 Transition Diagram for Increasing the Voltage and Current t3 Source VOLD Source VNEW Source × V × I 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ”INEW Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD VNEW 3 7 I1 § ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) t2 t1 Page 346 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.2 Sequence Diagram for Increasing the Voltage and Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out, the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 347 7.3.1.1.1.3 Increasing the Voltage and Decreasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and decreasing the current is shown in Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current". The sequence that Shall be followed is described in Table 7.3, "Sequence Description for Increasing the Voltage and Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current", the Sink has previously sent a Request Message to the Source. Page 348 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.24 Transition Diagram for Increasing the Voltage and Decreasing the Current t3 t1 Source VOLD Source VNEW Source × V ØI 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW I1 Sink to Sink Standby Sink Standby to Sink Sink iSnkStdBy VNEW VOLD 3 7 ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) § t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 349 Table 7.3 Sequence Description for Increasing the Voltage and Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 350 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.4 Decreasing the Voltage and Increasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and increasing the current is shown in Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The sequence that Shall be followed is described in Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 351 Figure 7.25 Transition Diagram for Decreasing the Voltage and Increasing the Current t2 Source VOLD Source VNEW Source Ø V × I 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW VNEW VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink × I ... 6 7 t1 Page 352 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.4 Sequence Description for Decreasing the Voltage and Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the PS_RDY Message from the Source and tells the Device Policy Manager it is okay to operate at the new power level. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 353 7.3.1.1.1.5 Decreasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage is shown in Figure 7.26, "Transition Diagram for Decreasing the Voltage". The sequence that Shall be followed is described in Table 7.5, "Sequence Description for Decreasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.26, "Transition Diagram for Decreasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 354 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.26 Transition Diagram for Decreasing the Voltage t Source VOLD Source Ø V 3 Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”IOLD VOLD ” IOLD ” IOLD VNEW Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 355 Table 7.5 Sequence Description for Decreasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 356 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.6 Decreasing the Voltage and the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and current is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.6, "Sequence Description for Decreasing the Voltage and the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.27, "Transition Diagram for Decreasing the Voltage and the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 357 Figure 7.27 Transition Diagram for Decreasing the Voltage and the Current t1 t2 Source Ø V Ø I 4 Source VOLD Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”INEW Sink ”IOLD ” IOLD ” INEW Sink Ø I VNEW VOLD 3 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Page 358 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.6 Sequence Description for Decreasing the Voltage and the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 359 7.3.1.1.1.7 No change in Current or Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while the Sink requests the same voltage and Current as it is currently operating at is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.7, "Sequence Description for no change in Current or Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.28, "Transition Diagram for no change in Current or Voltage", the Sink has previously sent a Request Message to the Source. Page 360 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.28 Transition Diagram for no change in Current or Voltage Table 7.7 Sequence Description for no change in Current or Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine waits tSrcTransition then sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine evaluates the PS_RDY Message. Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink ”IOLD VBUS doesn’t change Source VOLD Current doesn’t change Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tSrcTransition Good CRC Good CRC tSrcTransReq Vold Source VOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 361 7.3.1.2 Transitions within the same Fixed, Battery or Variable PDO or between Different (A)PDOs 7.3.1.2.1 Increasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current without changing the voltage is shown in Figure 7.29, "Transition Diagram for Increasing the Current". The sequence that Shall be followed is described in Table 7.8, "Sequence Description for Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.29, "Transition Diagram for Increasing the Current", the Sink has previously sent a Request Message to the Source. Page 362 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.29 Transition Diagram for Increasing the Current Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Sink ”INEW Source Port Voltage Sink Port Current Sink ”IOLD ” IOLD ” INEW Sink × I VBUS doesn’t change Source × I 3 6 ... 7 § Source VOLD Source VOLD Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Port to Port Messaging Good CRC tSrcTransReq Good CRC Sink Port Policy Engine t1 t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 363 Table 7.8 Sequence Description for Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t2) depends on the magnitude of the load change. Page 364 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.2.2 Decreasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current without changing the voltage is shown in Figure 7.30, "Transition Diagram for Decreasing the Current". The sequence that Shall be followed is described in Table 7.9, "Sequence Description for Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.30, "Transition Diagram for Decreasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 365 Figure 7.30 Transition Diagram for Decreasing the Current Source VOLD Source VOLD Sink ”IOLD Sink ”INEW VBUS does not change Source Ø I 4 3 ” IOLD ” INEW Sink Ø I Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC t1 t2 Page 366 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.9 Sequence Description for Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. Policy Engine tells the Device Policy Manager to instruct the power supply to reduce power consumption. 3 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 367 7.3.1.3 Changing Voltage or Current within the same PPS APDO 7.3.1.3.1 Increasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.10, "Sequence Description for Increasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Page 368 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.31 Transition Diagram for Increasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Current may change (not to exceed negotiated current) Source CL Current Sink VBUS Current Sink Port Current VOLD Source Port Voltage VNEW Source VBUS Voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 369 Table 7.10 Sequence Description for Increasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to increase its output voltage. The Programmable Power Supply new voltage set- point Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new set-point and whether VBUS is at the corresponding new level, or if the supply is operating in CL mode. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 370 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.2 Decreasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.11, "Sequence Description for Decreasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 371 Figure 7.32 Transition Diagram for Decreasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Source CL Current Current may change (not to exceed negotiated current) Sink VBUS Current Sink Port Current Page 372 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.11 Sequence Description for Decreasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to decrease its output voltage. The Programmable Power Supply new voltage set- point (corresponding to vPpsNew) Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 373 7.3.1.3.3 Increasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current limit in the same APDO, not exceeding the maximum for that APDO and without changing the requested voltage is shown in Figure 7.33, "Transition Diagram for increasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.12, "Sequence Description for increasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.33, "Transition Diagram for increasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. The Sink May draw current equal to the increasing Current Limit of the Source before it has received the PS_RDY Message for the new Request. Page 374 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.33 Transition Diagram for increasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ĺ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 375 Table 7.12 Sequence Description for increasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Power Supply increases its Current Limit set- point to the new requested value. The Sink draws current according to the increased Current Limit of the Source. 4 The Policy Engine waits tPpsSrcTransSmall then sends the PS_RDY Message to the Sink starting within tPpsCLProgramSettle of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. 6 Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message and tells the Device Policy Manager it can increase the current up to the requested value without the Source going into CL mode. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink increases its current. Page 376 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.4 Decreasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current limit in the same APDO, not exceeding the minimum for that APDO and without changing the requested voltage is shown in Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.13, "Sequence Description for decreasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 377 Figure 7.34 Transition Diagram for decreasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ļ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Set-point V does not change, only resulting V Page 378 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.13 Sequence Description for decreasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and instructs the Sink to reduce its current to below the new Negotiated current level and starts the PSTransitionTimer. 3 The Power Supply decreases its Current Limit set- point to the new Negotiated value. The Sink reduces its current to less than the new Negotiated current to prevent the Source from going into Current Limit. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Policy Engine receives the PS_RDY Message. 6 Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink is allowed to draw INEW but must be aware the voltage on VBUS can drop doing so. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 379 7.3.1.3.5 Same Request Programmable Power Supply (PPS) The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current is shown in Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode". The sequence that Shall be followed is described in Table 7.14, "Sequence Description for no change in Current or Voltage in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode", the Sink has previ- ously sent a Request Message to the Source. Page 380 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.35 Transition Diagram for no change in Current or Voltage in PPS mode Table 7.14 Sequence Description for no change in Current or Voltage in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and starts the PSTransitionTimer. 3 The Policy Engine then sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Source IOLD Sink ” IOLD Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD Sink Port Current Source CL Current CL doesn’t change Current doesn’t change VBUS doesn’t change Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 381 7.3.1.4 Changing Voltage or Current within the same AVS APDO 7.3.1.4.1 Increasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.15, "Sequence Description for Increasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed inTable 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage", the Sink has pre- viously sent a Request Message to the Source. Page 382 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.36 Transition Diagram for Increasing the Adjustable Power Supply Voltage AVS Transition Interval Source VOLD Source VNEW Sink draws current continuously for voltage changes less than or equal to vAvsSmallStep. For larger voltage changes, the Sink reduces to iSnkStdby. IOLD VOLD Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Depends on magnitude of AVS voltage change Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 383 Table 7.15 Sequence Description for Increasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. If the voltage increase is larger than vAvsSmallStep, the Sink Shall reduce its current draw to iSnkStdby within tSnkStdby. The reduction to iSnkStdby is not required if the voltage increase is less than or equal to vAvsSmallStep. 3 After sending the Accept Message, the AVS starts to increase its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point. The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 384 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.4.2 Decreasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage". The sequence that Shall be followed is described in Table 7.16, "Sequence Description for Decreasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 385 Figure 7.37 Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage AVS Transition Interval Source VOLD Source VNEW ”IOLD VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Sink ”IOLD Page 386 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.16 Sequence Description for Decreasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the AVS starts to decrease its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vAvsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 387 7.3.1.4.3 Same Request Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current as shown in Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode". The sequence that Shall be followed is described in Table 7.17, "Sequence Description for no change in Current or Voltage in AVS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode", the Sink has previ- ously sent a Request Message to the Source. Figure 7.38 Transition Diagram for no change in Current or Voltage in AVS mode Table 7.17 Sequence Description for no change in Current or Voltage in AVS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 4 Protocol Layer receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Current doesn’t change VBUS doesn’t change Source Port Policy Engine Sink Port Policy Engine Source Port Voltage Sink Port Current Port to Port Messaging Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Page 388 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2 Transitions Caused by Power Role Swap 7.3.2.1 Sink Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink requested Power Role Swap is shown in Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.18, "Sequence Description for a Sink Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap", the Sink has previously sent a PR_Swap Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 389 Figure 7.39 Transition Diagram for a Sink Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 3 4 7 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSSourceOffTimer tSrcTransition Good CRC tSrcTransOff Good CRC PSSourceOnTimer Send PS_RDY Evaluate PS_RDY Good CRC 8 9 tSrcTransOn Page 390 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.18 Sequence Description for a Sink Requested Power Role Swap Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port 1 Policy Engine sends the Accept Message to the Initial Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Initial Source. Policy Engine then starts the PSSourceOffTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition min. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 5 The power supply is ready, and the Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. 6 Protocol Layer receives the GoodCRC Message from the device that will become the New Source. Policy Engine starts the PSSourceOnTimer. Upon sending the PS_RDY Message and receiving the GoodCRC Message the Initial Source is ready to be the New Sink. The Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine the stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 8 Policy Engine receives the PS_RDY Message from the Source. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 391 9 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 10 The power supply as the New Sink transitions from Swap Standby and begins to drawing the current allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.18 Sequence Description for a Sink Requested Power Role Swap (Continued) Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port Page 392 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2.2 Source Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source requested Power Role Swap is shown in Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.19, "Sequence Description for a Source Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap", the Source has previously sent a PR_Swap Message to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 393 Figure 7.40 Transition Diagram for a Source Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 2a 4 6 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSSourceOffTimer (running) tSrcTransition Good CRC Good CRC PSSourceOnTimer (running) Send PS_RDY Evaluate PS_RDY Good CRC 7 9 Page 394 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.19 Sequence Description for a Source Requested Power Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port 1 Policy Engine receives the Accept Message. Policy Engine sends the Accept Message to the Initial Source. 2 Protocol Layer sends the GoodCRC Message to the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer receives the GoodCRC Message from the Initial Source. Policy Engine starts the PSSourceOffTimer. 2a The Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby. The power supply Shall complete the transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). 3 tSrcTransition after the GoodCRC Message was sent the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY. 5 Protocol Layer receives the GoodCRC Message from the soon to be New Source. Policy Engine starts the PSSourceOnTimer. At this point the Initial Source is ready to be the New Sink. Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine then stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before the PSSourceOffTimer times out the Sink starts sending Hard Reset Signaling. 6 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 7 Policy Engine receives the PS_RDY Message. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 395 8 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 9 The power supply as the New Sink transitions from Swap Standby to drawing the power allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The New Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.19 Sequence Description for a Source Requested Power Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 396 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3 Transitions Caused by Hard Reset 7.3.3.1 Source Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source Initiated Hard Reset is shown in Figure 7.41, "Transition Diagram for a Source Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.20, "Sequence Description for a Source Initiated Hard Reset". The timing parameters that Shall be applied are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 397 Figure 7.41 Transition Diagram for a Source Initiated Hard Reset Table 7.20 Sequence Description for a Source Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Sink. Sink receives Hard Reset Signaling. 2 Policy Engine is informed of the Hard Reset. Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine waits tPSHardReset after sending Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 5 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 Source VOLD Send Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 vSafe5V Default current draw § § Source vSafe5V 4 Source vSafe0V Sink ” IOLD Ready to recover and power up Source Recover tSrcRecover 5 Process Hard Reset tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current 2 t2 t1 Page 398 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3.2 Sink Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink Initiated Hard Reset is shown in Figure 7.42, "Transition Diagram for a Sink Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.21, "Sequence Description for a Sink Initiated Hard Reset". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 399 Figure 7.42 Transition Diagram for a Sink Initiated Hard Reset Table 7.21 Sequence Description for a Sink Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Source. 2 Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager. The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine is informed of the Hard Reset. 5 Policy Engine waits tPSHardReset after receiving Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 6 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 t2 Send Hard Reset Evaluate Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 4 vSafe5V Defalt current draw § § Source vSafe5V 5 Source vSafe0V Sink ” IOLD Source VOLD Ready to recover and power up Source Recover tSrcRecover 6 tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Process Hard Reset 2 t1 Page 400 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.4 Transitions Caused by Fast Role Swap 7.3.4.1 Fast Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Fast Role Swap is shown in Figure 7.43, "Transition Diagram for Fast Role Swap". The parallel sequences that Shall be followed are described in Table 7.22, "Sequence Description for Fast Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Negotiations between the New Source and the New Sink May occur after the New Source sends the final PS_RDY Message. Note: In Figure 7.43, "Transition Diagram for Fast Role Swap". and Table 7.22, "Sequence Description for Fast Role Swap" numbers are used to indicate Message related steps and letters are used to indicate other events. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 401 Figure 7.43 Transition Diagram for Fast Role Swap Rp Changed to Rd Signal Fast Swap Detect Fast Swap Old Sink New Sink Old Source A B 2 C Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Path Sink Port Device Policy Mgr Sink Port Power Path Source Port Voltage Sink Port Current Port to Port Signaling & Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Stops Send FR_Swap 1 Send Accept Evaluate FR_Swap New Source = vSafe5V Evaluate Accept 3 4 Send PS_RDY Evaluate PS_RDY D1 Sink 5 6 Source VBUS< vSafe5V Send PS_RDY 7 VBUS< vSafe5V Source VBUS Source vSafe5V D2 E Ready & Able to Source vSafe5V Evaluate PS_RDY 8 tFRSwapInit Rd Changed to Rp F G 0 A < tSrcFRSwap discharging Sink 0 V Any voltage > vSafe5V No current may be drawn while VBUS is below vSafe5V Page 402 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.22 Sequence Description for Fast Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Fast Role Swap Request and Power Transition A The Source connected to the Hub UFP (see Figure 7.16, "VBUS Power during Fast Role Swap") stops sourcing VBUS. B Policy Engine sends the Fast Role Swap Request to the Initial Sink on the CC wire. When VBUS < vSafe5V (min), it tells the Device Policy Manager not to draw more than iSnkStdby until the tSnkFRSwap timer has elapsed. C Policy Engine detects the Fast Role Swap Request on the CC wire from the Initial Source and Shall send the FR_Swap Message back to the Initial Source (that is no longer powering VBUS) within time tFRSwapInit. D1 The Policy Engine monitors for VBUS ≤ vSafe5V so that a PS_RDY Message can be sent to the New Source at Step 5 of the messaging sequence. D2 The Policy Engine monitors for VBUS ≤ vSafe5V so the Initial Sink can assume the Power Role of New Source and begin to source VBUS. E When VBUS = vSafe5V the New Source May provide power to VBUS. When VBUS < vSafe5V the New Source Shall provide power to VBUS within tSrcFRSwap. Once the New Source is providing power, the PS_RDY Message can be sent to the New Sink at Step 7 of the messaging sequence. F The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]) before the New Sink sends the PS_RDY Message at Step 5 to the New Source. G The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]) before the New Source sends the PS_RDY Message at Step 7 to the New Sink. Fast Role Swap Message Sequence 1 Policy Engine receives the FR_Swap Message from the Initial Sink that is transitioning to be the New Source. Policy Engine sends the FR_Swap Message to the Initial Source (that is no longer powering VBUS) after detecting the Fast Role Swap Request at Step C. 2 Protocol Layer sends the GoodCRC Message to the Initial Sink. Policy Engine then evaluates the FR_Swap Message. Protocol Layer receives the GoodCRC Message from the Initial Source. 3 Policy Engine sends an Accept Message to the Initial Sink that is transitioning to be the New Source. Policy Engine receives the Accept Message from the Initial Source that is transitioning to be the New Sink. 4 Protocol Layer receives the GoodCRC Message from the Initial Sink that is transitioning to be the New Source. Protocol Layer sends the GoodCRC Message to the Initial Source that is transitioning to be the New Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 403 5 Policy Engine sends a PS_RDY Message to the Initial Sink that is transitioning to be the New Source. The Policy Engine Shall start the PS_RDY Message at least tFRSwap5V after it has sent the Accept Message, and when Step D1 has also been completed. Policy Engine receives the PS_RDY Message from the New Sink. 6 Protocol Layer receives the GoodCRC Message from the New Source. Protocol Layer sends the GoodCRC Message from the Initial Sink that has completed the transition to New Source. Policy Engine then evaluates the PS_RDY Message. 7 Policy Engine receives the PS_RDY Message from the New Source. Policy Engine sends a PS_RDY Message to the New Sink. The Policy Engine Shall wait for Step E before sending the PS_RDY Message, and Shall send the PS_RDY Message within tFRSwapComplete of receiving the PS_RDY Message from the Initial Source Port. Table 7.22 Sequence Description for Fast Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port
7.4 - Electrical Parameters................................................................................................................ (Page 404)
Page 404 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.4 Electrical Parameters 7.4.1 Source Electrical Parameters The Source Electrical Parameters that Shall be followed are specified in Table 7.23, "Source Electrical Parameters". Table 7.23 Source Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSrcBulk Source bulk capacitance when a Port is powered from a dedicated supply.1 10 µF Section 7.1.2 cSrcBulkShared Source bulk capacitance when a Port is powered from a shared supply.1 120 µF Section 7.1.2 DNL (Differential Non- Linearity) Deviation between ideal analog values corresponding to adjacent input digital values -1 0 +1 LSB Section 7.1.4.2.1 iPpsCLMin SPR PPS Minimum Current Limit setting. 1 A Section 7.1.4.2.2 iPpsCLNew Current Limit accuracy Section 7.1.4.2.2 1A ≤ Operating Current ≤ 3A -150 150 mA Operating current > 3A -5 5 % iPpsCLStep SPR PPS Current Limit programming step size (1 LSB). 50 mA Section 7.1.4.2.2 iPpsCLLoadReleaseRate Maximum load decrease slew rate during Current Limit set-point changes. -150 mA/µs Section 7.1.4.2.2 iPpsCLLoadStepRate Maximum load increase slew rate during Current Limit set-point changes. 150 mA/µs Section 7.1.4.2.2 iPpsCLTransient Allowed output current overshoot when a load increase occurs while in CL mode. New load + 100 mA Section 7.1.4.2.2 Allowed output current undershoot when a load decrease occurs while in CL mode. New load – 100 mA 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 405 iPpsCVCLTransient CV to CL transient current bounds assuming the Operating Voltage reduction of Section 7.2.3.1, "Programmable Power Supply Sink Standby". iPpsCLNe w - 100 New load + 500 mA Section 7.1.4.2.2 tAvsTransient The maximum time for the AVS to be between vAvsNew and vAvsValid in response to a load transient. 5 ms Section 7.1.8.4 tAvsSrcTransLarge The time the AVS set- point Shall transition between requested voltages for steps larger than vAvsSmallStep. 0 700 ms Section 7.1.4.3.1 tAvsSrcTransSmall The time the AVS set- point Shall transition between requested voltages for steps smaller than vAvsSmallStep. 0 50 ms Section 7.1.4.3.1 tNewSnk Time allowed for an Initial Source in Swap Standby to transition New Sink operation. 15 ms Section 7.1.10 Figure 7.39 Figure 7.40 tPpsCLCVTransient CL to CV transient voltage settling time. 275 ms Section 7.1.4.2.2 tPpsCLProgramSettle SPR PPS Current Limit programming settling time. 250 ms Section 7.1.4.2.2 tPpsCLSettle CL load transient current settling time. 250 ms Section 7.1.4.2.2 tPpsCVCLTransient CV to CL transient settling time. 250 ms Section 7.1.8.3 tPpsSrcTransLarge The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps larger than vPpsSmallStep. 0 275 ms Section 7.3.1.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 406 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tPpsSrcTransSmall The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps less than or equal to vPpsSmallStep. 0 25 ms Section 7.3.1.3 tPpsTransient The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is greater than or equal to 60mA. 5 ms Section 7.1.8.3 The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8.3 tSrcFRSwap Time from the Initial Sink detecting that VBUS has dropped below vSafe5V until the Initial Sink/new Source is able to supply USB Type-C Current (see [USB Type-C 2.4]) 150 µs Section 7.1.13 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 407 tSrcReady SPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies only to SPR Mode voltage transitions. 285 ms Figure 7.2 Figure 7.3 EPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 720 tSrcRecover SPR Mode Time allotted for the Source to recover. 0.66 1.0 s Section 7.1.5 EPR Mode 1.085 1.425 tSrcSettle SPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vSrcNew. Applies only to SPR Mode voltage transitions. 275 ms Figure 7.2 EPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vAvsNew. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 700 tSrcSwapStdby The maximum time for the Source to transition to Swap Standby. 650 ms Section 7.1.10 Figure 7.17 Figure 7.18 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 408 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tSrcTransient The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is greater or equal to than 60mA. 5 ms Section 7.1.8 The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8 tSrcTransition The time the Source Shall wait before transitioning the power supply to ensure that the Sink has sufficient time to prepare (does not apply to transitions within the same PPS or AVS APDO). 25 35 ms Section 7.3 tSrcTransOff SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the PR_Swap Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 690 ms Section 7.3.2 tSrcTransOn Time from the last bit of the GoodCRC Message acknowledging the PS_RDY Message sent by the new Source, in response to the PR_Swap Message until the PS_RDY Message must be started. 280 ms Section 7.3.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 409 tSrcTransReq SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 325 ms Section 7.3 EPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 760 ms Section 7.3 tSrcTurnOn Transition time from vSafe0V to vSafe5V. 275 ms Figure 7.10 Table 7.20 Table 7.21 vAvsMaxVoltage Maximum Voltage Field in the AVS APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.3.1 vAvsMinVoltage Minimum Voltage Field in the AVS APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.3.1 vAvsNew Adjustable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.4 vAvsSlewNeg AVS maximum slew rate for negative voltage changes. -30 mV/µs Section 7.1.8.4 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 410 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vAvsSlewPos AVS maximum slew rate for positive voltage changes. 30 mV/µs Section 7.1.8.4 vAvsSmallStep AVS step size defined as a small step relative to the previous vAvsNew. -1.0 1.0 V Section 7.1.4.3.1 vAvsStep AVS voltage programming step size. 100 mV Section 7.1.8.4 vAvsValid The range in addition to vAvsNew which the AVS output is considered Valid during and after a transition as well as in response to a transient load condition. -0.5 0.5 V Section 7.1.8.4 vPpsCLCVTransient CL to CV load transient voltage bounds. Operating Voltage * 0.95 – 0.1V Operating Voltage * 1.05 + 0.1V V Section 7.1.4.2.2 vPpsMaxVoltage Maximum Voltage Field in the Programmable Power Supply APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.2.1 vPpsMinVoltage Minimum Voltage Field in the Programmable Power Supply APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.2.1 vPpsNew Programmable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.3 vPpsShutdown The voltage at which the SPR PPS shuts down when operating in CL. APDO Minimum Voltage * 0.85 APDO Minimum Voltage * 0.95 V Section 7.1.4.2.2 vPpsSlewNeg Programmable Power Supply maximum slew rate for negative voltage changes -30 mV/µs Section 7.1.8.3 vPpsSlewPos Programmable Power Supply maximum slew rate for positive voltage changes 30 mV/µs Section 7.1.8.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 411 vPpsSmallStep PPS Step size defined as a small step relative to the previous vPpsNew. -500 500 mV Section 7.1.4.2.2 vPpsStep PPS voltage programming step size (1 LSB). 20 mV Section 7.1.8.3 vPpsValid The range in addition to vPpsNew which the Programmable Power Supply output is considered Valid in response to a load step. -0.1 0.1 V Section 7.1.8.3 vSmallStep VBUS step size increase defined as a small step relative to the previous VBUS when Requesting a different (A)PDO. 500 mV Section 7.1.4.3.1 vSrcNeg Most negative voltage allowed during transition. -0.3 V Figure 7.10 vSrcNew Fixed Supply output measured at the Source receptacle. PDO Voltage *0.95 PDO Voltage PDO Voltage *1.05 V Table 7.2 Variable Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V Battery Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V vSrcPeak The range that a Fixed Supply or EPR AVS in Peak Current operation is allowed when overload conditions occur. PDO Voltage *0.90 PDO Voltage *1.05 V Table 6.10 Table 6.16 Figure 7.14 vSrcSlewNeg Maximum slew rate allowed for negative voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. -30 mV/µs Section 7.1.4.2 Table 7.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 412 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vSrcSlewPos Maximum slew rate allowed for positive voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. 30 mV/µs Section 7.1.4 Figure 7.2 vSrcValid The range in addition to vSrcNew which a newly Negotiated voltage is considered Valid during and after a transition as well as in response to a transient load condition. This range also applies to vSafe5V. -0.5 0.5 V Figure 7.2 Figure 7.3 Section 7.1.8 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 413 7.4.2 Sink Electrical Parameters The Sink Electrical Parameters that Shall be followed are specified in Table 7.24, "Sink Electrical Parameters". Table 7.24 Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSnkBulk Sink bulk capacitance on VBUS at Attach and during FRS after the Initial Source stops sourcing and prior to establishing the First Explicit Contract (see Appendix E, "FRS System Level Example" for an example).1 See [USB 3.2] Section 7.2.2 [USB 3.2] cSnkBulkPd Bulk capacitance on VBUS a Sink is allowed after a successful Negotiation.1 100 µF Section 7.2.2 iLoadReleaseRate Load release di/dt. -150 mA/ µs Section 7.2.6 iLoadStepRate Load step di/dt. 150 mA/ µs Section 7.2.6 iNewFrsSink Maximum current the New Sink can draw during a Fast Role Swap until the New Source applies Rp. Matches the required Fast Role Swap required USB Type-C Current Current field of the Fixed Supply PDO of the Initial Source’s Sink_Capabilities Message. Default USB current or 1.5 or 3.0 A Section 7.1.13 iOvershoot Positive or negative overshoot when a load change occurs less than or equal to iLoadStepRate; relative to the settled value after the load change. -230 230 mA Section 7.2.6 iPpsCLLoadStep Maximum Current set-point change while operating in CL mode. -500 500 mA Section 7.2.3.1 iSafe0mA Maximum current a Sink is allowed to draw when VBUS is driven to vSafe0V. 1.0 mA Figure 7.29 Figure 7.30 iSnkStdby Maximum current during voltage transition. 500 mA Section 7.2.3 iSnkSwapStdby Maximum current a Sink can draw during Swap Standby. Ideally this current is very near to 0 mA largely influenced by Port leakage current. 2.5 mA Section 7.2.7 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Page 414 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 pHubSusp Suspend power consumption for a Hub. 25mW + 25mW per downstream Port for up to 4 ports. 125 mW Section 7.2.3 pSnkSusp Suspend power consumption for a peripheral device. 25 mW Section 7.2.3 tNewSrc Maximum time allowed for an Initial Sink in Swap Standby to transition to New Source operation. 275 ms Section 7.2.7 Table 7.18 Table 7.19 tSnkFRSwap Time during a Fast Role Swap when the New Sink can draw no more than iSnkStdby. 200 µs Section 7.1.13 tSnkHardResetPrepare Time allotted for the Sink power electronics to prepare for a Hard Reset. 15 ms Table 7.12 tSnkNewPower Maximum transition time between power levels. 15 ms Section 7.2.3 tSnkRecover Time for the Sink to resume USB Default Operation. 150 ms Table 7.20 tSnkStdby Time to transition to Sink Standby from Sink. 15 ms Section 7.2.3 tSnkSwapStdby Maximum time for the Sink to transition to Swap Standby. 15 ms Section 7.2.7 vEprMax Highest voltage an EPR Sink is expected to tolerate 55 V Section 7.2.9.2 vSprMax Highest voltage an SPR Sink is expected to tolerate 24 V Section 7.2.9.2 Table 7.24 Sink Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 415 7.4.3 Common Electrical Parameters Electrical Parameters that are common to both the Source and the Sink that Shall be followed are specified in Table 7.25, "Common Source/Sink Electrical Parameters"”. Table 7.25 Common Source/Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference tSafe0V Time to reach vSafe0V max. 650 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tSafe5V Time to reach vSafe5V max. 275 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tVCONNReapplied When the UFP is the VCONN Source: time from the last bit of the GoodCRC acknowledging the PS_RDY Message before reapplying VCONN. When the DFP is the VCONN Source: time from when VCONN drops below vRaReconnect. 10 20 ms Figure 7.19 Figure 7.20 tVCONNValid Time from tVCONNReapplied until VCONN is within vVconnValid (see [USB Type-C 2.4]).1 0 5 ms Figure 7.19 Figure 7.20 tVCONNZero Time from the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message until VCONN is below vRaReconnect (see [USB Type-C 2.4]). 125 ms Figure 7.19 Figure 7.20 vSafe0V Safe operating voltage at “zero volts”. 0 0.8 V Section 7.1.5 vSafe5V Safe operating voltage at 5V. See [USB 2.0] and [USB 3.2] for allowable VBUS voltage range. 4.75 5.5 V Section 7.1.5 1) tVCONNStable (See [USB Type-C 2.4]) still applies.
8 - Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 416)
Page 416 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy 8.1 Overview This section describes the Device Policy and Policy Engine that implements it. For an overview of the architecture and how the Device Policy Manager fits into this architecture, please see Section 2.6, "Architectural Overview".
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Page 416 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy 8.1 Overview This section describes the Device Policy and Policy Engine that implements it. For an overview of the architecture and how the Device Policy Manager fits into this architecture, please see Section 2.6, "Architectural Overview".
8.2 - Device Policy Manager.............................................................................................................. (Page 417)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 417 8.2 Device Policy Manager The Device Policy Manager is responsible for managing the power used by one or more USB Power Delivery ports. In order to have sufficient knowledge to complete this task it needs relevant information about the device it resides in. Firstly, it has a priori knowledge of the device including the Capabilities of the power supply and the receptacles on each Port since these will for example have specific current ratings. It also has to know information from the USB-C® Port Control module regarding cable insertion, type and rating of cable etc. It also has to have information from the power supply about changes in its Capabilities as well as being able to request power supply changes. With all of this information the Device Policy Manager is able to provide up to date information regarding the Capabilities available to a specific Port and to manage the power resources within the device. When working out the Capabilities for a given Source Port the Device Policy Manager will take into account firstly the current rating of the Port's receptacle and whether the inserted cable is PD or non-PD rated and if so, what is the capability of the plug. This will set an upper bound for the Capabilities which might be offered. After this the Device Policy Manager will consider the available power supply resources since this will bound which voltages and currents might be offered. Finally, the Device Policy Manager will consider what power is currently allocated to other ports, which power is in the Power Reserve and any other amendments to Policy from the System Policy Manager. The Device Policy Manager will offer a set of Capabilities within the bounds detailed above. When selecting a capability for a given Sink Port the Device Policy Manager will look at the Capabilities offered by the Source. This will set an upper bound for the Capabilities which might be requested. The Device Policy Manager will also consider which Capabilities are required by the Sink in order to operate. If an appropriate match for voltage and Current can be found within the limits of the receptacle and cable, then this will be requested from the Source. If an appropriate match cannot be found then a request for an offered voltage and current will be made, along with an indication of a Capabilities Mismatch. USB PD defines two types of power sources:  Predefined voltage sources (Fixed Supply, Variable Supply and Battery Supply)  Programmable voltage sources:  Programmable Power Supply (PPS)  Adjustable Voltage Supply (AVS) The first are generally used for classic charging wherein the Charger electronics reside inside the Sink. The Device Policy Manager in the Sink requests a fixed voltage from the list of PDOs offered by the Source and which is converted internally to charge the Sink's Battery and/or power its function. The second moves the Charger electronics that manage the voltage control outside the Sink and back into the Source itself. When in SPR PPS Mode, the Device Policy Manager in the Sink requests a specific voltage with a 20mV accuracy and sets a current limit. Unlike traditional USB where Sinks are responsible for limiting the current, they consume, the SPR PPS Source limits the current to what the Sink has requested. When operating in, the Device Policy Manager in the Sink requests a specific voltage with a 100mV accuracy and requests a maximum current it is allowed to draw. Note: The AVS Sources unlike SPR PPS Sources do not support current limit mode. A Sink operating in is respon- sible not to draw more current than it requests. The process to request power is the same for both types of power Sources although the actual format and contents of the request are slightly different. The primary operational differences are:  A Sink that is using SPR PPS is required to periodically sent requests to let the Source know it is still alive and communicating. When this communication fails a Hard Reset results.  A Sink operating in SPR Mode has no special timing requirements.  A Sink operating in EPR Mode is required to periodically communicate with the Source to let it know it is still operational. If the communication fails, a Hard Reset results. For Dual-Role Power Ports the Device Policy Manager manages the functionality of both a Source and a Sink. In addition, it is able to manage the Power Role Swap process between the two. In terms of power management this Page 418 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 could mean that a Port which is initially consuming power as a Sink is able to become a power resource as a Source. Conversely, Attached Sources might request that power be provided to them. The functionality within the Device Policy Manager (and to a certain extent the Policy Engine) is scalable depending on the complexity of the device, including the number of different power supply Capabilities and the number of different features supported for example System Policy Manager interface or Capabilities Mismatch, and the number of ports being managed. Within these parameters it is possible to implement devices from very simple power supplies to more complex power supplies or devices such as USB Hubs or Hard Drives. Within multi-Port devices it is also permitted to have a combination of USB Power Delivery and non-USB Power Delivery ports which Should all be managed by the Device Policy Manager. As noted in Section 2.6, "Architectural Overview" the logical architecture used in the PD specification will vary depending on the implementation. This means that different implementations of the Device Policy Manager might be relatively small or large depending on the complexity of the device, as indicated above. It is also possible to allocate different responsibilities between the Policy Engine and the Device Policy Manager, which will lead to different types of architectures and interfaces. The Device Policy Manager is responsible for the following:  Maintaining the Local Policy for the device.  For a Source, monitoring the present Capabilities and triggering notifications of the change.  For a Sink, evaluating and responding to Capabilities related requests from the Policy Engine for a given Port.  Control of the Source/Sink in the device.  Control of the USB-C® Port Control module for each Port.  Interface to the Policy Engine for a given Port. The Device Policy Manager is responsible for the following Optional features when implemented:  Communications with the System Policy over USB.  For Sources with multiple ports monitoring and balancing power requirements across these ports.  Monitoring of batteries and AC power supplies.  Managing Modes in its Port Partner and Cable Plug(s). 8.2.1 Capabilities The Device Policy Manager in a Provider Shall know the power supplies available in the device and their Capabilities. In addition, it Shall be aware of any other PD sources of power such as batteries and AC inputs. The available power sources and existing demands on the device Shall be taken into account when presenting Capabilities to a Sink. The Device Policy Manager in a Consumer Shall know the requirements of the Sink and use this to evaluate the Capabilities offered by a Source. It Shall be aware of its own power sources e.g., Batteries or AC supplies where these have a bearing on its operation as a Sink. The Device Policy Manager in a Dual-Role Power Device Shall combine the above Capabilities and Shall also be able to present the dual-role nature of the device to an Attached PD Capable device. 8.2.2 System Policy A given PD Capable device might have no USB capability, or PD might have been added to a USB device in such a way that PD is not integrated with USB. In these two cases there Shall be no requirement for the Device Policy Manager to interact with the USB interface of the device. The following requirements Shall only apply to PD devices that expose PD functionality over USB. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 419 The Device Policy Manager Shall communicate over USB with the System Policy Manager according to the requirements detailed in [UCSI]. Whenever requested the Device Policy Manager Shall implement a Local Policy according to that requested by the System Policy Manager. For example, the System Policy Manager might request that a Battery powered Device temporarily stops charging so that there is sufficient power for an HDD to spin up. Note: Due to timing constraints, a PD Capable device Shall be able to respond autonomously to all time-critical PD related requests. 8.2.3 Control of Source/Sink The Device Policy Manager for a Provider Shall manage the power supply for each PD Source Port and Shall know at any given time what the Negotiated power is. It Shall request transitions of the supply and inform the Policy Engine whenever a transition completes. The Device Policy Manager for a Consumer Shall manage the Sink for each PD Sink Port and Shall know at any given time what the Negotiated power is. The Device Policy Manager for a Dual-Role Power Device Shall manage the transition between Source/Sink Power Roles for each PD Dual-Role Power Port and Shall know at any given time what Power Role the Port is in. 8.2.4 Cable Detection 8.2.4.1 Device Policy Manager in a Provider The Device Policy Manager in the Provider Shall control the USB-C® Port Control module and Shall be able to use the USB-C® Port Control module to determine the Attachment status. Note: It might be necessary for the Device Policy Manager to also initiate additional discovery using the Discov- er Identity Command in order to determine the full Capabilities of the cabling (see Section 6.4.4.3.1, "Dis- cover Identity"). 8.2.4.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer controls the USB-C® Port Control module and Shall be able to use the USB- C® Port Control module to determine the Attachment status. 8.2.4.3 Device Policy Manager in a Consumer/Provider The Device Policy Manager in a Consumer/Provider inherits characteristics of Consumers and Providers and Shall control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Attachment of a USB Power Delivery Provider/Consumer which supports Dead Battery back-powering.  Presence of VBUS. 8.2.4.4 Device Policy Manager in a Provider/Consumer The Device Policy Manager in a Provider/Consumer inherits characteristics of Consumers and Providers and May control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Presence of VBUS. Page 420 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.2.5 Managing Power Requirements It is the responsibility of the Device Policy Manager in a Provider to be aware of the power requirements of all devices connected to its Source Ports. This includes being aware of any reserve power that might be required by devices in the future and ensuring that power is shared optimally amongst Attached PD Capable devices. This is a key function of the Device Policy Manager; whose implementation is critical to ensuring that all PD Capable devices get the power they require in a timely fashion in order to facilitate smooth operation. This is balanced by the fact that the Device Policy Manager is responsible for managing the sources of power that are, by definition, finite. The Consumer's Device Policy Manager Shall ensure that it takes no more power than is required to perform its functions and when its requirements change, it Should make a new Request. The Provider, after satisfying the Request, Should reclaim any unused power to ensure that it can meet total power requirements of Attached Sinks on at least one Port. Note: It is expected that a future design guide will provide additional guidance. 8.2.5.1 Managing the Power Reserve There might be some products where a Device has certain functionality at one power level and a greater functionality at another, for example a Printer/Scanner that operates only as a printer with one power level and as a scanner if it can get more power. While the visibility of the linkage between power and functionality might only be apparent to the USB Host; the Device Policy Manager Should provide mechanisms to manage the power requirements of such Devices. It is the Device Policy Manager's responsibility to allocate power and maintain a power reserve so as not to over- subscribe its available power resource. A Device with multiple ports such as a Hub Shall always attempt to meet the incremental demands of the Port requiring the highest incremental power from its power reserve. 8.2.5.2 Power Capability Mismatch A Capabilities Mismatch occurs when a Consumer cannot obtain required power from a Provider (or the Source is not PD Capable) and the Consumer requires such Capabilities to operate. Different actions are taken by the Device Policy Manager and the System Policy Manager in this case. 8.2.5.2.1 Local device handling of mismatch The Consumer's Device Policy Manager Shall cause a notification to be displayed to the end user that a power Capabilities Mismatch has occurred. Examples of such feedback can include:  For a simple Device an LED May be used to indicate the failure. For example, during connection the LED could be solid amber. If the connection is successful, the LED could change to green. If the connection fails, it could be red or alternately blink amber.  A more sophisticated Device with a user interface, e.g., a mobile device or monitor, Should provide no- tification through the user interface on the Device. The Provider's Device Policy Manager May cause a notification to be displayed to the user of the power Capabilities Mismatch. Because the Capabilities Mismatch might not cause operational failure, the Provider's Device Policy Manager Should Not display a notification to the user if the power offered to the Sink meets or exceeds the SPR Sink Minimum PDP/ EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). If a notification is displayed, it Should Not be shown as an error unless the power offered to the Sink is less than the SPR Sink Minimum PDP/EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message. 8.2.5.2.2 Device Policy Manager Communication with System Policy In a USB Power Delivery aware system with an active System Policy Manager (see Section 8.2.2, "System Policy"), the Device Policy Manager Shall notify the System Policy Manager of the mismatch. This information Shall be passed back to the System Policy Manager using the mechanisms described in [UCSI]. The System Policy Manager Should Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 421 ensure that the user is informed of the condition. When another Port in the system could satisfy the Consumer's power requirements the user Should be directed to move the Device to the alternate Port. In order to identify a more suitable Source Port for the Consumer the System Policy Manager Shall communicate with the Device Policy Manager in order to determine the Consumer's requirements. The Device Policy Manager Shall use a Get_Sink_Cap Message (see Section 6.3.8, "Get_Sink_Cap Message") to discover which power levels can be utilized by the Consumer. 8.2.6 Use of "Unconstrained Power" bit with Batteries and AC supplies The Device Policy Manager in a Provider or Consumer May monitor the status of any variable sources of power that could have an impact on its Capabilities as a Source such as Batteries and AC supplies and reflect this in the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") provided as part of the Source_Capabilities or Sink_Capabilities Message (see Section 6.4.1, "Capabilities Message"). When monitored, and a USB interface is supported, the External Power status (see [UCSI]) and the Battery state (see Section 9.4.1, "GetBatteryStatus") Shall also be reported to the System Policy Manager using the USB interface. 8.2.6.1 AC Supplies The Unconstrained Power bit provided by Sources and Sinks (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") notifies a connected device that it is acceptable to use the Advertised power for charging as well as for what is needed for normal operation. A device that sets the Unconstrained Power bit has either an external source of power that is sufficient to adequately power the system while charging external devices or expects to charge external devices as a primary state of function (such as a battery pack). In the case of the external power source, the power can either be from an AC Supply directly connected to the device or from an AC Supply connected to an Attached device, which is also getting unconstrained power from its power supply. The Unconstrained Power bit is in this way communicated through a PD system indicating that the origin of the power is from a single or multiple AC supplies, from a battery bank, or similar:  If the "Unconstrained Power" bit is set, then that power is originally sourced from an AC Supply.  Devices capable of consuming on multiple ports can only claim that they have "Unconstrained Power" for the power Advertised as a Provider Port if there is unconstrained power beyond that needed for nor- mal operation coming from external supplies, (e.g., multiple AC supplies).  This concept applies as the power is routed through multiple Provider and Consumer tiers, so, as an ex- ample. Power provided out of a monitor that is connected to a monitor that gets power from an AC Sup- ply, will claim it has "Unconstrained Power" even though it is not directly connected to the AC Supply. An example use case is a Tablet computer that is used with two USB A/V displays that are daisy chained (see Figure 8.1, "Example of daisy chained displays"). The tablet and 1st display are not externally powered, (meaning, they have no source of power outside of USB PD). The 2nd display has an external supply Attached which could either be a USB PD based supply or some other form of external supply. When the displays are connected as shown, the power adapter Attached to the 2nd display is able to power both the 1st display and the tablet. In this case the 2nd display will indicate the presence of a sufficiently sized Charger to the 1st display, by setting its "Unconstrained Power" bit. The 1st display will then in turn assess and indicate the presence of the extra power to the tablet by setting its "Unconstrained Power" bit. Power is transmitted through the system to all devices, provided that there is sufficient power available from the external supply. Page 422 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.1 Example of daisy chained displays Another example use case is a laptop computer that is Attached to both an external supply and a Tablet computer. In this situation, if the external supply is large enough to power the laptop in its normal state as well as charge an external device, the laptop would set its "Unconstrained Power" bit and the tablet will allow itself to charge at its peak rate. If the external supply is small, however, and would not prevent the laptop from discharging if maximal power is drawn by the external device, the laptop would not set its "Unconstrained Power" bit, and the tablet can choose to draw less than what is offered. This amount could be just enough to prevent the tablet from discharging, or none at all. Alternatively, if the tablet determines that the laptop has significantly larger battery with more charge than the tablet has, the tablet can still choose to charge itself, although possibly not at the maximal rate. In this way, Sinks that do not receive the Unconstrained Power bit from the connected Source can still choose to charge their batteries, or charge at a reduced rate, if their policy determines that the impact to the Source is minimal -- such as in the case of a phone with a small battery charging from a laptop with a large battery. These policies can be decided via further USB PD communication. 8.2.6.2 Battery Supplies When monitored, and a USB interface is supported, the Battery state Shall be reported to the System Policy Manager using the USB interface. If the device is Battery-powered but is in a state that is primarily for charging external devices, the device is considered to be an unconstrained source of power and thus Should set the "Unconstrained Power" bit. A simplified algorithm is detailed below to ensure that Battery powered devices will get charge from non-Battery powered devices when possible, and also to ensure that devices do not constantly Power Role Swap back and forth. When two devices are connected that do not have Unconstrained Power, they Should define their own policies so as to prevent constant Power Role Swapping. This algorithm uses the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power"), thus the decisions are based on the availability and sufficiency of an external supply, not the full Capabilities of a system or device or product. Recommendations:  Provider/Consumers using large external sources ("Unconstrained Power" bit set) Should always deny Power Role Swap requests from Consumer/Providers not using external sources ("Unconstrained Pow- er" bit cleared). AC Tablet Display 1 Display 2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 423  Provider/Consumers not using large external sources ("Unconstrained Powered" bit cleared) Should al- ways accept a Power Role Swap request from a Consumer/Provider using large external power sources ("Unconstrained Power" bit set) unless the requester is not able to provide the requirements of the present Provider/Consumer. 8.2.7 Interface to the Policy Engine The Device Policy Manager Shall maintain an interface to the Policy Engine for each Port in the device. 8.2.7.1 Device Policy Manager in a Provider The Device Policy Manager in a Provider Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/ device Attachment status for a given cable.  Inform the Policy Engine whenever the Source Capabilities available for a Port change.  Evaluate requests from an Attached Consumer and provide responses to the Policy Engine.  Respond to requests for power supply transitions from the Policy Engine.  Indication to Policy Engine when power supply transitions are complete.  Maintain a power reserve for devices operating on a Port at less than maximum power. 8.2.7.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/device Attachment status.  Inform the Policy Engine whenever the power requirements for a Port change.  Evaluate Source Capabilities and provide suitable responses:  Request from offered Capabilities.  Indicate whether additional power is required.  Respond to requests for Sink transitions from the Policy Engine. 8.2.7.3 Device Policy Manager in a Dual-Role Power Device The Device Policy Manager in a Dual-Role Power Device Shall provide the following functions to the Policy Engine:  Provider Device Policy Manager  Consumer Device Policy Manager  Interface for the Policy Engine to request power supply transitions from Source to Sink and vice versa.  Indications to Policy Engine during Power Role Swap transitions. 8.2.7.4 Device Policy Manager in a Dual-Role Power Device Dead Bat- tery handling The Device Policy Manager in a Dual-Role Power Device with a Dead Battery Should:  Switch Ports to Sink-only or Sink DFP operation to obtain power from the next Attached Source.  Use VBUS from the Attached Source to power the USB Power Delivery communications as well as charging to enable the Negotiation of higher input power.
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Page 424 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3 Policy Engine 8.3.1 Introduction There is one Policy Engine instance per Port that interacts with the Device Policy Manager in order to implement the present Local Policy for that particular Port. This section includes:  AMSs for various operations.  State diagrams covering operation of Sources, Sinks and Cable Plugs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 425 8.3.2 Atomic Message Sequence Diagrams 8.3.2.1 Introduction The Policy Engine drives the Atomic Message Sequences (AMS) and responses based on both the expected AMSs and the present Local Policy. An AMS Shall be defined as a Message sequence that starts and/or ends in either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states (see Section 8.3.3.2, "Policy Engine Source Port State Diagram", Section 8.3.3.3, "Policy Engine Sink Port State Diagram" and Section 8.3.3.25, "Cable Plug Specific State Diagrams"). In addition, the Cable Plug discovery sequence specified in Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram" Shall be defined as an AMS. The Source and Sink indicate to the Protocol Layer when an AMS starts and ends on entry to/exit from PE_SRC_Ready or PE_SNK_Ready (see Section 8.3.3.2, "Policy Engine Source Port State Diagram" and Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). An AMS Shall be considered to have been started by the Initiator when the protocol engine signals the Policy Engine that transmission is a success (the GoodCRC Message has been received in response to the initial Message). For the receiving Port the AMS Shall be considered to have started when the initial Message has arrived. An AMS Shall be considered to have ended:  When the Protocol Layer signals the Policy Engine that transmission of the final Message in the AMS is a success and for the opposite Port when the final Message has been received.  A Soft_Reset Message, Hard Reset Signaling for SOP’ or SOP’’ or Cable Reset Signaling has been sent or received. Section 8.3.2.1.3, "Atomic Message Sequences" gives details of these AMS's. This section contains sequence diagrams that highlight some of the more interesting transactions. It is by no means a complete summary of all possible combinations but is Informative in nature. Page 426 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.1 Basic Message Exchange Figure 8.2, "Basic Message Exchange (Successful)" below illustrates how a Message is sent. Table 8.1, "Basic Message Flow" details the steps in the flow. Note that the sender might be either a Source or Sink while the receiver might be either a Sink or Source. The basic Message sequence is the same. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. Figure 8.2 Basic Message Exchange (Successful) Table 8.1 Basic Message Flow Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 7 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Protocol Layer checks and increments the MessageIDCounter and stops CRCReceiveTimer. 9 Protocol Layer informs the Policy Engine that the Message was successfully sent. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 427 8.3.2.1.2 Errors in Basic Message flow There are various points during the Message flow where failures in communication or other issues can occur. Figure 8.3, "Basic Message flow indicating possible errors" is an annotated version of Figure 8.2, "Basic Message Exchange (Successful)" indicating at which point issues can occur. Table 8.2, "Potential issues in Basic Message Flow" details the steps in the flow. Figure 8.3 Basic Message flow indicating possible errors Table 8.2 Potential issues in Basic Message Flow Point Possible issues A 1) There is an incoming Message on the channel meaning that the PHY Layer is unable to send. In this case the outgoing Message is removed from the queue and the incoming Message processed. 2) Due to some sort of noise on the line it is not possible to transmit. In this case the outgoing Message is Discarded by the PHY Layer. Retransmission is via the Protocol Layer’s normal mechanism. B 1) Message does not arrive at the PHY Layer due to noise on the channel. 2) Message arrives but has been corrupted and has a bad CRC. There is no Message to pass up to the Protocol Layer on the receiver which means a GoodCRC Message is not sent. This leads to a CRCReceiveTimer timeout in the Message Sender. C 1) MessageID of received Message matches stored MessageID so this is a retry. Message is not passed up to the Policy Engine. D 1) Policy Engine receives a known Message that it was not expecting. 2) Policy Engine receives an Unrecognized Message. These cases are errors in the protocol which could lead to the generation of a Soft_Reset Message. E Same as point A but at the Message Receiver side. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver • Message currently being received • Channel unavailable • Message does not arrive • Message has bad CRC • Message is a retry • Message is unexpected • Message is unknown • Message currently being received • Channel unavailable • GoodCRC does not arrive • GoodCRC has a bad CRC • GoodCRC has the wrong MessageID • Response is not GoodCRC A B C D E F G Page 428 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.4, "Basic Message Flow with Bad followed by a Retry" illustrates one of these cases; the basic Message flow with a retry due to a bad CRC at the Message Receiver. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. The Protocol Layer is responsible for retries on a “'n' strikes and you are out" basis (nRetryCount). Table 8.3, "Basic Message Flow with CRC failure" details the steps in the flow. Figure 8.4 Basic Message Flow with Bad followed by a Retry F 1) GoodCRC Message response does not arrive at the Message Sender side due to the noise on the channel. 2) GoodCRC Message response arrives but has a bad CRC. A GoodCRC Message is not received by the Message Sender’s Protocol Layer. This leads to a CRCReceiveTimer timeout in the Message Sender. G 1) GoodCRC Message is received but does contain the same MessageID as the transmitted Message. 2) A Message is received but it is not a GoodCRC Message (similar case to that of an unexpected or unknown Message but this time detected in the Protocol Layer). Both of these issues indicate errors in receiving an expected GoodCRC Message which will lead to a CRCReceiveTimer timeout in the Protocol Layer and a subsequent retry (except for communications with Cable Plugs). Table 8.2 Potential issues in Basic Message Flow Point Possible issues : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine 4: Message 5: Message + CRC 6: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 7: Message received Consume message 8: GoodCRC 9: GoodCRC + CRC 10: GoodCRC Check and increment MessageIDCounter Reset RetryCounter Stop CRCReceiveTimer 11: Message sent 1: Send message 2: Message 3: Message + CRC Start CRCReceiveTimer CRCReceiveTimer expires Retry and increment RetryCounter Message is not received or CRC is bad so message is not passed to the protocol layer Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 429 Table 8.3 Basic Message Flow with CRC failure Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives no Message or a Message with an incorrect CRC. Nothing is passed to Protocol Layer. 4 Since no response is received, the CRCReceiveTimer will expire and trigger the first retry by the Protocol Layer. The RetryCounter is incremented. Protocol Layer passes the Message to the PHY Layer. 5 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 6 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 7 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 8 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 9 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 10 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 11 Protocol Layer verifies the MessageID, stops CRCReceiveTimer and resets the RetryCounter. Protocol Layer informs the Policy Engine that the Message was successfully sent. Page 430 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3 Atomic Message Sequences The types of Atomic Message Sequences (AMS) are listed in Table 8.4, "Atomic Message Sequences". The following tables list sequences of either Messages or combinations of Messages and one or more embedded AMSes which are Non-interruptible. Where there is an embedded AMS the entire Message sequence is treated as an AMS and the Rp value used for Collision Avoidance (see Section 5.7, "Collision Avoidance") Shall only be changed on leaving or entering the ready state at the beginning or end of the entire Message sequence, and not at the start or end of the embedded AMS. Note: An AMS is has not started until the first Message in the sequence has been successfully sent (i.e., a GoodCRC Message has been received acknowledging the Message). Table 8.31, "AMS: Hard Reset" details a Hard Reset (which is Signaling not an AMS) followed by an SPR Contract Negotiation AMS which Shall be treated as Non-interruptible. Table 8.4 Atomic Message Sequences Type of AMS Table Reference Section Reference Power Negotiation (SPR) Table 8.5, "AMS: Power Negotiation (SPR)" Section 8.3.2.2.1 Power Negotiation (EPR) Table 8.6, "AMS: Power Negotiation (EPR)" Section 8.3.2.2.2 Unsupported Message Table 8.7, "AMS: Unsupported Message" Section 8.3.2.3 Soft Reset Table 8.8, "AMS: Soft Reset" Section 8.3.2.4 Data Reset Table 8.9, "AMS: Data Reset" Section 8.3.2.5 Hard Reset Table 8.31, "AMS: Hard Reset" Section 8.3.2.6 Power Role Swap Table 8.10, "AMS: Power Role Swap" Section 8.3.2.7 Fast Role Swap Table 8.11, "AMS: Fast Role Swap" Section 8.3.2.8 Data Role Swap Table 8.12, "AMS: Data Role Swap" Section 8.3.2.9 VCONN Swap Table 8.13, "AMS: VCONN Swap" Section 8.3.2.10 Alert Table 8.14, "AMS: Alert" Section 8.3.2.11.1 Status Table 8.15, "AMS: Status" Section 8.3.2.11.2 Source Capabilities/ Sink Capabilities (SPR) Table 8.16, "AMS: Source/Sink Capabilities (SPR)" Section 8.3.2.11.3.1 Source Capabilities/ Sink Capabilities (EPR) Table 8.17, "AMS: Source/Sink Capabilities (EPR)" Section 8.3.2.11.3.2 Extended Capabilities Table 8.18, "AMS: Extended Capabilities" Section 8.3.2.11.4 Battery Capabilities and Status Table 8.19, "AMS: Battery Capabilities" Section 8.3.2.11.5 Manufacturer Information Table 8.20, "AMS: Manufacturer Information" Section 8.3.2.11.6 Country Codes Table 8.21, "AMS: Country Codes" Section 8.3.2.11.7 Country Information Table 8.22, "AMS: Country Information" Section 8.3.2.11.8 Revision Information Table 8.23, "AMS: Revision Information" Section 8.3.2.11.9 Source Information Table 8.24, "AMS: Source Information" Section 8.3.2.11.10 Security Table 8.25, "AMS: Security" Section 8.3.2.12 Firmware Update Table 8.26, "AMS: Firmware Update" Section 8.3.2.13 Structured VDM Table 8.27, "AMS: Structured VDM" Section 8.3.2.14 Built-In Self-Test (BIST) Table 8.28, "AMS: Built-In Self-Test (BIST)" Section 8.3.2.15 Enter USB Table 8.29, "AMS: Enter USB" Section 8.3.2.16 Unstructured VDM Table 8.30, "AMS: Unstructured VDM" Section 8.3.2.17 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 431 8.3.2.1.3.1 AMS: Power Negotiation (SPR) Table 8.5 AMS: Power Negotiation (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref SPR Explicit Contract Negotiation (Accept) 1. Source_Capabilities Message 2. Request Message 3. Accept Message 4. PS_RDY Message Started by Source, SPR Mode Section 8.3.2.2.1.1.1 Section 8.3.3.2, Section 8.3.3.3 SPR Explicit Contract Negotiation (Reject) 1. Source_Capabilities Message 2. Request Message 3. Reject Message Section 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Wait) 1. Source_Capabilities Message 2. Request Message 3. Wait Message Section 8.3.2.2.1.1.3 SPR PPS Keep Alive 1. Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, SPR Mode Section 8.3.2.2.1.2 Section 8.3.3.3 SPR Sink Makes Request (Accept) 1. Request Message 2. Accept Message 3. PS_RDY Message Section 8.3.2.2.1.3.1 Section 8.3.3.2, Section 8.3.3.3 SPR Sink Makes Request (Reject) 1. Request Message 2. Reject Message Section 8.3.2.2.1.3.2 SPR Sink Makes Request (Wait) 1. Request Message 2. Wait Message Section 8.3.2.2.1.3.3 Page 432 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.2 AMS: Power Negotiation (EPR) Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Entering EPR Mode (Success) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS (Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Succeeded) Message 6. EPR Explicit Contract Negotiation AMS Started by Sink, SPR Mode Section 8.3.2.2.2.1, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3, Section 8.3.2.2.2.4 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1, Section 8.3.3.2, Section 8.3.3.3 Entering EPR Mode (Failure due to non-EPR Cable) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS(Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.2, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1 Entering EPR Mode (Failure of VCONN Swap) 1. EPR_Mode (Enter) Message. 2. EPR_Mode (Enter Acknowledge) Message. 3. VCONN Source Swap, initiated by non- VCONN Source (Reject) AMS(Optional). 4. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.3, Section 8.3.2.10.1, Section 8.3.2.10.2 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 433 EPR Explicit Contract Negotiation (Accept) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Accept Message 4. PS_RDY Message Started by Source, EPR Mode Section 8.3.2.2.2.2.1 Section 8.3.3.2, Section 8.3.3.3 EPR Explicit Contract Negotiation (Reject) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Reject Message Section 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Wait) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Wait Message Section 8.3.2.2.2.2.3 EPR Keep Alive 1. EPR_KeepAlive Message 2. EPR_KeepAlive_Ack Message Started by Sink, EPR Mode Section 8.3.2.2.2.3 Exiting EPR Mode (Sink Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Sink, EPR Mode Section 8.3.2.2.2.4.1, Section 8.3.2.2.1.1 Section 8.3.3.25.3, Section 8.3.3.25.4, Section 8.3.3.2, Section 8.3.3.3 Exiting EPR Mode (Source Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Source, EPR Mode Section 8.3.2.2.2.4.2, Section 8.3.2.2.1.1 EPR Sink Makes Request (Accept) 1. EPR_Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.1 Section 8.3.3.2, Section 8.3.3.3 EPR Sink Makes Request (Reject) 1. EPR_Request Message 2. Reject Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.2 EPR Sink Makes Request (Wait) 1. EPR_Request Message 2. Wait Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.3 Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Page 434 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.3 AMS: Unsupported Message 8.3.2.1.3.4 AMS: Soft Reset 8.3.2.1.3.5 AMS: Data Reset Table 8.7 AMS: Unsupported Message AMS Message Sequence Conditions AMS Ref State Machine Ref Unsupported Message 1. Any Message which is not supported by the Source or Sink 2. Not_Supported Message Started by Source or Sink Section 8.3.2.3 Section 8.3.3.6.2 Table 8.8 AMS: Soft Reset AMS Message Sequence Conditions AMS Ref State Machine Ref Soft Reset 1. Soft_Reset Message 2. Accept Message 3. In SPR Mode: SPR Explicit Contract Negotiation AMS 4. or in EPR Mode: EPR Explicit Contract Negotiation AMS. Started by Source or Sink Section 8.3.2.4, Section 8.3.2.2.1.1, Section 8.3.2.2.1.1, Section 8.3.2.2.2.2 Section 8.3.3.4.1, Section 8.3.3.4.2, Section 8.3.3.25.2.1, Section 8.3.3.25.2.3, Section 8.3.3.25.2.4, Section 8.3.3.2, Section 8.3.3.3 Table 8.9 AMS: Data Reset AMS Message Sequence Conditions AMS Ref State Machine Ref DFP Initiated Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.1 Section 8.3.3.5.1, Section 8.3.3.5.2 DFP Receives Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.2 DFP Initiated Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.3 DFP Receives Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 435 8.3.2.1.3.6 AMS: Power Role Swap 8.3.2.1.3.7 AMS: Fast Role Swap Table 8.10 AMS: Power Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.7.1.1, Section 8.3.2.2.1.1 Section 8.3.3.19.3, Section 8.3.3.19.4, Section 8.3.3.2, Section 8.3.3.3 Source Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.1.2 Source Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.1.1 Sink Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.7.2.1, Section 8.3.2.2.1.1 Sink Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.2.2 Sink Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.2.3 Table 8.11 AMS: Fast Role Swap AMS Message Sequence Conditio ns AMS Ref State Machine Ref Fast Role Swap 1. FR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.8, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3, Section 8.3.3.19.5, Section 8.3.3.19.6 Page 436 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.8 AMS: Data Role Swap Table 8.12 AMS: Data Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Data Role Swap, Initiated by UFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.1.1 Section 8.3.3.19.1, Section 8.3.3.19.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.2.3 Data Role Swap, Initiated by DFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.4.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 437 8.3.2.1.3.9 AMS: VCONN Swap 8.3.2.1.3.10 AMS: Alert Table 8.13 AMS: VCONN Swap AMS Message Sequence Conditions AMS Ref State Machine Ref VCONN Source Swap, initiated by VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by VCONN Source Section 8.3.2.10.1.1 Section 8.3.3.20 VCONN Source Swap, initiated by VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.1.3 VCONN Source Swap, initiated by non- VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by non-VCONN Source Section 8.3.2.10.2.1 VCONN Source Swap, initiated by non- VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.2.2 VCONN Source Swap, initiated by non- VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.2.3 Table 8.14 AMS: Alert AMS Message Sequence Conditions AMS Ref AMS Ref Source sends Alert to a Sink (SenderResponseTi mer Timeout) 1. Alert Message Started by Source Section 8.3.2.11.1.1 Section 8.3.3.7.1, Section 8.3.3.7.2 Source sends Alert to a Sink (Get_Status Message) 1. Alert Message 2. Sink Gets Source Status AMS Sink sends Alert to a Source (SenderResponseTi mer Timeout) 1. Alert Message Started by Sink Section 8.3.2.11.1.2 Section 8.3.3.7.3, Section 8.3.3.7.4 Sink sends Alert to a Source (Get_Status Message) 1. Alert Message 2. Source Gets Sink Status AMS Page 438 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.11 AMS: Status 8.3.2.1.3.12 AMS: Source/Sink Capabilities (SPR) Table 8.15 AMS: Status AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Status 1. Get_Status Message 2. Status Message Started by Sink Started by Source Section 8.3.2.11.2.1, Section 8.3.2.11.2.2 Section 8.3.3.10.1, Section 8.3.3.10.2 Source Gets Sink Status 1. Get_Status Message 2. Status Message VCONN Source Gets Cable Plug Status 1. Get_Status Message 2. Status Message Started by VCONN Source Started by Sink Section 8.3.2.11.2.3, Section 8.3.2.11.2.4 Sink Gets Source PPS Status 1. Get_PPS_Status Message 2. PPS_Status Message Section 8.3.3.10.3, Section 8.3.3.10.4 Table 8.16 AMS: Source/Sink Capabilities (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Capabilities (EPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Sink Section 8.3.2.11.3.1.1, Section 8.3.2.2.1.3.1, Section 8.3.2.2.1.3.2, Section 8.3.2.2.1.3.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets Source Capabilities (Accept in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Accept) AMS Sink Gets Source Capabilities (Reject in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Reject) AMS Sink Gets Source Capabilities (Wait in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Source Section 8.3.2.11.3.1.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink Capabilities 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Source Section 8.3.2.11.3.1.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.1.4 Section 8.3.3.19.9, Section 8.3.3.19.8 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 439 8.3.2.1.3.13 AMS: Source/Sink Capabilities (EPR) Table 8.17 AMS: Source/Sink Capabilities (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets EPR Source Capabilities (SPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Sink Section 8.3.2.11.3.2.1, Section 8.3.2.2.2.5.1, Section 8.3.2.2.2.5.2, Section 8.3.2.2.2.5.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets EPR Source Capabilities (Accept in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Accept) AMS Sink Gets EPR Source Capabilities (Reject in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Reject) AMS Sink Gets EPR Source Capabilities (Wait in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power EPR Sink 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Source Section 8.3.2.11.3.2.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink EPR Capabilities 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Source Section 8.3.2.11.3.2.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink EPR Capabilities from a Dual-Role Power Source 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.2.4 Section 8.3.3.19.8, Section 8.3.3.19.9 Page 440 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.14 AMS: Extended Capabilities 8.3.2.1.3.15 AMS: Battery Capabilities Table 8.18 AMS: Extended Capabilities AMS Interruptible Message Sequence Conditions AMS Ref Sink Gets Source Extended Capabilities 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.4.1 Section 8.3.3.8.1, Section 8.3.3.8.2 Dual-Role Power Source Gets Source Extended Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.4.2 Section 8.3.3.19.11, Section 8.3.3.19.12 Source Gets Sink Extended Capabilities 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Source Section 8.3.2.11.4.3 Section 8.3.3.8.3, Section 8.3.3.8.4 Dual-Role Power Sink Gets Sink Extended Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Sink Section 8.3.2.11.4.4 Section 8.3.3.19.13, Section 8.3.3.19.14 Table 8.19 AMS: Battery Capabilities AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Sink Section 8.3.2.11.5.1 Section 8.3.3.11.1, Section 8.3.3.11.2 Source Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Source Section 8.3.2.11.5.2 Sink Gets Battery Status 1. Get_Battery_Status Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.3 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Battery Status 1. Get_Battery_Cap Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 441 8.3.2.1.3.16 AMS: Manufacturer Information 8.3.2.1.3.17 AMS: Country Codes 8.3.2.1.3.18 AMS: Country Information Table 8.20 AMS: Manufacturer Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Port Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.1 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Port Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.2 Source Gets Battery Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.3 Sink Gets Battery Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.4 VCONN Source Gets Manufacturer Information from a Cable Plug 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by VCONN Source Section 8.3.2.11.6.5 Table 8.21 AMS: Country Codes AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Codes from a Sink 1. Get_Country_Codes Message 2. Country_Codes Message Started by Source Section 8.3.2.11.7.1 Section 8.3.3.14.1, Section 8.3.3.14.2 Sink Gets Country Codes from a Source 1. Get_Country_Codes Message 2. Country_Codes Message Started by Sink Section 8.3.2.11.7.2 VCONN Source Gets Country Codes from a Cable Plug 1. Get_Country_Codes Message 2. Country_Codes Message Started by VCONN Source Section 8.3.2.11.7.3 Table 8.22 AMS: Country Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Information from a Sink 1. Get_Country_Info Message 2. Country_Info Message Started by Source Section 8.3.2.11.8.1 Section 8.3.3.14.3, Section 8.3.3.14.4 Sink Gets Country Information from a Source 1. Get_Country_Info Message 2. Country_Info Message Started by Sink Section 8.3.2.11.8.2 VCONN Source Gets Country Information from a Cable Plug 1. Get_Country_Info Message 2. Country_Info Message Started by VCONN Source Section 8.3.2.11.8.3 Page 442 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.19 AMS: Revision Information 8.3.2.1.3.20 AMS: Source Information 8.3.2.1.3.21 AMS: Security Table 8.23 AMS: Revision Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Revision Information from a Sink 1. Get_Revision Message 2. Revision Message Started by Source Section 8.3.2.11.9.1 Section 8.3.3.15.1, Section 8.3.3.15.2 Sink Gets Revision Information from a Source 1. Get_Revision Message 2. Revision Message Started by Sink Section 8.3.2.11.9.2 VCONN Source Gets Revision Information from a Cable Plug 1. Get_Revision Message 2. Revision Message Started by VCONN Source Section 8.3.2.11.9.1 Table 8.24 AMS: Source Information AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Information 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.10.1 Section 8.3.3.9.1, Section 8.3.3.9.2 Dual-Role Power Source Gets Source Information from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.10.2 Section 8.3.3.19.15, Section 8.3.3.19.16 Table 8.25 AMS: Security AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests security exchange with Sink 1. Security_Request Message Started by Source Section 8.3.2.12.1 Section 8.3.3.17.1, Section 8.3.3.17.2, Section 8.3.3.17.3 Sink requests security exchange with Source 1. Security_Request Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Request Message Started by VCONN Source Section 8.3.2.12.3 Source responds to security exchange with Sink 1. Security_Response Message Started by Source Section 8.3.2.12.1 Sink responds to security exchange with Source 1. Security_Response Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Response Message Started by VCONN Source Section 8.3.2.12.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 443 8.3.2.1.3.22 AMS: Firmware Update Table 8.26 AMS: Firmware Update AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests firmware update exchange with Sink 1. Firmware_Update_Request Message Started by Source Section 8.3.2.13.1 Section 8.3.3.18.1, Section 8.3.3.18.2, Section 8.3.3.18.3 Sink requests firmware update exchange with Source 1. Firmware_Update_Request Message Started by Sink Section 8.3.2.13.2 VCONN Source requests firmware update exchange with Cable Plug 1. Firmware_Update_Request Message Started by VCONN Source Section 8.3.2.13.3 Source responds to firmware update exchange with Sink 1. Firmware_Update_Response Message Started by Source Section 8.3.2.13.1 Sink responds to firmware update exchange with Source 1. Firmware_Update_Response Message Started by Sink Section 8.3.2.13.2 VCONN Source responds to firmware update exchange with Cable Plug 1. Firmware_Update_Response Message Started by VCONN Source Section 8.3.2.13.3 Page 444 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.23 AMS: Structured VDM Table 8.27 AMS: Structured VDM AMS Message Sequence Conditions AMS Ref State Machine Ref Initiator to Responder Discover Identity (ACK) 1. Discover Identity REQ Command 2. Discover Identity ACK Command Started by Initiator Section 8.3.2.14.1.1 Section 8.3.3.21.1, Section 8.3.3.22.1 Initiator to Responder Discover Identity (NAK) 1. Discover Identity REQ Command 2. Discover Identity NAK Command Section 8.3.2.14.1.2 Initiator to Responder Discover Identity (BUSY) 1. Discover Identity REQ Command 2. Discover Identity BUSY Command Section 8.3.2.14.1.3 Initiator to Responder Discover SVIDs (ACK) 1. Discover SVIDs REQ Command 2. Discover SVIDs ACK Command Section 8.3.2.14.2.1 Section 8.3.3.21.2, Section 8.3.3.22.2 Initiator to Responder Discover SVIDs (NAK) 1. Discover SVIDs REQ Command 2. Discover SVIDs NAK Command Section 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (BUSY) 1. Discover SVIDs REQ Command 2. Discover SVIDs BUSY Command Section 8.3.2.14.2.3 Initiator to Responder Discover Modes (ACK) 1. Discover Modes REQ Command 2. Discover Modes ACK Command Section 8.3.2.14.3.1 Section 8.3.3.21.3, Section 8.3.3.22.3 Initiator to Responder Discover Modes (NAK) 1. Discover Modes REQ Command 2. Discover Modes NAK Command Section 8.3.2.14.3.2 Initiator to Responder Discover Modes (BUSY) 1. Discover Modes REQ Command 2. Discover Modes BUSY Command Section 8.3.2.14.3.3 DFP to UFP Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Started by DFP Section 8.3.2.14.4.1 Section 8.3.3.23.1, Section 8.3.3.24.1 DFP to UFP Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.2 Section 8.3.3.23.2, Section 8.3.3.24.2 DFP to Cable Plug Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Section 8.3.2.14.4.3 Section 8.3.3.23.1, Section 8.3.3.25.4.1 DFP to Cable Plug Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.4 Section 8.3.3.23.2, Section 8.3.3.25.4.2 Initiator to Responder Attention 1. Attention REQ Command Started by Initiator Section 8.3.2.14.4.5 Section 8.3.3.21.4, Section 8.3.3.22.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 445 8.3.2.1.3.24 AMS: Built-In Self-Test (BIST) 8.3.2.1.3.25 AMS: Enter USB 8.3.2.1.3.26 AMS: Unstructured VDM Table 8.28 AMS: Built-In Self-Test (BIST) AMS Message Sequence Conditions AMS Ref State Machine Ref BIST Carrier Mode 1. BIST (BIST Carrier Mode) Message Started by Tester Section 8.3.2.15.1 Section 8.3.3.27.1 BIST Test Data Mode 1. BIST (BIST Test Data) Message Section 8.3.2.15.2 Section 8.3.3.27.2 BIST Shared Capacity Test Mode 1. BIST (BIST Shared Test Mode Entry) Message 2. Series of Messages 3. BIST (BIST Shared Test Mode Exit) Message Section 8.3.2.15.3 Section 8.3.3.27.3 Table 8.29 AMS: Enter USB AMS Message Sequence Conditions AMS Ref State Machine Ref UFP Entering USB4® Mode (Accept) 1. Enter_USB Message 2. Accept Message Started by DFP Section 8.3.2.16.1.1 Section 8.3.3.16.1, Section 8.3.3.16.2 UFP Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.1.2 UFP Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.1.3 Cable Plug Entering USB4 Mode (Accept) 1. Enter_USB Message 2. Accept Message Section 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.2.3 Table 8.30 AMS: Unstructured VDM AMS Message Sequence AMS Ref State Machine Ref Unstructured VDM 1. Unstructured Vendor_Defined Message Section 8.3.2.17.1 VDEM 1. Vendor_Defined_Extended Message Section 8.3.2.17.2 Page 446 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.27 AMS: Hard Reset Table 8.31 AMS: Hard Reset AMS Interruptibl e Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.1, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3 Sink Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.6.2, Section 8.3.2.2.1.1 Source Initiated Hard Reset – Sink Long Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.3, Section 8.3.2.2.1.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 447 8.3.2.2 Power Negotiation 8.3.2.2.1 SPR 8.3.2.2.1.1 SPR Explicit Contract Negotiation 8.3.2.2.1.1.1 SPR Explicit Contract Negotiation (Accept) Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through 5 distinct phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  For SPR PPS operation:  the Source starts its keep alive timer.  the Sink starts its request timer to send periodic Request Messages. Page 448 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.5 Successful Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer For PPS operation start PPSRequestTimer New Power level Evaluate Capabilities Detect plug type Evaluate Request Prepare for new power Source Sink Cable Capabilities detected Plug type detected For PPS operation start PPSTimeoutTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 449 Table 8.32, "Steps for a successful Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.32 Steps for a successful Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 450 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.32 Steps for a successful Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 451 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. New Power Level Negotiated Table 8.32 Steps for a successful Power Negotiation Step Source Sink Page 452 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Reject) Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Reject Message. Figure 8.6 Rejected Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 453 Table 8.33, "Steps for a rejected Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 454 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 455 8.3.2.2.1.1.3 SPR Explicit Contract Negotiation (Wait) Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Wait Message. Figure 8.7 Wait response to Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Page 456 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.34, "Steps for a Wait response to a Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 457 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink Page 458 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.2 SPR PPS Keep Alive This is an example of SPR PPS keep alive operation during an Explicit Contract with SPR PPS as the APDO. Figure 8.8, "SPR PPS Keep Alive" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.8 SPR PPS Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer Stop PPSCommTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer Stop PPSRequestTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Send Ping if required to maintain activity Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer Start PPSRequestTimer New Power level Evaluate Request Prepare for new power Source Sink PPSRequestTimer Timeout Start PPSCommTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 459 Table 8.35, "Steps for SPR PPS Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.8, "SPR PPS Keep Alive" above. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink 1 The SinkPPSPeriodicTimer times out in the Policy Engine. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourcePPSCommTimer. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Page 460 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 27 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 461 8.3.2.2.1.3 SPR Sink Makes Request 8.3.2.2.1.3.1 SPR Sink Makes Request (Accept) This is an example of SPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.9, "SPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.9 SPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate Request Prepare for new power Source Sink Page 462 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.36, "Steps for SPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.9, "SPR Sink Makes Request (Accept)" above. Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 463 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink Page 464 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.3.2 SPR Sink Makes Request (Reject) This is an example of SPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.10, "SPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.10 SPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 465 Table 8.37, "Steps for SPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.10, "SPR Sink Makes Request (Reject)" above. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 466 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 467 8.3.2.2.1.3.3 SPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.11, "SPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.11 SPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate Request Source Sink Page 468 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.38, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.11, "SPR Sink Makes Request (Wait)" above. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 469 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 470 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2 EPR 8.3.2.2.2.1 Entering EPR Mode 8.3.2.2.2.1.1 Entering EPR Mode (Success) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process succeeds. Figure 8.12, "Entering EPR Mode (Success)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.12 Entering EPR Mode (Success) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode entered Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is EPR Capable 21: Send EPR_Mode (Enter Succeeded) 22: EPR_Mode (Enter Succeeded) 23: EPR_Mode (Enter Succeeded) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Succeeded) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Succeeded) 25: EPR_Mode (Enter Succeeded) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 471 Table 8.39, "Steps for Entering EPR Mode (Success)" below provides a detailed explanation of what happens at each labeled step in Figure 8.12, "Entering EPR Mode (Success)" above. Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter)Source_Capabilities Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 472 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source is now the VCONN Source and has determined that the Sink and the cable are EPR Capable. The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Succeeded) Message. 22 Protocol Layer creates the EPR_Mode (Enter Succeeded) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Succeeded) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Succeeded) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Succeeded) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Succeeded) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Entered Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 473 8.3.2.2.2.1.2 Entering EPR Mode (Failure due to non-EPR cable) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to the cable not being capable of EPR. Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.13 Entering EPR Mode (Failure due to non-EPR cable) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is not EPR Capable 21: Send EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) 23: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Failed) 25: EPR_Mode (Enter Failed) received Page 474 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.40, "Steps for Entering EPR Mode (Failure due to non-EPR cable)" below provides a detailed explanation of what happens at each labeled step in Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" above. Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 475 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR; cable is not EPR Capable. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 22 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source Page 476 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.1.3 Entering EPR Mode (Failure of VCONN Swap) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to a failure of the VCONN Swap process. Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.14 Entering EPR Mode (Failure of VCONN Swap) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source fails to become VCONN Source 20: Send EPR_Mode (Enter Failed) 21: EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 25: GoodCRC 26: GoodCRC + CRC 27: GoodCRC 28: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 23: EPR_Mode (Enter Failed) 24: EPR_Mode (Enter Failed) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 477 Table 8.41, "Steps for Entering EPR Mode (Failure of VCONN Swap)" below provides a detailed explanation of what happens at each labeled step in Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" above. Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 478 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". In this case the VCONN Swap process fails. 20 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 21 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 22 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 23 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 24 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 25 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 26 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 27 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 28 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 479 8.3.2.2.2.2 EPR Explicit Contract Negotiation 8.3.2.2.2.2.1 EPR Explicit Contract Negotiation (Accept) Figure 8.15, "Successful Fixed EPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  the Source starts its keep alive timer  the Sink starts its request timer to send periodic EPR_KeepAlive Messages Page 480 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.15 Successful Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer Start SinkEPRKeepAliveTimer New Power level Evaluate EPR Capabilities Evaluate EPR Request Prepare for new power Source Sink Cable EPR_Source_Capabilities detected Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 481 Table 8.42, "Steps for a successful EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.15, "Successful Fixed EPR Power Negotiation" above. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 482 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 483 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. The Policy Engine starts the SinkEPRKeepAliveTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in EPR operation the Policy Engine starts the SourceEPRKeepAliveTimer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Page 484 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Reject) Figure 8.16, "Rejected Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Reject Message. Figure 8.16 Rejected Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 485 Table 8.43, "Steps for a Rejected EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.16, "Rejected Fixed EPR Power Negotiation" above. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 486 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 487 8.3.2.2.2.2.3 EPR Explicit Contract Negotiation (Wait) Figure 8.17, "Wait response to Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Wait Message. Figure 8.17 Wait response to Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Page 488 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.44, "Steps for a Wait response to an EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.17, "Wait response to Fixed EPR Power Negotiation" above. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 489 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink Page 490 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.3 EPR Keep Alive This is an example of keep alive operation during an Explicit Contract in EPR Mode. Figure 8.18, "EPR Keep Alive"shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.18 EPR Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_KeepAlive 2: EPR_KeepAlive 3: EPR_KeepAlive + CRC 4: EPR_KeepAlive Check MessageID against local copy Store copy of MessageID 5: EPR_KeepAlive received Stop SourceEPRKeepAliveTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_KeepAlive sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send EPR_KeepAlive_Ack 11: EPR_KeepAlive_Ack 12: EPR_KeepAlive_Ack + CRC 13: EPR_KeepAlive_Ack Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: EPR_KeepAlive_Ack received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: EPR_KeepAlive_Ack sent Stop SenderResponseTimer Start SinkEPRKeepAliveTimer EPR Mode Continues Evaluate EPR_KeepAlive Source Sink SinkEPRKeepAliveTimer Timeout Stop SinkEPRKeepAliveTimer Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 491 Table 8.45, "Steps for EPR Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.18, "EPR Keep Alive" above. Table 8.45 Steps for EPR Keep Alive Step Source Sink 1 The SinkEPRKeepAliveTimer times out in the Policy Engine. The Policy Engine stops the SinkEPRKeepAliveTimer timer and tells the Protocol Layer to form an EPR_KeepAlive Message. 2 The Protocol Layer creates the EPR_KeepAlive Message and passes it to PHY Layer. The Protocol Layer. 3 PHY Layer receives the EPR_KeepAlive Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_KeepAlive Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourceEPRKeepAliveTimer. 6 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 9 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the SinkEPRKeepAliveTimer Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM to evaluate the SourceEPRKeepAliveTimer Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an EPR_KeepAlive_Ack Message. 11 The Protocol Layer forms the EPR_KeepAlive_Ack Message that is passed to the PHY Layer. 12 PHY Layer appends CRC and sends the EPR_KeepAlive_Ack Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_KeepAlive_Ack Message and compares the CRC it calculated with the one sent to verify the Message. 13 PHY Layer forwards the EPR_KeepAlive_Ack Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the SinkEPRKeepAliveTimer. Page 492 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 18 The Protocol Layer informs the Policy Engine that an EPR_KeepAlive_Ack Message was successfully sent. The Policy Engine starts the SourceEPRKeepAliveTimer. EPR Mode Continues Table 8.45 Steps for EPR Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 493 8.3.2.2.2.4 Exiting EPR Mode 8.3.2.2.2.4.1 Exiting EPR Mode (Sink Initiated) This is an example of an Exit EPR Mode operation where the Sink requests EPR Mode to be exited. Figure 8.19, "Exiting EPR Mode (Sink Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.19 Exiting EPR Mode (Sink Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Page 494 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.46, "Steps for Exiting EPR Mode (Sink Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.19, "Exiting EPR Mode (Sink Initiated)" above. Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 495 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source Page 496 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.4.2 Exiting EPR Mode (Source Initiated) This is an example of an Exit EPR Mode operation where the Source requests EPR Mode to be exited. Figure 8.20, "Exiting EPR Mode (Source Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.20 Exiting EPR Mode (Source Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 497 Table 8.47, "Steps for Exiting EPR Mode (Source Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.20, "Exiting EPR Mode (Source Initiated)" above. Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. Starts CRCReceiveTimer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Page 498 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 499 8.3.2.2.2.5 EPR Sink Makes Request 8.3.2.2.2.5.1 EPR Sink Makes Request (Accept) This is an example of EPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.21, "EPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.21 EPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate EPR_Request Prepare for new power Source Sink Page 500 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.48, "Steps for EPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.21, "EPR Sink Makes Request (Accept)" above. Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 501 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink Page 502 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.5.2 EPR Sink Makes Request (Reject) This is an example of EPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.22, "EPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.22 EPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 503 Table 8.49, "Steps for EPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.22, "EPR Sink Makes Request (Reject)" above. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 504 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 505 8.3.2.2.2.5.3 EPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.23, "EPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.23 EPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Page 506 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.50, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.23, "EPR Sink Makes Request (Wait)" above. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 507 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 508 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.3 Unsupported Message This is an example of the response to an Unsupported Message. Figure 8.24, "Unsupported message" shows the Messages as they flow across the bus and within the devices. Figure 8.24 Unsupported message : Protocol 1: Send Message : PHY : PHY : Protocol 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer 5: Message received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Message sent Start SenderResponseTimer 10: Send Not_supported 11: Not_supported 12: Not_supported + CRC 13: Not_supported 14: Not_supported received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Not_supported sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Message Initiator Message Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 509 Table 8.51, "Steps for an Unsupported Message" below provides a detailed explanation of what happens at each labeled step in Figure 8.24, "Unsupported message" above. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder 1 The Policy Engine directs the Protocol Layer to generate a Message. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Not_Supported Message. 11 Protocol Layer creates the Not_Supported Message and passes to PHY Layer. 12 PHY Layer receives the Not_Supported Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Not_Supported Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Not_Supported Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 510 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Not_Supported Message was successfully sent. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 511 8.3.2.4 Soft Reset This is an example of a Soft Reset operation. Figure 8.25, "Soft Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Soft Reset. Figure 8.25 Soft Reset : Protocol 1: Send Soft Reset : PHY : PHY : Protocol 2: Soft Reset 3: Soft Reset + CRC 4: Soft Reset Start CRCReceiveTimer 5: Soft Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Soft Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Reset Complete, Explicit Contract negotiation Reset Initiator Reset Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 512 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.52, "Steps for a Soft Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.25, "Soft Reset" above. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder 1 The Policy Engine directs the Protocol Layer to generate a Soft_Reset Message to request a Soft Reset. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Soft_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Soft_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Soft_Reset Message to the Protocol Layer. 5 Protocol Layer does not check the MessageID in the incoming Message and resets MessageIDCounter, stored MessageID and RetryCounter. The Protocol Layer forwards the received Soft_Reset Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Soft_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 513 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The reset is complete and protocol communication can restart. Port Partners perform an Explicit Contract Negotiation to re- synchronize their state machines. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder Page 514 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5 Data Reset 8.3.2.5.1 DFP Initiated Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP is also the VCONN Source and initiates a Data Reset. Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.26 DFP Initiated Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Tell DPM to perform Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete Start CRCReceiveTimer 23: Data_Reset_Complete received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 515 Table 8.53, "Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" above. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to perform a Data Reset. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 516 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The Data Reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 517 8.3.2.5.2 DFP Receives Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and is the VCONN Source. Figure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.27 DFP Receives Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Tell DPM to perform a Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete 23: Data_Reset_Complete received Inform DPM Data Reset is complete 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Page 518 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.54, "Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource" below provides a detailed explanation of what happens at each labeled step in FFigure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" above. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 519 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the DPM to perform a Data Reset. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Page 520 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.3 DFP Initiated Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP initiates a Data Reset and the UFP is the VCONN Source. Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.28 DFP Initiated Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Start VCONNDischargeTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset Request DPM to turn off VCONN DPM indicates VCONN is off 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete Start CRCReceiveTimer 32: Data_Reset_Complete received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 521 Table 8.55, "Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" above. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and starts the VCONNDischargeTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 522 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests the DPM to turn off VCONN. 19 When the DPM indicates VCONN has been turned off the Policy Engine tells the Protocol Layer to form an PS_RDY Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 22 Protocol Layer stores the MessageID of the incoming Message. 23 The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and tells the DPM to perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 523 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Page 524 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.4 DFP Receives Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and the UFP is the VCONN Source. Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.29 DFP Receives a Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer Tell DPM to turn off VCONN. 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Start VCONNDischargeTimer DPM indicates that VCONN has been turned off. 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete 32: Data_Reset_Complete received Inform DPM Data Reset is complete 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 525 Table 8.56, "Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" above. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to turn off VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 526 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNDischargeTimer. 19 When the DPM indicates that VCONN has been turned off the Policy Engine directs the Protocol Layer to generate a PS_RDY Message to request a Soft Reset. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and requests the DPM perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 527 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Page 528 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6 Hard Reset The following sections describe the steps required for a USB Power Delivery Hard Reset. The Hard Reset returns the operation of the USB Power Delivery to default Power Role/Data Role and operating voltage/current. During the Hard Reset USB Power Delivery PHY Layer communications Shall be disabled preventing communication between the Port Partner. Note: Hard Reset, in this case, is applied to the USB Power Delivery capability of an individual Port on which the Hard Reset is requested. A side effect of the Hard Reset is that it might reset other functions on the Port such as USB. 8.3.2.6.1 Source Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Source. Figure 8.30, "Source initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.30 Source initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink Hard Reset Complete Reset MessageIDCounter and RetryCounter Reset MessageIDCounter and RetryCounter 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN 9: Hard Reset Complete Channel enabled Channel enabled 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN Channel disabled Channel disabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 529 Table 8.57, "Steps for Source initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.30, "Source initiated Hard Reset" above. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter and RetryCounter. 5 The Protocol Layer informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation. and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Page 530 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 531 8.3.2.6.2 Sink Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Sink. Figure 8.31, "Sink Initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.31 Sink Initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 9: Hard Reset Complete Channel enabled 2: Send Hard Reset 5: Hard Reset received Channel enabled Page 532 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.58, "Steps for Sink initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.31, "Sink Initiated Hard Reset" above. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 533 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink Page 534 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6.3 Source Initiated Hard Reset - Sink Long Reset This is an example of a Hard Reset operation when initiated by a Source. In this example the Sink is slow responding to the reset causing the Source to send multiple Source_Capabilities Messages before it receives a GoodCRC Message response. Figure 8.32, "Source initiated reset - Sink long reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.32 Source initiated reset - Sink long reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 6: Power Supply Reset 11: Power Sink Reset 13: Send Capabilities 14: Capabilities 15: Capabilities + CRC 16: Capabilities Start CRCReceiveTimer Store copy of MessageID 17: Capabilities received 18: GoodCRC 19: GoodCRC + CRC 20: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 21: Capabilities sent Stop SourceCapabilitiesTimer Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 8: Send Capabilities 9: Capabilities 10: Capabilities + CRC Run SourceCapabilityTimer Send Capabilities messages until GoodCRC response is received. 12: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 7: Hard Reset Complete Channel enabled Channel enabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 535 Table 8.59, "Steps for Source initiated Hard Reset - Sink long reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.32, "Source initiated reset - Sink long reset" above. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 8 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Policy Engine starts the SourceCapabilityTimer. The SourceCapabilityTimer times out one or more times until a GoodCRC Message response is received. 9 Protocol Layer creates the Message and passes to PHY Layer. 10 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. Note: Source_Capabilities Message not received since channel is disabled. 11 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. Page 536 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 12 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 13 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Starts the SourceCapabilityTimer. 14 Protocol Layer creates the Message and passes to PHY Layer. 15 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 16 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 17 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 18 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 19 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 20 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 21 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the SourceCapabilityTimer, stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 537 8.3.2.7 Power Role Swap 8.3.2.7.1 Source Initiated Power Role Swap 8.3.2.7.1.1 Source Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap sequence. Page 538 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.33 Successful Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply stops sourcing power CC -> Rd 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Tell Power Supply to stop sourcing power Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Sink to start sinking power Reset Protocol Layer New Power Roles Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 539 Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" above. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine requests its power supply to stop supplying power and stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 540 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the PSSourceOffTimer and tells the power supply to stop sinking current. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Message to Sink, creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 541 30 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Page 542 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.1.2 Source Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  An Reject Message in response to the PR_Swap Message. Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.34 Rejected Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 543 Table 8.61, "Steps for a Rejected Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" above. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 544 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 545 8.3.2.7.1.3 Source Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, with a wait response, initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.35 Power Role Swap Sequence with wait Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 546 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.62, "Steps for a Source Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" above. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 547 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port Page 548 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2 Sink Initiated Power Role Swap 8.3.2.7.2.1 Sink Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 549 Figure 8.36 Successful Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Supply to start sinking power Reset Protocol Layer Tell Power Supply to stop sourcing power Power Supply stops sourcing power CC -> Rd Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 550 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" above. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer and tells the power supply to stop sinking current. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 551 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the power supply to stop supplying power. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 552 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer, informs the power supply that it can start consuming power. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 553 8.3.2.7.2.2 Sink Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Reject Message in response to the PR_Swap Message. Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.37 Rejected Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 554 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.64, "Steps for a Rejected Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" above. Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 555 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 556 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2.3 Sink Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, responded to with wait, initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.38 Power Role Swap Sequence with wait Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 557 Table 8.65, "Steps for a Sink Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" above. Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 558 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Wait Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 559 8.3.2.8 Fast Role Swap This is an example of a successful Fast Role Swap operation initiated by a Port that is initially a Source and therefore has Rp pulled up on its CC wire and which has lost power and needs to get vSafe5V quickly. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are several distinct phases to the Fast Role Swap Negotiation:  The Initial Source stops driving its power output which starts transitioning to vSafe0V and send the Fast Role Swap Request on the CC wire; these could occur in either order or simultaneously.  The Initial Sink stops sinking power. At this point the New Source still has Rd asserted and the New Sink still has Rp asserted.  An FR_Swap Message is sent by the New Source within tFRSwapInit of detecting the Fast Swap signal.  An Accept Message is sent by the New Sink in response to the FR_Swap Message.  The New Sink asserts Rd and sends a PS_RDY Message indicating that the voltage on VBUS is at or below vSafe5V.  The New Source asserts Rp and sends a PS_RDY Message indicating that it is acting as a Source and is sup- plying vSafe5V. Note: The New Source can start applying VBUS when VBUS is at or below vSafe5V (max) but will start driving VBUS to vSafe5V no later than tSrcFRSwap after detecting both the Fast Role Swap Request and that VBUS has dropped below vSafe5V (min). Figure 8.39, "Successful Fast Role Swap Sequence" shows the Messages as they flow across the bus and within the devices to accomplish the Fast Role Swap. Page 560 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.39 Successful Fast Role Swap Sequence : Protocol 1: Send FR_Swap : PHY : PHY : Protocol 2:FR_Swap 3: FR_Swap + CRC 4: FR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: FR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:FR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate FR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Stop PSSourceOnTimer Reset Protocol Layer Power Supply acting as a Sink and VBUS at or below vSafe5V CC -> Rd vSafe5V is being sourced by the new Source Stop PSSourceOffTimer CC -> Rp New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Tell Power Supply to Stop sourcing power and switch to Sink operation Signal Fast Swap on the CC Wire Fast Role Swap signal detected on CC Wire Tell Power Supply to stop sinking current. Fast Swap signal (CC driven to Gnd through rFRSwapTx or rFRSwapCableTx) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 561 Table 8.66, "Steps for a Successful Fast Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.39, "Successful Fast Role Swap Sequence" above. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. The DPM detects Fast Swap on the CC wire and tells the power supply to stop sinking current. The Policy Engine directs the Protocol Layer to send an FR_Swap Message within tFRSwapInit of detecting the Fast Swap signal. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. The DPM tells the Power Supply to stop sourcing power and switch to Sink operation. The DPM signals Fast Swap on the CC wire by driving CC to ground with a resistance of less than rFRSwapTx for at least tFRSwapTx. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the FR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the FR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received FR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the FR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer. Page 562 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The Policy Engine determines its power supply is no longer supplying VBUS and is acting as a Sink. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 563 28 The Policy Engine directs the DPM to apply the Rp pull up. Note: At some point (either before or after receiving the PS_RDY Message) the New Source has ap- plied vSafe5V no later than tSrcFRSwap after detecting the Fast Role Swap Request and that VBUS has dropped below vSafe5V. Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Fast Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Page 564 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9 Data Role Swap 8.3.2.9.1 Data Role Swap, Initiated by UFP Operating as Sink 8.3.2.9.1.1 Data Role Swap, Initiated by UFP Operating as Sink (Accept) Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.40 Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 565 Table 8.67, "Steps for Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" above. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 566 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 567 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.41 Rejected Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Page 568 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.68, "Steps for Rejected Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" above. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 569 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Page 570 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Sink (Wait) Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.42 Data Role Swap with Wait, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 571 Table 8.69, "Steps for Data Role Swap with Wait, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" above. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 572 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 573 8.3.2.9.2 Data Role Swap, Initiated by UFP Operating as Source 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Accept) Figure 8.43, "Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.43 Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 574 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.70, "Steps for Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.43, "Data Role Swap, UFP operating as Source initiates" above. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 575 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), and Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and still operating as a Sink (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 576 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Reject) Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.44 Rejected Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 577 Table 8.71, "Steps for Rejected Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" above. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 578 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 579 8.3.2.9.2.3 Data Role Swap, Initiated by UFP Operating as Source (Wait) Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.45 Data Role Swap with Wait, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Page 580 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.72, "Steps for Data Role Swap with Wait, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" above. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 581 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 582 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3 Data Role Swap, Initiated by DFP Operating as Source 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Accept) Figure 8.46, "Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.46 Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 583 Table 8.73, "Steps for Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.46, "Data Role Swap, DFP operating as Source initiates" above. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 584 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 585 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Reject) Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.47 Rejected Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 586 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.74, "Steps for Rejected Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" above. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 587 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Page 588 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Source (Wait) Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed by wait. Figure 8.48 Data Role Swap with Wait, DFP operating as Source initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 589 Table 8.75, "Steps for Data Role Swap with Wait, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" above. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 590 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 591 8.3.2.9.4 Data Role Swap, Initiated by DFP Operating as Sink 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Accept) Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.49 Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) Page 592 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.76, "Steps for Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" above. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 593 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP, still operating as a Sink (Rd asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 594 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Reject) Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.50 Rejected Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 595 Table 8.77, "Steps for Rejected Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" above. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 596 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 597 8.3.2.9.4.3 Data Role Swap, Initiated by DFP Operating as Sink (Wait) Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.51 Data Role Swap with Wait, DFP operating as Sink initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Page 598 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.78, "Steps for Data Role Swap with Wait, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" above. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 599 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 600 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10 VCONN Swap 8.3.2.10.1 VCONN Source Swap, initiated by VCONN Source 8.3.2.10.1.1 VCONN Source Swap, initiated by VCONN Source (Accept) Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source role. Figure 8.52 Successful VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Vconn is on 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Stop SenderResponseTimer Start VCONNOnTimer Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN has been swapped VCONN off VCONN Source Tell power supply to start supplying VCONN VCONN is off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 601 Table 8.79, "Steps for Source to Sink VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" above. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 602 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine asks the DPM to turn on VCONN. 19 The DPM informs the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Source it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 VCONN is off. Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Port Partners have swapped VCONN Source role. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 603 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Reject) Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.53 Rejected VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Page 604 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.80, "Steps for Rejected VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" above. Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 605 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off Page 606 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.1.3 VCONN Source Swap, initiated by VCONN Source (Wait) Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is told to wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.54 VCONN Source Swap with Wait, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 607 Table 8.81, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" above. Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 608 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 609 8.3.2.10.2 VCONN Source Swap, initiated by non-VCONN Source 8.3.2.10.2.1 VCONN Source Swap, initiated by non-VCONN Source (Accept) Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source. Figure 8.55 VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port Vconn is on Start VCONNOnTimer VCONN Source VCONN Off Stop SenderResponseTimer Tell power supply to start supplying VCONN 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Source is supplying VCONN Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN is off Page 610 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.82, "Steps for VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" above. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 611 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNOnTimer. 19 The DPM tells the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Sink it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. VCONN is off. The Port Partners have swapped VCONN Source role. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Page 612 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.2.2 VCONN Source Swap, initiated by non-VCONN Source (Reject) Figure 8.56, "Rejected VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap which is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.56 Rejected VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 613 Table 8.83, "Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.56, "Rejected VCONN Source Swap, initiated by non- VCONN Source" above. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 614 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 615 8.3.2.10.2.3 VCONN Source Swap (Wait) Figure 8.57, "VCONN Source Swap with Wait" shows an example where the Port requests a VCONN Swap which is delayed with a wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.57 VCONN Source Swap with Wait : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Page 616 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.84, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.57, "VCONN Source Swap with Wait" above. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 617 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source Page 618 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11 Additional Capabilities, Status and Information 8.3.2.11.1 Alert 8.3.2.11.1.1 Source sends Alert to a Sink Figure 8.58, "Source Alert to Sink" shows an example sequence between a Source and a Sink where the Source alerts the Sink that there has been a status change. This AMS will be followed by getting the Source status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.58 Source Alert to Sink : Sink Policy Engine : Protocol : PHY : PHY : Protocol : Source Policy Engine Sink Port Source Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 619 Table 8.85, "Steps for Source Alert to Sink" below provides a detailed explanation of what happens at each labeled step in Figure 8.58, "Source Alert to Sink" above. Table 8.85 Steps for Source Alert to Sink Step Sink Source 1 The DPM indicates a Source alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 620 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.1.2 Sink sends Alert to a Source Figure 8.59, "Sink Alert to Source" shows an example sequence between a Source and a Sink where the Sink alerts the Source that there has been a status change. This AMS will be followed by getting the Sink status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.59 Sink Alert to Source : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine Source Port Sink Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 621 Table 8.86, "Steps for Sink Alert to Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.59, "Sink Alert to Source" above. Table 8.86 Steps for Sink Alert to Source Step Source Sink 1 The DPM indicates a Sink alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 622 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2 Status 8.3.2.11.2.1 Sink Gets Source Status Figure 8.60, "Sink Gets Source Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Sink gets more details on the change. Figure 8.60 Sink Gets Source Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 623 Table 8.87, "Steps for a Sink getting Source Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.60, "Sink Gets Source Status" above. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 624 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Source has informed the Sink of its present status. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 625 8.3.2.11.2.2 Source Gets Sink Status Figure 8.61, "Source Gets Sink Status" shows an example sequence between a Source and a Sink where, after the Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Source gets more details on the change. Figure 8.61 Source Gets Sink Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink Status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Page 626 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.88, "Steps for a Source getting Sink Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.61, "Source Gets Sink Status" above. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 627 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Sink has informed the Source of its present status. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port Page 628 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2.3 VCONN Source Gets Cable Plug Status Figure 8.62, "VCONN Source Gets Cable Plug Status" shows an example sequence between a VCONN Source and a Cable Plug where, after the VCONN Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the VCONN Source gets more details on the change. Figure 8.62 VCONN Source Gets Cable Plug Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Status Information from DPM : Policy Engine : Policy Engine VCONN Source Port Cable Plug Stop SenderResponseTimer 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 629 Table 8.89, "Steps for a VCONN Source getting Cable Plug Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.62, "VCONN Source Gets Cable Plug Status" above. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug 1 Policy Engine directs the Protocol Layer to send a Get_Status Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 630 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Cable Plug has informed the VCONN Source of its present status. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 631 8.3.2.11.2.4 Sink Gets Source PPS Status Figure 8.63, "Sink Gets Source PPS Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a PPS status change, the Sink gets more details on the change. Figure 8.63 Sink Gets Source PPS Status : Protocol 1: Send Get_PPS_Status : PHY : PHY : Protocol 2:Get_PPS_Status 3: Get_PPS_Status + CRC 4: Get_PPS_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_PPS_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_PPS_Status sent Start SenderResponseTimer 10: Send PPS_Status 11: PPS_Status 12: PPS_Status + CRC 13: PPS_Status Check MessageID against local copy Store copy of MessageID 14: PPS_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source PPS Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: PPS_Status sent Page 632 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.90, "Steps for a Sink getting Source PPS status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.63, "Sink Gets Source PPS Status" above. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_PPS_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_PPS_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_PPS_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_PPS_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_PPS_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a PPS_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the PPS_Status Message. PHY Layer appends a CRC and sends the PPS_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PPS_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 633 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PPS_Status Message was successfully sent. The Source has informed the Sink of its present PPS status. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port Page 634 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3 Source/Sink Capabilities 8.3.2.11.3.1 SPR 8.3.2.11.3.1.1 Sink Gets Source Capabilities Figure 8.64, "Sink Gets Source's Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source Capabilities. Figure 8.64 Sink Gets Source's Capabilities : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Source_Capabilities sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 635 Table 8.91, "Steps for a Sink getting Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.64, "Sink Gets Source's Capabilities" above. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 636 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its capabilities. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 637 8.3.2.11.3.1.2 Dual-Role Source Gets Source Capabilities from a Dual-Role Sink Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as a Source. Figure 8.65 Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 638 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.92, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" above. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 639 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its capabilities. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 640 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.1.3 Source Gets Sink Capabilities Figure 8.66, "Source Gets Sink's Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink Capabilities. Figure 8.66 Source Gets Sink's Capabilities : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 641 Table 8.93, "Steps for a Source getting Sink Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.66, "Source Gets Sink's Capabilities" above. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 642 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its capabilities. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 643 8.3.2.11.3.1.4 Dual-Role Sink Get Sink Capabilities from a Dual-Role Source Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.67 Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 644 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.94, "Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" above. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 645 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as a Sink. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 646 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2 EPR 8.3.2.11.3.2.1 Sink Gets EPR Source Capabilities Figure 8.68, "Sink Gets Source's EPR Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's EPR Capabilities. Figure 8.68 Sink Gets Source's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 647 Table 8.95, "Steps for a Sink getting EPR Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.68, "Sink Gets Source's EPR Capabilities" above. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present EPR Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 648 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its EPR Capabilities. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 649 8.3.2.11.3.2.2 Dual-Role Source Gets Source Capabilities from a Dual-Role EPR Sink Figure 8.69, "Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as an EPR Source. Figure 8.69 Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 650 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.96, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.69, "Dual-Role Source Gets Dual- Role Sink's Capabilities as an EPR Source" above. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 651 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its EPR Capabilities. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 652 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2.3 Source Gets Sink EPR Capabilities Figure 8.70, "Source Gets Sink's EPR Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's EPR Capabilities. Figure 8.70 Source Gets Sink's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 653 Table 8.97, "Steps for a Source getting Sink EPR Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.70, "Source Gets Sink's EPR Capabilities" above. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 654 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its EPR Capabilities. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 655 8.3.2.11.3.2.4 Dual-Role Sink Get Sink EPR Capabilities from a Dual-Role Source Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.71 Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 656 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.98, "Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" above. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 657 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as an EPR Sink. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 658 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4 Extended Capabilities 8.3.2.11.4.1 Sink Gets Source Extended Capabilities Figure 8.72, "Sink Gets Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Extended Capabilities. Figure 8.72 Sink Gets Source's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 659 Table 8.99, "Steps for a Sink getting Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.72, "Sink Gets Source's Extended Capabilities" above. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 660 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Source has informed the Sink of its Extended Capabilities. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 661 8.3.2.11.4.2 Dual-Role Source Gets Source Capabilities Extended from a Dual- Role Sink Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Source gets the Dual-Role Power Sink's Extended Capabilities as a Source. Figure 8.73 Dual-Role Source Gets Dual-Role Sink's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 662 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.100, "Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" above. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Source which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 663 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its Extended Capabilities as a Source. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 664 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4.3 Source Gets Sink Extended Capabilities Figure 8.74, "Source Gets Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Extended Capabilities. Figure 8.74 Source Gets Sink's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 665 Table 8.101, "Steps for a Source getting Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.74, "Source Gets Sink's Extended Capabilities" above. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 666 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Sink has informed the Source of its Extended Capabilities. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 667 8.3.2.11.4.4 Dual-Role Sink Gets Sink Capabilities Extended from a Dual-Role Source Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Sink gets the Dual-Role Power Source's Extended Capabilities as a Sink. Figure 8.75 Dual-Role Sink Gets Dual-Role Source's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 668 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.102, "Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" above. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Sink which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 669 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Extended Capabilities as a Sink. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 670 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5 Battery Capabilities and Status 8.3.2.11.5.1 Sink Gets Battery Capabilities Figure 8.76, "Sink Gets Source's Battery Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery capabilities for a given Battery. Figure 8.76 Sink Gets Source's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 671 Table 8.103, "Steps for a Sink getting Source Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.76, "Sink Gets Source's Battery Capabilities" above. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 672 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Source has informed the Sink of the Battery capabilities for the requested Battery. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 673 8.3.2.11.5.2 Source Gets Battery Capabilities Figure 8.77, "Source Gets Sink's Battery Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery capabilities for a given Battery. Figure 8.77 Source Gets Sink's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 674 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.104, "Steps for a Source getting Sink Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.77, "Source Gets Sink's Battery Capabilities" above. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 675 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Sink has informed the Source of the Battery capabilities for the requested Battery. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port Page 676 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5.3 Sink Gets Battery Status Figure 8.78, "Sink Gets Source's Battery Status" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery status for a given Battery. Figure 8.78 Sink Gets Source's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 677 Table 8.105, "Steps for a Sink getting Source Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.78, "Sink Gets Source's Battery Status" above. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 678 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Source has informed the Sink of the Battery status for the requested Battery. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 679 8.3.2.11.5.4 Source Gets Battery Status Figure 8.79, "Source Gets Sink's Battery Status" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery status for a given Battery. Figure 8.79 Source Gets Sink's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 680 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.106, "Steps for a Source getting Sink Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.79, "Source Gets Sink's Battery Status" above. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 681 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Sink has informed the Source of the Battery status for the requested Battery. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port Page 682 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6 Manufacturer Information 8.3.2.11.6.1 Source Gets Port Manufacturer Information from a Sink Figure 8.80, "Source Gets Sink's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.80 Source Gets Sink's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 683 Table 8.107, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.80, "Source Gets Sink's Port Manufacturer Information" above. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 684 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 685 8.3.2.11.6.2 Sink Gets Port Manufacturer Information from a Source Figure 8.81, "Sink Gets Source's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.81 Sink Gets Source's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 686 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.108, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.81, "Sink Gets Source's Port Manufacturer Information" above. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 687 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port Page 688 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.3 Source Gets Battery Manufacturer Information from a Sink Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for one of its Batteries. Figure 8.82 Source Gets Sink's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 689 Table 8.109, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" above. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 690 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 691 8.3.2.11.6.4 Sink Gets Battery Manufacturer Information from a Source Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.83 Sink Gets Source's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 692 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.110, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" above. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 693 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port Page 694 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.5 VCONN Source Gets Manufacturer Information from a Cable Plug Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Manufacturer information. Figure 8.84 VCONN Source Gets Cable Plug's Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 695 Table 8.111, "Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" above. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 696 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Cable Plug has informed the Source of its manufacturer information. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 697 8.3.2.11.7 Country Codes 8.3.2.11.7.1 8.3.2.12.7.1Source Gets Country Codes from a Sink Figure 8.85, "Source Gets Sink's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's Country Codes. Figure 8.85 Source Gets Sink's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 698 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.112, "Steps for a Source getting Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.85, "Source Gets Sink's Country Codes" above. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 699 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port Page 700 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.7.2 Sink Gets Country Codes from a Source Figure 8.86, "Sink Gets Source's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.86 Sink Gets Source's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 701 Table 8.113, "Steps for a Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.86, "Sink Gets Source's Country Codes" above. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 702 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 703 8.3.2.11.7.3 VCONN Source Gets Country Codes from a Cable Plug Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Country Codes. Figure 8.87 VCONN Source Gets Cable Plug's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Codes sent Page 704 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.114, "Steps for a VCONN Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" above. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 705 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Cable Plug has informed the Source of its country codes. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug Page 706 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8 Country Information 8.3.2.11.8.1 Source Gets Country Information from a Sink Figure 8.88, "Source Gets Sink's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country information. Figure 8.88 Source Gets Sink's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 707 Table 8.115, "Steps for a Source getting Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.88, "Source Gets Sink's Country Information" above. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific Country Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 708 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 709 8.3.2.11.8.2 Sink Gets Country Information from a Source Figure 8.89, "Sink Gets Source's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.89 Sink Gets Source's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 710 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.116, "Steps for a Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.89, "Sink Gets Source's Country Information" above. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 711 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port Page 712 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8.3 VCONN Source Gets Country Information from a Cable Plug Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's country information. Figure 8.90 VCONN Source Gets Cable Plug's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 713 Table 8.117, "Steps for a VCONN Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" above. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 714 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Cable Plug has informed the Source of its country information. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 715 8.3.2.11.9 Revision Information 8.3.2.11.9.1 Source Gets Revision Information from a Sink Figure 8.91, "Source Gets Sink's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision information. Figure 8.91 Source Gets Sink's Revision Information : Protocol 1: Send Get_Revision : PHY : PHY : Protocol 2:Get_Revision 3: Get_Revision + CRC 4: Get_Revision Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Revision received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Revision sent Start SenderResponseTimer 10: Send Revision 11: Revision 12: Revision + CRC 13: Revision Check MessageID against local copy Store copy of MessageID 14: Revision received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Revision sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 716 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.118, "Steps for a Source getting Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.91, "Source Gets Sink's Revision Information" above. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 717 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port Page 718 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.9.2 Sink Gets Revision Information from a Source Figure 8.92, "Sink Gets Source's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision codes. Figure 8.92 Sink Gets Source's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 719 Table 8.119, "Steps for a Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.92, "Sink Gets Source's Revision Information" above. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 720 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 721 8.3.2.11.9.3 VCONN Source Gets Revision Information from a Cable Plug Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Revision information. Figure 8.93 VCONN Source Gets Cable Plug's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Page 722 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.120, "Steps for a VCONN Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" above. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 723 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Cable Plug has informed the Source of its Revision information. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug Page 724 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.10 Source Information 8.3.2.11.10.1 Sink Gets Source Information Figure 8.94, "Sink Gets Source's Information" shows an example sequence between a Source and a Sink when the Sink gets the Source's information. Figure 8.94 Sink Gets Source's Information : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 725 Table 8.121, "Steps for a Sink getting Source Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.94, "Sink Gets Source's Information" above. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 726 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Source has provided the Sink with its information. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 727 8.3.2.11.10.2 Dual-Role Source Gets Source Information from a Dual-Role Sink Figure 8.95, "Dual-Role Source Gets Dual-Role Sink's Information as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink's Information as a Source. Figure 8.95 Dual-Role Source Gets Dual-Role Sink's Information as a Source : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 728 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.122, "Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.95, "Dual-Role Source Gets Dual- Role Sink's Information as a Source" above. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 729 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Dual-Role Power Sink has provided the Dual-Role Power Source with its information. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 730 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12 Security 8.3.2.12.1 Source requests security exchange with Sink Figure 8.96, "Source requests security exchange with Sink" shows an example sequence for a security exchange between a Source and a Sink. Figure 8.96 Source requests security exchange with Sink : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 731 Table 8.123, "Steps for a Source requesting a security exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.96, "Source requests security exchange with Sink" above. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 732 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 733 8.3.2.12.2 Sink requests security exchange with Source Figure 8.97, "Sink requests security exchange with Source" shows an example sequence for a security exchange between a Sink and a Source. Figure 8.97 Sink requests security exchange with Source : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 734 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.124, "Steps for a Sink requesting a security exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.97, "Sink requests security exchange with Source" above. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 735 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port Page 736 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12.3 VCONN Source requests security exchange with Cable Plug Figure 8.98, "VCONN Source requests security exchange with Cable Plug" shows an example sequence for a security exchange between a VCONN Source and a Cable Plug. Figure 8.98 VCONN Source requests security exchange with Cable Plug : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Vconn Source Cable Plug 18: Security_Response sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 737 Table 8.125, "Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.98, "VCONN Source requests security exchange with Cable Plug" above. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 738 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 739 8.3.2.13 Firmware Update 8.3.2.13.1 Source requests firmware update exchange with Sink Figure 8.99, "Source requests firmware update exchange with Sink" shows an example sequence for a firmware update exchange between a Source and a Sink. Figure 8.99 Source requests firmware update exchange with Sink : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 740 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.126, "Steps for a Source requesting a firmware update exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.99, "Source requests firmware update exchange with Sink" above. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 741 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port Page 742 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.13.2 Sink requests firmware update exchange with Source Figure 8.100, "Sink requests firmware update exchange with Source" shows an example sequence for a firmware update exchange between a Sink and a Source. Figure 8.100 Sink requests firmware update exchange with Source : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 743 Table 8.127, "Steps for a Sink requesting a firmware update exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.100, "Sink requests firmware update exchange with Source" above. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Page 744 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 745 8.3.2.13.3 VCONN Source requests firmware update exchange with Cable Plug Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" shows an example sequence for a firmware update exchange between a VCONN Source and a Cable Plug. Figure 8.101 VCONN Source requests firmware update exchange with Cable Plug : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine VCONN Source Cable Plug 18: Firmware_Update_Response sent Page 746 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.128, "Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" above. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 747 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Page 748 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14 Structured VDM 8.3.2.14.1 Discover Identity 8.3.2.14.1.1 Initiator to Responder Discover Identity (ACK) Figure 8.102, "Initiator to Responder Discover Identity (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers identity information from the Responder. Figure 8.102 Initiator to Responder Discover Identity (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity ACK 11: Discover Identity ACK 12: Discover Identity ACK + CRC 13: Discover Identity ACK Check MessageID against local copy Store copy of MessageID 14: Discover Identity ACK received Stop VDMResponseTimer DPM evaluates Identity information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 749 Table 8.129, "Steps for Initiator to UFP Discover Identity (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.102, "Initiator to Responder Discover Identity (ACK)" above. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command ACK response. 11 Protocol Layer creates the Discover Identity Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 750 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command ACK response was successfully sent. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 751 8.3.2.14.1.2 Initiator to Responder Discover Identity (NAK) Figure 8.103, "Initiator to Responder Discover Identity (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a NAK. Figure 8.103 Initiator to Responder Discover Identity (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity NAK 11: Discover Identity NAK 12: Discover Identity NAK + CRC 13: Discover Identity NAK Check MessageID against local copy Store copy of MessageID 14: Discover Identity NAK received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Page 752 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.130, "Steps for Initiator to UFP Discover Identity (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.103, "Initiator to Responder Discover Identity (NAK)" above. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command NAK response. 11 Protocol Layer creates the Discover Identity Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 753 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder Page 754 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.1.3 Initiator to Responder Discover Identity (BUSY) Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a BUSY. Figure 8.104 Initiator to Responder Discover Identity (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity BUSY 11: Discover Identity BUSY 12: Discover Identity BUSY + CRC 13: Discover Identity BUSY Check MessageID against local copy Store copy of MessageID 14: Discover Identity BUSY received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 755 Table 8.131, "Steps for Initiator to UFP Discover Identity (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" above. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command BUSY response. 11 Protocol Layer creates the Discover Identity Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 756 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 757 8.3.2.14.2 Discover SVIDs 8.3.2.14.2.1 Initiator to Responder Discover SVIDs (ACK) Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers SVID information from the Responder. Figure 8.105 Initiator to Responder Discover SVIDs (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs ACK 11: Discover_SVIDs ACK 12: Discover_SVIDs ACK + CRC 13: Discover_SVIDs ACK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs ACK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 758 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.132, "Steps for DFP to UFP Discover SVIDs (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" above. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command ACK response. 11 Protocol Layer creates the Discover SVIDs Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 759 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command ACK response was successfully sent. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder Page 760 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (NAK) Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a NAK. Figure 8.106 Initiator to Responder Discover SVIDs (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs NAK 11: Discover_SVIDs NAK 12: Discover_SVIDs NAK + CRC 13: Discover_SVIDs NAK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs NAK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 761 Table 8.133, "Steps for DFP to UFP Discover SVIDs (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" above. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command NAK response. 11 Protocol Layer creates the Discover SVIDs Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 762 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command NAK response was successfully sent. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 763 8.3.2.14.2.3 Initiator to Responder Discover SVIDs (BUSY) Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a BUSY. Figure 8.107 Initiator to Responder Discover SVIDs (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs BUSY 11: Discover_SVIDs BUSY 12: Discover_SVIDs BUSY + CRC 13: Discover_SVIDs BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs BUSY received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 764 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.134, "Steps for DFP to UFP Discover SVIDs (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" above. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command BUSY response. 11 Protocol Layer creates the Discover SVIDs Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 765 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command BUSY response was successfully sent. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder Page 766 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3 Discover Modes 8.3.2.14.3.1 Initiator to Responder Discover Modes (ACK) Figure 8.108, "Initiator to Responder Discover Modes (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers Mode information from the Responder. Figure 8.108 Initiator to Responder Discover Modes (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes ACK 11: Discover_Modes ACK 12: Discover_Modes ACK + CRC 13: Discover_Modes ACK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes ACK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 767 Table 8.135, "Steps for DFP to UFP Discover Modes (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.108, "Initiator to Responder Discover Modes (ACK)". Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command ACK response. 11 Protocol Layer creates the Discover Modes Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 768 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command ACK response was successfully sent. Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 769 8.3.2.14.3.2 Initiator to Responder Discover Modes (NAK) Figure 8.109, "Initiator to Responder Discover Modes (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a NAK. Figure 8.109 Initiator to Responder Discover Modes (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes NAK 11: Discover_Modes NAK 12: Discover_Modes NAK + CRC 13: Discover_Modes NAK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes NAK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Page 770 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.136, "Steps for DFP to UFP Discover Modes (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.109, "Initiator to Responder Discover Modes (NAK)". Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 771 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP Page 772 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3.3 Initiator to Responder Discover Modes (BUSY) Figure 8.110, "Initiator to Responder Discover Modes (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a BUSY. Figure 8.110 Initiator to Responder Discover Modes (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes BUSY 11: Discover_Modes BUSY 12: Discover_Modes BUSY + CRC 13: Discover_Modes BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_Modes BUSY received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 773 Table 8.137, "Steps for DFP to UFP Discover Modes (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.110, "Initiator to Responder Discover Modes (BUSY)". Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 774 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 775 8.3.2.14.4 Enter/Exit Mode 8.3.2.14.4.1 DFP to UFP Enter Mode Figure 8.111, "DFP to UFP Enter Mode" shows an example sequence between a DFP and a UFP that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.111 DFP to UFP Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP Supported SVIDS/Modes discovered Enter USB Safe State 37: Send Enter Mode 38: Enter Mode 39: Enter Mode + CRC 40: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 41: Enter Mode received 42: GoodCRC 43: GoodCRC + CRC 44: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 45: Enter Mode sent Start VDMModeEntryTimer 46: Send Enter Mode ACK 47: Enter Mode ACK 48: Enter Mode ACK + CRC 49: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 50: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 51: GoodCRC 52: GoodCRC + CRC 53: GoodCRC 54: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Operation USB Operation Evaluate Enter Mode request Enter New Mode New Mode Entered Page 776 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.138, "Steps for DFP to UFP Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.111, "DFP to UFP Enter Mode" above. Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. The Policy Engine directs the Protocol Layer to send an Enter Mode Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. The Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 777 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and UFP are operating in the new Mode Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP Page 778 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.2 DFP to UFP Exit Mode Figure 8.112, "DFP to UFP Exit Mode" shows an example sequence between a DFP and a UFP, where the DFP commands the UFP to exit the only Active Mode. Figure 8.112 DFP to UFP Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 779 Table 8.139, "Steps for DFP to UFP Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.112, "DFP to UFP Exit Mode" above. Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The UFP is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. The Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 780 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and UFP are in USB Operation Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 781 8.3.2.14.4.3 DFP to Cable Plug Enter Mode Figure 8.113, "DFP to Cable Plug Enter Mode" shows an example sequence between a DFP and a Cable Plug that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.113 DFP to Cable Plug Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug Supported SVIDs/Modes Discovered Enter USB Safe Mode Wait tCableMessage before transmission 19: Send Enter Mode 20: Enter Mode 21: Enter Mode + CRC 22: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Enter Mode received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Enter Mode sent Start VDMModeEntryTimer 10: Send Enter Mode ACK 11: Enter Mode ACK 12: Enter Mode ACK + CRC 13: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 14: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Mode USB Mode Evaluate Enter Mode request Enter New Mode Wait tCableMessage before transmission New Mode Entered Page 782 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.140, "Steps for DFP to Cable Plug Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.113, "DFP to Cable Plug Enter Mode" above. Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. tCableMessage after the last GoodCRC Message was sent the Policy Engine directs the Protocol Layer to send an Enter Mode Command request. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 783 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and Cable Plug are operating in the new Mode Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug Page 784 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.4 DFP to Cable Plug Exit Mode Figure 8.114, "DFP to Cable Plug Exit Mode" shows an example sequence between a USB Type-C® DFP and a Cable Plug, where the DFP commands the Cable Plug to exit an Active Mode. Figure 8.114 DFP to Cable Plug Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation Wait tCableMessage before transmission USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 785 Table 8.141, "Steps for DFP to Cable Plug Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.114, "DFP to Cable Plug Exit Mode" above. Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The Cable Plug is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 786 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and Cable Plug are in USB Operation Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 787 8.3.2.14.4.5 Initiator to Responder Attention Figure 8.115, "Initiator to Responder Attention" shows an example sequence between an Initiator and a Responder, where the Initiator requests attention from the Responder. Figure 8.115 Initiator to Responder Attention : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Responder Initiator 1: Send Attention 2: Attention 3: Attention + CRC 4: Attention Check MessageID against local copy Store copy of MessageID 5: Attention received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Attention sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Page 788 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.142, "Steps for Initiator to Responder Attention" below provides a detailed explanation of what happens at each labeled step in Figure 8.115, "Initiator to Responder Attention" above. Table 8.142 Steps for Initiator to Responder Attention Step Responder Initiator 1 The DPM requests attention. The Policy Engine tells the Protocol Layer to form an Attention Command request. 2 Protocol Layer creates the Attention Command request and passes to PHY Layer. 3 PHY Layer receives the Attention Command request and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Attention Command request. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Attention Command request information to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Attention Command request was successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 789 8.3.2.15 Built in Self-Test (BIST) 8.3.2.15.1 BIST Carrier Mode The following is an example of a BIST Carrier Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.116, "BIST Carrier Mode Test" shows the Messages as they flow across the bus and within the devices. This test enables the measurement of power supply noise and frequency drift. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Carrier Mode BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT starts sending the Test Pattern. 5) Operator does the measurements. 6) The test ends after tBISTContMode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.1, "BIST Carrier Mode". Figure 8.116 BIST Carrier Mode Test : Protocol 1: Send BIST(Carrier Mode) : PHY : PHY : Protocol 2: BIST(Carrier Mode) 3: BIST(Carrier Mode) + CRC 4: BIST(Carrier Mode) Start CRCReceiveTimer 5: BIST(Carrier Mode) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Carrier Mode) sent : Policy Engine : Policy Engine Go to BIST Carrier Mode Tester UUT 12: Send Test Pattern 13: Send Test Pattern 14: Test Pattern Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (after tBISTContMode) Enter BIST Carrier Mode mode 10: Go to BIST Carrier Mode 11: Go to BIST Carrier Mode Page 790 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.143, "Steps for BIST Carrier Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.116, "BIST Carrier Mode Test" above. Table 8.143 Steps for BIST Carrier Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Carrier Mode, to put the UUT into BIST Carrier Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Carrier Mode. The Policy Engine goes to BIST Carrier Mode. 11 Protocol Layer tells PHY Layer to go into BIST Carrier Mode. UUT enters BIST Carrier Mode. 12 The Policy Engine directs the Protocol Layer to start generation of the Test Pattern. 13 Protocol Layer directs the PHY Layer to generate the Test Pattern. 14 PHY Layer receives the Test Pattern stream. PHY Layer generates a continuous Test Pattern stream. The UUT exits BIST Carrier Mode after tBISTContMode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 791 8.3.2.15.2 BIST Test Data Mode The following is an example of a BIST Test Data Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.117, "BIST Test Data Test" shows the Messages as they flow across the bus and within the devices. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Test Data BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) Steps 2and 3 are repeated any number of times. 5) The test ends after Hard Reset Signaling is issued. See also Section 5.9.2, "BIST Test Data Mode" and Section 6.4.3.2, "BIST Test Data Mode". Page 792 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.117 BIST Test Data Test : Protocol 1: Send BIST(Test Data) : PHY : PHY : Protocol 2: BIST(Test Data) 3: BIST(Test Data) + CRC 4: BIST(Test Data) Start CRCReceiveTimer 5: BIST(Test Data) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Test Data) sent : Policy Engine : Policy Engine Go to BIST Test Data mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (Hard Reset) Enter BIST Test Data mode 10: Send BIST(Test Data) 11: BIST(Test Data) 12: BIST(Test Data) + CRC 13: BIST(Test Data) Start CRCReceiveTimer 14: BIST(Test Data) received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: BIST(Test Data) sent Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 793 Table 8.144, "Steps for BIST Test Data Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.117, "BIST Test Data Test" above. Table 8.144 Steps for BIST Test Data Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. UUT enters BIST Test Data Mode. 10 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 13 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. Page 794 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. Repeat steps 10-18 any number of times The UUT exits BIST Test Data Mode after a Hard Reset Table 8.144 Steps for BIST Test Data Test Step Tester UUT Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 795 8.3.2.15.3 BIST Shared Capacity Test Mode The following is an example of a BIST Shared Capacity Test Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.118, "BIST Share Capacity Mode Test" shows the Messages as they flow across the bus and within the devices. This test places the UUT in a compliance test mode where the maximum Source capability is always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Shared Test Mode Entry BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT enters BIST Shared Capacity Test Mode. 5) Operator does the measurements. 6) Tester sends a BIST Message with a BIST Shared Test Mode Exit BIST Data Object. 7) UUT answers with a GoodCRC Message. 8) UUT exits BIST Shared Capacity Test Mode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.3, "BIST Shared Capacity Test Mode". Figure 8.118 BIST Share Capacity Mode Test 12: Send BIST(Shared Capacity Test Mode Exit) 13: BIST(Shared Capacity Test Mode Exit) 14: BIST(Shared Capacity Test Mode Exit) + CRC 15: BIST(Shared Capacity Test Mode Exit) Start CRCReceiveTimer 16: BIST(Shared Capacity Test Mode Exit) received 17: GoodCRC 18: GoodCRC + CRC 19: GoodCRC 20: BIST(Shared Capacity Test Mode) sent Go to BIST Shared Capacity Test Mode Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID EXit BIST Shared Capacity Test Mode mode 21: Exit BIST Shared Capacity Test Mode 22: Exit BIST Shared Capacity Test Mode : Protocol 1: Send BIST(Shared Capacity Test Mode Entry) : PHY : PHY : Protocol 2: BIST(Shared Capacity Test Mode Entry) 3: BIST(Shared Capacity Test Mode Entry) + CRC 4: BIST(Shared Capacity Test Mode Entry) Start CRCReceiveTimer 5: BIST(Shared Capacity Test Mode Entry) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Shared Capacity Test Mode) sent : Policy Engine : Policy Engine Go to BIST Shared Capacity Test Mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Enter BIST Shared Capacity Test Mode mode 10: Go to BIST Shared Capacity Test Mode 11: Go to BIST Shared Capacity Test Mode Tester Performs Tests Page 796 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.145, "Steps for BIST Shared Capacity Test Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.118, "BIST Share Capacity Mode Test" above. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Entry, to put the UUT into BIST Shared Capacity Test Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY LayerPHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Shared Capacity Test Mode. The Policy Engine goes to BIST Shared Capacity Test Mode. 11 Protocol Layer tells PHY Layer to go into BIST Shared Capacity Test Mode. UUT enters BIST Shared Capacity Test Mode. Tester performs tests. 12 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Exit, to take the UUT out of BIST Shared Capacity Test Mode. 13 Protocol Layer creates the Message and passes to PHY Layer. 14 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 15 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 16 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 797 17 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 18 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 19 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 20 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 21 Policy Engine tells Protocol Layer to exit BIST Shared Capacity Test Mode. The Policy Engine exits to BIST Shared Capacity Test Mode. 22 Protocol Layer tells PHY Layer to exit BIST Shared Capacity Test Mode. UUT exits BIST Shared Capacity Test Mode. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT Page 798 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16 Enter USB 8.3.2.16.1 UFP Entering USB4 Mode 8.3.2.16.1.1 UFP Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the UFP. Figure 8.119, "UFP Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.119 UFP Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 799 Table 8.146, "Steps for UFP USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.119, "UFP Entering USB4 Mode (Accept)" above. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 800 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Both Port Partners enter [USB4] operation. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 801 8.3.2.16.1.2 UFP Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the UFP. Figure 8.120, "UFP Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.120 UFP Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 802 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.147, "Steps for UFP USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.120, "UFP Entering USB4 Mode (Reject)" above. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 803 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP Page 804 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.1.3 UFP Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the UFP at this time. Figure 8.121, "UFP Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.121 UFP Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait 14: Wait received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 805 Table 8.148, "Steps for UFP USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.121, "UFP Entering USB4 Mode (Wait)" above. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 806 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 807 8.3.2.16.2 Cable Plug Entering USB4 Mode 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the Cable Plug. Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.122 Cable Plug Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 808 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.149, "Steps for Cable Plug USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" above. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 809 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Cable Plug enters [USB4] operation. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug Page 810 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the Cable Plug. Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.123 Cable Plug Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 811 Table 8.150, "Steps for Cable Plug USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" above. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 812 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 813 8.3.2.16.2.3 Cable Plug Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the Cable Plug at this time. Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.124 Cable Plug Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 814 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.151, "Steps for Cable Plug USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" above. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 815 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug Page 816 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.17 Unstructured Vendor Defined Messages 8.3.2.17.1 Unstructured VDM Figure 8.125, "Unstructured VDM Message Sequence" shows an example sequence of an Unstructured VDM Transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.125 Unstructured VDM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send Unstructured VDM Start CRCReceive Timer 21 : Unstructured VDM 22 : Unstructured VDM + CRC 23 : Unstructured VDM Check MessageID against local copy Store Copy of MessageID 23 : Unstructured VDM Received Evaluate Unstructured VDM Reply with the application specific response which can be again a Unstructured VDM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send Unstructured VDM 11: Unstructured VDM 18: Unstructured VDM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : Unstructured VDM + CRC 16: GoodCRC + CRC 11: Unstructured VDM 15: GoodCRC 14: Unstructured VDM Received Process Unstructured VDM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : Unstructured VDM Sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 817 Table 8.152, "Steps for Unstructured VDM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.125, "Unstructured VDM Message Sequence" above. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send an Unstructured Vendor_Defined Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. PHY Layer receives the Unstructured Vendor_Defined Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Unstructured Vendor_Defined Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form an Unstructured Vendor_Defined Message. 11 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 12 PHY Layer receives the Unstructured Vendor_Defined Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 818 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 819 8.3.2.17.2 VDEM Figure 8.126, "VDEM Message Sequence" shows an example sequence of an VDEM transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.126 VDEM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send VDEM Start CRCReceive Timer 21 : VDEM 22 : VDEM + CRC 23 : VDEM Check MessageID against local copy Store Copy of MessageID 23 : VDEM Received Evaluate VDEM Reply with the application specific response which can be again a VDEM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send VDEM 11: VDEM 18: VDEM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : VDEM + CRC 16: GoodCRC + CRC 11: VDEM 15: GoodCRC 14: VDEM Received Process VDEM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : VDEM Sent Page 820 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.153, "Steps for VDEM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.126, "VDEM Message Sequence" above. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send a Vendor_Defined_Extended Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Vendor_Defined_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Vendor_Defined_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY LayerPHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form a Vendor_Defined_Extended Message. 11 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 12 PHY Layer receives the Vendor_Defined_Extended Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 821 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP Page 822 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3 State Diagrams 8.3.3.1 Introduction to state diagrams used in Chapter 8 The state diagrams defined in Section 8.3.3, "State Diagrams" are Normative and Shall define the operation of the Power Delivery Policy Engine. Note: These state diagrams are not intended to replace a well written and robust design. Figure 8.127 Outline of States Figure 8.127, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state. If there are also "Actions on exit" a list of actions carried out on exiting the state, then these are listed as well; otherwise, this box is omitted from the state. At the bottom the status of PD is listed:  “Power" which indicates the present output power for a Source Port or input power for a Sink Port.  “PD" which indicates the present Attachment status either "Attached", "Detached", or "unknown". Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&". In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams (e.g., Source Port or Sink Port state diagrams). Figure 8.128, "References to states" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the state and whether the state is a DFP or UFP. It has also been necessary to indicate conditional entry to either Source Port or Sink Port state diagrams. This is achieved by the use of a bulleted list indicating the preconditions (see example in Figure 8.129, "Example of state reference with conditions"). It is also possible that the entry and return states are the same. Figure 8.130, "Example of state reference with the same entry and exit" indicates a state reference where each referenced state corresponds to either the entry state or the exit state. <Name of State> Actions on entry: “List of actions to carry out on entering the state” Power (VI) = “Present power level” PD = “attachment status” Actions on exit: “List of actions to carry out on exiting the state” Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 823 Figure 8.128 References to states Figure 8.129 Example of state reference with conditions Figure 8.130 Example of state reference with the same entry and exit Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the particular state it is referenced. As soon as the state is exited then the timer is no longer active. Where the timers continue to run outside of the state (such as the NoResponseTimer), this is called out in the text. Timeouts of the timers are listed as conditions on state transitions. The SenderResponseTimer is a special case, as it May be stopped and started from outside the states in which it is used. To allow this to be done without over-complicating the state diagrams, the SenderResponseTimer is described with its own state diagram (Figure 8.131, "SenderResponseTimer Policy Engine State Diagram"). The control of this Timer is shared between the Policy Engine and the Chunking Layer. <Name of reference state> (<DFP | UFP>) Hard Reset: • Consumer or Consumer/Provider -> PE_SNK_.... • Provider/Consumer in Source role -> PE_SRC_... <Name of reference state 1> or <Name of reference state 2> (<DFP | UFP>) Page 824 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Conditions listed on state transitions will come from one of three sources and, when there is a conflict, Should be serviced in the following order: 1) Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.). 2) Events triggered within the Policy Engine e.g., timer timeouts. 3) Information and requests coming from the Device Policy Manager relating either to Local Policy, or to other modules which the Device Policy Manager controls such as power supply and USB-C® Port Control. Note: The following state diagrams are not intended to cover all possible corner cases that could be encountered. For example, where an outgoing Message is Discarded, due to an incoming Message by the Protocol Layer (see Section 6.12.2.3, "Protocol Layer Message Reception") it will be necessary for the higher layers of the system to handle a retry of the AMS that was being initiated, after first handling the incoming Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 825 8.3.3.1.1 SenderResponseTimer State Diagram Figure 8.131, "SenderResponseTimer Policy Engine State Diagram" below shows the state diagram for the Policy Engine in a Source Port or a Sink Port. The following sections describe operation in each of the states. Figure 8.131 SenderResponseTimer Policy Engine State Diagram 8.3.3.1.1.1 SRT_Stopped State The SRT_Stopped State Shall be the starting state for the SenderResponseTimer either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall stop incrementing the SR_Timer. The Policy Engine Shall transition to the SRT_Running State:  When the SenderResponseTimer is started from within a Policy Engine state, or  When a Start_SRT is requested from the Chunking Layer. 8.3.3.1.1.2 SRT_Running State On entry to the SRT_Running State the SenderResponseTimer state machine Shall:  Set the SR_Timer to zero  Start running SR_Timer. The SenderResponseTimer state machine Shall transition to the SRT_Expired State:  When the SR_Timer reaches its maximum count The SenderResponseTimer state machine Shall transition to the SRT_Stopped State:  When the SenderResponseTimer is stopped by exiting a Policy Engine state, or  When a Stop_SRT is requested from the Chunking Layer SRT_Stopped Actions on entry: Stop Incrementing SR_Timer1 Power-up | Hard Reset | SenderResponseTimer stopped on exit from Policy Engine State | Stop_SRT requested from Chunking Layer Actions on entry: Zero SR_Timer Start Incrementing SR_Timer1 SRT_Running SenderResponseTimer started from within Policy Engine State | Start_SRT requested from Chunking Layer Actions on entry: Inform Policy Engine of SenderResponseTimer timeout SRT_Expired SR_Timer1 reached maximum count Policy Engine informed 1) The SR_Timer is regarded as the mechanism within the SenderResponseTimer state diagram that implements the SenderResponseTimer. Page 826 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.1.1.3 SRT_Expired State On entry to the SRT_Running State the SenderResponseTimer state machine Shall Inform Policy Engine of SenderResponseTimer timeout The Policy Engine Shall then transition to the SRT_Stopped state:  When the Policy Engine has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 827 8.3.3.2 Policy Engine Source Port State Diagram Figure 8.132, "Source Port State Diagram" below shows the state diagram for the Policy Engine in a Source Port. The following sections describe operation in each of the states. Figure 8.132 Source Port State Diagram 1) Implementation of the CapsCounter is Optional. In the case where this is not implemented the Source Shall continue to send Source_Capabilities Messages each time the SourceCapabilityTimer times out. 2) Since the Sink is required to make a Valid request from the offered capabilities the expected transition is via "Request can be met" unless the Source Capabilities have changed since the last offer. 3) “Contract Invalid" means that the previously Negotiated voltage and Current values are no longer included in the Source's new Capabilities. If the Sink fails to make a Valid Request in this case, then Power Delivery operation is no lon- ger possible and Power Delivery mode is exited with a Hard Reset. Protocol LayerReset4 | SwapSourceStartTimer timeout PE_SRC_Discovery Actions on entry: Initialize and run SourceCapabilityTimer Power = Default (5V) or Implicit Contract PD = not Connected PE_SRC_Ready Actions on entry: Notify Protocol Layer of end of AMS8 Initialize and run DiscoverIdentityTimer7 Initialize and run SourcePPSCommTimer10 Initialize and run SourceEPRKeepAliveTimer11 Power = Explicit Contract PD = Connected PE_SRC_Transition_Supply Actions on entry: Send Accept message (within tReceiverResponse) Request Device Policy Manager to transition Power Supply Power = transition PD = Connected Actions on exit: Send PS_RDY message (In SPR Mode & Request Message) | (In EPR Mode & EPR_Request Message) PE_SRC_Negotiate_Capability Actions on entry: Get Device Policy Manager evaluation of sink request: • Can be met • Can’t be met • Could be met later from Power Reserve If the sink request for Operating Current or Operating Power can be met, but the sink still requires more power (“Capability Mismatch”) this information will be passed to Device Policy Manager4 Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SRC_Capability_Response Actions on entry: Send Reject message if request can’t be met Send Wait message if request could be met later from the Power Reserve and present Contract is still valid Power = DefauIt (5V) or Implicit/ Explicit Contract PD = Connected Start Explicit Contract (Reject message sent & Contract still valid) | Wait message sent PE_SRC_Send_Capabilities Actions on entry: Request present source capabilities from Device Policy Manager In SPR Mode Send Source_Capabilities Message In EPR Mode Send EPR_Source_Capabilities Message Increment CapsCounter (optional)1 If GoodCRC received: • stop NoResponseTimer • reset HardResetCounter and CapsCounter • initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SRC_Hard_Reset Actions on entry: Generate Hard Reset signalling Initialize and start NoResponseTimer Start PSHardResetTimer Increment HardResetCounter Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Request can’t be met | Request met later from Power Reserve Explicit Contract & Reject message sent & Contract Invalid4 PSHardResetTimer timeout Request can be met Power supply ready Power source at default (SourceCapabilityTimer timeout & CapsCounter ” nCapsCount1) Capabilities message sending failure (without GoodCRC) ¬ presently PD Connected6 In SPR Mode Request Message received | In EPR Mode EPR_Request Message received PE_SRC_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager12 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Hard reset signalling received SenderResponseTimer timeout not previously PD Connected6& NoResponseTimer timeout & HardResetCounter > nHardResetCount1 PSHardResetTimer timeout (SourceCapabilityTimer timeout & CapsCounter > nCapsCount1) | (not previously PD Connected6 & NoResponseTimer timeout & HardResetCounter > nHardResetCount1) PE_SRC_Startup Actions on entry: Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer (only after Swap) Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SRC_Transition_to_default Actions on entry: Request Device Policy Manager to request power supply Hard Resets to vSafe5V via vSafe0V Reset local HW Request Device Policy Manager to set Port Data Role to DFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected PE_SRC_Disabled Actions on entry: Disable Power Delivery Power = DefauIt (5V) PD =not Connected Actions on exit: Request Device Policy Manager to turn on VCONN Inform Protocol Layer Hard Reset complete ErrorRecovery previously PD Connected6 & NoResponseTimer timeout & HardResetCount > nHardResetCount PE_SRC_Wait_New_Capabilities Actions on entry: Wait for new Source Capabilities9 Power = DefauIt (5V) PD =Connected PE_SRC_Hard_Reset_Received Actions on entry: Start PSHardResetTimer Initialize and start NoResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Source capability change (from Device Policy Manager) no Explicit Contract & (Reject message sent | Wait message sent) Source capability change (from Device Policy Manager) | (In SPR Mode & Get_Source_Cap Message) | (In EPR Mode & EPR_Get_Source_Cap Message) Protocol Error Actions on exit: If the Source is initiating an AMS then notify the Protocol Layer than the first Message in an AMS will follow8 SourcePPSCommTimer timeout | SourceEPRKeepAliveTimer timeout PE_SRC_EPR_Keep_Alive Actions on entry: Send EPR_Keep_Alive_Ack Message Power = Explicit Contract PD = Connected EPR_Keep_Alive Message EPR_Keep_Alive_Ack Sent Hard Reset request from Device Policy Manager | EPR Mode & Request Message received | EPR Capable & SPR Mode & EPR_Request Message received (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities message sent PE_SRC_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Page 828 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) After a Power Swap the New Source is required to wait an additional tSwapSourceStart before sending a Source_Capabilities Message. This delay is not required when first starting up a system. 5) PD Connected is defined as a situation when the Port Partners are actively communicating. The Port Partners remain PD Connected after a Swap until there is a transition to Disabled or the connector is able to identify a Detach. 6) Port Partners are no longer PD Connected after a Hard Reset, but consideration needs to be given as to whether there has been a PD Connection while the Ports have been Attached to prevent unnecessary USB Type-C Error Recovery. 7) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 8) See Section 5.7, "Collision Avoidance", Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". 9) In the PE_SRC_Wait_New_Capabilities State the Device Policy Manager Should either decide to send no further Source Capabilities or Should send a different set of Source Capabilities. Continuing to send the same set of Source Capabilities could result in a live lock situation. 10) The SourcePPSCommTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sourc- es that do not support SPR PPS do not need to implement the SourcePPSCommTimer. 11) The SourceEPRKeepAliveTimer is only initialized and run when the Source is in EPR Mode; Sources that do not support EPR Mode do not need to implement the SourceEPRKeepAliveTimer. 12) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. 8.3.3.2.1 PE_SRC_Startup State PE_SRC_Startup Shall be the starting state for a Source Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the CapsCounter and reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state:  When the Protocol Layer reset has completed if the PE_SRC_Startup state was entered due to the system first starting up.  When the SwapSourceStartTimer times out if the PE_SRC_Startup state was entered as the result of a Power Role Swap. Note: Sources Shall remain in the PE_SRC_Startup state, without sending any Source_Capabilities Messages until a plug is Attached. 8.3.3.2.2 PE_SRC_Discovery State On entry to the PE_SRC_Discovery state the Policy Engine Shall initialize and run the SourceCapabilityTimer in order to trigger sending a Source_Capabilities Message. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The SourceCapabilityTimer times out and CapsCounter ≤ nCapsCount. The Policy Engine May Optionally go to the PE_SRC_Disabled state when:  The Port Partners are not presently PD Connected  And the SourceCapabilityTimer times out  And CapsCounter > nCapsCount. The Policy Engine Shall go to the PE_SRC_Disabled state when:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 829  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. Note: In the PE_SRC_Disabled state the Attached device is assumed to be unresponsive. The Policy Engine operates as if the device is Detached until such time as a Detach/Re-attach is detected. 8.3.3.2.3 PE_SRC_Send_Capabilities State Note: This state can be entered from the PE_SRC_Soft_Reset state. On entry to the PE_SRC_Send_Capabilities state the Policy Engine Shall request the present Port capabilities from the Device Policy Manager. The Policy Engine Shall then request the Protocol Layer to send a capabilities Message containing these capabilities. The Policy Engine Shall request:  A Source_Capabilities Message if the Source is in SPR Mode or  An EPR_Source_Capabilities Message if the Source is in EPR Mode. The Policy Engine Shall then increment the CapsCounter (if implemented). If a GoodCRC Message is received, then the Policy Engine Shall:  Stop the NoResponseTimer.  Reset the HardResetCounter and CapsCounter to zero. Note: The HardResetCounter Shall only be set to zero in this state and at power up; its value Shall be maintained during a Hard Reset.  Initialize and run the SenderResponseTimer. Once a Source_Capabilities Message has been received and acknowledged by a GoodCRC Message, the Sink is required to then send a Request Message within tSenderResponse. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received from the Sink and the Source is operating in SPR Mode or  An EPR_Request Message is received from the Sink and the Source is operating in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Discovery state when:  The Protocol Layer indicates that the Message has not been sent and we are presently not Connected. This is part of the Capabilities sending process whereby successful Message sending indicates connection to a PD Sink Port. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The SenderResponseTimer times out. In this case a transition back to USB Default Operation is required. When:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment)  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. The Policy Engine Shall do one of the following:  Transition to the PE_SRC_Discovery state.  Transition to the PE_SRC_Disabled state. Page 830 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: That in either case the Attached device is assumed to be unresponsive. The Policy Engine Should operate as if the device is Detached until such time as a Detach/Re-attach is detected. The Policy Engine Shall go to the ErrorRecovery state when:  The Port Partners have previously been PD Connected (the Source Port remains Attached to a Port it has had a PD Connection with during this Attachment)  And the NoResponseTimer times out.  And the HardResetCounter > nHardResetCount. 8.3.3.2.4 PE_SRC_Negotiate_Capability State On entry to the PE_SRC_Negotiate_Capability state the Policy Engine Shall ask the Device Policy Manager to evaluate the Request from the Attached Sink. The response from the Device Policy Manager Shall be one of the following:  The Request can be met.  The Request cannot be met  The Request could be met later from the Power Reserve. The Policy Engine Shall transition to the PE_SRC_Transition_Supply state when:  The Request can be met. The Policy Engine Shall transition to the PE_SRC_Capability_Response state when:  The Request cannot be met.  Or the Request can be met later from the Power Reserve. 8.3.3.2.5 PE_SRC_Transition_Supply State The Policy Engine Shall be in the PE_SRC_Transition_Supply state while the power supply is transitioning from one power to another. On entry to the PE_SRC_Transition_Supply state, the Policy Engine Shall request the Protocol Layer to send an Accept Message and inform the Device Policy Manager that it Shall transition the power supply to the Requested power level. Note: If the power supply is currently operating at the requested power no change will be necessary. On exit from the PE_SRC_Transition_Supply state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The Device Policy Manager informs the Policy Engine that the power supply is ready. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.2.6 PE_SRC_Ready State In the PE_SRC_Ready state the PD Source Shall be operating at a stable power with no ongoing Negotiation. It Shall respond to requests from the Sink, events from the Device Policy Manager. On entry to the PE_SRC_Ready state the Source Shall notify the Protocol Layer of the end of the Atomic Message Sequence (AMS). If the transition into PE_SRC_Ready is the result of Protocol Error that has not caused a Soft Reset (see Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram") then the notification to the Protocol Layer of the end of the AMS Shall Not be sent since there is a Message to be processed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 831 On entry to the PE_SRC_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, the Policy Engine Shall:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). On entry to the PE_SRC_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SourcePPSCommTimer. On entry to the PE_SRC_Ready state if the current Explicit Contract is for EPR Mode, then the Policy Engine Shall do the following:  Initialize and run the SourceEPRKeepAliveTimer. On exit from the PE_SRC_Ready, if the Source is initiating an AMS, then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed or  A Get_Source_Cap Message is received, and the Source is in SPR Mode or  An EPR_Get_Source_Cap Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received, and the Source is in SPR Mode or  An EPR_Request Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap state when:  The Device Policy Manager asks for the Sink Capabilities. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Source is operating as an SPR PPS and the SourcePPSCommTimer Timer times-out or  The Source is in EPR Mode and the SourceEPRKeepAliveTimer Timer times-out. The Policy Engine Shall transition to the PE_SRC_EPR_Keep_Alive state when:  An EPR_KeepAlive Message is received. The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap State when:  In EPR Mode and a Get_Source_Cap Message is received or  In SPR Mode and an EPR_Get_Source_Cap Message is received. 8.3.3.2.7 PE_SRC_Disabled State In the PE_SRC_Disabled state the PD Source supplies default power and is unresponsive to USB Power Delivery messaging, but not to Hard Reset Signaling. 8.3.3.2.8 PE_SRC_Capability_Response State The Policy Engine Shall enter the PE_SRC_Capability_Response state if there is a Request received from the Sink that cannot be met based on the present capabilities. When the present Explicit Contract is not within the present capabilities it is regarded as Invalid and a Hard Reset will be triggered. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall request the Protocol Layer to send one of the following: Page 832 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Reject Message - if the request cannot be met or the present Explicit Contract is Invalid.  Wait Message - if the request could be met later from the Power Reserve. A Wait Message Shall Not be sent if the present Explicit Contract is Invalid. The Policy Engine Shall transition to the PE_SRC_Ready state when:  There is an Explicit Contract and  A Reject Message has been sent and the present Explicit Contract is still Valid or  A Wait Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  There is an Explicit Contract and  The Reject Message has been sent and the present Explicit Contract is Invalid (i.e., the Sink had to request a new value so instead we will return to USB Default Operation). The Policy Engine Shall transition to the PE_SRC_Wait_New_Capabilities state when:  There is no Explicit Contract and  A Reject Message has been sent or  A Wait Message has been sent. 8.3.3.2.9 PE_SRC_Hard_Reset State The Policy Engine Shall transition to the PE_SRC_Hard_Reset state from any state when:  Hard Reset request from Device Policy Manager or  In EPR Mode and a Request Message is received or  EPR Capable and in SPR Mode and an EPR_Request Message is received. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall:  request the generation of Hard Reset Signaling by the PHY Layer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out.  initialize and run the PSHardResetTimer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when:  The PSHardResetTimer times out. 8.3.3.2.10 PE_SRC_Hard_Reset_Received State The Policy Engine Shall transition from any state to the PE_SRC_Hard_Reset_Received state when:  Hard Reset Signaling is detected. On entry to the PE_SRC_Hard_Reset_Received state the Policy Engine Shall:  initialize and run the PSHardResetTimer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 833  The PSHardResetTimer times out. 8.3.3.2.11 PE_SRC_Transition_to_default State On entry to the PE_SRC_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the power supply Shall Hard Reset (see Section 7.1.5, "Response to Hard Resets").  request a reset of the local hardware  request the Device Policy Manager to set the Port Data Role to DFP and turn off VCONN. On exit from the PE_SRC_Transition_to_default state the Policy Engine Shall:  request the Device Policy Manager to turn on VCONN  inform the Protocol Layer that the Hard Reset is complete. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Device Policy Manager indicates that the power supply has reached the default level. 8.3.3.2.12 PE_SRC_Get_Sink_Cap State In this state the Policy Engine, due to a request from the Device Policy Manager, Shall request the capabilities from the Attached Sink. On entry to the PE_SRC_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SRC_Ready state when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. 8.3.3.2.13 PE_SRC_Wait_New_Capabilities State In this state the Policy Engine has been unable to Negotiate an Explicit Contract and is waiting for new Capabilities from the Device Policy Manager. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed. 8.3.3.2.14 PE_SRC_EPR_Keep_Alive State On entry to the PE_SRC_EPR_Keep_Alive State the Policy Engine Shall send a EPR_KeepAlive_Ack Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_KeepAlive_Ack Message has been sent. Page 834 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.2.15 8.3.3.2.15PE_SRC_Give_Source_Cap State  On entry to the PE_SRC_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Source Capabilities Message has been successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 835 8.3.3.3 Policy Engine Sink Port State Diagram Figure 8.133, "Sink Port State Diagram" below shows the state diagram for the Policy Engine in a Sink Port. The following sections describe operation in each of the states. Figure 8.133 Sink Port State Diagram 1) Source Capabilities Messages received in States other than PE_SNK_Wait_for_Capabilities, PE_SNK_Ready or PE_SNK_Get_Source_Cap constitute a Protocol Error. 2) The SinkRequestTimer Should Not be stopped if a Ping (Deprecated) Message is received in the PE_SNK_Ready state since it represents the maximum time between requests after a Wait Message which is not reset by a Ping (Deprecat- ed) Message. 3) During a Hard Reset the Source voltage will transition to vSafe0V and then transition to vSafe5V. Sinks need to ensure that VBUS present is not indicated until after the Source has completed the Hard Reset process by detecting both of these transitions. New power required | SinkRequestTimer Timeout | SinkPPSPeriodicTimer Timeout Start Explicit Contract & (Reject message received | Wait message received) Hard reset signalling received Power Sink at default Protocol Layer Reset Hard Reset complete VBUS 6 present3 ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source_Capabilities Message received))1 Device Policy Manager Response received Accept message received PS_RDY message received Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink capabilities message sent ((SinkWaitCapTimer timeout | PSTransitionTimer timeout) & (HardResetCounter ” nHardResetCount)) | Hard Reset request from Device Policy Manager | EPR Mode & (EPR_Source _Capabilites message with An EPR PDO in positions 1..7 | Source_Capabilities Message not requested by Get_Source_caps) PE_SNK_Startup Actions on entry: Reset Protocol Layer Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected SenderResponseTimer Timeout PE_SNK_Discovery Actions on entry: Wait for VBUS 6 Power = Default (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Wait_for_Capabilities Actions on entry: Initialize and run SinkWaitCapTimer Power = Default (5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Evaluate_Capability Actions on entry: Reset HardResetCounter to zero. Ask Device Policy Manager to evaluate the options based on supplied capabilities, any Power Reserve that it needs, and respond indicating the selected capability and, Optionally, a “Capability Mismatch”. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Select_Capability Actions on entry: Send Request based on Device Policy Manager response: • Request from present capabilities • Optionally Indicate that other capabilities would be preferred (“Capability Mismatch”) Initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Transition_Sink Actions on entry: Initialize and run PSTransitionTimer Power = transition PD = Connected Actions on exit: Request Device Policy Manager transitions sink power supply to new power (if required) PE_SNK_Ready Actions on entry: Initialize and run SinkRequestTimer2 (on receiving Wait) Initialize and run DiscoverIdentityTimer4 Initialize and run the SinkPPSPeriodicTimer5 In EPR Mode Initialize and run the SinkEPRKeepAliveTimer8 If Sink supports Fast Role Swap send Get_Sink_Cap Message7 Power = Explicit Contract PD = Connected PE_SNK_Give_Sink_Cap Actions on entry: Get present sink capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected PE_SNK_Hard_Reset Actions on entry: Generate Hard Reset signalling. Increment HardResetCounter. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SNK_Transition_to_default Actions on entry: Request Device Policy Manager to request power sink transition to default Reset local HW Set Port Data Role to UFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected Actions on exit: Inform Protocol Layer Hard Reset complete no Explicit Contract & (Reject message received | Wait message received) ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source Capabilities Message))1 Actions on exit: If the Sink is initiating an AMS then notify the Protocol Layer that the first Message in the AMS will follow. Protocol Error PE_SNK_EPR_Keep_Alive Actions on entry: Send EPR_KeepAlive Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected SinkEPRKeepAliveTimer Timeout EPR_KeepAlive_Ack Message SenderResponseTimer Timeout PE_SNK_Get_Source_Cap Actions on entry: If SPR Mode capabilities requested send Get_Source_Cap Message If EPR Mode capabilities requested send EPR_Get_Source_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get source capabilities request from Device Policy Manager (EPR Mode & SPR Source Capabilities requested & Source_Capabilities Message received) | (SPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message received) | SenderResponseTimer timeout Actions on exit: Pass Source capabilities/outcome to Device Policy Manager (SPR Mode & SPR Source Capabilities requested & Source_Capabilities Message) | (EPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message) Page 836 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 5) The SinkPPSPeriodicTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sinks that do not support PPS do not need to implement the SinkPPSPeriodicTimer. 6) A Sink that is a VPD May use VCONN as a proxy for VBUS. 7) To be sent once, and only required if Fast Role Swap is supported by the Sink. 8.3.3.3.1 PE_SNK_Startup State PE_SNK_Startup Shall be the starting state for a Sink Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). Once the reset process completes, the Policy Engine Shall transition to the PE_SNK_Discovery state. 8.3.3.3.2 PE_SNK_Discovery State In the PE_SNK_Discovery state the Sink Policy Engine waits for VBUS to be present. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Device Policy Manager indicates that VBUS has been detected. 8.3.3.3.3 PE_SNK_Wait_for_Capabilities State On entry to the PE_SNK_Wait_for_Capabilities state the Policy Engine Shall initialize and start the SinkWaitCapTimer. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  The Sink is in SPR Mode and a Source_Capabilities Message is received or  The Sink is in EPR Mode and an EPR_Source_Capabilities Message is received. When the SinkWaitCapTimer times out, the Policy Engine will perform a Hard Reset. 8.3.3.3.4 PE_SNK_Evaluate_Capability State The PE_SNK_Evaluate_Capability state is first entered when the Sink receives its first Source_Capabilities Message from the Source. At this point the Sink knows that it is Attached to and communicating with a PD capable Source. On entry to the PE_SNK_Evaluate_Capability state the Policy Engine Shall request the Device Policy Manager to evaluate the supplied Source Capabilities based on Local Policy. The Device Policy Manager Shall indicate to the Policy Engine the new power level required, selected from the present offered capabilities. The Device Policy Manager Shall also indicate to the Policy Engine a Capabilities Mismatch if the offered power does not meet the device's requirements. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A response is received from the Device Policy Manager. 8.3.3.3.5 PE_SNK_Select_Capability State On entry to the PE_SNK_Select_Capability state the Policy Engine Shall request the Protocol Layer to send a response Message, based on the evaluation from the Device Policy Manager. The Message Shall be one of the following:  A Request from the offered Source Capabilities. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 837  A Request from the offered Source Capabilities with an indication that another power level would be preferred (Capability Mismatch bit set). When in SPR Mode a Request Message Shall be sent. When in EPR Mode an EPR_Request Message Shall be sent. The Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Transition_Sink state when:  An Accept Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  There is no Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Ready state when:  There is an Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs. 8.3.3.3.6 PE_SNK_Transition_Sink State On entry to the PE_SNK_Transition_Sink state the Policy Engine Shall initialize and run the PSTransitionTimer (timeout will lead to a Hard Reset see Section 8.3.3.3.8, "PE_SNK_Hard_Reset State" and Shall then request the Device Policy Manager to transition the Sink's power supply to the new power level. Note: If there is no power level change the Device Policy Manager Should Not affect any change to the power supply. On exit from the PE_SNK_Transition_Sink state the Policy Engine Shall request the Device Policy Manager to transition the Sink's power supply to the new power level. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A PS_RDY Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.3.7 PE_SNK_Ready State In the PE_SNK_Ready state the PD Sink Shall be operating at a stable power level with no ongoing Negotiation. It Shall respond to requests from the Source, events from the Device Policy Manager. On entry to the PE_SNK_Ready state as the result of a wait the Policy Engine Should do the following:  Initialize and run the SinkRequestTimer. On entry to the PE_SNK_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, then the Policy Engine Shall do the following:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). Page 838 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SinkPPSPeriodicTimer. On entry to the PE_SNK_Ready state if the Sink supports Fast Role Swap, then the Policy Engine Shall do the following:  Send a Get_Sink_Cap Message. On exit from the PE_SNK_Ready state, if the transition is as a result of a DPM request to start a new Atomic Message Sequence (AMS) then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  In SPR Mode and a Source_Capabilities Message is received or  In EPR Mode and an EPR_Source_Capabilities Message is received. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A new power level is requested by the Device Policy Manager or  A SinkRequestTimer timeout occurs or  A SinkPPSPeriodicTimer timeout occurs. The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap state when:  Get_Sink_Cap Message is received or  EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap state when:  The Device Policy Manager requests an update of the remote Source Capabilities. The Policy Engine Shall transition to the PE_SNK_EPR_Keep_Alive state when:  The SinkEPRKeepAliveTimer timeouts out. 8.3.3.3.8 PE_SNK_Hard_Reset State The Policy Engine Shall transition to the PE_SNK_Hard_Reset state from any state when:  (PSTransitionTimer times out) and  (HardResetCounter ≤ nHardResetCount)) |  Hard Reset request from Device Policy Manager or  In EPR Mode and  An EPR_Source_Capabilities Message is received with an EPR (A)PDO in object positions 1…7 or  A Source_Capabilities Message is received that has not been requested using a Get_Source_Cap Message. The Policy Engine May transition to the PE_SNK_Hard_Reset state from any state when:  SinkWaitCapTimer times out Note: If the SinkWaitCapTimer times out and the HardResetCounter is greater than nHardResetCount the Sink Shall assume that the Source is non-responsive. Note: The HardResetCounter is reset on a power cycle or Detach. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 839 On entry to the PE_SNK_Hard_Reset state the Policy Engine Shall request the generation of Hard Reset Signaling by the PHY Layer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SNK_Transition_to_default state when:  The Hard Reset is complete. 8.3.3.3.9 PE_SNK_Transition_to_default State The Policy Engine Shall transition from any state to PE_SNK_Transition_to_default state when:  Hard Reset Signaling is detected. When Hard Reset Signaling is received or transmitted then the Policy Engine Shall transition from any state to PE_SNK_Transition_to_default. This state can also be entered from the PE_SNK_Hard_Reset state. On entry to the PE_SNK_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the Sink Shall transition to default  request a reset of the local hardware  request the Device Policy Manager that the Port Data Role is set to UFP. The Policy Engine Shall transition to the PE_SNK_Startup state when:  The Device Policy Manager indicates that the Sink has reached the default level. 8.3.3.3.10 PE_SNK_Give_Sink_Cap State  On entry to the PE_SNK_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Sink_Capabilities Message has been successfully sent. 8.3.3.3.11 PE_SNK_EPR_Keep_Alive On entry to the PE_SNK_EPR_Keep_Alive State the Policy Engine Shall send an EPR_KeepAlive Message and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A EPR_KeepAlive_Ack Message is received. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The SenderResponseTimer times out. 8.3.3.3.12 PE_SNK_Get_Source_Cap State  On entry to the PE_SNK_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. Page 840 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On exit from the PE_SNK_Get_Source_Cap State the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SNK_Ready state when:  In EPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In SPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability State when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 841 8.3.3.4 SOP Soft Reset and Protocol Error State Diagrams 8.3.3.4.1 SOP Source Port Soft Reset and Protocol Error State Diagram Figure 8.134, "SOP Source Port Soft Reset and Protocol Error State Diagram" below shows the state diagram for the Policy Engine in a Source Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.134 SOP Source Port Soft Reset and Protocol Error State Diagram 8.3.3.4.1.1 PE_SRC_Send_Soft_Reset State The PE_SRC_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during a Non-interruptible AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response or  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  The Source is in the PE_SRC_Send_Capabilities state, there is a Source_Capabilities Message sending failure on SOP (without a GoodCRC Message) and the Source is not presently Attached (as indicated in Figure 8.132, "Source Port State Diagram"). In this case, the PE_SRC_Discovery state is entered (see Section 8.3.3.2.2, "PE_SRC_Discovery State").  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.2, "Policy Engine Source Port State Diagram"). In this case Hard Reset Signaling will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case USB Type-C Error Recovery will be triggered directly.  During a Data Role Swap when there is a mismatch in the Port Data Role field (see Section 6.2.1.1.6, "Port Data Role"). In this case USB Type-C Error Recovery will be triggered directly. PE_SRC_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept message Received from SOP Accept message Sent to SOP Soft Reset message Received on SOP PE_SRC_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SRC_Send_Capabilities Transmission Error indication from Protocol Layer PE_SRC_Ready In Explicit Contract & Protocol Error2 before first Message in AMS sent (no GoodCRC received) PE_SRC_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message received on SOP will result in a Not_Supported Message response being generated on SOP (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Source during the EPR Mode entry process. Page 842 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SRC_Ready state where the Message received will be handled as if it had been received in the PE_SRC_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. On entry to the PE_SRC_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message to the Sink on SOP, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.1.2 PE_SRC_Soft_Reset State The PE_SRC_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SRC_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state (see Section 8.3.3.2.3, "PE_SRC_Send_Capabilities State") when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 843 8.3.3.4.2 SOP Sink Port Soft Reset and Protocol Error State Diagram Figure 8.135, "Sink Port Soft Reset and Protocol Error Diagram" below shows the state diagram for the Policy Engine in a Sink Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.135 Sink Port Soft Reset and Protocol Error Diagram 8.3.3.4.2.1 PE_SNK_Send_Soft_Reset State The PE_SNK_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during an AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response.  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). In this case a Hard Reset will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case a Hard Reset will be triggered directly.  During a Data Role Swap when the DFP/UFP Data Roles are changing. In this case USB Type-C Error Recovery will be triggered directly. Note: Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SNK_Ready state where the Message received will be handled as if it had been received in the PE_SNK_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. PE_SNK_Send_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Soft Reset Message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept Message Received on SOP Accept Message Sent to SOP Soft Reset Message Received on SOP PE_SNK_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Accept Message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SNK_Wait_for_Capabilities Transmission Error indication from Protocol Layer PE_SNK_Ready In Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message will result in a Not_Supported Message response being generated (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Sink during the EPR Mode entry process. Page 844 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP to the Source, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.2.2 PE_SNK_Soft_Reset State The PE_SNK_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SNK_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 845 8.3.3.5 Data Reset State Diagrams 8.3.3.5.1 DFP Data_Reset Message State Diagrams Figure 8.136, "DFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a DFP. Figure 8.136 DFP Data_Reset Message State Diagram 8.3.3.5.1.1 PE_DDR_Send_Data_Reset State The PE_DDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_DDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and start the SenderResponseTimer. On exit from the PE_DDR_Send_Data_Reset State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been received and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been received and PE_DDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and start SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_DDR_Wait_for_VCONN_Off Actions on entry: Initialize and start VCONNDischargeTimer Power = Explicit Contract PD = connected Accept Message Received & Not VCONN Source VCONNDischargeTimer Timeout | Protocol Error PS_RDY Received PE_DDR_Perform_Data_Reset Actions on entry: Tell Device Policy Manager to perform Data Reset Power = Explicit Contract PD = connected PE_SRC_Ready or PE_SNK_Ready (DFP) Data Reset process is complete Accept Message Sent & Not VCONN Source Protocol Error DataResetFailTimer Timeout | Protocol Error Actions on exit: Stop DataResetFailTimer Send Data_Reset_Complete Message Actions on exit: Initialize and start DataResetFailTimer1 Actions on exit: Initialize and start DataResetFailTimer1 1) Note that the DataResetFailTimer Shall continue to run in every state until it is stopped or times out. Page 846 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A SenderResponseTimer timeout occurs or  A Protocol Error occurs. 8.3.3.5.1.2 PE_DDR_Data_Reset_Received State The PE_DDR_Data_Reset_Received State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_DDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_DDR_Data_Reset_Received State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been sent and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been sent and  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.1.3 PE_DDR_Wait_For_VCONN_Off State On entry to the PE_DDR_Wait_For_VCONN_Off State the Policy Engine Shall initialize and start the VCONNDischargeTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  A PS_RDY Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The VCONNDischargeTimer has timed out or  A Protocol Error occurs. 8.3.3.5.1.4 PE_DDR_Perform_Data_Reset State On entry to the PE_DDR_Perform_Data_Reset State the Policy Engine Shall request the Device Policy Manager to complete the Data Reset process as defined in Section 6.3.14, "Data_Reset Message". On exit from the PE_DDR_Perform_Data_Reset State the Policy Engine Shall stop the DataResetFailTimer and send a Data_Reset_Complete Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the DFP's Power Role when:  The DPM indicates that Data Reset process is complete (see Section 6.3.14, "Data_Reset Message"). The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailTimer times out  A Protocol Error occurs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 847 8.3.3.5.2 UFP Data_Reset Message State Diagrams Figure 8.137, "UFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a UFP. Figure 8.137 UFP Data_Reset Message State Diagram 8.3.3.5.2.1 PE_UDR_Send_Data_Reset State The PE_UDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_UDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and run the SenderResponseTimer. On exit from the PE_UDR_Send_Data_Reset State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been received and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been received and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when: PE_UDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (UFP) PE_UDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_UDR_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = connected PE_UDR_Send_Ps_Rdy Actions on entry: Send PS_RDY Message Power = Explicit Contract PD = connected VCONN Off1 PE_SRC_Ready or PE_SNK_Ready (UFP) Accept Message Received & Not VCONN Source PS_RDY Message Sent Accept Message Sent & Not VCONN Source Protocol Error PE_UDR_Wait_For_Data_Reset_Complete Actions on entry: Wait for Data_Reset_Complete Message Power = Explicit Contract PD = connected Data_Reset_Complete Message received Protocol Error Protocol Error DataResetFailUFPTimer Timeout2 | Protocol Error Actions on exit: Stop DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 1) VCONN Shall be fully discharged see Section 7.1.15 “Vconn Power Cycle”. 2) Note that the DataResetFailUFPTimer Shall continue to run in every state until it is stopped or times out. Page 848 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The SenderResponseTimer has timed out or  A Protocol Error occurs. 8.3.3.5.2.2 PE_UDR_Data_Reset_Received State The PE_UDR_Data_Reset_Received State Shall be entered from either the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_UDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_UDR_Data_Reset_Received State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been sent and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been sent and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.3 PE_UDR_Turn_Off_VCONN State On entry to the PE_UDR_Turn_Off_VCONN State the Policy Engine Shall request the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition to the PE_UDR_Send_Ps_Rdy State when:  The DPM indicates that VCONN has been turned off (VCONN below vRaReconnect see [USB Type-C 2.4]). The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.4 PE_UDR_Send_Ps_Rdy State On entry to the PE_UDR_Send_Ps_Rdy State the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.5 PE_UDR_Wait_For_Data_Reset_Complete State On entry to the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall wait for the Data_Reset_Complete Message. On exit from the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall stop the DataResetFailUFPTimer. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the UFP's Power Role when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 849  The Data_Reset_Complete Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailUFPTimer times out or  A Protocol Error occurs. Page 850 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6 Not Supported Message State Diagrams 8.3.3.6.1 Source Port Not Supported Message State Diagram Figure 8.138, "Source Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Source Port. Figure 8.138 Source Port Not Supported Message State Diagram 8.3.3.6.1.1 PE_SRC_Send_Not_Supported State The PE_SRC_Send_Not_Supported state Shall be entered from the PE_SRC_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SRC_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SRC_Send_Not_Supported state (from the PE_SRC_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.1.2 PE_SRC_Not_Supported_Received State The PE_SRC_Not_Supported_Received state Shall be entered from the PE_SRC_Ready state when a Not_Supported Message is received. On entry to the PE_SRC_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.1.3 PE_SRC_Chunk_Received State The PE_SRC_Chunk_Received state Shall be entered from the PE_SRC_Ready state as a result of an Unsupported Message being received in the PE_SRC_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). PE_SRC_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SRC_Ready PE_SRC_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SRC_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SRC_Ready state directly (see also Section 8.3.3.4.1 “SOP Source Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 851 On entry to the PE_SRC_Chunk_Received state (from the PE_SRC_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SRC_Send_Not_Supported when:  The ChunkingNotSupportedTimer has timed out. Page 852 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6.2 Sink Port Not Supported Message State Diagram Figure 8.139, "Sink Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Sink Port. Figure 8.139 Sink Port Not Supported Message State Diagram 8.3.3.6.2.1 PE_SNK_Send_Not_Supported State The PE_SNK_Send_Not_Supported state Shall be entered from the PE_SNK_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SNK_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Send_Not_Supported state (from the PE_SNK_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.2.2 PE_SNK_Not_Supported_Received State The PE_SNK_Not_Supported_Received state Shall be entered from the PE_SNK_Ready state when a Not_Supported Message is received. On entry to the PE_SNK_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.2.3 PE_SNK_Chunk_Received State The PE_SNK_Chunk_Received state Shall be entered from the PE_SNK_Ready state as a result of an Unsupported Message being received in the PE_SNK_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Chunk_Received state (from the PE_SNK_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SNK_Send_Not_Supported when: PE_SNK_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SNK_Ready PE_SNK_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SNK_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SNK_Ready state directly (see also Section 8.3.3.4.2 “SOP Sink Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 853  The ChunkingNotSupportedTimer has timed out. Page 854 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7 Alert State Diagrams 8.3.3.7.1 Source Port Source Alert State Diagram Figure 8.140, "Source Port Source Alert State Diagram" shows the state diagram for an Alert Message sent by a Source Port. Figure 8.140 Source Port Source Alert State Diagram 8.3.3.7.1.1 PE_SRC_Send_Source_Alert State The PE_SRC_Send_Source_Alert state Shall be entered from the PE_SRC_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SRC_Send_Source_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SRC_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.1.2 PE_SRC_Wait_for_Get_Status State On entry to the PE_SRC_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The SenderResponseTimer times out. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 855 8.3.3.7.2 Sink Port Source Alert State Diagram Figure 8.141, "Sink Port Source Alert State Diagram" shows the state diagram for an Alert Message received by a Sink Port. Figure 8.141 Sink Port Source Alert State Diagram 8.3.3.7.2.1 PE_SNK_Source_Alert_Received State The PE_SNK_Source_Alert_Received state Shall be entered from the PE_SNK_Ready state when an Alert Message is received. On entry to the PE_SNK_Source_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SNK_Ready State (see Figure 8.133, "Sink Port State Diagram") when:  The DPM does not request status. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Page 856 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7.3 Sink Port Sink Alert State Diagram Figure 8.142, "Sink Port Sink Alert State Diagram" shows the state diagram for an Alert Message sent by a Sink Port. Figure 8.142 Sink Port Sink Alert State Diagram 8.3.3.7.3.1 PE_SNK_Send_Sink_Alert State The PE_SNK_Send_Sink_Alert state Shall be entered from the PE_SNK_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SNK_Send_Sink_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SNK_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.3.2 PE_SNK_Wait_for_Get_Status State On entry to the PE_SNK_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to the PE_SNK_Ready (see Figure 8.133, "Sink Port State Diagram") when:  The SenderResponseTimer times out. PE_SNK_Send_Sink_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Sink alert condition Alert Message sent PE_SNK_Ready SenderResponseTimer Timeout PE_SNK_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 857 8.3.3.7.4 Source Port Sink Alert State Diagram Figure 8.143, "Source Port Sink Alert State Diagram" shows the state diagram for an Alert Message received by a Source Port. Figure 8.143 Source Port Sink Alert State Diagram 8.3.3.7.4.1 PE_SRC_Sink_Alert_Received State The PE_SRC_Sink_Alert_Received state Shall be entered from the PE_SRC_Ready state when an Alert Message is received. On entry to the PE_SRC_Sink_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The DPM does not request status. PE_SRC_Sink_Alert_Received Actions on entry: Inform DPM of the detail of the alert Power = Explicit Contract PD = connected Sink Alert Message received DPM does not request status PE_SRC_Ready PE_Get_Status DPM Requests Status Page 858 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8 Source/Sink Capabilities Extended State Diagrams 8.3.3.8.1 Sink Port Get Source Capabilities Extended State Diagram Figure 8.144, "Sink Port Get Source Capabilities Extended State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.144 Sink Port Get Source Capabilities Extended State Diagram 8.3.3.8.1.1 PE_SNK_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 859 8.3.3.8.2 Source Give Source Capabilities Extended State Diagram Figure 8.145, "Source Give Source Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.145 Source Give Source Capabilities Extended State Diagram 8.3.3.8.2.1 PE_SRC_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_SRC_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SRC_Ready PE_SRC_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 860 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8.3 Source Port Get Sink Capabilities Extended State Diagram Figure 8.146, "Source Port Get Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.146 Source Port Get Sink Capabilities Extended State Diagram 8.3.3.8.3.1 PE_SRC_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Sink_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_SRC_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass sink extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 861 8.3.3.8.4 Sink Give Sink Capabilities Extended State Diagram Figure 8.147, "Sink Give Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.147 Sink Give Sink Capabilities Extended State Diagram 8.3.3.8.4.1 PE_SNK_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_SNK_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Sink_Capabilities_Extended Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SNK_Ready PE_SNK_Give_Sink_Cap_Ext Actions on entry: Get present extended Sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 862 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.9 Source Information State Diagrams 8.3.3.9.1 Sink Port Get Source Information State Diagram Figure 8.148, "Sink Port Get Source Information State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.148 Sink Port Get Source Information State Diagram 8.3.3.9.1.1 PE_SNK_Get_Source_Info State The Policy Engine Shall transition to the PE_SNK_Get_Source_Info state, from the PE_SNK_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Info Message is received  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 863 8.3.3.9.2 Source Give Source Information State Diagram Figure 8.149, "Source Give Source Information State Diagram" shows the state diagram for a Source on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.149 Source Give Source Information State Diagram 8.3.3.9.2.1 PE_SRC_Give_Source_Info State The Policy Engine Shall transition to the PE_SRC_Give_Source_Info state, from the PE_SRC_Ready state, when a Get_Source_Info Message is received. On entry to the PE_SRC_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SRC_Ready PE_SRC_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 864 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10 Status State Diagrams 8.3.3.10.1 Get Status State Diagram Figure 8.150, "Get Status State Diagram" shows the state diagram for a Port on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Status. See also Section 6.5.2, "Status Message". Figure 8.150 Get Status State Diagram 8.3.3.10.1.1 PE_Get_Status State The Policy Engine Shall transition to the PE_Get_Status state, from the PE_SRC_Ready or PE_SNK_Ready States, due to a request to get the Port Partner or Cable Plug's status from the Device Policy Manager. On entry to the PE_Get_Status state the Policy Engine Shall send a Get_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram" or Figure 8.133, "Sink Port State Diagram") when:  A Status Message is received  Or SenderResponseTimer times out. get status request from Device Policy Manager Status Message received | SenderResponseTimer Timeout PE_SNK_Ready, PE_SRC_Ready PE_Get_Status Actions on entry: Send Get_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 865 8.3.3.10.2 Give Status State Diagram Figure 8.151, "Give Status State Diagram" shows the state diagram for a Source on receiving a Get_Status Message. See also Section 6.5.2, "Status Message". Figure 8.151 Give Status State Diagram 8.3.3.10.2.1 PE_Give_Status State The Policy Engine Shall transition to the PE_Give_Status state, from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States, when a Get_Status Message is received. On entry to the PE_Give_Status state the Policy Engine Shall request the present Source status from the Device Policy Manager and then send a Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram"and Figure 8.203, "Cable Ready State Diagram") when:  The Status Message has been successfully sent. Get_Status Message received Status Message sent PE_SRC_Ready, PE_SNK_Ready, PE_CBL_Ready PE_Give_Status Actions on entry: Get present Status from Device Policy Manager Send Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 866 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10.3 Sink Port Get Source PPS Status State Diagram Figure 8.152, "Sink Port Get Source PPS Status State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source status when operating as a PPS. See also Section 6.5.10, "PPS_Status Message". Figure 8.152 Sink Port Get Source PPS Status State Diagram 8.3.3.10.3.1 PE_SNK_Get_PPS_Status State The Policy Engine Shall transition to the PE_SNK_Get_PPS_Status state, from the PE_SNK_Ready state, due to a request to get the remote Source PPS status from the Device Policy Manager. On entry to the PE_SNK_Get_PPS_Status state the Policy Engine Shall send a Get_PPS_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_PPS_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A PPS_Status Message is received  Or SenderResponseTimer times out. get PPS status request from Device Policy Manager PPS_Status Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_PPS_Status Actions on entry: Send Get_PPS_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 867 8.3.3.10.4 Source Give Source PPS Status State Diagram Figure 8.153, "Source Give Source PPS Status State Diagram" shows the state diagram for a Source on receiving a Get_PPS_Status Message. See also Section 6.5.10, "PPS_Status Message". Figure 8.153 Source Give Source PPS Status State Diagram 8.3.3.10.4.1 PE_SRC_Give_PPS_Status State The Policy Engine Shall transition to the PE_SRC_Give_PPS_Status state, from the PE_SRC_Ready state, when a Get_PPS_Status Message is received. On entry to the PE_SRC_Give_PPS_Status state the Policy Engine Shall request the present Source PPS status from the Device Policy Manager and then send a PPS_Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The PPS_Status Message has been successfully sent. Get_PPS_Status Message received PPS_Status Message sent PE_SRC_Ready PE_SRC_Give_PPS_Status Actions on entry: Get present Source PPS status from Device Policy Manager Send PPS_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 868 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.11 Battery Capabilities State Diagrams 8.3.3.11.1 Get Battery Capabilities State Diagram Figure 8.154, "Get Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery capabilities for a specified Battery. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.154 Get Battery Capabilities State Diagram 8.3.3.11.1.1 PE_Get_Battery_Cap State The Policy Engine Shall transition to the PE_Get_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery capabilities, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Cap state the Policy Engine Shall send a Get_Battery_Cap Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Capabilities Message is received  Or SenderResponseTimer times out. get Battery capabilities request from Device Policy Manager Battery_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Cap Actions on entry: Send Get_Battery_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 869 8.3.3.11.2 Give Battery Capabilities State Diagram Figure 8.155, "Give Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Cap Message. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.155 Give Battery Capabilities State Diagram 8.3.3.11.2.1 PE_Give_Battery_Cap State The Policy Engine Shall transition to the PE_Give_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Cap Message is received. On entry to the PE_Give_Battery_Cap state the Policy Engine Shall request the present Battery capabilities, for the requested Battery, from the Device Policy Manager and then send a Battery_Capabilities Message based on these capabilities. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Capabilities Message has been successfully sent. Get_Battery_Cap Message received Battery_Capabilities Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Cap Actions on entry: Get present Battery capabilities from Device Policy Manager Send Battery_Capabilities Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 870 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.12 Battery Status State Diagrams 8.3.3.12.1 Get Battery Status State Diagram Figure 8.156, "Get Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery status for a specified Battery. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.156 Get Battery Status State Diagram 8.3.3.12.1.1 PE_Get_Battery_Status State The Policy Engine Shall transition to the PE_Get_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery status, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Status state the Policy Engine Shall send a Get_Battery_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Status Message is received  Or SenderResponseTimer times out. get Battery status request from Device Policy Manager Battery_Status Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Status Actions on entry: Send Get_Battery_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 871 8.3.3.12.2 Give Battery Status State Diagram Figure 8.157, "Give Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Status Message. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.157 Give Battery Status State Diagram 8.3.3.12.2.1 PE_Give_Battery_Status State The Policy Engine Shall transition to the PE_Give_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Status Message is received. On entry to the PE_Give_Battery_Status state the Policy Engine Shall request the present Battery status, for the requested Battery, from the Device Policy Manager and then send a Battery_Status Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Status Message has been successfully sent. Get_Battery_Status Message received Battery_Status Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Status Actions on entry: Get present Battery status from Device Policy Manager Send Battery_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 872 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.13 Manufacturer Information State Diagrams 8.3.3.13.1 Get Manufacturer Information State Diagram Figure 8.158, "Get Manufacturer Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Manufacturer Information. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.158 Get Manufacturer Information State Diagram 8.3.3.13.1.1 PE_Get_Manufacturer_Info State The Policy Engine Shall transition to the PE_Get_Manufacturer_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Manufacturer_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Manufacturer_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Manufacturer_Info Message is received  Or SenderResponseTimer times out. get manufacturer information request from Device Policy Manager Manufacturer_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Manfacturer_Info Actions on entry: Send Get_Manfacturer_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Manufacturer Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 873 8.3.3.13.2 Give Manufacturer Information State Diagram Figure 8.159, "Give Manufacturer Information State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Manufacturer_Info Message. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.159 Give Manufacturer Information State Diagram 8.3.3.13.2.1 PE_Give_Manufacturer_Info State The Policy Engine Shall transition to the PE_Give_Manufacturer_Info state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Manufacturer_Info Message is received. On entry to the PE_Give_Manufacturer_Info state the Policy Engine Shall request the manufacturer information from the Device Policy Manager and then send a Manufacturer_Info Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Manufacturer_Info Message has been successfully sent. Get_Manufacturer_Info Message received Manufacturer_Info Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Manufacturer_Info Actions on entry: Get present Manufacturer Information from Device Policy Manager Send Manufacturer_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 874 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14 Country Codes and Information State Diagrams 8.3.3.14.1 Get Country Codes State Diagram Figure 8.160, "Get Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Codes. See also Section 6.5.11, "Country_Codes Message". Figure 8.160 Get Country Codes State Diagram 8.3.3.14.1.1 PE_Get_Country_Codes State The Policy Engine Shall transition to the PE_Get_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Country Codes from the Device Policy Manager. On entry to the PE_Get_Country_Codes state the Policy Engine Shall send a Get_Country_Codes Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Codes state the Policy Engine Shall inform the Device Policy Manager of the outcome (Country Codes or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Codes Message is received  Or SenderResponseTimer times out. get country codes request from Device Policy Manager Country_Codes Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Codes Actions on entry: Send Get_Country_Codes Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Codes/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 875 8.3.3.14.2 Give Country Codes State Diagram Figure 8.161, "Give Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Codes Message. See also Section 6.5.11, "Country_Codes Message". Figure 8.161 Give Country Codes State Diagram 8.3.3.14.2.1 PE_Give_Country_Codes State The Policy Engine Shall transition to the PE_Give_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Codes Message is received. On entry to the PE_Give_Country_Codes state the Policy Engine Shall request the country codes from the Device Policy Manager and then send a Country_Codes Message containing these codes. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Codes Message has been successfully sent. Get_Country_Codes Message received Country_Codes Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Codes Actions on entry: Get present Country Codes from Device Policy Manager Send Country_Codes Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 876 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14.3 Get Country Information State Diagram Figure 8.162, "Get Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Information. See also Section 6.5.12, "Country_Info Message". Figure 8.162 Get Country Information State Diagram 8.3.3.14.3.1 PE_Get_Country_Info State The Policy Engine Shall transition to the PE_Get_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Country_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (country information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Info Message is received  Or SenderResponseTimer times out. get country information request from Device Policy Manager Country_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Info Actions on entry: Send Get_Country_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 877 8.3.3.14.4 Give Country Information State Diagram Figure 8.163, "Give Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Info Message. See also Section 6.5.12, "Country_Info Message". Figure 8.163 Give Country Information State Diagram 8.3.3.14.4.1 PE_Give_Country_Info State The Policy Engine Shall transition to the PE_Give_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Info Message is received. On entry to the PE_Give_Country_Info state the Policy Engine Shall request the country information from the Device Policy Manager and then send a Country_Info Message containing this country information. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Info Message has been successfully sent. Get_Country_Info Message received Country_Info Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Info Actions on entry: Get present Country Information from Device Policy Manager Send Country_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 878 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.15 Revision State Diagrams 8.3.3.15.1 Get Revision State Diagram Figure 8.164, "Get Revision State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Revision Information. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.164 Get Revision State Diagram 8.3.3.15.1.1 PE_Get_Revision State The Policy Engine Shall transition to the PE_Get_Revision state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Revision Information from the Device Policy Manager. On entry to the PE_Get_Revision state the Policy Engine Shall send a Get_Revision Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Revision state the Policy Engine Shall inform the Device Policy Manager of the outcome (Revision information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Revision Message is received  Or SenderResponseTimer times out. get Revision request from Device Policy Manager Revision Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Revision Actions on entry: Send Get_Revision Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Revision Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 879 8.3.3.15.2 Give Revision State Diagram Figure 8.165, "Give Revision State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Revision Message. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.165 Give Revision State Diagram 8.3.3.15.2.1 PE_Give_Revision State The Policy Engine Shall transition to the PE_Give_Revision state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Revision Message is received. On entry to the PE_Give_Revision state the Policy Engine Shall request the Revision information from the Device Policy Manager and then send a Revision Message based on this information. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Revision Message has been successfully sent. Get_Revision Message received Revision Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Revision Actions on entry: Get present Revision Information from Device Policy Manager Send Revision Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 880 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.16 Enter_USB Message State Diagrams 8.3.3.16.1 DFP Enter_USB Message State Diagrams Figure 8.166, "DFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message sent by a DFP. Figure 8.166 DFP Enter_USB Message State Diagram 8.3.3.16.1.1 PE_DEU_Send_Enter_USB State The PE_DEU_Send_Enter_USB State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager and the Port is operating as a DFP. On entry to the PE_DEU_Send_Enter_USB State the Policy Engine Shall request the Protocol Layer to send an Enter_USB Message and then initialize and run the SenderResponseTimer. On exit from the PE_DEU_Send_Enter_USB state the Policy Engine Shall inform the Device Policy Manager of the outcome: Accept Message received, Reject Message received, SenderResponseTimer timeout. The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready State depending on the Ports Power Role when:  An Accept Message has been received or  A Wait Message has been received or  A Reject Message has been received  There is a SenderResponseTimer timeout. PE_DEU_Send_Enter_USB Actions on entry: Send Enter_USB Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Enter USB (USB Mode) request from DPM Accept Message Received | Reject Message Received | Wait Message Received | SenderResponseTimer timeout PE_SRC_Ready or PE_SNK_Ready (DFP) Actions on exit: Inform Device Policy Manager of Accept, Wait, Reject or timeout. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 881 8.3.3.16.2 UFP or Cable Plug Enter_USB Message State Diagrams Figure 8.167, "UFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message received by a UFP or Cable Plug. Figure 8.167 UFP Enter_USB Message State Diagram 8.3.3.16.2.1 PE_UEU_Enter_USB_Received State The PE_UEU_Enter_USB_Received state Shall be entered from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when an Enter_USB Message is received and the Port is operating as a UFP or is a Cable Plug. On entry to the PE_UEU_Enter_USB_Received state the Policy Engine Shall inform the Device Policy Manager. The Device Policy Manager responds with an indication of whether the Enter_USB Message is to be accepted or rejected. The Policy Engine Shall send either an Accept Message, a Wait Message or a Reject Message as appropriate. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate when:  Either an Accept Message, a Wait Message or a Reject Message has been sent. PE_SRC_Ready (UFP), PE_SNK_Ready (UFP) or PE_CBL_Ready PE_UEU_Enter_USB_Received Actions on entry: Inform Device Policy Manager of Enter_USB Message Send Accept/Wait/Reject Message based on DPM response Power = Explicit Contract PD = connected Enter_USB Message Received Accept/Wait/Reject Message sent Page 882 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17 Security State Diagrams 8.3.3.17.1 Send Security Request State Diagram Figure 8.168, "Send security request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a security request. See also Section 6.5.8, "Security Messages". Figure 8.168 Send security request State Diagram 8.3.3.17.1.1 PE_Send_Security_Request State The Policy Engine Shall transition to the PE_Send_Security_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a security request from the Device Policy Manager. On entry to the PE_Send_Security_Request state the Policy Engine Shall send a Security_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Security_Request Message has been sent. Send security request from Device Policy Manager Security_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Security_Request Actions on entry: Send Security_Request Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 883 8.3.3.17.2 Send Security Response State Diagram Figure 8.169, "Send security response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Security_Request Message. See also Section 6.5.8, "Security Messages". Figure 8.169 Send security response State Diagram 8.3.3.17.2.1 PE_Send_Security_Response State The Policy Engine Shall transition to the PE_Send_Security_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Security_Request Message is received. On entry to the PE_Send_Security_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Security_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Security_Response Message has been successfully sent. Security_Request Message received Security_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Security_Response Actions on entry: Get present Security response from Device Policy Manager Send Security_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 884 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17.3 Security Response Received State Diagram Figure 8.170, "Security response received State Diagram" shows the state diagram for a Source or Sink on receiving a Security_Response Message. See also Section 6.5.8, "Security Messages". Figure 8.170 Security response received State Diagram 8.3.3.17.3.1 PE_Security_Response_Received State The Policy Engine Shall transition to the PE_Security_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Security_Response Message is received. On entry to the PE_Security_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the security response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Security_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Security_Response_Received Actions on entry: Inform Device Policy Manager of the security response details. Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 885 8.3.3.18 Firmware Update State Diagrams 8.3.3.18.1 Send Firmware Update Request State Diagram Figure 8.171, "Send firmware update request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a firmware update request. See also Section 6.5.9, "Firmware Update Messages". Figure 8.171 Send firmware update request State Diagram 8.3.3.18.1.1 PE_Send_Firmware_Update_Request State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a firmware update request from the Device Policy Manager. On entry to the PE_Send_Firmware_Update_Request state the Policy Engine Shall send a Firmware_Update_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Firmware_Update_Request Message has been sent. Send firmware update request from Device Policy Manager Firmware_Update_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Firmware_Update_Request Actions on entry: Send Firmware_Update_Request Message Power = Explicit Contract PD = Connected Page 886 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.18.2 Send Firmware Update Response State Diagram Figure 8.172, "Send firmware update response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Firmware_Update_Request Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.172 Send firmware update response State Diagram 8.3.3.18.2.1 PE_Send_Firmware_Update_Response State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Firmware_Update_Request Message is received. On entry to the PE_Send_Firmware_Update_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Firmware_Update_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Firmware_Update_Response Message has been successfully sent. Firmware_Update_Request Message received Firmware_Update_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Firmware_Update_Response Actions on entry: Get present firmware update response from Device Policy Manager Send Firmware_Update_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 887 8.3.3.18.3 Firmware Update Response Received State Diagram Figure 8.173, "Firmware update response received State Diagram" shows the state diagram for a Source or Sink on receiving a Firmware_Update_Response Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.173 Firmware update response received State Diagram 8.3.3.18.3.1 PE_Firmware_Update_Response_Received State The Policy Engine Shall transition to the PE_Firmware_Update_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Firmware_Update_Response Message is received. On entry to the PE_Firmware_Update_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the firmware update response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Firmware_Update_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Firmware_Update_Response_Received Actions on entry: Inform Device Policy Manager of the firmware update response details. Power = Explicit Contract PD = Connected Page 888 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19 Dual-Role Port State Diagrams Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition they Shall have the capability to perform a Power Role Swap from the PE_SRC_Ready or PE_SNK_Ready states and Shall return to USB Default Operation on a Hard Reset. The State Diagrams in this section Shall apply to every [USB Type-C 2.4] DRP. 8.3.3.19.1 DFP to UFP Data Role Swap State Diagram Figure 8.174, "DFP to UFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DFP to UFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.174 DFP to UFP Data Role Swap State Diagram 8.3.3.19.1.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Evaluate_Swap state when:  A DR_Swap Message is received and PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DRS_DFP_UFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_DFP_UFP_ Change_to_UFP Actions on entry: Request Device Policy Manager to change port to UFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_DFP_UFP_ Send_Swap Actions on entry: Send Swap DR message Initialize and run SenderResponseTimer Reject message received | Wait message received | SenderResponseTimer timeout PE_DRS_DFP_UFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_DFP_UFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept message sent Port changed to UFP PE_SRC_Ready or PE_SNK_Ready (UFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap message received & in Modal Operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 889  There are no Active Modes (not in Modal Operation). The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.1.2 PE_DRS_DFP_UFP_Evaluate_Swap State On entry to the PE_DRS_DFP_UFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.1.3 PE_DRS_DFP_UFP_Accept_Swap State On entry to the PE_DRS_DFP_UFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  The Accept Message has been sent. 8.3.3.19.1.4 PE_DRS_DFP_UFP_Change_to_UFP State On entry to the PE_DRS_DFP_UFP_Change_to_UFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a DFP to a UFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a UFP. 8.3.3.19.1.5 PE_DRS_DFP_UFP_Send_Swap State On entry to the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  An Accept Message is received. 8.3.3.19.1.6 PE_DRS_DFP_UFP_Reject_Swap State On entry to the PE_DRS_DFP_UFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send: Page 890 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Reject Message if the device is unable to perform a Data Role Swap at this time.  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 891 8.3.3.19.2 UFP to DFP Data Role Swap State Diagram Figure 8.175, "UFP to DFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DRP UFP to DFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.175 UFP to DFP Data Role Swap State Diagram 8.3.3.19.2.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from the either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Evaluate_Swap state when:  A DR_Swap Message is received and  There are no Active Modes (not in Modal Operation). PE_SRC_Ready or PE_SNK_Ready (UFP) PE_DRS_UFP_DFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_UFP_DFP_ Change_to_DFP Actions on entry: Request Device Policy Manager to change port to DFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_UFP_DFP_ Send_Swap Actions on entry: Send Swap DR Message Initialize and run SenderResponseTimer Reject Message received | Wait Message received | SenderResponseTimer timeout PE_DRS_UFP_DFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_UFP_DFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap Message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept Message sent Port changed to DFP PE_SRC_Ready or PE_SNK_Ready (DFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap Message received & in Modal Operation Page 892 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.2.2 PE_DRS_UFP_DFP_Evaluate_Swap State On entry to the PE_DRS_UFP_DFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.2.3 PE_DRS_UFP_DFP_Accept_Swap State On entry to the PE_DRS_UFP_DFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  The Accept Message has been sent. 8.3.3.19.2.4 PE_DRS_UFP_DFP_Change_to_DFP State On entry to the PE_DRS_UFP_DFP_Change_to_DFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a UFP to a DFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a DFP. 8.3.3.19.2.5 PE_DRS_UFP_DFP_Send_Swap State On entry to the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a UFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  An Accept Message is received. 8.3.3.19.2.6 PE_DRS_UFP_DFP_Reject_Swap State On entry to the PE_DRS_UFP_DFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Data Role Swap at this time. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 893  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a UFP and Shall transition to the either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Page 894 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.3 Policy Engine in Source to Sink Power Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.176, "Dual-Role Port in Source to Sink Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Figure 8.176 Dual-Role Port in Source to Sink Power Role Swap State Diagram PE_SRC_Ready PE_PRS_SRC_SNK_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SRC_SNK_ Transition_to_off Actions on entry: Tell Device Policy Manager to turn off power supply Power = Transition to stop sourcing PD = Connected PE_PRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Source off PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SRC_SNK_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected Accept received PE_PRS_SRC_SNK_ Reject_PR_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PS_RDY Message received PE_SNK_Startup PE_PRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Source off PD = Connected Source turned off Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 895 8.3.3.19.3.1 PE_SRC_Ready State The Power Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Evaluate_Swap state when:  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.3.2 PE_PRS_SRC_SNK_Evaluate_Swap State On entry to the PE_PRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK.  Or further evaluation of the Power Role Swap request is needed. 8.3.3.19.3.3 PE_PRS_SRC_SNK_Accept_Swap State On entry to the PE_PRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.3.4 PE_PRS_SRC_SNK_Transition_to_off State On entry to the PE_PRS_SRC_SNK_Transition_to_off state the Policy Engine Shall request the Device Policy Manager to turn off the Source. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that the Source has been turned off. 8.3.3.19.3.5 PE_PRS_SRC_SNK_Assert_Rd State On entry to the PE_PRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.3.6 PE_PRS_SRC_SNK_Wait_Source_on State On entry to the PE_PRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the remote Source is now supplying power. The Policy Engine Shall transition to the ErrorRecovery state when: Page 896 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.3.7 PE_PRS_SRC_SNK_Send_Swap State On entry to the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.3.8 PE_PRS_SRC_SNK_Reject_Swap State On entry to the PE_PRS_SRC_SNK_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SRC_Ready when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 897 8.3.3.19.4 Policy Engine in Sink to Source Power Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.177, "Dual-role Port in Sink to Source Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 898 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.177 Dual-role Port in Sink to Source Power Role Swap State Diagram 8.3.3.19.4.1 PE_SNK_Ready State The Power Role Swap process Shall start only from the PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Evaluate_Swap state when: PE_SNK_Ready PE_PRS_SNK_SRC_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Tell Device Policy Manager to turn off Power Sink. Power = Transition to stop sinking PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SNK_SRC_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SNK_SRC_Accept_Swap Actions on entry: Send Accept Message Disable Fast Role Swap Receiver if enabled Power = Explicit Contract PD = Connected Accept Message received PE_PRS_SNK_SRC_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PE_PRS_SNK_SRC_ Source_on Actions on entry: Tell Device Policy Manager to turn on Source Power = Transition to source on PD = Connected VBUS is at vSafe5V Actions on exit: Send PS_RDY Message PE_SRC_Startup Message sent PE_PRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Source off PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 899  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.4.2 PE_PRS_SNK_SRC_Evaluate_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK. 8.3.3.19.4.3 PE_PRS_SNK_SRC_Accept_Swap State On entry to the PE_PRS_SNK_SRC_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message and Shall disable the Fast Role Swap receiver if this is enabled. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.4.4 PE_PRS_SNK_SRC_Transition_to_off State On entry to the PE_PRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Assert_Rp state when:  A PS_RDY Message is received. 8.3.3.19.4.5 PE_PRS_SNK_SRC_Assert_Rp State On entry to the PE_PRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.4.6 PE_PRS_SNK_SRC_Source_on State On entry to the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Source Port VBUS is at vSafe5V. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Page 900 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.4.7 PE_PRS_SNK_SRC_Send_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.4.8 PE_PRS_SNK_SRC_Reject_Swap State On entry to the PE_PRS_SNK_SRC_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 901 8.3.3.19.5 Policy Engine in Source to Sink Fast Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.178, "Dual-Role Port in Source to Sink Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Page 902 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.178 Dual-Role Port in Source to Sink Fast Role Swap State Diagram PE_SRC_Ready PE_FRS_SRC_SNK_ Evaluate_Swap Actions on entry: Ask Device Policy Manager if Fast Role Swap signaled on CC wire Power = Implicit Contract PD = Connected PE_FRS_SRC_SNK_ Transition_to_off Actions on entry: Wait for VBUS to reach vSafe5V Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Implicit Contract PD = Connected Fast Role Swap signaled Accept Message sent PS_RDY Message received PE_SNK_Startup PE_FRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Implicit contract PD = Connected VBUS at vSafe5V Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Accept Message not sent after retries (no GoodCRC received) PE_SRC_Hard_Reset FR_Swap Message received Fast Role Swap not signaled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 903 8.3.3.19.5.1 PE_SRC_Ready State The Fast Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Evaluate_Swap state when:  An FR_Swap Message is received. 8.3.3.19.5.2 PE_FRS_SRC_SNK_Evaluate_Swap State On entry to the PE_FRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether Fast Role Swap has been signaled on the CC wire. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Fast Role Swap has been signaled. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Device Policy Manager indicates that a Fast Role Swap is not being signaled. 8.3.3.19.5.3 PE_FRS_SRC_SNK_Accept_Swap State On entry to the PE_FRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Accept Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.5.4 PE_FRS_SRC_SNK_Transition_to_off State On entry to the PE_FRS_SRC_SNK_Transition_to_off state the Policy Engine Shall wait until VBUS has discharged to vSafe5V. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that VBUS has discharged to vSafe5V. 8.3.3.19.5.5 PE_FRS_SRC_SNK_Assert_Rd State On entry to the PE_FRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.5.6 PE_FRS_SRC_SNK_Wait_Source_on State On entry to the PE_FRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the New Source is now applying Rp. The Policy Engine Shall transition to the ErrorRecovery state when: Page 904 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 905 8.3.3.19.6 Policy Engine in Sink to Source Fast Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.179, "Dual-role Port in Sink to Source Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 906 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.179 Dual-role Port in Sink to Source Fast Role Swap State Diagram PE_FRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Power = Implicit Contract PD = Connected Fast Swap signal detected on CC Wire PE_FRS_SNK_SRC_ Send_Swap Actions on entry: Send FR_Swap Message Initialize and run SenderResponseTimer Power = Implicit Contract PD = Connected Accept Message received PE_FRS_SNK_SRC_ Source_on Actions on entry: Send PS_RDY Message Power = Transition to source on PD = Connected PS_RDY Message sent PE_SRC_Startup PE_FRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Implicit Contract PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout SenderResponseTimer timeout | FR_Swap Message not sent after retries (no GoodCRC received) PE_FRS_SNK_SRC_Vbus_Applied Actions on entry: Request Device Policy Manager to notify when vSafe5v is being applied by the local power source. Power = Implicit Contract PD = Connected New Source is applying vSafe5V PE_FRS_SNK_SRC_ Start_AMS Actions on entry: Notify the Protocol Layer that the first Message in the AMS will follow. Power = Implicit Contract PD = Connected Protocol Layer notified Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 907 8.3.3.19.6.1 PE_FRS_SNK_SRC_Start_AMS State The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Start_AMS state from any other state provided there is an Explicit Contract in place when:  The Sink Capabilities received from the Initial Source by the Policy Engine has at least one of the Fast Role Swap bits set.  The system has sufficient reserve power to provide the requested current to the Initial Source, as requested in the Fast Role Swap bits in the Sink Capabilities, and is willing to dedicate it to the Port  The Device Policy Manager indicates that a Fast Role Swap signal has been detected on the CC wire. On entry to the PE_FRS_SNK_SRC_Start_AMS state the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Send_Swap state when:  The Protocol Layer has been notified. 8.3.3.19.6.2 PE_FRS_SNK_SRC_Send_Swap State On entry to the PE_FRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send an FR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. The Policy Engine Shall transition to the ErrorRecovery state when:  The SenderResponseTimer times out or  The FR_Swap Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. 8.3.3.19.6.3 PE_FRS_SNK_SRC_Transition_to_off State On entry to the PE_FRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_VBUS_Applied state when:  A PS_RDY Message is received. 8.3.3.19.6.4 PE_FRS_SNK_SRC_VBUS_Applied State On entry to the PE_FRS_SNK_SRC_VBUS_Applied state the Policy Engine waits for a notification from the Device Policy Manager that the local power source has applied vSafe5V to VBUS (see Section 5.8.6.3, "Fast Role Swap Detection"). Note: This could have already been applied prior to entering this state or could be applied while waiting in this state. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Assert_Rp state when:  The Device Policy Manager indicates that vSafe5V is being applied. 8.3.3.19.6.5 PE_FRS_SNK_SRC_Assert_Rp State On entry to the PE_FRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. Page 908 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rp is asserted. 8.3.3.19.6.6 PE_FRS_SNK_SRC_Source_on State On entry to the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 909 8.3.3.19.7 Dual-Role (Source Port) Get Source Capabilities State Diagram Figure 8.180, "Dual-Role (Source) Get Source Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.180 Dual-Role (Source) Get Source Capabilities diagram 8.3.3.19.7.1 PE_DR_SRC_Get_Source_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap state, from the PE_SRC_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready State (see Figure 8.132, "Source Port State Diagram") when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. get source capabilities request from Device Policy Manager SPR Souce Capabilities requested & Source_Capabilities Message received | EPR Souce Capabilities requested & EPR_Source_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap Actions on entry: If SPR Source Capabilities requested Send Get_Source_Cap Message1 If EPR Source Capabilities requested Send EPR_Get_Source_Cap Message1 Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source capabilities/outcome to Device Policy Manager 1) Either SPR or EPR Source Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. Page 910 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.8 Dual-Role (Source Port) Give Sink Capabilities State Diagram Figure 8.181, "Dual-Role (Source) Give Sink Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a Get_Sink_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.181 Dual-Role (Source) Give Sink Capabilities diagram 8.3.3.19.8.1 PE_DR_SRC_Give_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap state, from the PE_SRC_Ready state, when a Get_Sink_Cap Message or EPR_Get_Sink_Cap Message is received.  On entry to the PE_DR_SRC_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Sink_Capabilities Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap_Ext Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 911 8.3.3.19.9 Dual-Role (Sink Port) Get Sink Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's Sink Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.182 Dual-Role (Sink) Get Sink Capabilities State Diagram 8.3.3.19.9.1 PE_DR_SNK_Get_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap state, from the PE_SNK_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SNK_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). If Fast Role Swap is supported, request Device Policy Manager prepare or disable 5V source and configure the Fast Role Swap receiver based on the Fast Role Swap required USB Type- C Current bits in the received Sink Capabilities. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager1 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Request Device Policy Manager to configure Fast Role Swap if supported 1) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Sink is currently operating in SPR or EPR Mode. Page 912 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.10 Dual-Role (Sink Port) Give Source Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.183 Dual-Role (Sink) Give Source Capabilities State Diagram 8.3.3.19.10.1 PE_DR_SNK_Give_Source_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap state, from the PE_SNK_Ready state, when a Get_Source_Cap Message is received.  On entry to the PE_DR_SNK_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities.  The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source Capabilities Message has been successfully sent. (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities Message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 913 8.3.3.19.11 Dual-Role (Source Port) Get Source Capabilities Extended State Diagram Figure 8.184, "Dual-Role (Source) Get Source Capabilities Extended State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.184 Dual-Role (Source) Get Source Capabilities Extended State Diagram 8.3.3.19.11.1 PE_DR_SRC_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Page 914 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.12 Dual-Role (Sink Port) Give Source Capabilities Extended State Diagram Figure 8.185, "Dual-Role (Sink) Give Source Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.185 Dual-Role (Sink) Give Source Capabilities Extended diagram 8.3.3.19.12.1 PE_DR_SNK_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_DR_SNK_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 915 8.3.3.19.13 Dual-Role (Sink Port) Get Sink Capabilities Extended State Dia- gram Figure 8.186, "Dual-Role (Sink) Get Sink Capabilities Extended State Diagram" shows the state diagram for a Dual- Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.186 Dual-Role (Sink) Get Sink Capabilities Extended State Diagram 8.3.3.19.13.1 PE_DR_SNK_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Sink_Capabilities_Extended Message is received.  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Sink extended capabilities/outcome to Device Policy Manager Page 916 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.14 Dual-Role (Source Port) Give Sink Capabilities Extended State Diagram Figure 8.187, "Dual-Role (Source) Give Sink Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.187 Dual-Role (Source) Give Sink Capabilities Extended diagram 8.3.3.19.14.1 PE_DR_SRC_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_DR_SRC_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Sink Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram")when:  The Sink_Capabilities_Extended Message has been successfully sent. _Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink Capabilities Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 917 8.3.3.19.15 Dual-Role (Source Port) Get Source Information State Diagram Figure 8.188, "Dual-Role (Source) Get Source Information State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.188 Dual-Role (Source) Get Source Information State Diagram 8.3.3.19.15.1 PE_DR_SRC_Get_Source_Info State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Info state, from the PE_SRC_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Info Message is received.  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Page 918 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.16 Dual-Role (Sink Port) Give Source Information State Diagram Figure 8.189, "Dual-Role (Source) Give Source Information diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.189 Dual-Role (Source) Give Source Information diagram 8.3.3.19.16.1 PE_DR_SNK_Give_Source_Info State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Info state, from the PE_SNK_Ready state, when a Get_Source_Info Message is received. On entry to the PE_DR_SNK_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 919 8.3.3.20 VCONN Swap State Diagram The State Diagram in this section Shall apply to Ports that supply VCONN. Figure 8.190, "VCONN Swap State Diagram" shows the state operation for a Port on sending or receiving a VCONN Swap request. Figure 8.190 VCONN Swap State Diagram 8.3.3.20.1 PE_VCS_Send_Swap State The PE_VCS_Send_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a request from the Device Policy Manager to perform a VCONN Swap. On entry to the PE_VCS_Send_Swap state the Policy Engine Shall send a VCONN_Swap Message and start the SenderResponseTimer. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  An Accept Message is received and  The Port is presently the VCONN Source. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  An Accept Message is received and  The Port is not presently the VCONN Source. PE_VCS_Evaluate_Swap Actions on entry: Get evaluation of VCONN swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_VCS_Turn_On_VCONN Actions on entry: Tell Device Policy Manager to turn on VCONN PE_VCS_Send_PS_Rdy Actions on entry: Send PS_RDY Message PE_VCS_Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected PE_VCS_Reject_VCONN_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent VCONN_Swap Message received VCONN Swap ok (Not Presently VCONN SOURCE & VCONN Swap not ok) | Further evaluation Required Accept Message sent & Not presently VCONN Source1 VCONN turned on PS_RDY Message sent VCONNOnTimer Timeout Hard Reset: Consumer/Provider -> PE_SNK_Hard_Reset Provider/Consumer -> PE_SRC_Hard_Reset Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_VCS_Wait_for_VCONN Actions on entry: Start VCONNOnTimer Power = Explicit Contract PD = Connected Accept Message sent & Presently VCONN Source1 PE_VCS_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = Connected PS_RDY Message received Device Policy Manager Informed VCONN Swap required (indication from Device Policy Manager) PE_VCS_Send_Swap Actions on entry: Send VCONN_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout Accept Message received & Presently VCONN Source1 Accept Message received & Not presently VCONN Source1 PE_VCS_Force_VCONN2 Actions on entry: Tell Device Policy Manager to turn on VCONN Power = Explicit Contract PD = Connected Not_Supported Message received & Not presently VCONN Source1 VCONN turned on PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Entry_ACK PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_SNK_EPR_Mode_Entry_Wait_For_Response PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable 1) A Port is presently the VCONN Source if it has the responsibility for supplying VCONN even if VCONN has been turned off. 2) The PE_VCS_Force_VCONN state is Optional. Page 920 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  A Reject Message is received or  A Wait Message is received or  The SenderResponseTimer times out. The Policy Engine May transition to the PE_VCS_Force_VCONN state when:  A Not_Supported Message is received and  The Port is not presently the VCONN Source. 8.3.3.20.2 PE_VCS_Evaluate_Swap State The PE_VCS_Evaluate_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a VCONN_Swap Message. On entry to the PE_VCS_Evaluate_Swap state the Policy Engine Shall request the Device Policy Manager for an evaluation of the VCONN Swap request. The Policy Engine Shall transition to the PE_VCS_Accept_Swap state when:  The Device Policy Manager indicates that a VCONN Swap is OK. The Policy Engine Shall transition to the PE_VCS_Reject_Swap state when:  The Port is not presently the VCONN Source and the Device Policy Manager indicates that a VCONN Swap is not OK or  The Device Policy Manager indicates that a VCONN Swap cannot be done at this time. 8.3.3.20.3 PE_VCS_Accept_Swap State On entry to the PE_VCS_Accept_Swap state the Policy Engine Shall send an Accept Message. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is on. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is off. 8.3.3.20.4 PE_VCS_Reject_Swap State On entry to the PE_VCS_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a VCONN Swap at this time.  A Wait Message if further evaluation of the VCONN Swap request is required. Note: In this case it is expected that the Port will send a VCONN_Swap Message at a later time. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 921 8.3.3.20.5 PE_VCS_Wait_for_VCONN State On entry to the PE_VCS_Wait_For_VCONN state the Policy Engine Shall start the VCONNOnTimer. The Policy Engine Shall transition to the PE_VCS_Turn_Off_VCONN state when:  A PS_RDY Message is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state when:  The VCONNOnTimer times out. 8.3.3.20.6 PE_VCS_Turn_Off_VCONN State On entry to the PE_VCS_Turn_Off_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Device Policy Manager has been informed. 8.3.3.20.7 PE_VCS_Turn_On_VCONN State On entry to the PE_VCS_Turn_On_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition to the PE_VCS_Send_Ps_Rdy state when:  The Port's VCONN is on. 8.3.3.20.8 PE_VCS_Send_PS_Rdy State On entry to the PE_VCS_Send_Ps_Rdy state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The PS_RDY Message has been sent. 8.3.3.20.9 PE_VCS_Force_VCONN State On entry to the PE_VCS_Force_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Port's VCONN is on. 8.3.3.21 Initiator Structured VDM State Diagrams The State Diagrams in this section Shall apply to all Initiators. Page 922 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.1 Initiator Structured VDM Discover Identity State Diagram Figure 8.191, "Initiator to Port VDM Discover Identity State Diagram" shows the state diagram for an Initiator when discovering the identity of its Port Partner or Cable Plug. Figure 8.191 Initiator to Port VDM Discover Identity State Diagram 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_Request State The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the identity of the Port Partner or Cable Plug or  The DiscoverIdentityTimer times out. The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from the PE_SRC_EPR_Mode_Discover_Cable state when:  The Cable Plug Discovery Process has been initiated. PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_INIT_PORT_VDM_Identity_Request Actions on entry: Send Discover Identity request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests identity discovery1 | DiscoverIdentityTimer timeout Discover Identity ACK received PE_INIT_PORT_VDM_Identity_ACKed Actions on entry: Inform DPM of identity Power = Explicit Contract PD = Connected PE_INIT_PORT_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR 1) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 923 On entry to the PE_INIT_PORT_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out. 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_ACKed State On entry to the PE_INIT_PORT_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. 8.3.3.21.1.3 PE_INIT_PORT_VDM_Identity_NAKed State On entry to the PE_INIT_PORT_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. Page 924 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.2 Initiator Structured VDM Discover SVIDs State Diagram Figure 8.192, "Initiator VDM Discover SVIDs State Diagram" shows the state diagram for an Initiator when discovering SVIDs of its Port Partner or Cable Plug. Figure 8.192 Initiator VDM Discover SVIDs State Diagram 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_Request State The Policy Engine transitions to the PE_INIT_VDM_SVIDs_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the SVIDs of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_SVIDs_Request state the Policy Engine Shall send a Structured VDM Discover SVIDs Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_ACKed state when:  A Structured VDM Discover SVIDs ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_NAKed state when:  A Structured VDM Discover SVIDs NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_SVIDs_Request Actions on entry: Send Discover SVIDs request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests SVIDs discovery Discover SVIDs ACK received PE_INIT_VDM_SVIDs_ACKed Actions on entry: Inform DPM of SVIDs Power = Explicit Contract PD = Connected PE_INIT_VDM_SVIDs_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover SVIDs NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 925 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_ACKed State On entry to the PE_INIT_VDM_SVIDs_ACKed state the Policy Engine Shall inform the Device Policy Manager of the SVIDs information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. 8.3.3.21.2.3 PE_INIT_VDM_SVIDs_NAKed State On entry to the PE_INIT_VDM_SVIDs_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. Page 926 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.3 Initiator Structured VDM Discover Modes State Diagram Figure 8.193, "Initiator VDM Discover Modes State Diagram" shows the state diagram for an Initiator when discovering Modes of its Port Partner or Cable Plug. Figure 8.193 Initiator VDM Discover Modes State Diagram 8.3.3.21.3.1 PE_INIT_VDM_Modes_Request State The Policy Engine transitions to the PE_INIT_VDM_Modes_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the Modes of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_Modes_Request state the Policy Engine Shall send a Structured VDM Discover Modes Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_ACKed state when:  A Structured VDM Discover Modes ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_NAKed state when:  A Structured VDM Discover Modes NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Modes_Request Actions on entry: Send Discover Modes request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests Modes discovery Discover Modes ACK received PE_INIT_VDM_Modes_ACKed Actions on entry: Inform DPM of Modes Power = Explicit Contract PD = Connected PE_INIT_VDM_Modes_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Modes NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 927 8.3.3.21.3.2 PE_INIT_VDM_Modes_ACKed State On entry to the PE_INIT_VDM_Modes_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Modes information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. 8.3.3.21.3.3 PE_INIT_VDM_Modes_NAKed State On entry to the PE_INIT_VDM_Modes_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Page 928 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.4 Initiator Structured VDM Attention State Diagram Figure 8.194, "Initiator VDM Attention State Diagram" shows the state diagram for an Initiator when sending an Attention Command request. Figure 8.194 Initiator VDM Attention State Diagram 8.3.3.21.4.1 PE_INIT_VDM_Attention_Request State The Policy Engine transitions to the PE_INIT_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  When the Device Policy Manager requests attention from its Port Partner. On entry to the PE_INIT_VDM_Attention_Request state the Policy Engine Shall send an Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Attention Command request has been sent. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Attention_Request Actions on entry: Send Attention Command request Power = Explicit Contract PD = Connected Attention request from DPM Attention Command request sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 929 8.3.3.22 Responder Structured VDM State Diagrams 8.3.3.22.1 Responder Structured VDM Discover Identity State Diagram Figure 8.195, "Responder Structured VDM Discover Identity State Diagram" shows the state diagram for a Responder receiving a Discover Identity Command request. Figure 8.195 Responder Structured VDM Discover Identity State Diagram 8.3.3.22.1.1 PE_RESP_VDM_Get_Identity State The Policy Engine transitions to the PE_RESP_VDM_Get_Identity state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Identity Command request is received. On entry to the PE_RESP_VDM_Get_Identity state the Responder Shall request identity information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Identity state when:  Identity information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Identity_NAK state when:  The Device Policy Manager indicates that the response to the Discover Identity Command request is NAK or BUSY. 8.3.3.22.1.2 PE_RESP_VDM_Send_Identity State On entry to the PE_RESP_VDM_Send_Identity state the Responder Shall send the Structured VDM Discover Identity ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Discover Identity ACK Command response has been sent. 8.3.3.22.1.3 PE_RESP_VDM_Get_Identity_NAK State On entry to the PE_RESP_VDM_Get_Identity_NAK state the Policy Engine Shall send a Structured VDM Discover Identity NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Identity NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Identity Actions on entry: Send Discover Identity ACK Power = Explicit Contract PD = Connected Discover Identity request Discover Identity ACK sent PE_RESP_VDM_Get_Identity Actions on entry: Request Identity information from DPM Power = Explicit Contract PD = Connected Identity information from DPM PE_RESP_VDM_Get_Identity_NAK Actions on entry: Send Discover Identity NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Identity NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 930 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.2 Responder Structured VDM Discover SVIDs State Diagram Figure 8.196, "Responder Structured VDM Discover SVIDs State Diagram" shows the state diagram for a Responder when receiving a Discover SVIDs Command. Figure 8.196 Responder Structured VDM Discover SVIDs State Diagram 8.3.3.22.2.1 PE_RESP_VDM_Get_SVIDs State The Policy Engine transitions to the PE_RESP_VDM_Get_SVIDs state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover SVIDs Command request is received. On entry to the PE_RESP_VDM_Get_SVIDs state the Responder Shall request SVIDs information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_SVIDs state when:  SVIDs information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_SVIDs_NAK state when:  The Device Policy Manager indicates that the response to the Discover SVIDs Command request is NAK or BUSY. 8.3.3.22.2.2 PE_UFP_VDM_Send_SVIDs State On entry to the PE_RESP_VDM_Send_SVIDs state the Responder Shall send the Structured VDM Discover SVIDs ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs ACK Command response has been sent. 8.3.3.22.2.3 PE_UFP_VDM_Get_SVIDs_NAK State On entry to the PE_RESP_VDM_Get_SVIDs_NAK state the Policy Engine Shall send a Structured VDM Discover SVIDs NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_SVIDs Actions on entry: Send Discover SVIDs ACK Power = Explicit Contract PD = Connected Discover SVIDs request Discover SVIDs ACK sent PE_RESP_VDM_Get_SVIDs Actions on entry: Request SVIDs information from DPM Power = Explicit Contract PD = Connected SVIDs information from DPM PE_RESP_VDM_Get_SVIDs_NAK Actions on entry: Send Discover SVIDs NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover SVIDs NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 931 8.3.3.22.3 Responder Structured VDM Discover Modes State Diagram Figure 8.197, "Responder Structured VDM Discover Modes State Diagram" shows the state diagram for a Responder on receiving a Discover Modes Command. Figure 8.197 Responder Structured VDM Discover Modes State Diagram 8.3.3.22.3.1 PE_RESP_VDM_Get_Modes State The Policy Engine transitions to the PE_RESP_VDM_Get_Modes state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Modes Command request is received. On entry to the PE_RESP_VDM_Get_Modes state the Responder Shall request Modes information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Modes state when:  Modes information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Modes_NAK state when:  The Device Policy Manager indicates that the response to the Discover Modes Command request is NAK or BUSY. 8.3.3.22.3.2 PE_RESP_VDM_Send_Modes State On entry to the PE_RESP_VDM_Send_Modes state the Responder Shall send the Structured VDM Discover Modes ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes ACK Command response has been sent. 8.3.3.22.3.3 PE_RESP_VDM_Get_Modes_NAK State On entry to the PE_RESP_VDM_Get_Modes_NAK state the Policy Engine Shall send a Structured VDM Discover Modes NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Modes Actions on entry: Send Discover Modes ACK Power = Explicit Contract PD = Connected Discover Modes request Discover Modes ACK sent PE_RESP_VDM_Get_Modes Actions on entry: Request Modes information from DPM Power = Explicit Contract PD = Connected Modes information from DPM PE_RESP_VDM_Get_Modes_ NAK Actions on entry: Send Discover Modes NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Modes NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 932 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.4 Receiving a Structured VDM Attention State Diagram Figure 8.198, "Receiving a Structured VDM Attention State Diagram" shows the state diagram when receiving an Attention Command request. Figure 8.198 Receiving a Structured VDM Attention State Diagram 8.3.3.22.4.1 PE_RCV_VDM_Attention_Request State The Policy Engine transitions to the PE_RCV_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  An Attention Command request is received. On entry to the PE_RCV_VDM_Attention_Request state the Policy Engine Shall inform the Device Policy Manager of the Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. PE_SRC_Ready or PE_SNK_Ready PE_RCV_VDM_Attention_Request Actions on entry: Inform Device Policy Manager of Attention Command request Power = Explicit Contract PD = Connected Attention Command request received DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 933 8.3.3.23 DFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all DFPs that support Structured VDMs. 8.3.3.23.1 DFP Structured VDM Mode Entry State Diagram Figure 8.199, "DFP VDM Mode Entry State Diagram" shows the state operation for a DFP when entering a Mode. Figure 8.199 DFP VDM Mode Entry State Diagram 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Entry_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug enter a Mode. On entry to the PE_DFP_VDM_Mode_Entry_Request state the Policy Engine Shall send a Structured VDM Enter Mode Command request and Shall start the VDMModeEntryTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Enter Mode ACK Command response is received. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_NAKed state when:  A Structured VDM Enter Mode NAK or BUSY Command response is received or  The VDMModeEntryTimer times out. PE_SRC_Ready or PE_SNK_Ready (DFP) DPM requests Mode entry1 PE_DFP_VDM_Mode_Entry_ACKed Actions on entry: Request DPM to enter the mode Power = Explicit Contract PD = Connected PE_DFP_VDM_Mode_Entry_Request Actions on entry: Send Mode Entry request Start VDMModeEntryTimer Power = Explicit Contract PD = Connected Mode Entry ACK received Mode entered PE_DFP_VDM_Mode_Entry_NAKed Actions on entry: Inform DPM of reason for failure Power = Explicit Contract PD = Connected Mode Entry NAK/BUSY Received | VDMModeEntryTimer timeout | Protocol Error3 DPM informed2 1) The Device Policy Manager Shall have placed the system into USB Safe State before issuing this request when entering Modal operation. 2) The Device Policy Manager Shall have returned the system to USB operation if not in Modal operation at this point. 3) Protocol Errors are handled by informing the DPM, returning to USB Safe State and then processing the Message once the PE_SRC_Ready or PE_SNK_Ready state has been entered. Page 934 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_ACKed State On entry to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall request the Device Policy Manager to enter the Mode. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Mode has been entered. 8.3.3.23.1.3 PE_DFP_VDM_Mode_Entry_NAKed State On entry to the PE_DFP_VDM_Mode_Entry_NAKed state the Policy Engine Shall inform the Device Policy Manager of the reason for failure (NAK, BUSY, timeout or Protocol Error). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 935 8.3.3.23.2 DFP Structured VDM Mode Exit State Diagram Figure 8.200, "DFP VDM Mode Exit State Diagram" shows the state diagram for a DFP when exiting a Mode. Figure 8.200 DFP VDM Mode Exit State Diagram 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Exit_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug exit a Mode. On entry to the PE_DFP_VDM_Mode_Exit_Request state the Policy Engine Shall send a Structured VDM Exit Mode Command request and Shall start the VDMModeExitTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Exit Mode ACK or NAK Command response is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state depending on the present Power Role when:  A Structured VDM Exit Mode BUSY Command response is received or  The VDMModeExitTimer times out. 8.3.3.23.2.2 PE_DFP_VDM_DFP_Mode_Exit_ACKed State On Exit to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall inform the Device Policy Manager Of the result: ACK or NAK. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when: PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DFP_VDM_Mode_Exit_Request Actions on entry: Send Exit Mode request Start VDMModeExitTimer Power = Explicit Contract PD = Connected DPM indicates Mode exit PE_DFP_VDM_Exit_Mode_ACKed Actions on entry: Inform DPM of ACK or NAK Power = Explicit Contract PD = Connected Exit Mode ACK/NAK received DPM informed1 PE_SRC_Hard_Reset or PE_SNK_Hard_Reset (DFP) Exit Mode BUSY Received | VDMModeExitTimer Timeout 1) The Device Policy Manager is required to return the system to USB operation at this point when exiting Modal Operation. Page 936 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 937 8.3.3.24 UFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all UFPs that support Structured VDMs. 8.3.3.24.1 UFP Structured VDM Enter Mode State Diagram Figure 8.201, "UFP Structured VDM Enter Mode State Diagram" shows the state diagram for a UFP in response to an Enter Mode Command. Figure 8.201 UFP Structured VDM Enter Mode State Diagram 8.3.3.24.1.1 PE_UFP_VDM_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_UFP_VDM_Evaluate_Mode_Entry state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_UFP_VDM_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected Enter Modes request1 PE_UFP_VDM_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_UFP_VDM_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_UFP_VDM_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 938 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_ACK State On entry to the PE_UFP_VDM_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.24.1.3 PE_UFP_VDM_Mode_Entry_NAK State On entry to the PE_UFP_VDM_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 939 8.3.3.24.2 UFP Structured VDM Exit Mode State Diagram Figure 8.202, "UFP Structured VDM Exit Mode State Diagram" shows the state diagram for a UFP in response to an Exit Mode Command. Figure 8.202 UFP Structured VDM Exit Mode State Diagram 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit State The Policy Engine transitions to the PE_UFP_VDM_Mode_Exit state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_UFP_VDM_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. PE_UFP_VDM_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Power = Explicit Contract PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_UFP_VDM_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Power = Explicit Contract PD = Connected Mode exited PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected PE_UFP_VDM_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Power = Explicit Contract PD = Connected DPM says NAK Exit Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 940 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_ACK State On entry to the PE_UFP_VDM_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.24.2.3 PE_UFP_VDM_Mode_Exit_NAK State On entry to the PE_UFP_VDM_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 941 8.3.3.25 Cable Plug Specific State Diagrams The State Diagrams in this section Shall apply to all Cable Plugs that support Structured VDMs. 8.3.3.25.1 Cable Plug Cable Ready State Diagram Figure 8.203, "Cable Ready State Diagram" shows the Cable Ready state diagram for a Cable Plug. Figure 8.203 Cable Ready State Diagram 8.3.3.25.1.1 PE_CBL_Ready State The PE_CBL_Ready state shown in the following sections is the normal operational state for a Cable Plug and where it starts after power up or a Hard/Cable Reset. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Power up | Hard Reset Complete | Cable Reset Complete Page 942 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2 Soft/Hard/Cable Reset 8.3.3.25.2.1 Cable Plug Soft Reset State Diagram Figure 8.204, "Cable Plug Soft Reset State Diagram" shows the Cable Plug state diagram on reception of a Soft_Reset Message. Figure 8.204 Cable Plug Soft Reset State Diagram 8.3.3.25.2.1.1 PE_CBL_Soft_Reset State The PE_CBL_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received from the Protocol Layer. On entry to the PE_CBL_Soft_Reset state the Policy Engine Shall reset the Protocol Layer in the Cable Plug and Shall then request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Accept Message has been sent or  The Protocol Layer indicates that a transmission error has occurred. Accept Message sent | Transmission Error indication from Protocol Layer Soft Reset Message received PE_CBL_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept Message Cable = Awake PD = Connected PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 943 8.3.3.25.2.2 Cable Plug Hard Reset State Diagram Figure 8.205, "Cable Plug Hard Reset State Diagram" shows the Cable Plug state diagram for a Hard Reset or Cable Reset. Figure 8.205 Cable Plug Hard Reset State Diagram 8.3.3.25.2.2.1 PE_CBL_Hard_Reset State The PE_CBL_Hard_Reset state Shall be entered from any state when either Hard Reset Signaling or Cable Reset Signaling is detected. On entry to the PE_CBL_Hard_Reset state the Policy Engine Shall reset the Cable Plug (equivalent to a power cycle). The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Cable Plug reset is complete. Hard Reset signalling Received | Cable Reset Command PE_CBL_Hard_Reset Actions on entry: Reset Cable Plug Cable = Awake/Asleep PD = Not Connected Cable reset complete PE_CBL_Ready Page 944 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.3 DFP/VCONN Source SOP'/SOP'' Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram Figure 8.206, "DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the Policy Engine in a VCONN Source when performing a Soft Reset or Cable Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.206 DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Soft_Reset State The PE_DFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_DFP_VCS_CBL_Send_Soft_Reset state the DFP Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug/VPD, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the DFP VCONN Source's Power Role, when:  There is no Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Send_Capabilities state or PE_SRC_Discovery state, depending on the DFP's VCONN Source's Power Role, when:  There is an Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to the PE_DFP_VCS_CBL_Send_Cable_Reset state when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_DFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered| Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error In Explicit Contract & Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_DFP_VCS_CBL_Send_Cable_Reset Actions on entry: Send Cable Reset Message Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Cable Reset Request from Device Policy Manager Cable Reset sent PE_SRC_Send_Capabilities or PE_SRC_Discovery2 (VCONN Source) Not in Explicit Contract & Accept Message Received on SOP’/SOP’’ 1) Excludes the Soft_Reset Message itself. 2) Sink only communicates with the Cable Plug when in an Explicit Contract. If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 945 8.3.3.25.2.3.2 PE_DFP_VCS_CBL_Send_Cable_Reset State The PE_DFP_VCS_CBL_Send_Cable_Reset state Shall be entered from any state when the Device Policy Manager requests a Cable Reset. On entry to the PE_DFP_VCS_CBL_Send_Cable_Reset state the DFP Policy Engine Shall request the Protocol Layer to send Cable Reset Signaling. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the VCONN Source's Power Role, when:  Cable Reset Signaling has been sent. Page 946 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.4 UFP/VCONN Source SOP'/SOP'' Soft Reset of a Cable Plug or VPD State Diagram Figure 8.207, "UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the UFP Policy Engine in a VCONN Source when performing a Soft Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.207 UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.4.1 PE_UFP_VCS_CBL_Send_Soft_Reset State The PE_UFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_UFP_VCS_CBL_Send_Soft_Reset state the Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the UFP VCONN Source's Power Role, when:  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state, depending on the UFP VCONN Source's Power Role, when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_UFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered | Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_SRC_Hard_Reset or PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 947 8.3.3.25.3 Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" shows the state diagram for Source discovery of identity information from a Cable Plug during the startup sequence. Figure 8.208 Source Startup Structured VDM Discover Identity State Diagram 8.3.3.25.3.1 PE_SRC_VDM_Identity_Request State The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Startup state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Discovery state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug and  The DiscoverIdentityCounter < nDiscoverIdentityCount. Even though there has been a transition out of the PE_SRC_Discovery state the SourceCapabilityTimer Shall continue to run during the states shown in Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" and Shall Not be initialized on re-entry to PE_SRC_Discovery. PE_SRC_Send_Capabilities or PE_SRC_Discovery1 PE_SRC_VDM_Identity_Request Actions on entry: Send Discover Identity request Increment the DiscoverIdentityCounter Start VDMResponseTimer Power = No or Implicit Contract Cable Plug = Not PD Connected DPM requests identity discovery3 & Protocol Layer Reset Complete Discover Identity ACK received PE_SRC_VDM_Identity_ACKed Actions on entry: Inform DPM of identity PE_SRC_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power =No or Implicit Contract Cable Plug = PD Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout | Discover Identity request sending failure (without GoodCRC) DPM informed DPM informed PE_SRC_Startup DPM requests identity discovery & DiscoverIdentityCounter < nDiscoverIdentityCount2 PE_SRC_Discovery Power = No or Implicit Contract Cable Plug = PD Connected 1) If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. 2) The SourceCapabilityTimer continues to run during the states defined in this diagram even though there has been an exit from the PE_SRC_Discovery state. This ensures that Source_Capabilities Messages are sent out at a regular rate. 3) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Page 948 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: An EPR Source is required to discover the identity of the Cable Plug prior to entering the First Explicit Contract (see Section 6.4.10.1, "Process to enter EPR Mode") On entry to the PE_SRC_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request, Shall increment the DiscoverIdentityCounter and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out or  The Structured VDM Discover Identity Command request Message sending fails (no GoodCRC Message received after retries). 8.3.3.25.3.2 PE_SRC_VDM_Identity_ACKed State On entry to the PE_SRC_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. 8.3.3.25.3.3 PE_SRC_VDM_Identity_NAKed State On entry to the PE_SRC_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 949 8.3.3.25.4 Cable Plug Mode Entry/Exit 8.3.3.25.4.1 Cable Plug Structured VDM Enter Mode State Diagram Figure 8.209, "Cable Plug Structured VDM Enter Mode State Diagram" shows the state diagram for a Cable Plug in response to an Enter Mode Command. Figure 8.209 Cable Plug Structured VDM Enter Mode State Diagram 8.3.3.25.4.1.1 PE_CBL_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_CBL_Evaluate_Mode_Entry state from the PE_CBL_Ready state when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_CBL_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_ACK State On entry to the PE_CBL_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Enter Modes request1 PE_CBL_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_CBL_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_CBL_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 950 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.25.4.1.3 PE_CBL_Mode_Entry_NAK State On entry to the PE_CBL_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 951 8.3.3.25.4.2 Cable Plug Structured VDM Exit Mode State Diagram Figure 8.210, "Cable Plug Structured VDM Exit Mode State Diagram" shows the state diagram for a Cable Plug in response to an Exit Mode Command. Figure 8.210 Cable Plug Structured VDM Exit Mode State Diagram 8.3.3.25.4.2.1 PE_CBL_Mode_Exit State The Policy Engine transitions to the PE_CBL_Mode_Exit state from the PE_CBL_Ready state when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_CBL_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_ACK State On entry to the PE_CBL_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. PE_CBL_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Cable = Awake PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_CBL_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Cable = Awake PD = Connected Mode exited PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected PE_CBL_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Cable = Awake PD = Connected DPM says NAK Exit Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 952 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.25.4.2.3 PE_CBL_Mode_Exit_NAK State On entry to the PE_CBL_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 953 8.3.3.26 EPR Mode State Diagrams 8.3.3.26.1 Source EPR Mode Entry State Diagram Figure 8.211, "Source EPR Mode Entry State Diagram" shows the state diagram for an EPR Source in response to an EPR_Mode Message. Figure 8.211 Source EPR Mode Entry State Diagram 8.3.3.26.1.1 PE_SRC_Evaluate_EPR_Mode_Entry State The Policy Engine transitions to the PE_SRC_Evaluate_EPR_Mode_Entry state from the PE_SRC_Ready state when:  An EPR_Mode (Enter) Message is received from the Sink. On Entry to the PE_SRC_Evaluate_EPR_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the EPR_Mode (Enter) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Ack state when:  The Device Policy Manager indicates that EPR Mode can be entered. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Device Policy Manager indicates that the EPR Mode is not to be entered. EPR_Mode (Enter) received PE_SRC_EPR_Mode_Entry_ACK Actions on entry: Send EPR Enter Mode Acknowledge If Source is not the VCONN Source initiate VCONN Swap process PE_SRC_Evaluate_EPR Mode_Entry Actions on entry: Request DPM to evaluate request to enter EPR Mode Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Failed Actions on entry: Send Enter Mode (Enter Failed) with appropriate failure code. DPM says enter EPR Mode EPR Enter Mode (Enter Failed) sent PE_SRC_Ready PE_VCS_Send_Swap PE_VCS_Force_VCONN or PE_VCS_Send_PS_RDY VCONN Swap Process DPM says don’t enter EPR Mode PE_SRC_EPR_Mode_Discover_Cable Actions on entry: Check Vconn Swap Result if Vconn Swap Process carried out. Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected EPR Enter Mode (Enter Acknowledged) Sent & Source is VCONN Source & Unknown Cable PE_INIT_PORT_VDM_Identity_Request PE_INIT_PORT_VDM_Identity_ACKed or PE_INIT_PORT_VDM_Identity_NAKed Source is the VCONN Source Cable Discovery Process PE_SRC_EPR_Mode_Evaluate_Cable_EPR Actions on entry: Ask DPM to evaluate Cable Discovery results Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Succeeded Actions on entry: Send EPR Mode (Enter Succeeded) Enter EPR Mode. Power = Explicit Contract PD = Connected VCONN Swap Process Complete Cable Discovery Process Complete Cable Plug is EPR capable PE_SRC_Send_Capabilities EPR Mode Entered Cable Plug is not EPR capable EPR Enter Mode (Enter Acknowledged) Sent & (captive cable | known EPR Capable Cable) EPR Enter Mode (Enter Acknowledged) Sent & Source is not VCONN Source & Unknown Cable Page 954 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.1.2 PE_SRC_EPR_Mode_Entry_Ack State On entry to the PE_SRC_EPR_Mode_Entry_Ack state the Policy Engine Shall send a EPR_Mode (Enter Acknowledged) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is a captive cable or a known EPR Cable. The Policy Engine Shall transition to the PE_VCS_Send_Swap state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is unknown. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Discover_Cable state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is the VCONN Source and  The cable is unknown. 8.3.3.26.1.3 PE_SRC_EPR_Mode_Discover_Cable State The Policy Engine transitions to the PE_SRC_EPR_Mode_Discover_Cable state from the PE_VCS_Force_VCONN state or PE_VCS_Send_Ps_Rdy state when:  A Source initiated VCONN Swap process has completed. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_Request state in order to perform Cable Plug discovery when:  The Source is the VCONN Source. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The VCONN Swap process failed (the Source is not the VCONN Source). 8.3.3.26.1.4 PE_SRC_EPR_Mode_Evaluate_Cable_EPR State In the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state the Policy Engine requests the DPM to evaluate the Cable Discovery results. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Succeeded state when:  The Cable Plug is capable of EPR Mode. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Cable Plug is not capable of EPR Mode. 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Succeeded State On entry to the PE_SRC_EPR_Mode_Entry_Succeeded state the Policy Engine Shall send a EPR_Mode (Enter Succeeded) Message and enter EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  EPR Mode has been entered. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 955 8.3.3.26.1.6 PE_SRC_EPR_Mode_Entry_Failed State On entry to the PE_SRC_EPR_Mode_Entry_Failed state the Policy Engine Shall send a EPR_Mode (Enter Failed) Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_Mode (Enter Failed) Message has been sent. Page 956 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.2 Sink EPR Mode Entry State Diagram Figure 8.212, "Sink EPR Mode Entry State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode Entry process. Figure 8.212 Sink EPR Mode Entry State Diagram 8.3.3.26.2.1 PE_SNK_Send_EPR_Mode_Entry State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Entry state from the PE_SNK_Ready state when:  The DPM requests entry into EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Entry state the Policy Engine Shall send an EPR_Mode (Enter) Message and starts the SenderResponseTimer and the SinkEPREnterTimer. Note: The SinkEPREnterTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SNK_EPR_Mode_Wait_For_Response state when:  An EPR_Mode (Enter Acknowledge) Message is received. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or DPM Request EPR Mode Entry PE_SNK_EPR_Mode_Entry_Wait_For_Response Actions on entry: Wait for EPR Enter Mode response PE_SNK_Send_EPR Mode_Entry Actions on entry: Send EPR Mode Entry Message Start SenderResponse Timer Start SinkEPREnterTimer Power = Explicit Contract PD = Connected EPR Enter Mode Acknowledge received PE_SNK_Ready EPR Enter Mode Succeeded received Power = Explicit Contract PD = Connected PE_SNK_Send_Soft_Reset EPR Enter Mode received (!Succceded) | SenderResponseTimer timeout | SinkEPREnterTimer timeout EPR Enter Mode received (!Succceded) | SinkEPREnterTimer timeout Actions on exit: Stop the SinkEPRTimer Enter EPR Mode PE_SNK_Wait_For_Capabilities PE_VCS_Evaluate_Swap VCONN Swap Process VCONN_Swap Message Received VCONN Swap Process completed PE_VCS_Turn_Off_VCONN Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 957  The SenderResponseTimer times out or  The SinkEPREnterTimer times out. 8.3.3.26.2.2 PE_SNK_EPR_Mode_Wait_For_Response State In the State the Policy Engine waits for a confirmation that the EPR Mode entry request has succeeded. On exit from the PE_SNK_EPR_Mode_Wait_For_Response state the Policy Engine Shall stop the SinkEPREnterTimer and enter EPR Mode. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or  The SinkEPREnterTimer times out. The Policy Engine Shall transition to the PE_VCS_Evaluate_Swap State when:  A VCONN_Swap Message is received. The Policy Engine Shall transition back from the PE_VCS_Turn_Off_VCONN State to the PE_SNK_EPR_Mode_Wait_For_Response State when:  The VCONN Swap process has completed. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An EPR_Mode (Enter Succeeded) Message has been received. Page 958 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.3 Source EPR Mode Exit State Diagram Figure 8.213, "Source EPR Mode Exit State Diagram" shows the state diagram for an EPR Source initiating the EPR Mode exit process. Figure 8.213 Source EPR Mode Exit State Diagram 8.3.3.26.3.1 PE_SRC_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SRC_Send_EPR_Mode_Exit state from the PE_SRC_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.3.2 PE_SRC_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SRC_EPR_Mode_Exit_Received state from the PE_SRC_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SRC_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SRC_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SRC_Ready Actions on exit: Exit EPR Mode PE_SRC_Send_Capabilities PE_SRC_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explict Contract with SPR PDO & EPR Mode Exited PE_SRC_Hard_Reset Not in an Explicit Contract with an SPR PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 959 8.3.3.26.4 Sink EPR Mode Exit State Diagram Figure 8.214, "Sink EPR Mode Exit State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode exit process. Figure 8.214 Sink EPR Mode Exit State Diagram 8.3.3.26.4.1 PE_SNK_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Exit state from the PE_SNK_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.4.2 PE_SNK_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SNK_EPR_Mode_Exit_Received state from the PE_SNK_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SNK_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SNK_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SNK_Ready Actions on exit: Exit EPR Mode PE_SNK_Wait_for_Capabilities PE_SNK_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explicit Contract with SPR PDO & EPR Mode Exited PE_SNK_Hard_Reset Not in an Explicit Contract with an SPR PDO Page 960 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27 BIST State diagrams 8.3.3.27.1 BIST Carrier Mode State Diagram Figure 8.215, "BIST Carrier Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Carrier Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.215 BIST Carrier Mode State Diagram 8.3.3.27.1.1 PE_BIST_Carrier_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Carrier_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Carrier Mode BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Carrier_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Carrier Mode (see Section 6.4.3.1, "BIST Carrier Mode") and Shall initialize and run the BISTContModeTimer. BIST message received with Data Object BIST Carrier Mode & VBUS = vSafe5V BISTContModeTimer timeout PE_BIST_Carrier_Mode Actions on entry: Tell Protocol Layer to go to BIST Carrier Mode Initialize and run BISTContModeTimer PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 961 The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  The BISTContModeTimer times out. Page 962 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.2 BIST Test Data Mode State Diagram Figure 8.216, "BIST Test Data Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Test Data Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.216 BIST Test Data Mode State Diagram 8.3.3.27.2.1 PE_BIST_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Test Data BIST Data Object and  VBUS is at vSafe5V. BIST message received with Data Object BIST Test Mode & VBUS = vSafe5V Hard Reset PE_BIST_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Test Mode PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 963 On entry to the PE_BIST_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go into BIST Test Data Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A Hard Reset occurs. Page 964 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.3 BIST Shared Capacity Test Mode State Diagram Figure 8.217, "BIST Shared Capacity Test Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Shared Capacity Test Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.217 BIST Shared Capacity Test Mode State Diagram 8.3.3.27.3.1 PE_BIST_Shared_Capacity_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Shared_Capacity_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Shared Test Mode Entry BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Shared_Capacity_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Shared Capacity Test Mode (see Section 6.4.3.3, "BIST Shared Capacity Test Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A BIST Message is received with a BIST Shared Test Mode Exit BIST Data Object. BIST message received with Data Object BIST Shared Test Mode Entry BIST message received with Data Object BIST Shared Test Mode Exit PE_BIST_Shared Capacity_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Shared Capacity Test Mode1. PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected 1) The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off. The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs: Hard Reset, Cable Reset, Soft Reset, Data Role Swap, Power Role Swap, Fast Role Swap, VCONN Swap. The UUT May leave test mode if the tester makes a request that exceeds the capabilities of the UUT. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 965 8.3.3.28 USB Type-C Referenced States This section contains states cross-referenced from the [USB Type-C 2.4] specification. 8.3.3.28.1 ErrorRecovery state The ErrorRecovery state is used to electronically disconnect Port Partners using the USB Type-C connector. The ErrorRecovery state Shall be entered when there are errors on USB Type-C Ports which cannot be recovered by Hard Reset. The ErrorRecovery state Shall map to USB Type-C ErrorRecovery state operation as defined in the [USB Type-C 2.4] specification. Bus powered Sinks Shall Not be required to meet this requirement as removal of their power will serve the same purpose. On entry to the ErrorRecovery state the Explicit Contract and PD Connection Shall be ended. On exit from the ErrorRecovery state a new Explicit Contract Should be established once the Port Partners have re-connected over the CC wire. Page 966 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.29 Policy Engine States Table 8.154, "Policy Engine States" lists the states used by the various state machines. Table 8.154 Policy Engine States State name Reference SenderResponseTimer SRT_Stopped Section 8.3.3.1.1.1 SRT_Running Section 8.3.3.1.1.2 SRT_Expired Section 8.3.3.1.1.3 Source Port PE_SRC_Startup Section 8.3.3.2.1 PE_SRC_Discovery Section 8.3.3.2.2 PE_SRC_Send_Capabilities Section 8.3.3.2.3 PE_SRC_Negotiate_Capability Section 8.3.3.2.4 PE_SRC_Transition_Supply Section 8.3.3.2.5 PE_SRC_Ready Section 8.3.3.2.6 PE_SRC_Disabled Section 8.3.3.2.7 PE_SRC_Capability_Response Section 8.3.3.2.8 PE_SRC_Hard_Reset Section 8.3.3.2.9 PE_SRC_Hard_Reset_Received Section 8.3.3.2.10 PE_SRC_Transition_to_default Section 8.3.3.2.11 PE_SRC_Give_Source_Cap Section 8.3.3.2.15 PE_SRC_Get_Sink_Cap Section 8.3.3.2.12 PE_SRC_Wait_New_Capabilities Section 8.3.3.2.13 PE_SRC_EPR_Keep_Alive Section 8.3.3.2.14 Sink Port PE_SNK_Startup Section 8.3.3.3.1 PE_SNK_Discovery Section 8.3.3.3.2 PE_SNK_Wait_for_Capabilities Section 8.3.3.3.3 PE_SNK_Evaluate_Capability Section 8.3.3.3.4 PE_SNK_Select_Capability Section 8.3.3.3.5 PE_SNK_Transition_Sink Section 8.3.3.3.6 PE_SNK_Ready Section 8.3.3.3.7 PE_SNK_Hard_Reset Section 8.3.3.3.8 PE_SNK_Transition_to_default Section 8.3.3.3.9 PE_SNK_Give_Sink_Cap Section 8.3.3.3.10 PE_SNK_Get_Source_Cap Section 8.3.3.3.12 PE_SNK_EPR_Keep_Alive Section 8.3.3.3.11 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 967 Soft Reset and Protocol Error Source Port Soft Reset PE_SRC_Send_Soft_Reset Section 8.3.3.4.1.1 PE_SRC_Soft_Reset Section 8.3.3.4.1.2 Sink Port Soft Reset PE_SNK_Send_Soft_Reset Section 8.3.3.4.2.1 PE_SNK_Soft_Reset Section 8.3.3.4.2.2 Data Reset DFP Data Reset PE_DDR_Send_Data_Reset Section 8.3.3.5.1.1 PE_DDR_Data_Reset_Received Section 8.3.3.5.1.2 PE_DDR_Wait_For_VCONN_Off Section 8.3.3.5.1.3 PE_DDR_Perform_Data_Reset Section 8.3.3.5.1.4 UFP Data Reset PE_UDR_Send_Data_Reset Section 8.3.3.5.2.1 PE_UDR_Data_Reset_Received Section 8.3.3.5.2.2 PE_UDR_Turn_Off_VCONN Section 8.3.3.5.2.3 PE_UDR_Send_Ps_Rdy Section 8.3.3.5.2.4 PE_UDR_Wait_For_Data_Reset_Complete Section 8.3.3.5.2.5 Not Supported Message Source Port Not Supported PE_SRC_Send_Not_Supported Section 8.3.3.6.1.1 PE_SRC_Not_Supported_Received Section 8.3.3.6.1.2 PE_SRC_Chunk_Received Section 8.3.3.6.1.3 Sink Port Not Supported PE_SNK_Send_Not_Supported Section 8.3.3.6.2.1 PE_SNK_Not_Supported_Received Section 8.3.3.6.2.2 PE_SNK_Chunk_Received Section 8.3.3.6.2.3 Source Alert Source Port Source Alert PE_SRC_Send_Source_Alert Section 8.3.3.7.1.1 PE_SRC_Wait_for_Get_Status Section 8.3.3.7.1.2 Sink Port Source Alert PE_SNK_Source_Alert_Received Section 8.3.3.7.2.1 Sink Port Sink Alert PE_SNK_Send_Sink_Alert Section 8.3.3.7.3.1 PE_SNK_Wait_for_Get_Status Section 8.3.3.7.3.2 Source Port Sink Alert PE_SRC_Sink_Alert_Received Section 8.3.3.7.4.1 Table 8.154 Policy Engine States State name Reference Page 968 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Source/Sink Extended Capabilities Sink Port Get Source Capabilities Extended PE_SNK_Get_Source_Cap_Ext Section 8.3.3.8.1.1 Source Port Give Source Capabilities Extended PE_SRC_Give_Source_Cap_Ext Section 8.3.3.8.2.1 Source Port Get Sink Capabilities Extended PE_SRC_Get_Sink_Cap_Ext Section 8.3.3.8.3.1 Source Port Give Source Capabilities Extended PE_SNK_Give_Sink_Cap_Ext Section 8.3.3.8.4.1 Source Information Sink Port Get Source Information PE_SNK_Get_Source_Info Section 8.3.3.9.1.1 Source Port Give Source Information PE_SRC_Give_Source_Info Section 8.3.3.9.2.1 Status Get Status PE_Get_Status Section 8.3.3.10.1.1 Give Status PE_Give_Status Section 8.3.3.10.1.1 Sink Port Get PPS Status PE_SNK_Get_PPS_Status Section 8.3.3.10.3.1 Source Port Give PPS Status PE_SRC_Give_PPS_Status Section 8.3.3.10.4.1 Battery Capabilities Get Battery Capabilities PE_Get_Battery_Cap Section 8.3.3.11.1.1 Give Battery Capabilities PE_Give_Battery_Cap Section 8.3.3.11.2.1 Battery Status Get Battery Status PE_Get_Battery_Status Section 8.3.3.12.1.1 Give Battery Status PE_Give_Battery_Status Section 8.3.3.12.2.1 Manufacturer Information Get Manufacturer Information PE_Get_Manufacturer_Info Section 8.3.3.13.1.1 Give Manufacturer Information PE_Give_Manufacturer_Info Section 8.3.3.13.2.1 Country Codes and Information Get Country Codes PE_Get_Country_Codes Section 8.3.3.14.1.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 969 Give Country Codes PE_Give_Country_Codes Section 8.3.3.14.2.1 Get Country Information PE_Get_Country_Info Section 8.3.3.14.3.1 Give Country Information PE_Give_Country_Info Section 8.3.3.14.4.1 Revision Get Revision PE_Get_Revision Section 8.3.3.15.1.1 Give Revision PE_Give_Revision Section 8.3.3.15.2.1 Enter USB DFP Enter USB PE_DEU_Send_Enter_USB Section 8.3.3.16.1.1 UFP Enter USB PE_UEU_Enter_USB_Received Section 8.3.3.16.2.1 Security Request/Response Send Security Request PE_Send_Security_Request Section 8.3.3.17.1.1 Send Security Response PE_Send_Security_Response Section 8.3.3.17.2.1 Security Response Received PE_Security_Response_Received Section 8.3.3.17.3.1 Firmware Update Request/Response Send Firmware Update Request PE_Send_Firmware_Update_Request Section 8.3.3.18.1.1 Send Firmware Update Response PE_Send_Firmware_Update_Response Section 8.3.3.18.2.1 Firmware Update Response Received PE_Firmware_Update_Response_Received Section 8.3.3.18.3.1 Dual-Role Port DFP to UFP Data Role Swap PE_DRS_DFP_UFP_Evaluate_Swap Section 8.3.3.19.1.2 PE_DRS_DFP_UFP_Accept_Swap Section 8.3.3.19.1.3 PE_DRS_DFP_UFP_Change_to_UFP Section 8.3.3.19.1.4 PE_DRS_DFP_UFP_Send_Swap Section 8.3.3.19.1.5 PE_DRS_DFP_UFP_Reject_Swap Section 8.3.3.19.1.6 Table 8.154 Policy Engine States State name Reference Page 970 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 UFP to DFP Data Role Swap PE_DRS_UFP_DFP_Evaluate_Swap Section 8.3.3.19.2.2 PE_DRS_UFP_DFP_Accept_Swap Section 8.3.3.19.2.3 PE_DRS_UFP_DFP_Change_to_DFP Section 8.3.3.19.2.4 PE_DRS_UFP_DFP_Send_Swap Section 8.3.3.19.2.5 PE_DRS_UFP_DFP_Reject_Swap Section 8.3.3.19.2.6 Source to Sink Power Role Swap PE_PRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.3.2 PE_PRS_SRC_SNK_Accept_Swap Section 8.3.3.19.3.3 PE_PRS_SRC_SNK_Transition_to_off Section 8.3.3.19.3.4 PE_PRS_SRC_SNK_Assert_Rd Section 8.3.3.19.3.5 PE_PRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.3.6 PE_PRS_SRC_SNK_Send_Swap Section 8.3.3.19.3.7 PE_PRS_SRC_SNK_Reject_Swap Section 8.3.3.19.3.8 Sink to Source Power Role Swap PE_PRS_SNK_SRC_Evaluate_Swap Section 8.3.3.19.4.2 PE_PRS_SNK_SRC_Accept_Swap Section 8.3.3.19.4.3 PE_PRS_SNK_SRC_Transition_to_off Section 8.3.3.19.4.4 PE_PRS_SNK_SRC_Assert_Rp Section 8.3.3.19.4.5 PE_PRS_SNK_SRC_Source_on Section 8.3.3.19.4.6 PE_PRS_SNK_SRC_Send_Swap Section 8.3.3.19.4.7 PE_PRS_SNK_SRC_Reject_Swap Section 8.3.3.19.4.8 Source to Sink Fast Role Swap PE_FRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.5.2 PE_FRS_SRC_SNK_Accept_Swap Section 8.3.3.19.5.3 PE_FRS_SRC_SNK_Transition_to_off Section 8.3.3.19.5.4 PE_FRS_SRC_SNK_Assert_Rd Section 8.3.3.19.5.5 PE_FRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.5.6 Sink to Source Fast Role Swap PE_FRS_SNK_SRC_Start_AMS Section 8.3.3.19.6.1 PE_FRS_SNK_SRC_Send_Swap Section 8.3.3.19.6.2 PE_FRS_SNK_SRC_Transition_to_off Section 8.3.3.19.6.3 PE_FRS_SNK_SRC_VBUS_Applied Section 8.3.3.19.6.4 PE_FRS_SNK_SRC_Assert_Rp Section 8.3.3.19.6.5 PE_FRS_SNK_SRC_Source_on Section 8.3.3.19.6.6 Dual-Role Source Port Get Source Capabilities PE_DR_SRC_Get_Source_Cap Section 8.3.3.19.7.1 Dual-Role Source Port Give Sink Capabilities PE_DR_SRC_Give_Sink_Cap Section 8.3.3.19.8.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 971 Dual-Role Sink Port Get Sink Capabilities PE_DR_SNK_Get_Sink_Cap Section 8.3.3.19.9.1 Dual-Role Sink Port Give Source Capabilities PE_DR_SNK_Give_Source_Cap Section 8.3.3.19.10.1 Dual-Role Source Port Get Source Capabilities Extended PE_DR_SRC_Get_Source_Cap_Ext Section 8.3.3.19.11.1 Dual-Role Sink Port Give Source Capabilities Extended PE_DR_SNK_Give_Source_Cap_Ext Section 8.3.3.19.12.1 Dual-Role Sink Port Get Sink Capabilities Extended PE_DR_SNK_Get_Sink_Cap_Ext Section 8.3.3.19.13.1 Dual-Role Source Port Give Sink Capabilities Extended PE_DR_SRC_Give_Sink_Cap_Ext Section 8.3.3.19.14.1 Dual-Role Source Port Get Source Information PE_DR_SRC_Get_Source_Info Section 8.3.3.19.15.1 Dual-Role Sink Port Give Source Information PE_DR_SNK_Give_Source_Info Section 8.3.3.19.16.1 USB Type-C VCONN Swap PE_VCS_Send_Swap Section 8.3.3.20.1 PE_VCS_Evaluate_Swap Section 8.3.3.20.2 PE_VCS_Accept_Swap Section 8.3.3.20.3 PE_VCS_Reject_Swap Section 8.3.3.20.4 PE_VCS_Wait_For_VCONN Section 8.3.3.20.5 PE_VCS_Turn_Off_VCONN Section 8.3.3.20.6 PE_VCS_Turn_On_VCONN Section 8.3.3.20.7 PE_VCS_Send_Ps_Rdy Section 8.3.3.20.8 PE_VCS_Force_VCONN Section 8.3.3.20.9 Initiator Structured VDM Initiator to Port Structured VDM Discover Identity PE_INIT_PORT_VDM_Identity_Request Section 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_ACKed Section 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_NAKed Section 8.3.3.21.1.3 Initiator Structured VDM Discover SVIDs PE_INIT_VDM_SVIDs_Request Section 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_ACKed Section 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_NAKed Section 8.3.3.21.2.3 Initiator Structured VDM Discover Modes PE_INIT_VDM_Modes_Request Section 8.3.3.21.3.1 PE_INIT_VDM_Modes_ACKed Section 8.3.3.21.3.2 PE_INIT_VDM_Modes_NAKed Section 8.3.3.21.3.3 Table 8.154 Policy Engine States State name Reference Page 972 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Initiator Structured VDM Attention PE_INIT_VDM_Attention_Request Section 8.3.3.21.4.1 Responder Structured VDM Responder Structured VDM Discovery Identity PE_RESP_VDM_Get_Identity Section 8.3.3.22.1.1 PE_RESP_VDM_Send_Identity Section 8.3.3.22.1.2 PE_RESP_VDM_Get_Identity_NAK Section 8.3.3.22.1.3 Responder Structured VDM Discovery SVIDs PE_RESP_VDM_Get_SVIDs Section 8.3.3.22.2.1 PE_RESP_VDM_Send_SVIDs Section 8.3.3.22.2.2 PE_RESP_VDM_Get_SVIDs_NAK Section 8.3.3.22.2.3 Responder Structured VDM Discovery Modes PE_RESP_VDM_Get_Modes Section 8.3.3.22.3.1 PE_RESP_VDM_Send_Modes Section 8.3.3.22.3.2 PE_RESP_VDM_Get_Modes_NAK Section 8.3.3.22.3.3 Receiving a Structured VDM Attention PE_RCV_VDM_Attention_Request Section 8.3.3.22.4.1 DFP Structured VDM DFP Structured VDM Mode Entry PE_DFP_VDM_Mode_Entry_Request Section 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_ACKed Section 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_NAKed Section 8.3.3.23.1.3 DFP Structured VDM Mode Exit PE_DFP_VDM_Mode_Exit_Request Section 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_ACKed Section 8.3.3.23.2.2 UFP Structure VDM UFP Structured VDM Enter Mode PE_UFP_VDM_Evaluate_Mode_Entry Section 8.3.3.24.1.1 PE_UFP_VDM_Mode_Entry_ACK Section 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_NAK Section 8.3.3.24.1.3 UFP Structured VDM Exit Mode PE_UFP_VDM_Mode_Exit Section 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit_ACK Section 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_NAK Section 8.3.3.24.2.3 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 973 Cable Plug Specific Cable Ready PE_CBL_Ready Section 8.3.3.25.1.1 Mode Entry PE_CBL_Evaluate_Mode_Entry Section 8.3.3.25.4.1.1 PE_CBL_Mode_Entry_ACK Section 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_NAK Section 8.3.3.25.4.1.3 Mode Exit PE_CBL_Mode_Exit Section 8.3.3.25.4.2.1 PE_CBL_Mode_Exit_ACK Section 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_NAK Section 8.3.3.25.4.1.3 Cable Soft Reset PE_CBL_Soft_Reset Section 8.3.3.25.2.1.1 Cable Hard Reset PE_CBL_Hard_Reset Section 8.3.3.25.2.2.1 DFP/VCONN Source Soft Reset or Cable Reset PE_DFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Cable_Reset Section 8.3.3.25.2.3.2 UFP/VCONN Source Soft Reset or Cable Reset PE_UFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.4.1 Source Startup Structured VDM Discover Identity PE_SRC_VDM_Identity_Request Section 8.3.3.25.3.1 PE_SRC_VDM_Identity_ACKed Section 8.3.3.25.3.2 PE_SRC_VDM_Identity_NAKed Section 8.3.3.25.3.3 EPR Mode Source EPR Mode Entry PE_SRC_Evaluate_EPR_Mode_Entry Section 8.3.3.26.1.1 PE_SRC_EPR_Mode_Entry_Ack Section 8.3.3.26.1.2 PE_SRC_EPR_Mode_Discover_Cable Section 8.3.3.26.1.3 PE_SRC_EPR_Mode_Evaluate_Cable_EPR Section 8.3.3.26.1.4 PE_SRC_EPR_Mode_Entry_Succeeded Section 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Failed Section 8.3.3.26.1.6 Sink EPR Mode Entry PE_SNK_Send_EPR_Mode_Entry Section 8.3.3.26.2.1 PE_SNK_EPR_Mode_Wait_For_Response Section 8.3.3.26.2.2 Source EPR Mode Exit PE_SRC_Send_EPR_Mode_Exit Section 8.3.3.26.3.1 PE_SRC_EPR_Mode_Exit_Received Section 8.3.3.26.3.2 Table 8.154 Policy Engine States State name Reference Page 974 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Sink EPR Mode Exit PE_SNK_Send_EPR_Mode_Exit Section 8.3.3.26.4.1 PE_SNK_EPR_Mode_Exit_Received Section 8.3.3.26.4.2 BIST BIST Carrier Mode PE_BIST_Carrier_Mode Section 8.3.3.27.1.1 BIST Carrier Mode PE_BIST_Test_Mode Section 8.3.3.27.2.1 BIST Shared Capacity Test Mode PE_BIST_Shared_Capacity_Test_Mode Section 8.3.3.27.3.1 USB Type-C referenced states ErrorRecovery Section 8.3.3.28.1 Table 8.154 Policy Engine States State name Reference
9 - States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 975)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 975 9 States and Status Reporting 9.1 Overview This chapter describes the Status reporting mechanisms for devices with data connections (e.g., D+/D- and or SSTx+/- and SSRx+/-). It also describes the corresponding USB state a device that supports USB PD Shall transition to as a result of changes to the USB PD state that the device is in. This chapter does not define the System Policy or the System Policy Manager. That is defined in [UCSI]. In addition, the Policies themselves are not described here; these are left to the implementers of the relevant products and systems to define. All PD Capable USB (PDUSB) Devices Shall report themselves as self-powered devices (over USB) when plugged into a PD capable Port even if they are entirely powered from VBUS. However, there are some differences between PD and [USB 2.0] / [USB 3.2]; for example, the presence of VBUS alone does not mean that the device (Consumer) moves from the USB Attached State to the USB Powered State. Similarly, the removal of VBUS alone does not move the device (Consumer) from any of the USB states to the USB Attached State. See Section 9.1.2, "Mapping to USB Device States" for details. PDUSB Devices Shall follow the PD requirements when it comes to suspend (see Section 6.4.1.2.1.2, "USB Suspend Supported"), configured, and operational power. The PD requirements when the device is configured or operational are defined in this section (see Table 9.4, "PD Consumer Port Descriptor"). Note: The power requirements reported in the PD Consumer Port descriptor of the device Shall override the power draw reported in the bMaxPower field in the configuration descriptor. A PDUSB Device Shall report zero in the bMaxPower field after successfully negotiating a mutually agreeable Explicit Contract and Shall disconnect and re-enumerate when it switches operation back to operating in standard [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. When operating in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] mode it Shall report its power draw via the bMaxPower field. Each Provider and Consumer will have their own Local Policies which operate between Port Partners. An example of a typical PD system is shown in Figure 9.1, "Example PD Topology". This example consists of a Provider, Consumer/Providers and Consumers connected together in a tree topology. Between directly connected devices there is both a flow of Power and also Communication consisting of both Status and Control information.
9.1 - Overview......................................................................................................................................... (Page 975)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 975 9 States and Status Reporting 9.1 Overview This chapter describes the Status reporting mechanisms for devices with data connections (e.g., D+/D- and or SSTx+/- and SSRx+/-). It also describes the corresponding USB state a device that supports USB PD Shall transition to as a result of changes to the USB PD state that the device is in. This chapter does not define the System Policy or the System Policy Manager. That is defined in [UCSI]. In addition, the Policies themselves are not described here; these are left to the implementers of the relevant products and systems to define. All PD Capable USB (PDUSB) Devices Shall report themselves as self-powered devices (over USB) when plugged into a PD capable Port even if they are entirely powered from VBUS. However, there are some differences between PD and [USB 2.0] / [USB 3.2]; for example, the presence of VBUS alone does not mean that the device (Consumer) moves from the USB Attached State to the USB Powered State. Similarly, the removal of VBUS alone does not move the device (Consumer) from any of the USB states to the USB Attached State. See Section 9.1.2, "Mapping to USB Device States" for details. PDUSB Devices Shall follow the PD requirements when it comes to suspend (see Section 6.4.1.2.1.2, "USB Suspend Supported"), configured, and operational power. The PD requirements when the device is configured or operational are defined in this section (see Table 9.4, "PD Consumer Port Descriptor"). Note: The power requirements reported in the PD Consumer Port descriptor of the device Shall override the power draw reported in the bMaxPower field in the configuration descriptor. A PDUSB Device Shall report zero in the bMaxPower field after successfully negotiating a mutually agreeable Explicit Contract and Shall disconnect and re-enumerate when it switches operation back to operating in standard [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. When operating in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] mode it Shall report its power draw via the bMaxPower field. Each Provider and Consumer will have their own Local Policies which operate between Port Partners. An example of a typical PD system is shown in Figure 9.1, "Example PD Topology". This example consists of a Provider, Consumer/Providers and Consumers connected together in a tree topology. Between directly connected devices there is both a flow of Power and also Communication consisting of both Status and Control information. Page 976 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.1 Example PD Topology Consumer Consumer Consumer/ Provider Consumer/ Provider Provider AC/Battery AC/Battery Power PD Communication P/C P/C P/C P/C Provider/Consumer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 977 Figure 9.2, "Mapping of PD Topology to USB" shows how this same topology can be mapped to USB. Figure 9.2 Mapping of PD Topology to USB Device Device Device Root Hub AC/Battery AC/Battery Power PD Communication Hub Page 978 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 In a USB based system, policy is managed by the host and communication of system level policy information is via standard USB data line communication. This is a separate mechanism to the USB Power Delivery VBUS protocol which is used to manage Local Policy. When USB Communication is used, status information and control requests are passed directly between the System Policy Manager (SPM) on the host and the Provider or Consumer. See Figure 9.3, "Use of SPM in the PD System". Figure 9.3 Use of SPM in the PD System Status information comes from a Provider or Consumer to the SPM so it can better manage the resources on the host and provide feedback to the end user. Real systems will be a mixture of devices which in terms of power management support might have implemented PD, [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] or they might even just be non-compliant “power sucking devices”. The level of communication of system status to the SPM will therefore not necessarily be comprehensive. The aim of the status mechanisms described here is to provide a mechanism whereby each connected entity in the system provides as much information as possible on the status of itself. Information described in this section that is communicated to the SPM is as follows:  Versions of USB Type-C®, PD and BC supported.  Capabilities as a Provider/Consumer.  Current operational state of each Port e.g. Standard, USB Type-C Current, BC, PD and Negotiated power level.  Status of AC or Battery Power for each PDUSB Device in the system. The SPM can Negotiate with Providers or Consumers in the system in order to request a different Local Policy, or to request the amount of power to be delivered by the Provider to the Consumer. Any change in Local Policy could Device Device Device Host (SPM) AC/Battery AC/Battery Power PD Communication USB Communication Hub Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 979 trigger a Re-negotiation of the Explicit Contract, using USB Power Delivery protocols, between a directly connected Provider and Consumer. A change in how much power is available can, for example, cause a Re-negotiation. 9.1.1 PDUSB Device and Hub Requirements All PDUSB Devices Shall return all relevant descriptors mentioned in this chapter. PDUSB Hubs Shall also support a PD bridge as defined in [UCSI]. Page 980 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.2 Mapping to USB Device States As mentioned in Section 9.1, "Overview" a PDUSB Device reports itself as a self-powered device. However, the device Shall determine whether or not it is in the USB Attached State or USB Powered States as described in Figure 9.4, "USB Attached to USB Powered State Transition", Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" and Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" All other USB states of the PDUSB Device Shall be as described in Chapter 9 of [USB 2.0] and [USB 3.2]. Figure 9.4, "USB Attached to USB Powered State Transition" shows how a PDUSB Device determines when to transition from the USB Attached State to the USB Powered State. USB Type-C Dead Battery operation does not require special handling since the default state at Attach or after a Hard Reset is that the USB Device is a Sink. Figure 9.4 USB Attached to USB Powered State Transition Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Consumer. A PDUSB Device determines that it is performing a Power Role Swap as described in Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present No Yes Can enumerate? Yes Device is a Source? Attached Sink? USB Attached Yes Device in Sink Mode No Negotiate enough Power? No USB Powered No No Yes Device in Source Mode (5V) Yes Hard Reset Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 981 Figure 9.5 Any USB State to USB Attached State Transition (When operating as a Consumer) Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Provider. Figure 9.6 Any USB State to USB Attached State Transition (When operating as a Provider) Figure 9.7, "Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap)" shows how a PDUSB Device using the USB Type-C connector determines when to transition from the USB Powered State to the USB Attached State after a Data Role Swap has been performed i.e., it has just changed from operation as a PDUSB Host to operation as a PDUSB Device. The Data Role Swap is described in Section 6.3.9, "DR_Swap Message". A Hard Reset will also return a Sink acting as a PDUSB Host to PDUSB Device operation as described in Section 6.8.3, "Hard Reset". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present Yes No Swapping Power Roles? Any USB State USB Attached Yes No Hard Reset and Can Operate Hard Reset and Can’t Operate Hard Reset and Bus Powered Lack of PD comms? No Yes Any USB State USB Attached Local Power Source Lost Hard Reset Page 982 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.7 Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap) VBUS Present Yes Swapping Data Roles? Any USB State USB Attached No Yes Hard Reset Changes Data Role Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 983 9.1.3 PD Software Stack Figure 9.8, "Software stack on a PD aware OS" gives an example of the software stack on a PD aware OS. In this stack we are using the example of a system with an xHCI based controller. The USB Power Delivery hardware May or May Not be a part of the xHC. Figure 9.8 Software stack on a PD aware OS Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager Page 984 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.4 PDUSB Device Enumeration As described earlier, a PDUSB Device acts as a self-powered device with some caveats with respect to how it transitions from the USB Attached State to USB Powered State. Figure 9.9, "Enumeration of a PDUSB Device" gives a high-level overview of the enumeration steps involved due to this change. A PDUSB Device will first (Step1) interact with the Power Delivery hardware and the Local Policy manager to determine whether or not it can get sufficient power to enumerate/operate. PD is likely to have established a Explicit Contract prior to enumeration. The SPM will be notified (Step 2) of the result of this Negotiation between the Power Delivery hardware and the PDUSB Device. After successfully negotiating a mutually agreeable Explicit Contract the device will signal a connect to the xHC. The standard USB enumeration process (Steps 3, 4 and 5) is then followed to load the appropriate driver for the function(s) that the PDUSB Device exposes. Figure 9.9 Enumeration of a PDUSB Device If a PDUSB Device cannot perform its intended function with the amount of power that it can get from the Port it is connected to, then the host system Should display a notification (on a PD aware OS) about the failure to provide sufficient power to the device. In addition, the device Shall follow the requirements listed in Section 8.2.5.2.1, "Local device handling of mismatch". Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager 5 4 3 2 1
9.2 - PD Specific Descriptors............................................................................................................ (Page 985)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 985 9.2 PD Specific Descriptors A PDUSB Device Shall return all relevant descriptors mentioned in this section. The device Shall return its capability descriptors as part of the device's Binary Object Store (BOS) descriptor set. Table 9.1, "USB Power Delivery Type Codes" lists the type of PD device capabilities. Table 9.1 USB Power Delivery Type Codes Capability Code Value Description POWER_DELIVERY_CAPABILITY 06H Defines the various PD Capabilities of this device BATTERY_INFO_CAPABILITY 07H Provides information on each Battery supported by the device PD_CONSUMER_PORT_CAPABILITY 08H The Consumer characteristics of a Port on the device PD_PROVIDER_PORT_CAPABILITY 09H The Provider characteristics of a Port on the device Page 986 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.1 USB Power Delivery Capability Descriptor Table 9.2, "USB Power Delivery Capability Descriptor" details the fields in the USB POWER_DELIVERY_CAPABILITY Descriptor. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: POWER_DELIVERY_CAPABILITY 3 bReserved 1 Reserved Shall be set to zero. 4 bmAttributes 4 Bitmap Bitmap encoding of supported device level features. A value of one in a bit location indicates a feature is supported; a value of zero indicates it is not supported. Encodings are: Bit Description 0 Reserved. Shall be set to zero. 1 Battery Charging. This bit Shall be set to one to indicate this device supports [USBBC 1.2] as per the value reported in the bcdBCVersion field. 2 USB Power Delivery. This bit Shall be set to one to indicate this device supports the USB Power Delivery Specification as per the value reported in the bcdPDVersion field. 3 Provider. This bit Shall be set to one to indicate this device is capable of providing power. This field is only Valid if Bit 2 is set to one. 4 Consumer. This bit Shall be set to one to indicate that this device is a consumer of power. This field is only Valid if Bit 2 is set to one. 5 This bit Shall be set to 1 to indicate that this device supports the feature CHARGING_POLICY. Note: Supporting the CHARGING_POLICY feature does not require a BC or PD mechanism to be implemented. 6 USB Type-C Current. This bit Shall be set to one to indicate this device supports power capabilities defined in[USB Type-C 2.4] as per the value reported in the bcdUSBTypeCVersion field 7 Reserved. Shall be set to zero. 15:8 bmPowerSource. At least one of the following bits 8, 9 and 14 Shall be set to indicate which power sources are supported. Bit Description 8 AC Supply 9 Battery 10 Other 13:11 NumBatteries. This field Shall only be Valid when the Battery field is set to one and Shall be used to report the number of batteries in the device. 14 Uses VBUS 15 Reserved and Shall be set to zero. 13:16 Reserved. Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 987 9.2.2 Battery Info Capability Descriptor A PDUSB Device Shall support the capability descriptor shown in Table 9.3, "Battery Info Capability Descriptor" if it reported that one of its power sources was a Battery in the bmPowerSource field in its Power Deliver Capability Descriptor. It Shall return one BATTERY_INFO_CAPABILITY Descriptor per Battery it supports. 8 bcdBCVersion 2 BCD Battery Charging Specification Release Number in Binary-Coded Decimal (e.g., V1.20 is 120H). This field Shall only be Valid if the device indicates that it supports [USBBC 1.2] in the bmAttributes field. 10 bcdPDVersion 2 BCD USB Power Delivery Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports PD in the bmAttributes field. 12 bcdUSBTypeCVersion 2 BCD USB Type-C Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports USB Type-C in the bmAttributes field. Table 9.3 Battery Info Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: BATTERY_INFO_CAPABILITY 3 iBattery 1 Index Index of string descriptor Shall contain the user-friendly name for this Battery. 4 iSerial 1 Index Index of string descriptor Shall contain the Serial Number String for this Battery. 5 iManufacturer 1 Index Index of string descriptor Shall contain the name of the Manufacturer for this Battery. 6 bBatteryId 1 Number Value Shall be used to uniquely identify this Battery in status Messages. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 dwChargedThreshold 4 mWh Shall contain the Battery charge value above which this Battery is considered to be fully charged but not necessarily “topped off.” 12 dwWeakThreshold 4 mWh Shall contain the minimum charge level of this Battery such that above this threshold, a device can be assured of being able to power up successfully (see [USBBC 1.2]). 16 dwBatteryDesignCapacity 4 mWh Shall contain the design capacity of the Battery. 20 dwBatteryLastFullchargeCapacity 4 mWh Shall contain the maximum capacity of the Battery when fully charged. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description Page 988 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.3 PD Consumer Port Capability Descriptor A PDUSB Device Shall support the PD_CONSUMER_PORT_CAPABILITY descriptor shown in Table 9.4, "PD Consumer Port Descriptor" if it is a Consumer. Table 9.4 PD Consumer Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_CONSUMER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Consumer Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 wMinVoltage 2 Number Shall contain the minimum voltage in 50mV units that this Consumer is capable of operating at. 8 wMaxVoltage 2 Number Shall contain the maximum voltage in 50mV units that this Consumer is capable of operating at. 10 wReserved 2 Number Reserved and Shall be set to zero. 12 dwMaxOperatingPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw when it is in a steady state operating mode. 16 dwMaxPeakPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw for a short duration of time (dwMaxPeakPowerTime) before it falls back into a steady state. 20 dwMaxPeakPowerTime 4 Number Shall contain the time in 100ms units that this Consumer can draw peak current. A device Shall set this field to 0xFFFF if this value is unknown. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 989 9.2.4 PD Provider Port Capability Descriptor A PDUSB Device Shall support the PD_PROVIDER_PORT_CAPABILITY descriptor shown in Table 9.5, "PD Provider Port Descriptor" if it is a Provider. Table 9.5 PD Provider Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_PROVIDER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Provider Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 bNumOfPDObjects 1 Number Shall indicate the number of Power Data Objects. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 wPowerDataObject1 4 Bitmap Shall contain the first Power Data Object supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. ... ... ... ... ... 4*(N+1) wPowerDataObjectN 4 Bitmap Shall contain the 2nd and subsequent Power Data Objects supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects.
9.3 - PD Specific Requests and Events.......................................................................................... (Page 990)
Page 990 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.3 PD Specific Requests and Events A PDUSB Device that is compliant to this specification Shall support the Battery related requests if it has a Battery. A PDUSB Hub that is compliant to this specification Shall support a USB PD Bridge as described in [UCSI] irrespective of whether the PDUSB Hub is a Provider, a Consumer, or both. 9.3.1 PD Specific Requests PD defines requests to which PDUSB Devices Shall respond as outlined in Table 9.6, "PD Requests". All Valid requests in Table 9.6, "PD Requests" Shall be implemented by PDUSB Devices. Table 9.7, "PD Request Codes" gives the bRequest values for Commands that are not listed in the hub/device framework chapters of [USB 2.0], [USB 3.2]. Table 9.8, "PD Feature Selectors" gives the Valid feature selectors for the PD class. Refer to Section 9.4.2.1, "BATTERY_WAKE_MASK Feature Selector", and Section 9.4.2.2, "CHARGING_POLICY Feature Selector" for a description of the features. Table 9.6 PD Requests Request bmRequestType bRequest wValue wIndex wLength Data GetBatteryStatus 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status SetPDFeature 00000000B set_feature Feature Selector Feature Specific Zero None Table 9.7 PD Request Codes bRequest Value GET_BATTERY_STATUS 21 Table 9.8 PD Feature Selectors Feature Selector Recipient Value BATTERY_WAKE_MASK Device 40 CHARGING_POLICY Device 54
9.4 - PDUSB Hub and PDUSB Peripheral Device Requests.................................................. (Page 991)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 991 9.4 PDUSB Hub and PDUSB Peripheral Device Requests 9.4.1 GetBatteryStatus The request shown in Table 9.9, "Get Battery Status Request" returns the current status of the Battery in a PDUSB Hub/Peripheral, with Battery Status information as shown in Table 9.10, "Battery Status Structure". Table 9.9 Get Battery Status Request bmRequestType bRequest wValue wIndex wLength Data 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status Table 9.10 Battery Status Structure Offset Field Size Value Description 0 bBatteryAttributes 1 Number Shall indicate whether a Battery is installed and whether this is charging or discharging. Value Description 0 There is no Battery 1 The Battery is charging 2 The Battery is discharging 3 The Battery is neither discharging nor charging 255...4 Reserved and Shall Not be used 1 bBatterySOC 1 Number Shall indicate the Battery State of Charge given as percentage value from Battery Remaining Capacity. 2 bBatteryStatus 1 Number If a Battery is present Shall indicate the present status of the Battery. Value Description 0 No error 1 Battery required and not present 2 Battery non-chargeable/wrong chemistry 3 Over-temp shutdown 4 Over-voltage shutdown 5 Over-current shutdown 6 Fatigued Battery 7 Unspecified error 255...8 Reserved and Shall Not be used
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Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 17 7.1.14 Non-application of VBUS Slew Rate Limits ...................................................................................................332 7.1.15 VCONN Power Cycle ................................................................................................................................................333 7.2 Sink Requirements..................................................................................................................... 335 7.2.1 Behavioral Aspects ................................................................................................................................................335 7.2.2 Sink Bulk Capacitance ..........................................................................................................................................335 7.2.3 Sink Standby .............................................................................................................................................................335 7.2.4 Suspend Power Consumption ...........................................................................................................................336 7.2.5 Zero Negotiated Current .....................................................................................................................................336 7.2.6 Transient Load Behavior ....................................................................................................................................336 7.2.7 Swap Standby for Sinks .......................................................................................................................................336 7.2.8 Sink Peak Current Operation ............................................................................................................................336 7.2.9 Robust Sink Operation .........................................................................................................................................337 7.2.10 Fast Role Swap .........................................................................................................................................................338 7.3 Transitions..................................................................................................................................... 339 7.3.1 Transitions caused by a Request Message ..................................................................................................340 7.3.2 Transitions Caused by Power Role Swap ....................................................................................................388 7.3.3 Transitions Caused by Hard Reset ..................................................................................................................396 7.3.4 Transitions Caused by Fast Role Swap .........................................................................................................400 7.4 Electrical Parameters................................................................................................................ 404 7.4.1 Source Electrical Parameters ............................................................................................................................404 7.4.2 Sink Electrical Parameters .................................................................................................................................413 7.4.3 Common Electrical Parameters .......................................................................................................................415 8 Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416 8.1 Overview......................................................................................................................................... 416 8.2 Device Policy Manager.............................................................................................................. 417 8.2.1 Capabilities ................................................................................................................................................................418 8.2.2 System Policy ...........................................................................................................................................................418 8.2.3 Control of Source/Sink ........................................................................................................................................419 8.2.4 Cable Detection .......................................................................................................................................................419 8.2.5 Managing Power Requirements .......................................................................................................................420 8.2.6 Use of "Unconstrained Power" bit with Batteries and AC supplies ..................................................421 8.2.7 Interface to the Policy Engine ...........................................................................................................................423 8.3 Policy Engine................................................................................................................................. 424 8.3.1 Introduction ..............................................................................................................................................................424 8.3.2 Atomic Message Sequence Diagrams ............................................................................................................425 8.3.3 State Diagrams .........................................................................................................................................................822 9 States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975 9.1 Overview......................................................................................................................................... 975 9.1.1 PDUSB Device and Hub Requirements .........................................................................................................979 9.1.2 Mapping to USB Device States ..........................................................................................................................980 9.1.3 PD Software Stack ..................................................................................................................................................983 9.1.4 PDUSB Device Enumeration ..............................................................................................................................984 9.2 PD Specific Descriptors ............................................................................................................ 985 9.2.1 USB Power Delivery Capability Descriptor .................................................................................................986 9.2.2 Battery Info Capability Descriptor ..................................................................................................................987 9.2.3 PD Consumer Port Capability Descriptor ....................................................................................................988 9.2.4 PD Provider Port Capability Descriptor .......................................................................................................989 9.3 PD Specific Requests and Events.......................................................................................... 990 9.3.1 PD Specific Requests .............................................................................................................................................990 9.4 PDUSB Hub and PDUSB Peripheral Device Requests.................................................. 991 9.4.1 GetBatteryStatus .....................................................................................................................................................991 9.4.2 SetPDFeature ...........................................................................................................................................................992 10 Power Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995 Page 18 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.1 Introduction .................................................................................................................................. 995 10.2 Source Power Rules ................................................................................................................... 995 10.2.1 Source Power Rule Considerations ................................................................................................................996 10.2.2 Normative Voltages and Currents ...................................................................................................................997 10.2.3 Optional Voltages/Currents ............................................................................................................................1005 10.3 Sink Power Rules ...................................................................................................................... 1013 10.3.1 Sink Power Rule Considerations ..................................................................................................................1013 10.3.2 Normative Sink Rules ........................................................................................................................................1013 A CRC calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1015 A.1 C code example .......................................................................................................................... 1015 B Message Sequence Examples (Deprecated) . . . . . . . . . . . . . . . . . . . . . . . 1016 C VDM Command Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1017 C.1 Discover Identity Example.................................................................................................... 1017 C.1.1 Discover Identity Command request ..........................................................................................................1017 C.1.2 Discover Identity Command response - Active Cable. ........................................................................1018 C.1.3 Discover Identity Command response - Hub. .........................................................................................1020 C.2 Discover SVIDs Example........................................................................................................ 1021 C.2.1 Discover SVIDs Command request ..............................................................................................................1021 C.2.2 Discover SVIDs Command response ...........................................................................................................1022 C.3 Discover Modes Example....................................................................................................... 1023 C.3.1 Discover Modes Command request .............................................................................................................1023 C.3.2 Discover Modes Command response .........................................................................................................1024 C.4 Enter Mode Example ............................................................................................................... 1025 C.4.1 Enter Mode Command request .....................................................................................................................1025 C.4.2 Enter Mode Command response ..................................................................................................................1026 C.4.3 Enter Mode Command request with additional VDO. .........................................................................1027 C.5 Exit Mode Example................................................................................................................... 1028 C.5.1 Exit Mode Command request .........................................................................................................................1028 C.5.2 Exit Mode Command response ......................................................................................................................1029 C.6 Attention Example.................................................................................................................... 1030 C.6.1 Attention Command request ..........................................................................................................................1030 C.6.2 Attention Command request with additional VDO. ..............................................................................1031 D BMC Receiver Design Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1032 D.1 Finite Difference Scheme....................................................................................................... 1032 D.1.1 Sample Circuitry ..................................................................................................................................................1032 D.1.2 Theory ......................................................................................................................................................................1032 D.1.3 Data Recovery .......................................................................................................................................................1034 D.1.4 Noise Zone and Detection Zone ....................................................................................................................1035 D.2 Subtraction Scheme ................................................................................................................. 1036 D.2.1 Sample Circuitry ..................................................................................................................................................1036 D.2.2 Output of Each Circuit Block ..........................................................................................................................1036 D.2.3 Subtractor Output at Power Source and Power Sink ..........................................................................1036 D.2.4 Noise Zone and Detection Zone ....................................................................................................................1037 E FRS System Level Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1038 E.1 Overview....................................................................................................................................... 1038 E.2 FRS Initial Setup ........................................................................................................................ 1041 E.3 FRS Process ................................................................................................................................. 1044 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 19 List of Figures 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34 2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 Figure 2.1 Logical Structure of USB Power Delivery Capable Devices..............................................................55 Figure 2.2 Example SOP' Communication between VCONN Source and Cable Plug(s) ...............................58 Figure 2.3 USB Power Delivery Communications Stack..........................................................................................67 Figure 2.4 USB Power Delivery Communication Over USB ...................................................................................68 Figure 2.5 High Level Architecture View ....................................................................................................................... 69 Figure 2.6 Example of a Normal EPR Mode Operational Flow.............................................................................74 3 USB Type-A and USB Type-B Cable Assemblies and Connectors . . . . . .77 4 Electrical Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78 5 Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79 Figure 5.1 Interpretation of ordered sets......................................................................................................................81 Figure 5.2 Transmit Order for Various Sizes of Data................................................................................................83 Figure 5.3 USB Power Delivery Packet Format...........................................................................................................84 Figure 5.4 CRC-32 Generation ............................................................................................................................................88 Figure 5.5 Line format of Hard Reset...............................................................................................................................89 Figure 5.6 Line format of Cable Reset..............................................................................................................................90 Figure 5.7 BMC Example .......................................................................................................................................................92 Figure 5.8 BMC Transmitter Block Diagram.................................................................................................................92 Figure 5.9 BMC Receiver Block Diagram........................................................................................................................93 Figure 5.10 BMC Encoded Start of Preamble..................................................................................................................93 Figure 5.11 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition.....................................................................................................................................................94 Figure 5.12 Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to-Low Last Transition.....................................................................................................................................................94 Figure 5.13 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition.....................................................................................................................................................95 Figure 5.14 Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition .............................................................................................................................................................. 95 Figure 5.15 BMC Tx 'ONE' Mask ...........................................................................................................................................96 Figure 5.16 BMC Tx 'ZERO' Mask.........................................................................................................................................97 Figure 5.17 BMC Rx 'ONE' Mask when Sourcing Power.............................................................................................99 Figure 5.18 BMC Rx 'ZERO' Mask when Sourcing Power........................................................................................100 Figure 5.19 BMC Rx 'ONE' Mask when Power neutral..............................................................................................100 Figure 5.20 BMC Rx 'ZERO' Mask when Power neutral ...........................................................................................101 Figure 5.21 BMC Rx 'ONE' Mask when Sinking Power .............................................................................................101 Figure 5.22 BMC Rx 'ZERO' Mask when Sinking Power...........................................................................................102 Figure 5.23 Transmitter Load Model for BMC Tx from a Source .........................................................................103 Figure 5.24 Transmitter Load Model for BMC Tx from a Sink ..............................................................................103 Figure 5.25 Transmitter diagram illustrating zDriver..............................................................................................107 Figure 5.26 Inter-Frame Gap Timings..............................................................................................................................108 Figure 5.27 Example Multi-Drop Configuration showing two DRPs..................................................................111 Figure 5.28 Example Multi-Drop Configuration showing a DFP and UFP........................................................111 Figure 5.29 Test Frame...........................................................................................................................................................113 6 Protocol Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Figure 6.1 USB Power Delivery Packet Format for a Control Message...........................................................115 Figure 6.2 USB Power Delivery Packet Format including Data Message Payload .....................................116 Figure 6.3 USB Power Delivery Packet Format including an Extended Message Header and Payload 116 Page 20 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.4 Example Security_Request sequence Unchunked (Chunked bit = 0)........................................123 Figure 6.5 Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero)...........................................................................................................................................................123 Figure 6.6 Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero)......................................................................................................................................................124 Figure 6.7 Example Security_Request sequence Chunked (Chunked bit = 1)..............................................125 Figure 6.8 Example Security_Request Message of Data Size 7 (Chunked bit set to 1).............................126 Figure 6.9 Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1)126 Figure 6.10 Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1).............................................................................................................................................................127 Figure 6.11 Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1)127 Figure 6.12 SPR Capabilities Message Construction..................................................................................................152 Figure 6.13 Example Capabilities Message with 2 Power Data Objects............................................................152 Figure 6.14 BIST Message .....................................................................................................................................................159 Figure 6.15 Vendor Defined Message...............................................................................................................................162 Figure 6.16 Discover Identity Command response....................................................................................................169 Figure 6.17 Discover Identity Command response for a DRD...............................................................................169 Figure 6.18 Example Discover SVIDs response with 3 SVIDs................................................................................186 Figure 6.19 Example Discover SVIDs response with 4 SVIDs................................................................................187 Figure 6.20 Example Discover SVIDs response with 12 SVIDs followed by an empty response...........187 Figure 6.21 Example Discover Modes response for a given SVID with 3 Modes ..........................................188 Figure 6.22 Successful Enter Mode sequence...............................................................................................................189 Figure 6.23 Unsuccessful Enter Mode sequence due to NAK.................................................................................190 Figure 6.24 Exit Mode sequence.........................................................................................................................................191 Figure 6.25 Attention Command request/response sequence.............................................................................192 Figure 6.26 Command request/response sequence..................................................................................................193 Figure 6.27 Enter/Exit Mode Process..............................................................................................................................195 Figure 6.28 Battery_Status Message.................................................................................................................................196 Figure 6.29 Alert Message.....................................................................................................................................................198 Figure 6.30 Get_Country_Info Message ...........................................................................................................................201 Figure 6.31 Enter_USB Message .........................................................................................................................................203 Figure 6.32 EPR_Request Message....................................................................................................................................205 Figure 6.33 EPR Mode DO Message...................................................................................................................................206 Figure 6.34 Illustration of process to enter EPR Mode.............................................................................................208 Figure 6.35 Source_Info Message.......................................................................................................................................212 Figure 6.36 Revision Message Data Object....................................................................................................................214 Figure 6.37 Source_Capabilities_Extended Message .................................................................................................216 Figure 6.38 SOP Status Message.........................................................................................................................................221 Figure 6.39 SOP'/SOP'' Status Message...........................................................................................................................226 Figure 6.40 Get_Battery_Cap Message .............................................................................................................................227 Figure 6.41 Get_Battery_Status Message ........................................................................................................................227 Figure 6.42 Battery_Capabilities Message......................................................................................................................228 Figure 6.43 Get_Manufacturer_Info Message................................................................................................................230 Figure 6.44 Manufacturer_Info Message.........................................................................................................................231 Figure 6.45 Security_Request Message............................................................................................................................233 Figure 6.46 Security_Response Message ........................................................................................................................233 Figure 6.47 Firmware_Update_Request Message .......................................................................................................234 Figure 6.48 Firmware_Update_Response Message....................................................................................................234 Figure 6.49 PPS_Status Message.........................................................................................................................................235 Figure 6.50 Country_Codes Message................................................................................................................................237 Figure 6.51 Country_Info Message ....................................................................................................................................238 Figure 6.52 Sink_Capabilities_Extended Message.......................................................................................................239 Figure 6.53 Extended_Control Message ..........................................................................................................................244 Figure 6.54 Mapping SPR Capabilities to EPR Capabilities.....................................................................................245 Figure 6.55 EPR_Source_Capabilities message with no EPR PDOs .....................................................................246 Figure 6.56 Vendor_Defined_Extended Message ........................................................................................................247 Figure 6.57 Outline of States................................................................................................................................................275 Figure 6.58 References to states.........................................................................................................................................275 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 21 Figure 6.59 Chunking architecture Showing Message and Control Flow.........................................................277 Figure 6.60 Chunked Rx State Diagram...........................................................................................................................278 Figure 6.61 Chunked Tx State Diagram...........................................................................................................................281 Figure 6.62 Chunked Message Router State Diagram...............................................................................................284 Figure 6.63 Common Protocol Layer Message Transmission State Diagram.................................................286 Figure 6.64 Source Protocol Layer Message Transmission State Diagram......................................................289 Figure 6.65 Sink Protocol Layer Message Transmission State Diagram...........................................................291 Figure 6.66 Protocol layer Message reception.............................................................................................................293 Figure 6.67 Hard/Cable Reset.............................................................................................................................................295 7 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312 Figure 7.1 Placement of Source Bulk Capacitance...................................................................................................312 Figure 7.2 Transition Envelope for Positive Voltage Transitions .....................................................................313 Figure 7.3 Transition Envelope for Negative Voltage Transitions....................................................................314 Figure 7.4 PPS Positive Voltage Transitions...............................................................................................................315 Figure 7.5 PPS Negative Voltage Transitions............................................................................................................316 Figure 7.6 SPR PPS Programmable Voltage and Current Limit..........................................................................318 Figure 7.7 SPR PPS Constant Power...............................................................................................................................319 Figure 7.8 AVS Positive Voltage Transitions ..............................................................................................................321 Figure 7.9 AVS Negative Voltage Transitions.............................................................................................................321 Figure 7.10 Source VBUS and VCONN Response to Hard Reset................................................................................323 Figure 7.11 Application of vSrcNew and vSrcValid limits after tSrcReady......................................................325 Figure 7.12 Expected AVS/PPS Ripple Relative to an LSB......................................................................................326 Figure 7.13 Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode.....................327 Figure 7.14 Source Peak Current Overload ...................................................................................................................329 Figure 7.15 Holdup Time Measurement.........................................................................................................................330 Figure 7.16 VBUS Power during Fast Role Swap ..........................................................................................................331 Figure 7.17 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min)......................................................................................................................................................332 Figure 7.18 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min)......................................................................................................................................................332 Figure 7.19 Data Reset UFP VCONN Power Cycle .........................................................................................................333 Figure 7.20 Data Reset DFP VCONN Power Cycle .........................................................................................................334 Figure 7.21 Placement of Sink Bulk Capacitance ........................................................................................................335 Figure 7.22 Transition Diagram for Increasing the Voltage...................................................................................342 Figure 7.23 Transition Diagram for Increasing the Voltage and Current.........................................................345 Figure 7.24 Transition Diagram for Increasing the Voltage and Decreasing the Current.........................348 Figure 7.25 Transition Diagram for Decreasing the Voltage and Increasing the Current.........................351 Figure 7.26 Transition Diagram for Decreasing the Voltage..................................................................................354 Figure 7.27 Transition Diagram for Decreasing the Voltage and the Current................................................357 Figure 7.28 Transition Diagram for no change in Current or Voltage...............................................................360 Figure 7.29 Transition Diagram for Increasing the Current ..................................................................................362 Figure 7.30 Transition Diagram for Decreasing the Current.................................................................................365 Figure 7.31 Transition Diagram for Increasing the Programmable Power Supply Voltage.....................368 Figure 7.32 Transition Diagram for Decreasing the Programmable Power Supply Voltage ...................371 Figure 7.33 Transition Diagram for increasing the Current in PPS mode........................................................374 Figure 7.34 Transition Diagram for decreasing the Current in PPS mode.......................................................377 Figure 7.35 Transition Diagram for no change in Current or Voltage in PPS mode....................................380 Figure 7.36 Transition Diagram for Increasing the Adjustable Power Supply Voltage..............................382 Figure 7.37 Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage..........................385 Figure 7.38 Transition Diagram for no change in Current or Voltage in AVS mode....................................387 Figure 7.39 Transition Diagram for a Sink Requested Power Role Swap ........................................................389 Figure 7.40 Transition Diagram for a Source Requested Power Role Swap...................................................393 Figure 7.41 Transition Diagram for a Source Initiated Hard Reset.....................................................................397 Figure 7.42 Transition Diagram for a Sink Initiated Hard Reset..........................................................................399 Figure 7.43 Transition Diagram for Fast Role Swap..................................................................................................401 Page 22 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416 Figure 8.1 Example of daisy chained displays ...........................................................................................................422 Figure 8.2 Basic Message Exchange (Successful).....................................................................................................426 Figure 8.3 Basic Message flow indicating possible errors....................................................................................427 Figure 8.4 Basic Message Flow with Bad followed by a Retry............................................................................428 Figure 8.5 Successful Fixed, Variable or Battery SPR Power Negotiation.....................................................448 Figure 8.6 Rejected Fixed, Variable or Battery SPR Power Negotiation.........................................................452 Figure 8.7 Wait response to Fixed, Variable or Battery SPR Power Negotiation.......................................455 Figure 8.8 SPR PPS Keep Alive..........................................................................................................................................458 Figure 8.9 SPR Sink Makes Request (Accept) ............................................................................................................461 Figure 8.10 SPR Sink Makes Request (Reject)..............................................................................................................464 Figure 8.11 SPR Sink Makes Request (Wait).................................................................................................................467 Figure 8.12 Entering EPR Mode (Success).....................................................................................................................470 Figure 8.13 Entering EPR Mode (Failure due to non-EPR cable).........................................................................473 Figure 8.14 Entering EPR Mode (Failure of VCONN Swap).......................................................................................476 Figure 8.15 Successful Fixed EPR Power Negotiation ..............................................................................................480 Figure 8.16 Rejected Fixed EPR Power Negotiation..................................................................................................484 Figure 8.17 Wait response to Fixed EPR Power Negotiation.................................................................................487 Figure 8.18 EPR Keep Alive ..................................................................................................................................................490 Figure 8.19 Exiting EPR Mode (Sink Initiated) ............................................................................................................493 Figure 8.20 Exiting EPR Mode (Source Initiated).......................................................................................................496 Figure 8.21 EPR Sink Makes Request (Accept)............................................................................................................499 Figure 8.22 EPR Sink Makes Request (Reject) .............................................................................................................502 Figure 8.23 EPR Sink Makes Request (Wait) ................................................................................................................505 Figure 8.24 Unsupported message....................................................................................................................................508 Figure 8.25 Soft Reset .............................................................................................................................................................511 Figure 8.26 DFP Initiated Data Reset where the DFP is the VCONN Source......................................................514 Figure 8.27 DFP Receives Data Reset where the DFP is the VCONN Source .....................................................517 Figure 8.28 DFP Initiated Data Reset where the UFP is the VCONN Source......................................................520 Figure 8.29 DFP Receives a Data Reset where the UFP is the VCONN Source..................................................524 Figure 8.30 Source initiated Hard Reset.........................................................................................................................528 Figure 8.31 Sink Initiated Hard Reset..............................................................................................................................531 Figure 8.32 Source initiated reset - Sink long reset...................................................................................................534 Figure 8.33 Successful Power Role Swap Sequence Initiated by the Source..................................................538 Figure 8.34 Rejected Power Role Swap Sequence Initiated by the Source......................................................542 Figure 8.35 Power Role Swap Sequence with wait Initiated by the Source....................................................545 Figure 8.36 Successful Power Role Swap Sequence Initiated by the Sink .......................................................549 Figure 8.37 Rejected Power Role Swap Sequence Initiated by the Sink...........................................................553 Figure 8.38 Power Role Swap Sequence with wait Initiated by the Sink.........................................................556 Figure 8.39 Successful Fast Role Swap Sequence .......................................................................................................560 Figure 8.40 Data Role Swap, UFP operating as Sink initiates................................................................................564 Figure 8.41 Rejected Data Role Swap, UFP operating as Sink initiates.............................................................567 Figure 8.42 Data Role Swap with Wait, UFP operating as Sink initiates...........................................................570 Figure 8.43 Data Role Swap, UFP operating as Source initiates...........................................................................573 Figure 8.44 Rejected Data Role Swap, UFP operating as Source initiates........................................................576 Figure 8.45 Data Role Swap with Wait, UFP operating as Source initiates .....................................................579 Figure 8.46 Data Role Swap, DFP operating as Source initiates...........................................................................582 Figure 8.47 Rejected Data Role Swap, DFP operating as Source initiates........................................................585 Figure 8.48 Data Role Swap with Wait, DFP operating as Source initiates .....................................................588 Figure 8.49 Data Role Swap, DFP operating as Sink initiates................................................................................591 Figure 8.50 Rejected Data Role Swap, DFP operating as Sink initiates.............................................................594 Figure 8.51 Data Role Swap with Wait, DFP operating as Sink initiates...........................................................597 Figure 8.52 Successful VCONN Source Swap, initiated by VCONN Source.........................................................600 Figure 8.53 Rejected VCONN Source Swap, initiated by VCONN Source.............................................................603 Figure 8.54 VCONN Source Swap with Wait, initiated by VCONN Source.............................................................606 Figure 8.55 VCONN Source Swap, initiated by non-VCONN Source.........................................................................609 Figure 8.56 Rejected VCONN Source Swap, initiated by non-VCONN Source......................................................612 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 23 Figure 8.57 VCONN Source Swap with Wait....................................................................................................................615 Figure 8.58 Source Alert to Sink.........................................................................................................................................618 Figure 8.59 Sink Alert to Source.........................................................................................................................................620 Figure 8.60 Sink Gets Source Status..................................................................................................................................622 Figure 8.61 Source Gets Sink Status..................................................................................................................................625 Figure 8.62 VCONN Source Gets Cable Plug Status.......................................................................................................628 Figure 8.63 Sink Gets Source PPS Status.........................................................................................................................631 Figure 8.64 Sink Gets Source's Capabilities...................................................................................................................634 Figure 8.65 Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source ...............................................637 Figure 8.66 Source Gets Sink's Capabilities...................................................................................................................640 Figure 8.67 Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink ....................................................643 Figure 8.68 Sink Gets Source's EPR Capabilities.........................................................................................................646 Figure 8.69 Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source...................................649 Figure 8.70 Source Gets Sink's EPR Capabilities.........................................................................................................652 Figure 8.71 Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink........................................655 Figure 8.72 Sink Gets Source's Extended Capabilities..............................................................................................658 Figure 8.73 Dual-Role Source Gets Dual-Role Sink's Extended Capabilities...................................................661 Figure 8.74 Source Gets Sink's Extended Capabilities..............................................................................................664 Figure 8.75 Dual-Role Sink Gets Dual-Role Source's Extended Capabilities...................................................667 Figure 8.76 Sink Gets Source's Battery Capabilities ..................................................................................................670 Figure 8.77 Source Gets Sink's Battery Capabilities ..................................................................................................673 Figure 8.78 Sink Gets Source's Battery Status..............................................................................................................676 Figure 8.79 Source Gets Sink's Battery Status..............................................................................................................679 Figure 8.80 Source Gets Sink's Port Manufacturer Information ..........................................................................682 Figure 8.81 Sink Gets Source's Port Manufacturer Information ..........................................................................685 Figure 8.82 Source Gets Sink's Battery Manufacturer Information....................................................................688 Figure 8.83 Sink Gets Source's Battery Manufacturer Information....................................................................691 Figure 8.84 VCONN Source Gets Cable Plug's Manufacturer Information..........................................................694 Figure 8.85 Source Gets Sink's Country Codes.............................................................................................................697 Figure 8.86 Sink Gets Source's Country Codes.............................................................................................................700 Figure 8.87 VCONN Source Gets Cable Plug's Country Codes..................................................................................703 Figure 8.88 Source Gets Sink's Country Information................................................................................................706 Figure 8.89 Sink Gets Source's Country Information................................................................................................709 Figure 8.90 VCONN Source Gets Cable Plug's Country Information .....................................................................712 Figure 8.91 Source Gets Sink's Revision Information...............................................................................................715 Figure 8.92 Sink Gets Source's Revision Information...............................................................................................718 Figure 8.93 VCONN Source Gets Cable Plug's Revision Information ....................................................................721 Figure 8.94 Sink Gets Source's Information..................................................................................................................724 Figure 8.95 Dual-Role Source Gets Dual-Role Sink's Information as a Source...............................................727 Figure 8.96 Source requests security exchange with Sink......................................................................................730 Figure 8.97 Sink requests security exchange with Source......................................................................................733 Figure 8.98 VCONN Source requests security exchange with Cable Plug...........................................................736 Figure 8.99 Source requests firmware update exchange with Sink ...................................................................739 Figure 8.100 Sink requests firmware update exchange with Source ...................................................................742 Figure 8.101 VCONN Source requests firmware update exchange with Cable Plug.........................................745 Figure 8.102 Initiator to Responder Discover Identity (ACK).................................................................................748 Figure 8.103 Initiator to Responder Discover Identity (NAK).................................................................................751 Figure 8.104 Initiator to Responder Discover Identity (BUSY)...............................................................................754 Figure 8.105 Initiator to Responder Discover SVIDs (ACK) .....................................................................................757 Figure 8.106 Initiator to Responder Discover SVIDs (NAK).....................................................................................760 Figure 8.107 Initiator to Responder Discover SVIDs (BUSY)...................................................................................763 Figure 8.108 Initiator to Responder Discover Modes (ACK)....................................................................................766 Figure 8.109 Initiator to Responder Discover Modes (NAK) ...................................................................................769 Figure 8.110 Initiator to Responder Discover Modes (BUSY)..................................................................................772 Figure 8.111 DFP to UFP Enter Mode.................................................................................................................................775 Figure 8.112 DFP to UFP Exit Mode.....................................................................................................................................778 Figure 8.113 DFP to Cable Plug Enter Mode....................................................................................................................781 Figure 8.114 DFP to Cable Plug Exit Mode .......................................................................................................................784 Page 24 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.115 Initiator to Responder Attention...............................................................................................................787 Figure 8.116 BIST Carrier Mode Test .................................................................................................................................789 Figure 8.117 BIST Test Data Test .........................................................................................................................................792 Figure 8.118 BIST Share Capacity Mode Test..................................................................................................................795 Figure 8.119 UFP Entering USB4 Mode (Accept)...........................................................................................................798 Figure 8.120 UFP Entering USB4 Mode (Reject)............................................................................................................801 Figure 8.121 UFP Entering USB4 Mode (Wait)...............................................................................................................804 Figure 8.122 Cable Plug Entering USB4 Mode (Accept) .............................................................................................807 Figure 8.123 Cable Plug Entering USB4 Mode (Reject)...............................................................................................810 Figure 8.124 Cable Plug Entering USB4 Mode (Wait)..................................................................................................813 Figure 8.125 Unstructured VDM Message Sequence ...................................................................................................816 Figure 8.126 VDEM Message Sequence..............................................................................................................................819 Figure 8.127 Outline of States................................................................................................................................................822 Figure 8.128 References to states.........................................................................................................................................823 Figure 8.129 Example of state reference with conditions .........................................................................................823 Figure 8.130 Example of state reference with the same entry and exit ..............................................................823 Figure 8.131 SenderResponseTimer Policy Engine State Diagram.......................................................................825 Figure 8.132 Source Port State Diagram ...........................................................................................................................827 Figure 8.133 Sink Port State Diagram.................................................................................................................................835 Figure 8.134 SOP Source Port Soft Reset and Protocol Error State Diagram....................................................841 Figure 8.135 Sink Port Soft Reset and Protocol Error Diagram..............................................................................843 Figure 8.136 DFP Data_Reset Message State Diagram................................................................................................845 Figure 8.137 UFP Data_Reset Message State Diagram ................................................................................................847 Figure 8.138 Source Port Not Supported Message State Diagram.........................................................................850 Figure 8.139 Sink Port Not Supported Message State Diagram..............................................................................852 Figure 8.140 Source Port Source Alert State Diagram.................................................................................................854 Figure 8.141 Sink Port Source Alert State Diagram......................................................................................................855 Figure 8.142 Sink Port Sink Alert State Diagram...........................................................................................................856 Figure 8.143 Source Port Sink Alert State Diagram......................................................................................................857 Figure 8.144 Sink Port Get Source Capabilities Extended State Diagram...........................................................858 Figure 8.145 Source Give Source Capabilities Extended State Diagram..............................................................859 Figure 8.146 Source Port Get Sink Capabilities Extended State Diagram...........................................................860 Figure 8.147 Sink Give Sink Capabilities Extended State Diagram........................................................................861 Figure 8.148 Sink Port Get Source Information State Diagram...............................................................................862 Figure 8.149 Source Give Source Information State Diagram..................................................................................863 Figure 8.150 Get Status State Diagram...............................................................................................................................864 Figure 8.151 Give Status State Diagram.............................................................................................................................865 Figure 8.152 Sink Port Get Source PPS Status State Diagram..................................................................................866 Figure 8.153 Source Give Source PPS Status State Diagram.....................................................................................867 Figure 8.154 Get Battery Capabilities State Diagram...................................................................................................868 Figure 8.155 Give Battery Capabilities State Diagram ................................................................................................869 Figure 8.156 Get Battery Status State Diagram..............................................................................................................870 Figure 8.157 Give Battery Status State Diagram............................................................................................................871 Figure 8.158 Get Manufacturer Information State Diagram.....................................................................................872 Figure 8.159 Give Manufacturer Information State Diagram...................................................................................873 Figure 8.160 Get Country Codes State Diagram.............................................................................................................874 Figure 8.161 Give Country Codes State Diagram...........................................................................................................875 Figure 8.162 Get Country Information State Diagram.................................................................................................876 Figure 8.163 Give Country Information State Diagram ..............................................................................................877 Figure 8.164 Get Revision State Diagram..........................................................................................................................878 Figure 8.165 Give Revision State Diagram .......................................................................................................................879 Figure 8.166 DFP Enter_USB Message State Diagram .................................................................................................880 Figure 8.167 UFP Enter_USB Message State Diagram .................................................................................................881 Figure 8.168 Send security request State Diagram.......................................................................................................882 Figure 8.169 Send security response State Diagram....................................................................................................883 Figure 8.170 Security response received State Diagram............................................................................................884 Figure 8.171 Send firmware update request State Diagram ....................................................................................885 Figure 8.172 Send firmware update response State Diagram.................................................................................886 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 25 Figure 8.173 Firmware update response received State Diagram.........................................................................887 Figure 8.174 DFP to UFP Data Role Swap State Diagram...........................................................................................888 Figure 8.175 UFP to DFP Data Role Swap State Diagram...........................................................................................891 Figure 8.176 Dual-Role Port in Source to Sink Power Role Swap State Diagram............................................894 Figure 8.177 Dual-role Port in Sink to Source Power Role Swap State Diagram.............................................898 Figure 8.178 Dual-Role Port in Source to Sink Fast Role Swap State Diagram.................................................902 Figure 8.179 Dual-role Port in Sink to Source Fast Role Swap State Diagram..................................................906 Figure 8.180 Dual-Role (Source) Get Source Capabilities diagram .......................................................................909 Figure 8.181 Dual-Role (Source) Give Sink Capabilities diagram ..........................................................................910 Figure 8.182 Dual-Role (Sink) Get Sink Capabilities State Diagram......................................................................911 Figure 8.183 Dual-Role (Sink) Give Source Capabilities State Diagram ..............................................................912 Figure 8.184 Dual-Role (Source) Get Source Capabilities Extended State Diagram ......................................913 Figure 8.185 Dual-Role (Sink) Give Source Capabilities Extended diagram......................................................914 Figure 8.186 Dual-Role (Sink) Get Sink Capabilities Extended State Diagram.................................................915 Figure 8.187 Dual-Role (Source) Give Sink Capabilities Extended diagram......................................................916 Figure 8.188 Dual-Role (Source) Get Source Information State Diagram ..........................................................917 Figure 8.189 Dual-Role (Source) Give Source Information diagram ....................................................................918 Figure 8.190 VCONN Swap State Diagram ..........................................................................................................................919 Figure 8.191 Initiator to Port VDM Discover Identity State Diagram...................................................................922 Figure 8.192 Initiator VDM Discover SVIDs State Diagram ......................................................................................924 Figure 8.193 Initiator VDM Discover Modes State Diagram.....................................................................................926 Figure 8.194 Initiator VDM Attention State Diagram ..................................................................................................928 Figure 8.195 Responder Structured VDM Discover Identity State Diagram .....................................................929 Figure 8.196 Responder Structured VDM Discover SVIDs State Diagram..........................................................930 Figure 8.197 Responder Structured VDM Discover Modes State Diagram........................................................931 Figure 8.198 Receiving a Structured VDM Attention State Diagram ....................................................................932 Figure 8.199 DFP VDM Mode Entry State Diagram ......................................................................................................933 Figure 8.200 DFP VDM Mode Exit State Diagram..........................................................................................................935 Figure 8.201 UFP Structured VDM Enter Mode State Diagram...............................................................................937 Figure 8.202 UFP Structured VDM Exit Mode State Diagram...................................................................................939 Figure 8.203 Cable Ready State Diagram..........................................................................................................................941 Figure 8.204 Cable Plug Soft Reset State Diagram........................................................................................................942 Figure 8.205 Cable Plug Hard Reset State Diagram......................................................................................................943 Figure 8.206 DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram.........944 Figure 8.207 UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram .......................................946 Figure 8.208 Source Startup Structured VDM Discover Identity State Diagram .............................................947 Figure 8.209 Cable Plug Structured VDM Enter Mode State Diagram..................................................................949 Figure 8.210 Cable Plug Structured VDM Exit Mode State Diagram .....................................................................951 Figure 8.211 Source EPR Mode Entry State Diagram ..................................................................................................953 Figure 8.212 Sink EPR Mode Entry State Diagram........................................................................................................956 Figure 8.213 Source EPR Mode Exit State Diagram......................................................................................................958 Figure 8.214 Sink EPR Mode Exit State Diagram...........................................................................................................959 Figure 8.215 BIST Carrier Mode State Diagram.............................................................................................................960 Figure 8.216 BIST Test Data Mode State Diagram ........................................................................................................962 Figure 8.217 BIST Shared Capacity Test Mode State Diagram ................................................................................964 9 States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975 Figure 9.1 Example PD Topology ....................................................................................................................................976 Figure 9.2 Mapping of PD Topology to USB................................................................................................................977 Figure 9.3 Use of SPM in the PD System.......................................................................................................................978 Figure 9.4 USB Attached to USB Powered State Transition.................................................................................980 Figure 9.5 Any USB State to USB Attached State Transition (When operating as a Consumer)..........981 Figure 9.6 Any USB State to USB Attached State Transition (When operating as a Provider).............981 Figure 9.7 Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap)..982 Figure 9.8 Software stack on a PD aware OS..............................................................................................................983 Figure 9.9 Enumeration of a PDUSB Device................................................................................................................984 Page 26 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10 Power Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995 Figure 10.1 SPR Source Power Rule Illustration for Fixed Supply PDOs.......................................................1000 Figure 10.2 SPR Source Power Rule Example For Fixed Supply PDOs...........................................................1001 Figure 10.3 Valid SPR AVS Operating Region for a Source advertising in the range of 27W < PDP ≤ 45W 1003 Figure 10.4 Valid SPR AVS Operating Region for a Source advertising in the range of 45W < PDP ≤ 60W 1003 Figure 10.5 Valid SPR AVS Operating Region for a Source advertising in the range of 60W < PDP ≤ 100W...................................................................................................................................................................1004 Figure 10.6 Valid EPR AVS Operating Region............................................................................................................1011 Figure 10.7 EPR Source Power Rule Illustration for Fixed PDOs......................................................................1012 A CRC calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1015 B Message Sequence Examples (Deprecated) . . . . . . . . . . . . . . . . . . . . . . . 1016 C VDM Command Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1017 D BMC Receiver Design Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1032 Figure D.1 Circuit Block of BMC Finite Difference Receiver..............................................................................1032 Figure D.2 BMC AC and DC noise from VBUS at Power Sink...............................................................................1033 Figure D.3 Sample BMC Signals (a) without USB 2.0 SE0 Noise (b) with USB 2.0 SE0 Noise.............1033 Figure D.4 Scaled BMC Signal Derivative with 50ns Sampling Rate (a) without USB 2.0 Noise (b) with USB 2.0 Noise ..................................................................................................................................................1034 Figure D.5 BMC Signal and Finite Difference Output with Various Time Steps........................................1034 Figure D.6 Output of Finite Difference in dash line and Edge Detector in solid line..............................1035 Figure D.7 Noise Zone and Detect Zone of BMC Receiver..................................................................................1035 Figure D.8 Circuit Block of BMC Subtraction Receiver........................................................................................1036 Figure D.9 (a) Output of LPF1 and LPF2 (b) Subtraction of LPF1 and LPF2 Output..............................1036 Figure D.10 Output of the BMC LPF1 in blue dash curve and the Subtractor in red solid curve (a) at Power Source (b) at Power Sink.............................................................................................................1037 E FRS System Level Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1038 Figure E.1 Example FRS Capable System..................................................................................................................1038 Figure E.2 Slow VBUS Discharge ....................................................................................................................................1039 Figure E.3 Fast VBUS Discharge......................................................................................................................................1040 Figure E.4 Slow VBUS discharge after FR_Swap message is sent.....................................................................1044 Figure E.5 VBUS discharges quickly before FR_Swap message is sent after adapter disconnected.1046 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 27 List of Tables Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 LIMITED COPYRIGHT LICENSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 INTELLECTUAL PROPERTY DISCLAIMER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Table Of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13 List of Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19 List of Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34 Table 1.1 Section Overview....................................................................................................................................................36 Table 1.2 Keywords ...................................................................................................................................................................37 Table 1.3 Document References...........................................................................................................................................39 Table 1.4 Terms and Abbreviations.................................................................................................................................... 40 2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53 Table 2.1 Fixed Supply Power Ranges...............................................................................................................................75 Table 2.2 PPS Voltage Power Ranges.................................................................................................................................75 Table 2.3 AVS Voltage Power Ranges ................................................................................................................................ 76 3 USB Type-A and USB Type-B Cable Assemblies and Connectors . . . . . .77 4 Electrical Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .78 5 Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79 Table 5.1 4b5b Symbol Encoding ........................................................................................................................................80 Table 5.2 Ordered Sets .............................................................................................................................................................81 Table 5.3 Validation of Ordered Sets.................................................................................................................................. 82 Table 5.4 Data Size .....................................................................................................................................................................83 Table 5.5 SOP Ordered Set......................................................................................................................................................84 Table 5.6 SOP’ Ordered Set.....................................................................................................................................................85 Table 5.7 SOP’’ Ordered Set....................................................................................................................................................85 Table 5.8 SOP’_Debug Ordered Set......................................................................................................................................86 Table 5.9 SOP’’_Debug Ordered Set.....................................................................................................................................86 Table 5.10 CRC-32 Mapping .....................................................................................................................................................88 Table 5.11 Hard Reset Ordered Set .......................................................................................................................................89 Table 5.12 Cable Reset Ordered Set ......................................................................................................................................90 Table 5.13 Rp values used for Collision Avoidance.........................................................................................................91 Table 5.14 BMC Tx Mask Definition, X Values................................................................................................................... 97 Table 5.15 BMC Tx Mask Definition, Y Values................................................................................................................... 98 Table 5.16 BMC Rx Mask Definition....................................................................................................................................102 Table 5.17 BMC Common Normative Requirements...................................................................................................105 Table 5.18 BMC Transmitter Normative Requirements.............................................................................................106 Table 5.19 BMC Receiver Normative Requirements....................................................................................................110 6 Protocol Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114 Table 6.1 Message Header ....................................................................................................................................................116 Table 6.2 Revision Interoperability during an Explicit Contract.........................................................................119 Table 6.3 Extended Message Header................................................................................................................................120 Table 6.4 Use of Unchunked Message Supported bit................................................................................................122 Table 6.5 Control Message Types ......................................................................................................................................128 Page 28 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.6 Data Message Types ............................................................................................................................................138 Table 6.7 Power Data Object................................................................................................................................................139 Table 6.8 Augmented Power Data Object.......................................................................................................................140 Table 6.9 Fixed Supply PDO – Source ..............................................................................................................................141 Table 6.10 Fixed Power Source Peak Current Capability ..........................................................................................143 Table 6.11 Variable Supply (non-Battery) PDO – Source ..........................................................................................143 Table 6.12 Battery Supply PDO – Source ..........................................................................................................................144 Table 6.13 SPR Programmable Power Supply APDO – Source................................................................................145 Table 6.14 SPR Adjustable Voltage Supply APDO – Source.......................................................................................146 Table 6.15 EPR Adjustable Voltage Supply APDO – Source......................................................................................146 Table 6.16 EPR AVS Power Source Peak Current Capability....................................................................................147 Table 6.17 Fixed Supply PDO – Sink....................................................................................................................................148 Table 6.18 Variable Supply (non-Battery) PDO – Sink................................................................................................149 Table 6.19 Battery Supply PDO – Sink................................................................................................................................150 Table 6.20 SPR Programmable Power Supply APDO – Sink.....................................................................................150 Table 6.21 SPR Adjustable Voltage Supply APDO – Sink............................................................................................151 Table 6.22 EPR Adjustable Voltage Supply APDO – Sink ...........................................................................................151 Table 6.23 Fixed and Variable Request Data Object ....................................................................................................155 Table 6.24 Battery Request Data Object............................................................................................................................156 Table 6.25 PPS Request Data Object ...................................................................................................................................156 Table 6.26 AVS Request Data Object...................................................................................................................................156 Table 6.27 BIST Data Object ...................................................................................................................................................160 Table 6.28 Unstructured VDM Header...............................................................................................................................163 Table 6.29 Structured VDM Header ....................................................................................................................................164 Table 6.30 Structured VDM Commands ............................................................................................................................165 Table 6.31 SVID Values .............................................................................................................................................................165 Table 6.32 Commands and Responses...............................................................................................................................167 Table 6.33 ID Header VDO.......................................................................................................................................................169 Table 6.34 Product Types (UFP)...........................................................................................................................................170 Table 6.35 Product Types (Cable Plug/VPD) ..................................................................................................................171 Table 6.36 Product Types (DFP)...........................................................................................................................................171 Table 6.37 Cert Stat VDO..........................................................................................................................................................172 Table 6.38 Product VDO ...........................................................................................................................................................172 Table 6.39 UFP VDO ...................................................................................................................................................................172 Table 6.40 DFP VDO ...................................................................................................................................................................175 Table 6.41 Passive Cable VDO................................................................................................................................................176 Table 6.42 Active Cable VDO1................................................................................................................................................179 Table 6.43 Active Cable VDO2................................................................................................................................................180 Table 6.44 VPD VDO...................................................................................................................................................................184 Table 6.45 Discover SVIDs Responder VDO.....................................................................................................................186 Table 6.46 Battery Status Data Object (BSDO)...............................................................................................................196 Table 6.47 Alert Data Object (ADO).....................................................................................................................................198 Table 6.48 Country Code Data Object (CCDO)................................................................................................................201 Table 6.49 Enter_USB Data Object (EUDO)......................................................................................................................203 Table 6.50 EPR Mode Data Object (EPRMDO)................................................................................................................206 Table 6.51 Source_Info Data Object (SIDO)......................................................................................................................212 Table 6.52 Revision Message Data Object (RMDO)......................................................................................................214 Table 6.53 Extended Message Types..................................................................................................................................215 Table 6.54 Source Capabilities Extended Data Block (SCEDB) ...............................................................................216 Table 6.55 SOP Status Data Block (SDB)...........................................................................................................................221 Table 6.56 “SOP’/SOP’’ Status Data Block (SPDB)”......................................................................................................226 Table 6.57 Get Battery Cap Data Block (GBCDB)...........................................................................................................227 Table 6.58 Get Battery Status Data Block (GBSDB)......................................................................................................227 Table 6.59 Battery Capability Data Block (BCDB)”......................................................................................................228 Table 6.60 Get Manufacturer Info Data Block (GMIDB) .............................................................................................230 Table 6.61 Manufacturer Info Data Block (MIDB) ........................................................................................................231 Table 6.62 PPS Status Data Block (PPSSDB)...................................................................................................................235 Table 6.63 Country Codes Data Block (CCDB)................................................................................................................237 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 29 Table 6.64 Country Info Data Block (CIDB) .....................................................................................................................238 Table 6.65 Sink Capabilities Extended Data Block (SKEDB)...................................................................................239 Table 6.66 Extended Control Data Block (ECDB)..........................................................................................................244 Table 6.67 Extended Control Message Types .................................................................................................................244 Table 6.68 Time Values.............................................................................................................................................................262 Table 6.69 Timers........................................................................................................................................................................264 Table 6.70 Counter Parameters ............................................................................................................................................267 Table 6.71 Counters ...................................................................................................................................................................267 Table 6.72 Response to an incoming Message (except VDM)..................................................................................269 Table 6.73 Response to an incoming VDM.......................................................................................................................269 Table 6.74 Message Discarding.............................................................................................................................................274 Table 6.75 Protocol Layer States..........................................................................................................................................298 Table 6.76 Message Applicability Abbreviations...........................................................................................................300 Table 6.77 Applicability of Control Messages.................................................................................................................301 Table 6.78 Applicability of Data Messages.......................................................................................................................303 Table 6.79 Applicability of Extended Messages.............................................................................................................305 Table 6.80 Applicability of Extended Control Messages ............................................................................................308 Table 6.81 Applicability of Structured VDM Commands............................................................................................309 Table 6.82 Applicability of Reset Signaling......................................................................................................................310 Table 6.83 Applicability of Fast Role Swap Request....................................................................................................310 Table 6.84 Value Parameters .................................................................................................................................................311 7 Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312 Table 7.1 Sequence Description for Increasing the Voltage...................................................................................343 Table 7.2 Sequence Diagram for Increasing the Voltage and Current...............................................................346 Table 7.3 Sequence Description for Increasing the Voltage and Decreasing the Current ........................349 Table 7.4 Sequence Description for Decreasing the Voltage and Increasing the Current ........................352 Table 7.5 Sequence Description for Decreasing the Voltage .................................................................................355 Table 7.6 Sequence Description for Decreasing the Voltage and the Current ...............................................358 Table 7.7 Sequence Description for no change in Current or Voltage...............................................................360 Table 7.8 Sequence Description for Increasing the Current..................................................................................363 Table 7.9 Sequence Description for Decreasing the Current.................................................................................366 Table 7.10 Sequence Description for Increasing the Programmable Power Supply Voltage ....................369 Table 7.11 Sequence Description for Decreasing the Programmable Power Supply Voltage...................372 Table 7.12 Sequence Description for increasing the Current in PPS mode .......................................................375 Table 7.13 Sequence Description for decreasing the Current in PPS mode ......................................................378 Table 7.14 Sequence Description for no change in Current or Voltage in PPS mode....................................380 Table 7.15 Sequence Description for Increasing the Adjustable Voltage Supply Voltage...........................383 Table 7.16 Sequence Description for Decreasing the Adjustable Voltage Supply Voltage..........................386 Table 7.17 Sequence Description for no change in Current or Voltage in AVS mode ...................................387 Table 7.18 Sequence Description for a Sink Requested Power Role Swap........................................................390 Table 7.19 Sequence Description for a Source Requested Power Role Swap...................................................394 Table 7.20 Sequence Description for a Source Initiated Hard Reset ....................................................................397 Table 7.21 Sequence Description for a Sink Initiated Hard Reset .........................................................................399 Table 7.22 Sequence Description for Fast Role Swap .................................................................................................402 Table 7.23 Source Electrical Parameters..........................................................................................................................404 Table 7.24 Sink Electrical Parameters ...............................................................................................................................413 Table 7.25 Common Source/Sink Electrical Parameters...........................................................................................415 8 Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416 Table 8.1 Basic Message Flow.............................................................................................................................................426 Table 8.2 Potential issues in Basic Message Flow ......................................................................................................427 Table 8.3 Basic Message Flow with CRC failure ..........................................................................................................429 Table 8.4 Atomic Message Sequences..............................................................................................................................430 Table 8.5 AMS: Power Negotiation (SPR) ......................................................................................................................431 Table 8.6 AMS: Power Negotiation (EPR)......................................................................................................................432 Table 8.7 AMS: Unsupported Message ............................................................................................................................434 Page 30 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.8 AMS: Soft Reset......................................................................................................................................................434 Table 8.9 AMS: Data Reset ....................................................................................................................................................434 Table 8.10 AMS: Power Role Swap ......................................................................................................................................435 Table 8.11 AMS: Fast Role Swap...........................................................................................................................................435 Table 8.12 AMS: Data Role Swap..........................................................................................................................................436 Table 8.13 AMS: VCONN Swap.................................................................................................................................................437 Table 8.14 AMS: Alert................................................................................................................................................................437 Table 8.15 AMS: Status..............................................................................................................................................................438 Table 8.16 AMS: Source/Sink Capabilities (SPR) ..........................................................................................................438 Table 8.17 AMS: Source/Sink Capabilities (EPR)..........................................................................................................439 Table 8.18 AMS: Extended Capabilities .............................................................................................................................440 Table 8.19 AMS: Battery Capabilities..................................................................................................................................440 Table 8.20 AMS: Manufacturer Information....................................................................................................................441 Table 8.21 AMS: Country Codes............................................................................................................................................441 Table 8.22 AMS: Country Information ...............................................................................................................................441 Table 8.23 AMS: Revision Information ..............................................................................................................................442 Table 8.24 AMS: Source Information..................................................................................................................................442 Table 8.25 AMS: Security .........................................................................................................................................................442 Table 8.26 AMS: Firmware Update......................................................................................................................................443 Table 8.27 AMS: Structured VDM.........................................................................................................................................444 Table 8.28 AMS: Built-In Self-Test (BIST).........................................................................................................................445 Table 8.29 AMS: Enter USB .....................................................................................................................................................445 Table 8.30 AMS: Unstructured VDM ...................................................................................................................................445 Table 8.31 AMS: Hard Reset ...................................................................................................................................................446 Table 8.32 Steps for a successful Power Negotiation..................................................................................................449 Table 8.33 Steps for a rejected Power Negotiation ......................................................................................................453 Table 8.34 Steps for a Wait response to a Power Negotiation.................................................................................456 Table 8.35 Steps for SPR PPS Keep Alive ..........................................................................................................................459 Table 8.36 Steps for SPR Sink Makes Request (Accept).............................................................................................462 Table 8.37 Steps for SPR Sink Makes Request (Reject) ..............................................................................................465 Table 8.38 Steps for SPR Sink Makes Request (Wait) .................................................................................................468 Table 8.39 Steps for Entering EPR Mode (Success)......................................................................................................471 Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) .........................................................474 Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) .......................................................................477 Table 8.42 Steps for a successful EPR Power Negotiation ........................................................................................481 Table 8.43 Steps for a Rejected EPR Power Negotiation............................................................................................485 Table 8.44 Steps for a Wait response to an EPR Power Negotiation....................................................................488 Table 8.45 Steps for EPR Keep Alive...................................................................................................................................491 Table 8.46 Steps for Exiting EPR Mode (Sink Initiated).............................................................................................494 Table 8.47 Steps for Exiting EPR Mode (Source Initiated)........................................................................................497 Table 8.48 Steps for EPR Sink Makes Request (Accept).............................................................................................500 Table 8.49 Steps for EPR Sink Makes Request (Reject)..............................................................................................503 Table 8.50 Steps for SPR Sink Makes Request (Wait) .................................................................................................506 Table 8.51 Steps for an Unsupported Message ..............................................................................................................509 Table 8.52 Steps for a Soft Reset...........................................................................................................................................512 Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source...................................515 Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource..............................518 Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source...................................521 Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source.............................525 Table 8.57 Steps for Source initiated Hard Reset..........................................................................................................529 Table 8.58 Steps for Sink initiated Hard Reset...............................................................................................................532 Table 8.59 Steps for Source initiated Hard Reset - Sink long reset .......................................................................535 Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence .............................................539 Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence.................................................543 Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence...............................................546 Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence...................................................550 Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence ......................................................554 Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence....................................................557 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 31 Table 8.66 Steps for a Successful Fast Role Swap Sequence ....................................................................................561 Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates.................................................................565 Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates..............................................568 Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates ...........................................571 Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates............................................................574 Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates.........................................577 Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates......................................580 Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates............................................................583 Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates ........................................586 Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates......................................589 Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates.................................................................592 Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates..............................................595 Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates ...........................................598 Table 8.79 Steps for Source to Sink VCONN Source Swap ...........................................................................................601 Table 8.80 Steps for Rejected VCONN Source Swap.......................................................................................................604 Table 8.81 Steps for VCONN Source Swap with Wait.....................................................................................................607 Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source.........................................................610 Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source......................................613 Table 8.84 Steps for VCONN Source Swap with Wait.....................................................................................................616 Table 8.85 Steps for Source Alert to Sink..........................................................................................................................619 Table 8.86 Steps for Sink Alert to Source..........................................................................................................................621 Table 8.87 Steps for a Sink getting Source Status Sequence.....................................................................................623 Table 8.88 Steps for a Source getting Sink Status Sequence.....................................................................................626 Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence..........................................................629 Table 8.90 Steps for a Sink getting Source PPS status Sequence............................................................................632 Table 8.91 Steps for a Sink getting Source Capabilities Sequence.........................................................................635 Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence...638 Table 8.93 Steps for a Source getting Sink Capabilities Sequence.........................................................................641 Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence ...........644 Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence ...............................................................647 Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Se- quence .......................................................................................................................................................................650 Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence ...............................................................653 Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence 656 Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence ....................................................659 Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence.........662 Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence ....................................................665 Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence.........668 Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence.........................................................671 Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence.........................................................674 Table 8.105 Steps for a Sink getting Source Battery status Sequence ....................................................................677 Table 8.106 Steps for a Source getting Sink Battery status Sequence ....................................................................680 Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence .............................683 Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence .............................686 Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence.......................689 Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence.......................692 Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence ...............695 Table 8.112 Steps for a Source getting Country Codes Sequence.............................................................................698 Table 8.113 Steps for a Source getting Sink's Country Codes Sequence................................................................701 Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence..................................................704 Table 8.115 Steps for a Source getting Country Information Sequence ................................................................707 Table 8.116 Steps for a Source getting Sink's Country Information Sequence...................................................710 Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence.....................................713 Table 8.118 Steps for a Source getting Revision Information Sequence ...............................................................716 Table 8.119 Steps for a Source getting Sink's Revision Information Sequence..................................................719 Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence....................................722 Table 8.121 Steps for a Sink getting Source Information Sequence ........................................................................725 Page 32 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence .728 Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence...................................731 Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence...................................734 Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence........737 Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence.................740 Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence.................743 Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Se- quence .......................................................................................................................................................................746 Table 8.129 Steps for Initiator to UFP Discover Identity (ACK)................................................................................749 Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) ...............................................................................752 Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY)..............................................................................755 Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK).............................................................................................758 Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) ............................................................................................761 Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) ..........................................................................................764 Table 8.135 Steps for DFP to UFP Discover Modes (ACK) ...........................................................................................767 Table 8.136 Steps for DFP to UFP Discover Modes (NAK)...........................................................................................770 Table 8.137 Steps for DFP to UFP Discover Modes (BUSY).........................................................................................773 Table 8.138 Steps for DFP to UFP Enter Mode..................................................................................................................776 Table 8.139 Steps for DFP to UFP Exit Mode .....................................................................................................................779 Table 8.140 Steps for DFP to Cable Plug Enter Mode.....................................................................................................782 Table 8.141 Steps for DFP to Cable Plug Exit Mode........................................................................................................785 Table 8.142 Steps for Initiator to Responder Attention................................................................................................788 Table 8.143 Steps for BIST Carrier Mode Test..................................................................................................................790 Table 8.144 Steps for BIST Test Data Test..........................................................................................................................793 Table 8.145 Steps for BIST Shared Capacity Test Mode Test .....................................................................................796 Table 8.146 Steps for UFP USB4 Mode Entry (Accept)..................................................................................................799 Table 8.147 Steps for UFP USB4 Mode Entry (Reject)...................................................................................................802 Table 8.148 Steps for UFP USB4 Mode Entry (Wait)......................................................................................................805 Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) ....................................................................................808 Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject)......................................................................................811 Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait).........................................................................................814 Table 8.152 Steps for Unstructured VDM Message Sequence....................................................................................817 Table 8.153 Steps for VDEM Message Sequence ..............................................................................................................820 Table 8.154 Policy Engine States.............................................................................................................................................966 9 States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975 Table 9.1 USB Power Delivery Type Codes ...................................................................................................................985 Table 9.2 USB Power Delivery Capability Descriptor...............................................................................................986 Table 9.3 Battery Info Capability Descriptor................................................................................................................987 Table 9.4 PD Consumer Port Descriptor.........................................................................................................................988 Table 9.5 PD Provider Port Descriptor............................................................................................................................989 Table 9.6 PD Requests ............................................................................................................................................................990 Table 9.7 PD Request Codes.................................................................................................................................................990 Table 9.8 PD Feature Selectors...........................................................................................................................................990 Table 9.9 Get Battery Status Request...............................................................................................................................991 Table 9.10 Battery Status Structure....................................................................................................................................991 Table 9.11 Set PD Feature........................................................................................................................................................992 Table 9.12 Battery Wake Mask..............................................................................................................................................993 Table 9.13 Charging Policy Encoding .................................................................................................................................994 10 Power Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 995 Table 10.1 Considerations for Sources ..............................................................................................................................996 Table 10.2 SPR Normative Voltages and Minimum Currents ..................................................................................997 Table 10.3 SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP.................998 Table 10.4 SPR Source Port Present PDP less than Port Maximum PDP Examples.......................................999 Table 10.5 Fixed Supply PDO - Source 5V......................................................................................................................1001 Table 10.6 Fixed Supply PDO - Source 9V......................................................................................................................1002 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 33 Table 10.7 Fixed Supply PDO - Source 15V...................................................................................................................1002 Table 10.8 Fixed Supply PDO - Source 20V...................................................................................................................1002 Table 10.9 SPR Adjustable Voltage Supply (AVS) Voltage Ranges......................................................................1004 Table 10.10 SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP...1005 Table 10.11 SPR Programmable Power Supply Voltage Ranges............................................................................1006 Table 10.12 EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable 1009 Table 10.14 EPR Source Examples when Port Present PDP is less than Port Maximum PDP...................1010 Table 10.13 EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable.......................................................................................................................................1010 Table 10.15 EPR Adjustable Voltage Supply (AVS) Voltage Ranges.....................................................................1012 A CRC calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1015 B Message Sequence Examples (Deprecated) . . . . . . . . . . . . . . . . . . . . . . . 1016 C VDM Command Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1017 Table C.1 Discover Identity Command request from Initiator Example .......................................................1017 Table C.2 Discover Identity Command response from Active Cable Responder Example ....................1018 Table C.3 Discover Identity Command response from Hub Responder Example .....................................1020 Table C.4 Discover SVIDs Command request from Initiator Example............................................................1021 Table C.5 Discover SVIDs Command response from Responder Example ...................................................1022 Table C.6 Discover Modes Command request from Initiator Example ..........................................................1023 Table C.7 Discover Modes Command response from Responder Example..................................................1024 Table C.8 Enter Mode Command request from Initiator Example...................................................................1025 Table C.9 Enter Mode Command response from Responder Example...........................................................1026 Table C.10 Enter Mode Command request with additional VDO Example .....................................................1027 Table C.11 Exit Mode Command request from Initiator Example ......................................................................1028 Table C.12 Exit Mode Command response from Responder Example..............................................................1029 Table C.13 Attention Command request from Initiator Example........................................................................1030 Table C.14 Attention Command request from Initiator with additional VDO Example ............................1031 D BMC Receiver Design Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1032 E FRS System Level Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1038 Table E.1 Sequence for setup of a Fast Role Swap (Hub connected to Power Adapter first)...............1041 Table E.2 Sequence for setup of a Fast Role Swap (Hub connected to laptop before Power Adapter) 1042 Table E.3 Sequence for slow VBUS discharge (it discharges after FR_Swap message is sent)..............1045 Table E.4 VBUS discharges quickly after adapter disconnected.........................................................................1046 Page 34 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1 Introduction USB has evolved from a data interface capable of supplying limited power to a primary provider of power with a data interface. Today many devices charge or get their power from USB Ports contained in laptops, cars, aircraft or even wall sockets. USB has become a ubiquitous power socket for many small devices such as cell phones and other hand-held devices. Users need USB to fulfill their requirements not only in terms of data but also to provide power to, or charge, their devices simply, often without the need to load a driver, in order to carry out “traditional” USB functions. There are, however, still many devices which either require an additional power connection to the wall, or exceed the USB default current in order to operate. Increasingly, international regulations require better energy management due to ecological and practical concerns relating to the availability of power. Regulations limit the amount of power available from the wall which has led to a pressing need to optimize power usage. The USB Power Delivery Specification has the potential to minimize waste as it becomes a standard for charging devices that are not satisfied by [USBBC 1.2] or [USB Type-C 2.4]. Wider usage of wireless solutions is an attempt to remove data cabling but the need for “tethered” charging remains. In addition, industrial design requirements drive wired connectivity to do much more over the same connector. USB Power Delivery is designed to enable the maximum functionality of USB by providing more flexible power delivery along with data over a single cable. Its aim is to operate with and build on the existing USB ecosystem; increasing power levels from existing USB standards, for example [USBBC 1.2], enabling new higher power use cases such as USB powered Hard Disk Drives (HDDs), laptops and monitors. With USB Power Delivery the power direction is no longer fixed. This enables the product with the power (USB Host or Peripheral) to provide the power. For example, a display with a supply from the wall can power, or charge, a laptop. Alternatively, USB Chargers are able to supply power to laptops and other Battery powered devices through their, traditional power providing, USB Ports. USB Power Delivery enables Hubs (including Hubs embedded in other devices such as docks or monitors) to become the means to optimize power management across multiple peripherals by allowing each device to take only the power it requires, and to get more power when required for a given application. Optionally the Hubs can communicate with the PC to enable even more intelligent and flexible management of power either automatically or with some level of user intervention. USB Power Delivery allows low power cases such as headsets to Negotiate for only the power they require. This provides a simple solution that enables USB devices to operate at their optimal power levels. The Power Delivery Specification, in addition to providing mechanisms to Negotiate power also can be used as a side-band channel for standard and vendor defined messaging. The specification enables discovery of cable Capabilities such as supported speeds and current levels. Power Delivery enables alternative modes of operation by providing the mechanisms to discover, enter and exit Modes such as EPR Mode, USB4® Mode or Alternate Modes. 1.1 Overview This specification defines how USB Devices can Negotiate for more current and/or higher or lower voltages over the USB cable (using the USB Type-C® CC wire as the communications channel) than are defined in the [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] specifications. It allows Devices with greater power requirements than can be met with today's specification to get the power they require to operate from VBUS and Negotiate with external power sources (e.g., Chargers). In addition, it allows a Source and Sink to swap Power Roles such that a USB Device could supply power to the USB Host. For example, a display could supply power to a laptop to operate or charge its Battery. This specification also adds a mechanism to swap the Data Roles such that the upstream facing Port becomes the downstream facing Port and vice versa. It also enables a swap of the end supplying VCONN to a powered cable. The USB Power Delivery Specification is guided by the following principles:  Works seamlessly with legacy USB Devices. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 35  Compatible with existing spec-compliant USB cables.  Minimizes potential damage from non-compliant cables (e.g., ‘Y’ cables etc.).  Optimized for low-cost implementations. This specification defines mechanisms to discover, enter and exit Alternate Modes defined either by a standard or by a particular vendor. These Alternate Modes can be supported either by the Port Partner or by a cable connecting the two Port Partners. The specification defines mechanisms to discover the Capabilities of cables which can communicate using Power Delivery. To facilitate optimum charging, the specification defines two mechanisms a USB Charger can Advertise for the device to use: 1) A list of Fixed Supply voltages each with a maximum current. The device selects a voltage and current from the list. This is the traditional model used by devices that use internal electronics to manage the charging of their Battery including modifying the voltage and current actually supplied to the Battery. The side-effect of this model is that the charging circuitry generates heat that can be problematic for small form factor devices. 2) A list of programmable voltage ranges, in SPR PPS Mode, each with a maximum current. The device re- quests a voltage (in 20mV increments) that is within the Advertised range and a maximum current. The USB PPS Charger delivers the requested voltage until the maximum current is reached at which time the USB PPS Charger reduces its output voltage so as not to supply more than the requested maximum current. During the high current portion of the charge cycle, the USB PPS Charger can be directly con- nected (through an appropriate safety device) to the Battery. This model is used by devices that want to minimize the thermal impact of their internal charging circuitry. 3) A list of adjustable voltage ranges, in SPR AVS Mode or EPR AVS Mode, each with a maximum current. The device requests a voltage (in 100mV increments) that is within the Advertised range and a maxi- mum current. The USB AVS Charger delivers the requested voltage. 1.2 Purpose The USB Power Delivery specification defines a power delivery system covering all elements of a USB system including USB Hosts, USB Devices, Hubs, Chargers and cable assemblies. This specification describes the architecture, protocols, power supply behavior, connectors and cabling necessary for managing power delivery over USB at up to 100W in SPR Mode and 240W in EPR Mode. This specification is intended to be fully compatible with and extend the existing USB infrastructure. It is intended that this specification will allow system OEMs, power supply and Peripheral developers adequate flexibility for product versatility and market differentiation without losing backwards compatibility. USB Power Delivery is designed to operate independently of the existing USB bus defined mechanisms used to Negotiate power which are:  [USB 2.0], [USB 3.2] in band requests for high power interfaces.  [USBBC 1.2] mechanisms for supplying higher power (not mandated by this specification).  [USB Type-C 2.4] mechanisms for supplying higher power. Initial operating conditions remain the USB Default Operation as defined in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2].  The DFP sources vSafe5V over VBUS.  The UFP consumes power from VBUS. Page 36 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.2.1 Scope This specification is intended as an extension to the existing [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2] specifications. It addresses only the elements required to implement USB Power Delivery. It is targeted at power supply vendors, manufacturers of [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2] platforms, devices and cable assemblies. Normative information is provided to allow interoperability of components designed to this specification. Informative information, when provided, illustrates possible design implementation. 1.3 Section Overview This specification contains the following sections: Table 1.1 Section Overview Section Description Section 1, "Introduction" Introduction, conventions used in the document, list of terms and abbreviations, references, and details of parameter usage. Section 2, "Overview" Overview of the document including a description of the operation of PD and the architecture. Section 3, "USB Type-A and USB Type- B Cable Assemblies and Connectors" Mechanical and electrical characteristics of the cables and connectors used by PD. Section Deprecated. See [USBPD 2.0] for legacy PD connector specification. Section 4, "Electrical Requirements" Electrical requirements for Dead Battery operation and cable detection. Section 5, "Physical Layer" Details of the PD PHY Layer requirements Section 6, "Protocol Layer" Protocol Layer requirements including the Messages, timers, counters, and state operation. Section 7, "Power Supply" Power supply requirements for both Providers and Consumers. Section 8, "Device Policy" Device Policy Manager requirements. Policy Engine Atomic Message Sequence (AMS) diagrams and state diagrams Section 9, "States and Status Reporting" PDUSB Device requirements including mapping of VBUS to USB states. System Policy Manager requirements including descriptors, events, and requests. Section 10, "Power Rules" PDP Rating definitions for PD. Section A, "CRC calculation" Example CRC calculations. Section B, "Message Sequence Examples (Deprecated)" Scenarios illustrating Device Policy Manager operation. Deprecated Section C, "VDM Command Examples" Examples of Structured VDM usage.Section Deprecated. Section D, "BMC Receiver Design Examples" BMC Receiver Design Examples. Section E, "FRS System Level Example" FRS System Level Example. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 37 1.4 Conventions 1.4.1 Precedence If there is a conflict between text, figures, and tables, the precedence Shall be tables, figures, and then text. In there is a conflict between a generic statement and a more specific statement, the more specific statement Shall apply. 1.4.2 Keywords The following keywords differentiate between the levels of requirements and options. Table 1.2 Keywords Keyword Definition Conditional Normative Conditional Normative is a keyword used to indicate a feature that is mandatory when another related feature has been implemented. Designers are mandated to implement all such requirements, when the dependent features have been implemented, to ensure interoperability with other compliant devices. Deprecated Deprecated is a keyword used to indicate a feature, supported in previous releases of the specification, which is no longer supported. Discard See Discarded. Discarded Discard, Discards and Discarded are equivalent keywords indicating that a Packet when received Shall be thrown away by the PHY Layer and not passed to the Protocol Layer for processing. No GoodCRC Message Shall be sent in response to the Packet. Discards See Discarded. Ignore See Ignored. Ignored Ignore, Ignores and Ignored are equivalent keywords indicating Messages or Message fields which, when received, Shall result in no special action by the receiver. An Ignored Message Shall only result in returning a GoodCRC Message to acknowledge Message receipt. A Message with an Ignored field Shall be processed normally except for any actions relating to the Ignored field. Ignores See Ignored. Informative Informative is a keyword indicating text with no specific requirements, provided only to improve understanding. Invalid Invalid is a keyword when used in relation to a Packet indicates that the Packet’s usage or fields fall outside of the defined specification usage. When Invalid is used in relation to an Explicit Contract it indicates that a previously established Explicit Contract which can no longer be maintained by the Source. When Invalid is used in relation to individual K-codes or K-code sequences indicates that the received Signaling falls outside of the defined specification. May May is a keyword that indicates a choice with no implied preference. May Not May Not is a keyword that is the inverse of May. Indicates a choice to not implement a given feature with no implied preference. N/A N/A is a keyword that indicates that a field or value is not applicable and has no defined value and Shall Not be checked or used by the recipient. Normative See Shall. Optional Optional, Optionally and Optional Normative are equivalent keywords that describe features not mandated by this specification. However, if an Optional feature is implemented, the feature Shall be implemented as defined by this specification. Optional Normative See Optional. Optionally See Optional. Page 38 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.4.3 Numbering Numbers that are immediately followed by a lowercase “b” (e.g., 01b) are binary values. Numbers that are immediately followed by an uppercase “B” are byte values. Numbers that are immediately followed by a lowercase “h” (e.g., 3Ah) or are preceded by “0x” (e.g., 0xFF00) are hexadecimal values. Numbers not immediately followed by either a “b”, “B”, or “h” are decimal values. Reserved Reserved is a keyword indicating bits, bytes, words, fields, and code values that are set-aside for future standardization. Their use and interpretation May be specified by future extensions to this specification and Shall Not be utilized or adapted by vendor implementation. A Reserved bit, byte, word, or field Shall be set to zero by the sender and Shall be Ignored by the receiver. Reserved field values Shall Not be sent by the sender and Shall be Ignored by the receiver. Shall Shall and Normative are equivalent keywords indicating a mandatory requirement. Designers are mandated to implement all such requirements to ensure interoperability with other compliant devices. Shall Not Shall Not is a keyword that is the inverse of Shall indicating non-compliant operation. Should Should is a keyword indicating flexibility of choice with a preferred alternative; equivalent to the phrase “it is recommended that…”. Should Not Should Not is a keyword is the inverse of Should; equivalent to the phrase “it is recommended that implementations do not…”. Static Static is a keyword indicating that a field that never changes. Valid Valid is a keyword that is the inverse of Invalid indicating either a Packet or Signaling that fall within the defined specification or an Explicit Contract that can be maintained by the Source. Table 1.2 Keywords (Continued) Keyword Definition Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 39 1.5 Related Documents Document references listed in Table 1.3, "Document References" are inclusive of all approved and published ECNs and Errata. Table 1.3 Document References Bookmark Reference Title [DPTC2.1] DisplayPortTM Alt Mode on USB Type-C Standard www.vesa.org. [IEC 60950-1] IEC 60950-1:2005 Information technology equipment – Safety – Part 1: General requirements: Amendment 1:2009, Amendment 2:2013. www.iec.ch. [IEC 60958-1] IEC 60958-1:2021 Digital Audio Interface Part:1 General. www.iec.ch. [IEC 62368-1] IEC 62368-1:2018 Audio/Video, information, and communication technology equipment – Part 1: Safety requirements. www.iec.ch. [IEC 62368-3] IEC 62368-3:2017 Audio/video, information, and communication technology equipment - Part 3: Safety aspects for DC power transfer through communication cables and ports www.iec.ch. [IEC 63002] IEC 63002:2021 Interoperability specifications and communication method for external power supplies used with computing and consumer electronics devices www.iec.ch. [ISO 3166] ISO 3166 international Standard for country codes and codes for their subdivisions. http://www.iso.org/iso/home/standards/country_codes.htm. [TBT3] see [USB4] Chapter 13 for ThunderboltTM 3 device operation. [UCSI] USB Type-C Connector System Software Interface (UCSI) Specification https:// www.usb.org/documents. [USB 2.0] Universal Serial Bus 2.0 Specification, https://www.usb.org/documents. [USB 3.2] Universal Serial Bus 3.2 Specification https://www.usb.org/documents. [USB Type-C 2.4] Universal Serial Bus Type-C Cable and Connector Specification, https://www.usb.org/ documents. [USB4] Universal Serial Bus 4 Specification (USB4®), https://www.usb.org/documents. [USBBC 1.2] Universal Serial Bus Battery Charging Specification plus Errata (referred to in this document as the Battery Charging specification). https://www.usb.org/documents. [USBPD 2.0] Universal Serial Bus Power Delivery Specification, https://www.usb.org/documents. [USBPDCompliance] USB Power Delivery Compliance Test Specification, https://www.usb.org/documents. [USBPDFirmwareUpdate 1.0] Universal Serial Bus Power Delivery Firmware Update Specification, https:// www.usb.org/documents. [USBTypeCAuthentication 1.0] Universal Serial Bus Type-C Authentication Specification, https://www.usb.org/ documents. [USBTypeCBridge 1.1] Universal Serial Bus Type-C Bridge Specification, https://www.usb.org/documents. Page 40 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.6 Terms and Abbreviations This section defines terms used throughout this document. For additional terms that pertain to the Universal Serial Bus, see Chapter 2, “Terms and Abbreviations,” in [USB 2.0], [USB 3.2], [USB Type-C 2.4] and [USBBC 1.2]. Table 1.4 Terms and Abbreviations Term Description (A)PDO Refers to both the PDO and APDO collectively. AC Supply AC Supplied Refers to the main AC power source typically provided to the wall AKA “mains”. Active Cable A cable with a USB Type-C plug on each end that incorporates data bus signal conditioning circuits. The cable supports the Structured VDM Discover Identity Command to expose its characteristics in addition to other Structured VDM Commands (Electronically Marked Cable see [USB Type-C 2.4]). Active Cable VDO VDO defining the Capabilities of an Active Cable. Active Mode A Mode which has been through the Mode Entry process but not the Mode Exit process. Adjustable Voltage Supply A power supply whose output voltage can be adjusted to an operating voltage within its Advertised range. These Capabilities are exposed by the Adjustable Voltage Supply (AVS) APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). Note: Unlike the SPR PPS, the SPR AVS and EPR AVS do not support current limit. Advertise An offer made by a Source in the Source_Capabilities/EPR_Source_Capabilities Message (e.g., an APDO or PDO). Alternate Mode Operation defined by a Vendor or Standard’s organization, which is associated with a SVID. The definition of Alternate Modes is outside the scope of USB-IF specifications. Entry to and exit from the Alternate Mode uses the Mode Entry and Mode Exit processes. As defined in [USB Type-C 2.4]. Alternate Mode Adapter A PDUSB Device which supports Alternate Modes as defined in [USB Type-C 2.4]. Note: Since an AMA is a PDUSB Device, it has a single UFP that is only addressable by SOP Packets. Alternate Mode Controller A DFP that supports connection to AMAs as defined in [USB Type-C 2.4]. A DFP that is an AMC can also be a PDUSB Host. AMA See Alternate Mode Adapter. AMC See Alternate Mode Controller. AMS See Atomic Message Sequence. APDO See Augmented Power Data Object. Assured Capacity Charger As defined in [USB Type-C 2.4]. This maps to a Charger with one or more Guaranteed Capability Ports. Assured Capacity Group As defined in [USB Type-C 2.4]. This maps to a group of Guaranteed Capability Ports. Atomic Message Sequence A fixed sequence of Messages as defined in Section 8.3.2, "Atomic Message Sequence Diagrams" typically starting and ending in one of the following states: PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready. An AMS is Non-interruptible. Attach Mechanical joining of the Port Pair by a cable. Attached USB Power Delivery Ports which are mechanically joined with USB cable. Attachment See Attach. Augmented Power Data Object Data Object used to expose a Source Port's or Sink Port's power Capabilities as part of a Source_Capabilities/EPR_Source_Capabilities or Sink_Capabilities/EPR_Sink_Capabilities Message respectively. An SPR PPS Data Object, SPR AVS Data Object and EPR AVS Data Object are defined. AVS See Adjustable Voltage Supply. AVS Mode A power supply, currently operating as an AVS, is said to be operating in AVS Mode. Battery A power storage device residing behind a Port that can either be a Source or Sink of power. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 41 Battery Slot A physical location where a Hot Swappable Battery can be installed. A Battery Slot might or might not have a Hot Swappable Battery present in a Battery Slot at any given time. Battery Supply A power supply that directly applies the output of a Battery to VBUS. This is exposed by the Battery Supply PDO (see Section 6.4.1.2.3, "Battery Supply Power Data Object"). BDO See BIST Data Object. BFSK See Binary Frequency Shift Keying. Bi-phase Mark Coding Modification of Manchester coding where each zero has one transition and a one has two transitions (see [IEC 60958-1]). Binary Frequency Shift Keying A Signaling Scheme now Deprecated in this specification. BFSK used a pair of discrete frequencies to transmit binary (0s and 1s) information over VBUS. See [USBPD 2.0] for further details. BIST Built-In Self-Test - Power Delivery testing mechanism for the PHY Layer. BIST Data Object Data Object used by BIST Messages. BIST Mode A BIST receiver or transmitter test mode enabled by a BIST Message. BIST Carrier Mode A BIST Mode in which the PHY Layer sends out a BMC encoded continuous string of alternating "1"s and "0"s. BIST Test Data Mode A BIST Mode in which the PHY Layer sends out a GoodCRC Message and then enters a test mode where it sends no further Messages, except GoodCRC Messages, in response to received Messages. BIST Shared Capacity Test Mode A BIST Mode applicable only to a Shared Capacity Group of Ports where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. BMC See Bi-phase Mark Coding. Cable Capabilities Capabilities offered by a Cable Plug. Cable Discovered USB Power Delivery Ports that have exchanged a Message and a GoodCRC Message response with a Cable Plug or a VPD using the USB Power Delivery protocol so that both the Port and the Cable Plug know that each is PD Capable and which Revision they each support. Cable Discovery See Cable Discovered. Cable Plug Term used to describe a PD Capable element in a Multi-Drop system addressed by SOP’ Packets/ SOP’’ Packets. Logically the Cable Plug is associated with a USB Type-C plug at one end of the cable. In a practical implementation, the electronics might reside anywhere in the cable. Cable Reset This is initiated by Cable Reset Signaling from the DFP. It restores the Cable Plugs to their default, power up condition and resets the PD communications engine in the cable to its default state. It does not reset the Port Partners but does restore VCONN to its Attachment state. Cable VDO VDO returned by the Cable Plug containing Cable Capabilities. Capabilities Features supported by a product. These can include, for example, power levels supplied/ needed, cable type, Battery support or [USB4] support. Capabilities Mismatch Indication from the Sink that the Source’s Advertised Capabilities don’t match the Sink’s needs. CC See Configuration Channel. Cert Stat VDO The Cert Stat VDO contains the XID assigned by USB-IF to the product before certification in binary format. Charge Through A mechanism for a VCONN Powered USB Device (VPD) to pass power and CC communication from one Port to the other without any interference or re-regulation. Charge Through Port The USB Type-C receptacle on a USB Device that is designed to allow a Source to be connected through the USB Device to charge a system to which it is Attached. Most common use is to allow a single Port USB Host to support a USB Device while being charged. Charger Provider whose primary purpose is to supply power to a Consumer or Consumers in order to charge their Battery. Chunk A MaxExtendedMsgChunkLen (26 byte) or less portion of a Data Block. Data Blocks can be sent either as a single Message or as a series of Chunks. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 42 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Chunked See Chunking. Chunked Extended Message Extended Message which has been broken up into Chunks. Chunking The process of breaking up a Data Block larger than MaxExtendedMsgLegacyLen (26-bytes) into two or more Chunks. Chunking Layer Part of the Protocol Layer responsible for Chunking. CL See Current Limit. Cold Socket A Port that does not apply vSafe5V on VBUS until a Sink is Attached. Collision Avoidance Mechanisms to prevent simultaneous communication by the Source, Sink and Cable Plug on CC. Command Request and response pair defined as part of a Structured Vendor Defined Message (see Section 6.4.4.2, "Structured VDM"). Configuration Channel Single wire used by the BMC PHY Layer Signaling Scheme (see [USB Type-C 2.4]). Connect See Connected. Connected USB Power Delivery ports that have exchanged a Message and a GoodCRC Message response using the USB Power Delivery protocol so that both Port Partners know that each is PD Capable. Constant Voltage A constant voltage feature of an SPR PPS Source. The SPR PPS Source output voltage remains constant as the load changes up to its Current Limit. Consumer The capability of a PD Port (typically a Device's UFP) to sink power from the power conductor (e.g., VBUS). This corresponds to a USB Type-C Port with Rd asserted on its CC wire. Consumer/Provider A Consumer with the additional capability to function as a Provider. This corresponds to a Dual- Role Power Port with Rd asserted on its CC wire. Continuous BIST Mode The BIST Mode where the Port or Cable Plug being tested sends a continuous stream of test data. Contract An agreement on both power level and direction is reached between a Port Pair. A Contract could be explicitly Negotiated between the Port Pair or could be an implicit power level defined by the current State. While operating in Power Delivery mode there will always be either an Explicit Contract or Implicit Contract in place. The Contract can only be altered in the case of a Negotiation/Re-negotiation, Power Role Swap, Fast Role Swap, Hard Reset, Error Recovery or failure of the Source. Control Message A Control Message is defined as a Message with the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. CRC CRC stands for Cyclic Redundancy Check. It is an error-detecting code used to determine if a block of data has been corrupted. CT-VPD See VCONN Powered USB Charge Through Device. Current Limit A current limiting feature of an SPR PPS Source. When a Sink operating in SPR PPS mode attempts to draw more current from the Source than the requested Current Limit value, the Source reduces its output voltage so the current it supplies remains at or below the requested value. Note: Current Limit is not supported by SPR AVS and EPR AVS Sources. CV See Constant Voltage. Data Block An Extended Message Payload data unit. The size of each type of Data Block is specified as a series of bytes up to MaxExtendedMsgLen bytes in length. This is distinct from a Data Object used by a Data Message which is always a 32-bit object. Data Message A Data Message consists of a Message Header followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is always a non-zero value. Data Object A Data Message Payload data unit. This 32-bit object contains information specific to different types of Data Message. For example Power, Request, BIST, and Vendor Data Objects are defined. Data Reset Process which resets USB Communication. Data Role A Port Partner will be in one of two Data Roles; either DFP (USB Host) or UFP (USB Device). Data Role Swap Process of exchanging the Data Roles between Port Partners. Dead Battery A device has a Dead Battery when the Battery in a device is unable to power its functions. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 43 Default Contract An agreement on current at 5V is reached between a Port Pair based on USB Type-C current ([USB Type-C 2.4]). Detach Mechanical unjoining of the Port Pair by removal of the cable. Detached USB Power Delivery Ports which are no longer mechanically joined with USB cable. Detaches See Detach. Device When lower cased (device), it refers to any USB product, either USB Device or USB Host. When in upper case refers to a USB Device (Peripheral or Hub). Device Policy Policy applied across multiple Ports in a Source or Sink. Device Policy Manager Module running in a Source or Sink that applies Device Policy to each Port in the device, as Local Policy, via the Policy Engine. DFP See Downstream Facing Port. DFP VDO VDO returned by the DFP containing Capabilities. Differential Non-Linearity The difference between an ideal LSB step, and the real observable LSB step when the Power Source is operating in either PPS or AVS mode. A DNL of 0 indicates that the step is ideal. If DNL is positive the step is larger than the ideal LSB, and if it is negative then the step is smaller than ideal. Discovery Process Command sequence using Structured Vendor Defined Messages resulting in identification of the Port Partner and Cable Plug, and their supported SVIDs and Alternate Modes. DNL See Differential Non-Linearity. Downstream Facing Port Indicates the Port's position in the USB topology which typically corresponds to a USB Host root Port or Hub downstream Port as defined in [USB Type-C 2.4]. At connection, the Port defaults to operation as the Source and as a USB Host (when USB Communication is supported). DPM See Device Policy Manager. DRD See Dual-Role Data. DRP See Dual-Role Power. Dual-Role Data Capability of operating as either a DFP or UFP. Dual-Role Data Port A Port capable of operating as DRD. Dual-Role Power Capability of operating as either a Source or Sink. Dual-Role Power Device A product containing one or more Dual-Role Power Ports that can operate as either a Source or a Sink. Dual-Role Power Port A Port capable of operating as a DRP. EM See Extended Message. End of Packet K-code marker used to delineate the end of a Packet. EOP See End of Packet. EPR See Extended Power Range. EPR AVS A power supply operating in EPR Mode whose output voltage can be adjusted to an operating voltage within its Advertised range. Unlike SPR PPS it does not support current limit. The AVS Capabilities are exposed by the Adjustable Voltage Supply APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). EPR AVS Mode A EPR Source, currently operating in an EPR AVS Contract, is said to be operating in EPR AVS Mode. EPR Cable A cable which is rated to operate in both SPR Mode and EPR Mode. EPR Capabilities The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. EPR Capable A product which has the ability to operate in EPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 44 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 EPR Mode A Power Delivery mode of operation where maximum allowable voltage is 48V. The Sink complies to the requirements of [IEC 62368-1] for operation with a PS3 Source. The Source complies to the requirements of [IEC 62368-1] for operation with a PS3 Sink. The cable complies with [IEC 62368-1]. Entry into the EPR Mode requires that an EPR Source is Attached to an EPR Sink with an EPR Cable. The EPR Source will only enter the EPR Mode when requested to do so by the Sink and it has determined it is Attached to an EPR Sink with an EPR Capable cable. Only the EPR_Source_Capabilities and the EPR_Request Messages are allowed to Negotiate EPR Explicit Contracts. The SPR Mode Messages (Source_Capabilities and Request) are not allowed to be used while in EPR Mode. EPR (A)PDO Fixed Supply PDO that offers either 28V, 36V or 48V. Adjustable Voltage Supply (AVS) APDO whose Maximum voltage is the highest Fixed Supply PDO voltage in the EPR_Source_Capabilities Message and no more than 240W. EPR Sink A Sink that supports both SPR Mode and EPR Mode. EPR Sink Port A Port exposed on an EPR Sink. EPR Source A Source that supports both SPR Mode and EPR Mode. EPR Source Port A Port exposed on an EPR Source. Error Recovery Port enters the ErrorRecovery State as defined in [USB Type-C 2.4]. Explicit Contract An agreement reached between a Port Pair as a result of the Power Delivery Negotiation process. An Explicit Contract is established (or continued) when a Source sends an Accept Message in response to a Request Message sent by a Sink followed by a PS_RDY Message sent by the Source to indicate that the power supply is ready. This corresponds to the PE_SRC_Ready State for a Source Policy Engine and the PE_SNK_Ready State for a Source Policy Engine. The Explicit Contract can be altered through the Re-negotiation process. Extended Capabilities An Extended Message containing Capabilities information. Extended Control Message An Extended Message containing control information only. Extended Message A Message containing Data Blocks. The Extended Message is defined by the Extended field in the Message Header being set to one and contains an Extended Message Header immediately following the Message Header. Extended Message Header Every Extended Message contains a 16-bit Extended Message Header immediately following the Message Header containing information about the Data Block and any Chunking being applied. Extended Power Range Extends the power range from a maximum of 100W (SPR) to a maximum of 240W (EPR). When operating in the EPR Mode, only EPR specific Messages (the EPR_Source_Capabilities Message and the EPR_Request Message) are used to Negotiate Explicit Contracts. External Supply Power supply external to the device. This could be powered from the wall or from any other power source. Fast Role Swap Process of exchanging the Source and Sink Power Roles between Port Partners rapidly due to the disconnection of an external power supply. Fast Role Swap Request An indication from an Initial Source to the Initial Sink that a Fast Role Swap is needed. The Fast Role Swap Request is indicated by driving the CC line to ground for a short period; it is not a Message or Signaling. First Explicit Contract The Explicit Contract that immediately follows an Attach, power on Hard Reset, Power Role Swap or Fast Role Swap event. Fixed Battery Fixed Batteries A Battery that is not easily removed or replaced by an end user e.g., requires a special tool to access or is soldered in. Fixed Supply A well-regulated fixed voltage power supply. This is exposed by the Fixed Supply PDO (see Section 6.4.1.2.1, "Fixed Supply Power Data Object") Frame Generic term referring to an atomic communication transmitted by PD such as a Packet, Test Frame or Signaling. FRS See Fast Role Swap. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 45 Guaranteed Capability Port A Guaranteed Capability Port is always capable of delivering its Port Maximum PDP and indicates this by setting its Port Present PDP to be the same as its Port Maximum PDP except when limited by the cable’s Capabilities. This is a Static capability. Hard Reset This is initiated by Hard Reset Signaling from either Port Partner. It restores VBUS to USB Default Operation and resets the PD communications engine to its default State in both Port Partners as well as in any Attached Cable Plugs. It restores both Port Partners to their default Data Roles and returns the VCONN Source to the Source Port. A DRP Source Port operating as a Source will continue to operate as a Source. Host See USB Host. Hot Swappable Battery A Battery that is easily accessible for a user to remove or change for another Battery. Hub A USB Device that provides additional connections to the USB. ID Header VDO The VDO in a Discover Identity Command immediately following the VDM Header. The ID Header VDO contains information corresponding to the Power Delivery Product. Idle Condition on CC where there are no signal transitions within a given time window. See Section 5.8.6.1, "Definition of Idle". Implicit Contract An agreement on power levels between a Port Pair which occurs, not because of the Power Delivery Negotiation process, but because of a Power Role Swap or Fast Role Swap. Implicit Contracts are transitory since the Port Pair is required to immediately Negotiate an Explicit Contract after the Power Role Swap. An Implicit Contract Shall be limited to USB Type-C current (see [USB Type-C 2.4]). Initial Sink Sink at the start of a Power Role Swap or Fast Role Swap which transitions to being the New Source. Initial Source Source at the start of a Power Role Swap or Fast Role Swap which transitions to being the New Sink. Initiator The initial sender of a Command request in the form of a query. Invariant PDOs A Source Port that offers Invariant PDOs will always Advertise the same PDOs except when limited by the cable. IoC The Negotiated current value as defined in [IEC 63002]. IR Drop The voltage drop across the cable and connectors between the Source and the Sink as defined in [USB Type-C 2.4]. It is a function of the resistance of the ground and power wire in the cable plus the contact resistance in the connectors times the current flowing over the path. K-code Special symbols provided by the 4b5b coding scheme. K-codes are used to signal Hard Reset and Cable Reset and delineate Packet boundaries. Local Policy Every PD Capable device has its own Policy, called the Local Policy that is executed by its Policy Engine to control its power delivery behavior. The Local Policy at any given time might be the default policy, hard coded or modified by changes in operating parameters or one provided by the system USB Host or some combination of these. The Local Policy Optionally can be changed by a System Policy Manager. LPS Limited Power Supply as defined in [IEC 62368-1]. LSB An abbreviation for Least Significant Bit. Managed Capability Port A Managed Capability Port can have its Port Present PDP set to a different value than its Port Maximum PDP. Its Port Present PDP value can be dynamic and change during normal operation. Message The Packet Payload consisting of a Message Header for Control Messages and a Message Header and data for Data Messages and Extended Messages as defined in Section 6.2, "Messages". Message Header Every Message starts with a 16-bit Message Header containing basic information about the Message and the PD Port’s Capabilities. Messaging Communication in the form of Messages as defined in Section 6, "Protocol Layer". Modal Operation Operation where there are one or more Active Modes. Modal Operation ends when there are no longer any Active Modes. Mode Mode is a general term used to describe a particular type of operation of a given device. Examples of modes are: Alternate Mode, EPR Mode, SPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 46 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Mode Entry Process to start operation in a particular Mode. Mode Exit Process to end operation in a particular Mode. Multi-Drop PD is a Multi-Drop system sharing the Power Delivery communication channel between the Port Partners and the cable. Negotiate See Negotiation. Negotiated See Negotiation. Negotiation This is the PD process whereby: 1) The Source Advertises its Capabilities. 2) The Sink requests one of the Advertised Capabilities. 3) The Source acknowledges the request, alters its output to satisfy the request and informs the Sink. The result of the Negotiation is a Contract for power delivery/consumption between the Port Pair. New Sink Sink at the end of a Power Role Swap or Fast Role Swap which has transition from being the Initial Source. New Source Source at the end of a Power Role Swap or Fast Role Swap which has transition from being the Initial Sink. Non-interruptible There cannot be any unexpected Messages during an AMS; it is therefore Non-interruptible. An AMS starts when the first Message in the AMS has been sent (i.e., a GoodCRC Message has been received acknowledging the Message). See Section 8.3.2.1.3, "Atomic Message Sequences". OCP Over-Current Protection. OTP Over-Temperature Protection. OVP Over-Voltage Protection. Packet One entire unit of PD communication including a Preamble, SOP*, Payload, CRC and EOP as defined in Section 5.6, "Packet Format". Passive Cable Cable with a USB plug on each end at least one of which is a Cable Plug supporting SOP’ that does not incorporate data bus signal conditioning circuits. Supports the Structured VDM Discover Identity to determine its characteristics (Electronically Marked Cable see [USB Type-C 2.4]). Note: This specification does not discuss Passive Cables that are not Electronically Marked. Passive Cable VDO VDO defining the Capabilities of a Passive Cable. Payload Data content of a Packet, provided to/from the Protocol Layer. PD USB Power Delivery PD Capable A Port that supports USB Power Delivery. PD Connection See Connected. PD Power The output power, in Watts, of a Source, as specified by the manufacturer and expressed in Fixed Supply PDOs as defined in Section 10, "Power Rules". PD SID See USB-IF PD SID. PDO See Power Data Object. PDP See PD Power. PDP Rating The PDP Rating is the same as the Manufacturer declared PDP for a Source Port except where there is a fractional value, in which case the PDP Rating corresponds to the integer part of the Manufacturer declared PDP Rating (see Section 6.4.11.2, "Port Maximum PDP Field"). PDUSB USB Device Port or USB Host Port that is both PD Capable and capable of USB Communication. See also PDUSB Host, PDUSB Device and PDUSB Hub. PDUSB Device A USB Device with a PD Capable UFP. A PDUSB Device is only addressed by SOP Packets. PDUSB Host A USB Host which is PD Capable on at least one of its DFPs. A PDUSB Host is only addressed by SOP Packets. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 47 PDUSB Hub A port expander USB Device with a UFP and one or more DFPs which is PD Capable on at least one of its Ports. A PDUSB Hub is only addressed by SOP Packets. A self-powered PDUSB Hub is treated as a USB Type-C Multi-Port Charger. PDUSB Peripheral A USB Device with a PD Capable UFP which is not a PDUSB Hub. A PDUSB Peripheral is only addressed by SOP Packets. PE See Policy Engine. Peripheral A physical entity that is Attached to a USB cable and is currently operating as a USB Device. PHY Layer The Physical Layer responsible for sending and receiving Messages across the USB Type-C CC wire between a Port Pair. Policy Policy defines the behavior of PD Capable parts of the system and defines the Capabilities it Advertises, requests made to (re)Negotiate power and the responses made to requests received. Policy Engine The Policy Engine interprets the Device Policy Manager’s input to implement Policy for a given Port and directs the Protocol Layer to send appropriate Messages. Port An interface typically exposed through a receptacle, or via a plug on the end of a hard-wired captive cable. USB Power Delivery defines the interaction between a Port Pair. Port Pair Two Attached PD Capable Ports. Port Partner A Contract is Negotiated between a Port Pair connected by a USB cable. These ports are known as Port Partners. Power Conductor The wire that delivers power from the Source to Sink. For example, USB’s VBUS. Power Consumer See Consumer. Power Data Object Data Object used to expose a Source Port’s or Sink Port’s power Capabilities as part of a Source_Capabilities / EPR_Source_Capabilities or Sink_Capabilities / EPR_Sink_Capabilities Message respectively. Fixed Supply, Variable Supply and Battery Supply Power Data Objects are defined; SPR Mode uses all four while EPR Mode uses only Fixed Supply and AVS PDOs. Power Delivery Mode Operation after a Contract has initially been established between a Port Pair. This Mode persists during normal Power Delivery operation, including after a Power Delivery Mode. Power Delivery Mode can only be exited by Detaching the Ports, applying a Hard Reset or by the Source removing power (except when the Initial Source removes power from VBUS during the Power Role Swap procedure). Power Provider See Provider. Power Role A Port Partner will be in one of two Power Roles; either Source or Sink. Power Role Swap Process of exchanging the Source and Sink Power Roles between Port Partners. Power Rules Define voltages and current ranges that are offered by compliant USB Power Delivery Sources and used by a USB Power Delivery Sink for a given value of PDP Rating. See Section 10, "Power Rules". PPS See Programmable Power Supply. PPS Mode An SPR Source, currently operating as an PPS, is said to be operating in PPS Mode. Preamble Start of a transmission which is used to enable the receiver to lock onto the carrier. The Preamble consists of a 64-bit sequence of alternating 0s and 1s starting with a "0" and ending with a "1" which is not 4b5b encoded. Product Type Product categorization returned as part of the Discover Identity Command. Product Type VDO VDO identifying a certain Product Type in the ID Header VDO of a Discover Identity Command. Product VDO The Product VDO contains identity information relating to the product. Programmable Power Supply A power supply, operating in SPR Mode, whose output voltage can be programmatically adjusted in small increments over its Advertised range and has a programmable output current fold back (note that the SPR AVS and EPR AVS does not).The Capabilities are exposed by the SPR Programmable Power Supply APDO (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). Protocol Error An unexpected Message during an Atomic Message Sequence. A Protocol Error during an AMS will result in either a Soft Reset or a Hard Reset. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 48 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Layer The entity that forms the Messages used to communicate information between Port Partners. Provider A PD Port (typically a USB Host, Hub, or Charger DFP) that can source power over the power conductor (e.g., VBUS). This corresponds to a USB Type-C Port with Rp asserted on its CC wire. Provider/Consumer A Provider with the additional capability to act as a Consumer. This corresponds to a Dual-Role Power Port with Rp asserted on its CC wire. PS1 PS2 PS3 Classification of electrical power as defined in [IEC 62368-1]. PSD Sink which draws power but has no other USB or Alternate Mode communication function e.g., a power bank. Ra Prior to application of VCONN, a powered cable applies a pull-down resistor Ra on its VCONN pin. Rd Pull-down resistor on the USB Type-C CC wire used to indicate that the Port is a Sink (see [USB Type-C 2.4]). RDO See Request Data Object. Re-attach Attach of the Port Pair by a cable after a previous Detach. Re-negotiate See Re-negotiation. Re-negotiated See Re-negotiation. Re-negotiation A process wherein one of the Port Partners wants to alter the Negotiated Contract. Request Message used by a Sink Port to Negotiate a Contract; refers to either a Request/EPR_Request Message. Request Data Object Data Object used by a Sink Port to Negotiate a Contract as a part of a Request/EPR_Request Message. Responder The receiver of a Command request sent by an Initiator that replies with a Command response. Revision Major release of the USB Power Delivery specification. Each Revision will have variousVersions associated with it. Revision 1.0 Deprecated major Revision of the USB Power Delivery Specification. Revision 2.0 Superseded major Revision of the USB Power Delivery Specification as defined in [USBPD 2.0], with which this specification is compatible. Revision 3.x Current major Revisions of the USB Power Delivery Specification. Rp Pull-up resistor on the USB Type-C CC wire used to indicate that the Port is a Source (see [USB Type-C 2.4]). Safe Operation Sources must have the ability to tolerate vSafe5V applied by both Port Partners. Shared Capacity Charger As defined in [USB Type-C 2.4]. This maps to a Charger with multiple Managed Capability Ports. Shared Capacity Group As defined in [USB Type-C 2.4]. This maps to a group with Managed Capability Ports. SID See Standard ID. Signaling A Preamble followed by an ordered set of four K-codes used to indicate a particular line symbol e.g., Hard Reset as defined in Section 5.4, "Ordered Sets". Signaling Scheme Physical mechanism used to transmit bits. Only the BMC Signaling Scheme is defined in this specification. Note: The BFSK Signaling Scheme supported in Revision 1.0 of this specification has been Deprecated. Single-Role Port A Port that is only capable of operating either as a Source or Sink, but not both. E.g., the port is not a DRP. Sink The Port consuming power from VBUS; most commonly a USB Device. Sink Capabilities Capabilities wanted by a Sink. Sink Directed Charge A charging scheme whereby the Sink connects the Source to its Battery through safety and other circuitry. When the SPR PPS Current Limit feature is activated, the Source automatically controls its output current by adjusting its output voltage. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 49 Sink Port Port operating as a Sink. Sink Standby During Sink Standby the Sink reduces its current draw to iSnkStdby Soft Reset A process that resets the PD communications engine to its default state. SOP K-code marker used for communication between Port Partners. See also Start of Packet. SOP Communication Communication using SOP Packets also implies that an AMS is being followed. SOP Packet Any Power Delivery Packet which starts with an SOP. SOP’ Communication Communication with a Cable Plug using SOP’ Packets, also implies that an AMS is being followed. SOP’ Packet Any Power Delivery Packet which starts with an SOP’ used to communicate with a Cable Plug. SOP’’ Communication Communication with a Cable Plug using SOP’’ Packets, also implies that an AMS is being followed. SOP’’ Packet Any Power Delivery Packet which starts with an SOP’’ used to communicate with a Cable Plug when SOP’ Packets are being used to communicate with the other Cable Plug. SOP’ SOP’’ K-code marker used for communication between a Port and a Cable Plug. See also Start of Packet. SOP* Used to generically refer to K-code markers: SOP, SOP’ and SOP’’. See also Start of Packet. SOP* Communication Communication using SOP* Packets, also implies an AMS is being followed. SOP* Packet A term referring to any Power Delivery Packet starting with either SOP, SOP’, or SOP’’. Source The Power Role a Port is operating in to supply power over VBUS; most commonly a USB Host or Hub downstream port. Source Capabilities Capabilities offered by a Source. Source Port Port operating as a Source. Specification Revision See Revision. SPM See System Policy Manager. SPR See Standard Power Range. SPR AVS An SPR Source whose output voltage can be adjusted to an operating voltage within its Advertised range. Unlike SPR PPS, it does not support current limit. The SPR AVS Capabilities are exposed by the SPR AVS APDO (see Section 6.4.1.2.4.2, "SPR Adjustable Voltage Supply APDO"). SPR AVS Mode A SPR Source, currently operating in an SPR AVS Contract, is said to be operating in SPR AVS Mode. SPR Capabilities An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) has at least one Power Data Object for vSafe5V followed by up to 6 additional Power Data Objects. SPR Contract Explicit Contract Negotiated, in SPR Mode, based on SPR (A)PDOs. SPR Mode The classic mode of PD operation where Explicit Contracts are Negotiated using SPR (A)PDOs. SPR (A)PDO Fixed Supply PDO that offers up to 20V and no more than 100W. Variable Supply PDO whose Maximum voltage offers up to 21V and no more than 100W. Battery Supply PDO whose Maximum voltage offers up to 21V and no more than 100W. Adjustable Voltage Supply (AVS) APDO whose Maximum voltage is up to 20V and no more than 100W. Programmable Power Supply (PPS) APDO whose Maximum voltage is up to 21V and no more than 100W. SPR PPS A power supply whose output voltage and output current can be programmatically adjusted in small increments over its Advertised range. It supports current limit unlike SPR AVS and EPR AVS. The Capabilities are exposed by the Programmable Power Supply APDOs (see Section 6.4.1.2.4, "Augmented Power Data Object (APDO)"). SPR PPS Mode A power supply, currently operating in an SPR PPS Contract, is said to be operating in SPR PPS Mode. SPR Sink A Sink which only supports SPR Mode and does not support EPR Mode. SPR Sink Port A Port exposed on an SPR Sink. SPR Source A Source which only supports SPR Mode and does not support EPR Mode. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 50 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SPR Source Port A Port exposed on an SPR Source. Standard ID 16-bit unsigned value assigned by the USB-IF to a given industry standards organization’s specification. Standard or Vendor ID Generic term referring to either a VID or a SID. SVID is used in place of the phrase “Standard or Vendor ID.” Standard Power Range Only the Source_Capabilities and the Request Messages are allowed to Negotiate SPR Explicit Contracts. The EPR Messages (the EPR_Source_Capabilities Message and the EPR_Request Message) are not allowed to be used while in SPR Mode. Start of Packet K-code marker used to delineate the start of a Packet. State PD state machine state as defined in Section 6.12, "State behavior" and Section 8.3.3, "State Diagrams" state machines. Structured VDM See Structured Vendor Defined Message. Structured VDM Header The VDM Header for a Structured Vendor Defined Message. Structured Vendor Defined Message A Vendor Defined Message where the contents and usage of bits 14...0 of the VDM Header are defined by this specification. SVDM See Structured Vendor Defined Message. SVID See Standard or Vendor ID. Swap Standby During Swap Standby the Source does not drive VBUS and the Sink's current draw does not exceed iSnkSwapStdby. System Policy Overall system Policy generated by the system, broken up into the policies required by each Port Pair to affect the System Policy. It is programmatically fed to the individual devices for consumption by their Policy Engines. System Policy Manager Module running on the USB Host. It applies the System Policy through communication with PD Capable Consumers and Providers that are also connected to the USB Host via USB. Test Frame Frame consisting of a Preamble, SOP*, followed by test data (See Section 5.9, "Built in Self-Test (BIST)"). Test Pattern Continuous stream of test data in a given sequence (See Section 5.9, "Built in Self-Test (BIST)"). Tester The Tester is assumed to be a piece of test equipment that manages the BIST testing process of a PD UUT. UFP See Upstream Facing Port. UFP VDO VDO returned by the UFP containing Capabilities. UI See Unit Interval. Unchunked See Unchunked Extended Message. Unchunked Extended Message Extended Message that has been transmitted whole without using Chunking. Unexpected Message Message that a Port supports but has been received in an incorrect State. Unit Interval The time to transmit a single data bit on the wire. Unit Under Test The PD device that is being tested by the Tester and responds to the initiation of a particular BIST test sequence. Unrecognized Message Message that a Port does not understand e.g., a Message using a Reserved Message type, a Message defined by a higher specification Revision than the Revision this Port supports, or an Unstructured Vendor Defined Message for which the VID is not recognized. Unstructured VDM See Unstructured Vendor Defined Message. Unstructured VDM Header The VDM Header for an Unstructured Vendor Defined Message. Unstructured Vendor Defined Message A Vendor Defined Message where the contents of bits 14...0 of the VDM Header are undefined. Unsupported Message Message that a Port recognizes but does not support. This is a Message defined by the specification, but which is not supported by this Port. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 51 Upstream Facing Port Indicates the Port’s position in the USB topology typically a Port on a Device as defined in [USB Type-C 2.4]. At connection, the Port defaults to operation as a USB Device (when USB Communication is supported) and Sink. USB Attached State Synonymous with the [USB 2.0] and [USB 3.2] definition of the Attached state USB Communication Transfer of USB data Packets as defined in [USB 2.0] and [USB 3.2]. USB Default Operation Operation of a Port at Attach or after a Hard Reset where the DFP Source applies vSafe5V on VBUS and the UFP Sink is operating at vSafe5V as defined in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2]. USB Device Either a Hub or a Peripheral device as defined in [USB 2.0], [USB 3.2] and [USB4]. USB Host The computer system where the USB Host controller is installed as defined in [USB 2.0], [USB 3.2] and [USB4]. USB Hub See Hub. USB Powered State Synonymous with the [USB 2.0] and [USB 3.2] definition of the powered state. USB Safe State State of the USB Type-C connector when there are pins to be re-purposed (see [USB Type-C 2.4]) so they are not damaged by and do not cause damage to their Port Partner. USB Type-A Term used to refer to any A plug or receptacle including USB Micro-A plugs and USB Standard- A plugs and receptacles. USB Micro-AB receptacles are assumed to be a combination of USB Type-A and USB Type-B. USB Type-B Terms used to refer to any B-plug or receptacle including USB Micro-B plugs and USB Standard- B plugs and receptacles, including the PD and non-PD versions. USB Micro-AB receptacles are assumed to be a combination of USB Type-A and USB Type-B. USB Type-C Term used to refer to the USB Type-C connector plug, or receptacle as defined in [USB Type-C 2.4]. USB Type-C Multi-Port Charger A product that exposes multiple USB Type-C Source Ports for the purpose of charging multiple connected USB Devices as defined in [USB Type-C 2.4]. USB-C® Port Control Module in a PD Capable device which controls Attach/Detach and either detects or sets the Rp value. USB-IF PD SID Standard ID allocated to this specification by the USB Implementer’s Forum. USB4® Mode Device is operating in a Mode as defined in [USB4]. UUT See Unit Under Test. Variable Supply A poorly regulated power supply that is not a Battery. This is exposed by the Variable Supply PDO (see Section 6.4.2, "Request Message"). VBUS The VBUS wire delivers power from a Source to a Sink. VCONN Once the connection between USB Host and device is established, the CC pin (CC1 or CC2) in the receptacle that is not connected via the CC wire through the standard cable is re-purposed to source VCONN to power circuits in a Cable Plug, VCONN Powered Accessory or VCONN Powered USB Device (see [USB Type-C 2.4]). VCONN Powered Accessory An accessory that is powered from VCONN to operate in an Alternate Mode (see [USB Type-C 2.4]). VCONN Powered USB Charge Through Device A CT-VPD is a VPD with an additional port for connecting a Source (e.g., a Charger) as defined in [USB Type-C 2.4]. When no Charger is connected, a CT-VPD behaves as a VPD. When a Charger is connected, no PD communication to the CT-VPD itself is possible as CC is connected to the Charger port. Hence all PD communication then is with the Charger and the cable with which it is connected. Table 1.4 Terms and Abbreviations (Continued) Term Description Page 52 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 1.7 Parameter Values The parameters in this specification are expressed in terms of absolute values. For details of how each parameter is measured in compliance please see [USBPDCompliance]. 1.8 Changes from Revision 3.0 Extended Power Range (EPR) including Adjustable Voltage Supply (AVS) has been added. 1.9 Compatibility with Revision 2.0 This Revision of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware. Please see Section 2.3, "USB Power Delivery Capable Devices" for more details of the mechanisms defined to enable compatibility. VCONN Powered USB Device A captive cable USB Device that can be powered by either VCONN or VBUS as defined in [USB Type- C 2.4]. A VPD is a captive cable USB Device that can be powered by either VCONN or VBUS and only responds to SOP’ Communication as defined in the Tables in Section 6.12, "State behavior"). It only responds to Messages sent with a Specification Revision of at least Revision 3.x. A VPD is not allowed to support Alternate Modes. The term VPD refers to either a VPD or a CT-VPD with no Charger connected. VCONN Source The USB Type-C Port responsible for sourcing VCONN. VCONN Swap Process of exchanging the VCONN Source between Port Partners. VDEM See Vendor Defined Extended Message. VDM See Vendor Defined Message. VDM Header The first Data Object following the Message Header in a Vendor Defined Message. The VDM Header contains the SVID relating to the VDM being sent and provides information relating to the Command in the case of a Structured VDM (see Section 6.4.4, "Vendor Defined Message"). VDO See Vendor Data Object. Vendor Data Object Data Object used to send Vendor specific information as part of a Message. Vendor Defined Extended Message PD Extended Message defined for vendor/standards usage. A VDEM does not define any structure and Messages can be created in any manner that the vendor chooses. Vendor Defined Message PD Data Message defined for vendor/standards usage. These are further partitioned into Structured Vendor Defined Messages, where Commands are defined in this specification, and Unstructured Vendor Defined Messages which are entirely vendor defined (see Section 6.4.4, "Vendor Defined Message"). Vendor ID 16-bit unsigned value assigned by the USB-IF to a given Vendor. Version A minor release of the USB Power Delivery specification associated with a particular Revision. Version numbers are also defined in VDMs. VI Same as power (i.e., voltage * current = power) VID See Vendor ID. VPD See VCONN Powered USB Device. Table 1.4 Terms and Abbreviations (Continued) Term Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 53 2 Overview This section contains no Normative requirements. 2.1 Introduction USB Power Delivery (PD) defines the mechanisms for pairs of directly Attached Ports (also referred to as Port Partners or Port Pairs) to Negotiate voltage, current and/or direction of power flow over the USB cable. It uses the USB Type-C® connector's CC wire as the communications channel. The PD mechanisms operate independently of and supersede other USB methods defined in [USB 2.0], [USB 3.2], [USBBC 1.2] and [USB Type-C 2.4]. USB Power Delivery also defines sideband mechanisms used for configuration management of USB Type-C devices and cables. Using Structured Vendor Defined Messages (Structured VDMs), PD facilitates discovery of device and cables features and performance. Structured VDMs are also used to enter/exit some Active Modes, either USB-based (e.g., USB4® Mode) or USB Type-C Alternate Modes. Alternate Modes are associated with Standard or Vendor IDs (SVIDs) and can be either standard (e.g., DisplayPort Alternate Mode) or proprietary (e.g., Intel Thunderbolt™ 3). 2.1.1 Power Delivery Source Operational Contracts A PD Source will be in one of three Contracts:  Default Contract which it enters immediately following a Connect where the Source provides 5V and Advertises the amount of current it can deliver using the Rp value as defined in [USB Type-C 2.4]. A Source in a Default Contract will remain in this Contract until the Sink is Detached or the Source and Sink Negotiate and enter an Explicit Contract.  Implicit Contract which immediately follows a Power Role Swap or Fast Role Swap and is transitory. The PD Source provides 5V and Advertises the amount of current it can deliver using the Rp value as defined in [USB Type-C 2.4]. A Source in an Implicit Contract will immediately Negotiate with the Sink and enter an Explicit Contract.  Explicit Contract is the state of the Source after any PD power Negotiation consisting of the Source sending a Source_Capabilities Message, the Sink responding with a Request Message, the Source acknowledging the request with an Accept Message and finally the Source sends a PS_RDY Message when the Source is ready to deliver the requested power. This is the normal operational state for PD. A Source in an Explicit Contract will remain in an Explicit Contract during and after a Re-negotiation of its Contract and will exit the Explicit Contract when:  Disconnected from the Sink where it will restart in a Default Contract when reconnected to the Sink.  Following a Hard Reset where it will restart as if it were Detached then Attached to the Sink.  Following a Power Role Swap or Fast Role Swap where it will enter an Implicit Contract.  Following USB Type-C Error Recovery which is an electrical Detach/Re-attach (remove and assert Rp). 2.1.2 Power Delivery Contract Negotiation Contracts Negotiated using the USB Power Delivery Specification supersede any and all previous power contracts established whether from standard [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] mechanisms. While operating in Power Delivery Mode there will be a Contract in place (either Explicit Contract or Implicit Contract) that determines the power level available and the direction of that power. The Port Pair will remain in Power Delivery Mode until the Port Pair is Detached, there is a Hard Reset, or USB Type-C Error Recovery, or the Source removes power except as part of the Power Role Swap or Fast Role Swap processes. Note: [USB4] does not define a default power, rather relies on a PD power Contract. When first Attached the [USB4] device operates in [USB 3.2] Mode which is its USB Default Operation. An Explicit Contract is Negotiated by the process of the Source sending a set of Capabilities, from which the Sink is required to request a particular capability and then the Source accepting this request. Page 54 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 An Implicit Contract is the specified level of power allowed in particular states (i.e., during and after a Power Role Swap or Fast Role Swap). Implicit Contracts are temporary; Port Pairs are required to immediately Negotiate an Explicit Contract. Each Provider has a Local Policy, governing power allocation to its Ports. Consumers also have their own Local Policy governing how they draw power. A System Policy can be enacted over USB that allows modification to this Local Policy and hence management of overall power allocation in the system. When PD Capable devices are Attached to each other, the DFPs and UFPs initially default to standard USB Default Operation. The DFP supplies vSafe5V and the UFP draws current in accordance with the rules defined by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] specifications. After Power Delivery Negotiation has taken place, power can be supplied at higher, or lower, voltages and higher currents than defined in these specifications. It is also possible to:  Do a Power Role Swap or Fast Role Swap to exchange the Power Roles such that the DFP receives power and the UFP supplies power.  Do a Data Role Swap such that the DFP becomes the UFP and vice-versa.  Do a VCONN Swap to change the Port supplying VCONN to the cable.  Enter into EPR Mode.  Enter into USB4® Mode.  Enter into Alternate Modes.  Send Vendor Defined Messages. Prior to the First Explicit Contract only the Source Port, which is also the VCONN Source, can communicate with the Attached cable assembly. This is important where 5A and EPR capability are marked as well as other details of the cable assembly such as the supported speed. Cable Discovery, determining whether the cable can communicate, can occur on initial Attachment of a Port Pair before an Explicit Contract has been established. It is also possible to carry out Cable Discovery after a Power Role Swap or Fast Role Swap prior to re-establishing an Explicit Contract, where the UFP is the Source, and an Implicit Contract is in place. Cable Discovery can be carried out after an Explicit Contract has been established, if the cable has not yet been discovered. 2.1.3 Other Uses for Power Delivery Once an Explicit Contract is in place, PD can be used to manage the Ports and cables for non-power related functionality. PD is used to enter the USB4® Mode of operation. Ports and cables can support functionality beyond power. For example, a cable can have active components that require VCONN power or a Port/cable can support a video display Alternate Mode such as DisplayPort. PD defines an infrastructure to discover these additional Capabilities and Modes that include:  Discovering a Port or Cable Plug's Capabilities.  Discovery of the SVIDs a Port or Cable Plug supports.  Discovery of the Modes a Port or Cable Plug supports.  Entry into a Mode supported by the Port and/or Cable Plug.  Exiting Modes supported by the Port and/or Cable Plug. 2.2 Compatibility with Revision 2.0 Revision 3.x of the USB Power Delivery specification is designed to be fully inter-operable with [USBPD 2.0] systems using BMC Signaling over the [USB Type-C 2.4] connector and to be compatible with Revision 2.0 hardware. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 55 This specification mandates that all Revision 3.x systems fully support Revision 2.0 operation. They must discover the supported Revision used by their Port Partner and any connected Cable Plugs and revert to operation using the lowest common Revision number (see Section 6.2.1.1.5, "Specification Revision"). This specification defines Extended Messages containing data of up to 260 bytes (see Section 6.2.1.2, "Extended Message Header"). These Messages can be larger than expected by existing PHY HW. To accommodate Revision 2.0 based systems a Chunking mechanism is mandated such that Messages are limited to Revision 2.0 sizes unless it is discovered that both systems support the longer Message lengths. This specification includes changes to the Vendor Data Objects (VDO) used in the discovery of passive/active marked cables and Alternate Mode Adapters (AMA) (see Section 6.4.4.2, "Structured VDM"). To enable systems to determine which VDO format is being used the Structured Vendor Defined Message (SVDM) Version number has been incremented to 2.x. Version numbers have also been incorporated into the VDOs themselves to facilitate future changes if these become necessary. 2.3 USB Power Delivery Capable Devices Some examples of USB Power Delivery capable devices can be seen in Figure 2.1, "Logical Structure of USB Power Delivery Capable Devices" (a USB Host, a USB Device, a Hub, and a Charger). These are given for reference only and are not intended to limit the possible configurations of products that can be built using this specification. Figure 2.1 Logical Structure of USB Power Delivery Capable Devices Each USB Power Delivery capable device is assumed to be made up of at least one Port. Providers are assumed to have a Source and Consumers a Sink. Each device contains one, or more, of the following components:  UFPs that:  Sink Power.  Communicate using SOP Packets.  Optionally Communicate using SOP’ Packets/SOP’’ Packets.  Optionally source power (a Dual-Role Power Device).  Optionally communicate via USB.  Optionally support Alternate Modes.  DFPs that: USB Host UFP USB Device Power Storage External power USB Hub DFP Power Storage External power USB Charger UFP Power Storage External power External power Power Storage DFP DFP Optional Power input Optional Feature Multiple Power inputs/outputs Multiple Power outputs Power input Legend Page 56 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Source Power  Communicate using SOP Packets.  Optionally Communicate using SOP* Packets.  Optionally Sink power (a Dual-Role Power Device).  Optionally communicate via USB.  Optionally support Alternate Modes.  A Source that can be:  An externally powered source (e.g., AC powered).  Power Storage (e.g., Battery/Power Bank).  Derived from another Port (e.g., bus-powered Hub).  A Sink that can be:  Power Storage (e.g., a Battery/Power Bank).  Used to power internal functions.  Used to power devices Attached to other devices (e.g., a bus-powered Hub).  A VCONN Source that:  Can be either Port Partner, either the DFP/UFP or Source/Sink.  Powers the Cable Plug(s).  Powers VPDs (VCONN Powered USB Devices).  Is the only Port allowed to talk to the Cable Plug(s) at any given time. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 57 2.4 SOP* Communication 2.4.1 Introduction The Start of Packet (or SOP) is used as an addressing scheme to identify whether the communications were intended for one of the Port Partners (SOP Communication) or one of the Cable Plugs (SOP’ Communication/SOP’’ Communication). SOP/SOP’ and SOP’’ are collectively referred to as SOP*. All SOP* Communications take place over a single wire (CC). The term Cable Plug in the SOP’ Communication/SOP’’ Communication case is used to represent a logical entity in the cable which is capable of PD Communication, and which might or might not be physically located in the plug. Note: There are there are other SOPs defined for special operation such as debug which are not discussed here. The following sections describe how this addressing scheme operates for Port-to-Port and Port to Cable Plug communication. 2.4.2 SOP* Collision Avoidance For all SOP* the Source co-ordinates communication to avoid bus collisions by allowing the Sink to initiate messaging when it does not need to communicate itself. Once an Explicit Contract is in place, the Source manipulates its Rp value (3A) to indicate to the Sink that it can initiate an Atomic Message Sequence (AMS). This AMS can be communication with the Source or with one of the Cable Plugs. As soon as the Source itself needs to initiate an AMS, it will manipulate its Rp value (1.5A) to indicate this to the Sink. The Source then waits for any outstanding Sink SOP* Communication to complete before initiating an AMS itself. In all cases, the Port initiating an AMS waits for CC to be Idle before putting the Message on CC. 2.4.3 SOP Communication SOP Communication is used for Port-to-Port communication between the Source and the Sink. SOP Communication is recognized by both Port Partners but not by any intervening Cable Plugs. SOP Communication takes priority over other SOP* Communications since it is critical to complete power related operations as soon as possible. 2.4.4 SOP'/SOP'' Communication with Cable Plugs SOP’ Communication is recognized by electronics in one Cable Plug (see [USB Type-C 2.4]). SOP’’ Communication can also be supported when SOP’ Communication is also supported. SOP’ and SOP’’ assignment in the cable assembly is fixed and does not change dynamically. SOP Communication between the Port Partners is not recognized by the Cable Plug. Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)" outlines the usage of SOP* Communications between a VCONN Source (DFP/UFP) and the Cable Plugs. Since all SOP* Communications take place over a single wire (CC), the SOP* Communication periods must be coordinated to prevent important communication from being blocked. For a product which does not recognize SOP/SOP’ or SOP’’ Packets, this will look like a non-Idle channel, leading to missed Packets and retries. Communications between the Port Partners take precedence meaning that communications with the Cable Plug can be interrupted but will not lead to a Soft Reset or Hard Reset. When a Default Contract or Implicit Contract is in place (e.g., at startup, after a Power Role Swap or Fast Role Swap) only the Source Port that is supplying VCONN is allowed to send Packets to a Cable Plug (SOP’) and is allowed to respond to Packets from the Cable Plug (SOP’) with a GoodCRC Message in order to discover the Cable Plug's characteristics (see Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)"). During this phase, all communication with the Cable Plug is initiated and controlled by the VCONN Source which acts to prevent conflicts between SOP Packets and SOP’ Packets. The Sink does not communicate with the Cable Plug and Discards any SOP’ Packets received. When an Explicit Contract is in place, only the VCONN Source (either the DFP or the UFP) can communicate with the Cable Plug(s) using SOP’ Packets/SOP’’ Packets (see Figure 2.2, "Example SOP' Communication between VCONN Source and Cable Plug(s)"). During this phase, all communication with the Cable Plug is initiated and controlled by the VCONN Source which acts to prevent conflicts between SOP* Packets. The Port that is not the VCONN Source is not Page 58 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 allowed to communicate with the Cable Plug and does not recognize any SOP’ Packets/SOP’’ Packets received. Only the DFP, when acting as a VCONN Source, is allowed to send SOP* Packets to control the entry and exiting of Modes and to manage Modal Operation. Figure 2.2 Example SOP' Communication between VCONN Source and Cable Plug(s) VCONN Source (DFP/UFP) SOP signaling SOP’ signaling SOP’’ signaling Cable Plug1 (SOP’’) Electronically Marked Cable Cable Plug1 (SOP’) VCONN Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 59 2.5 Operational Overview A USB Power Delivery Port supplying power is known as a Source and a Port consuming power is known as a Sink. There is only one Source Port and one Sink Port in each PD Connection between the Port Partners. At Attach the Source Port (the Port with Rp asserted see [USB Type-C 2.4]) is also the DFP and VCONN Source. At Attach the Sink Port (the Port with Rd asserted) is also the UFP and is not the VCONN Source. The original USB PD specification allowed Sources to deliver up to 100W. This classic Mode of operation is referred to as the Standard Power Range (SPR). The First Explicit Contract, the first Contract after a Default Contract or Implicit Contract, is always an SPR Contract. There is an Optional higher power Mode referred to as the Extended Power Range (EPR) where the Source is allowed to deliver up to 240W. The EPR Mode can only be entered from the SPR Mode. The entry process is designed to prevent accidental entry into this higher power Mode. It can be entered only when an SPR Explicit Contract is in place and both the Source Port and Sink Port as well as the cable support EPR. The Source/Sink Power Roles, DFP/UFP Data Roles and VCONN Source role can all subsequently be swapped orthogonally to each other. A Port that supports both Source and Sink Power Roles is called a Dual-Role Power Port (DRP). A Port that supports both DFP and UFP Data Roles is called a Dual-Role Data Port (DRD). When USB Communications capability is supported in the DFP Data Role then the Port will also be able to act as a USB Host. Similarly, when USB Communications capability is supported in the UFP Data Role then the Port will also be able to act as a USB Device. The following sections describe the high-level operation of ports taking on the roles of DFP, UFP, Source and Sink. For details of how PD maps to USB states in a PDUSB Device see Section 9.1.2, "Mapping to USB Device States". 2.5.1 Source Operation The Source operates differently depending on its Attachment status:  At Attach (no PD Connection or Contract):  For a Source-only Port the Source detects Sink Attachment.  For a DRP that toggles between Source and Sink operation, the Port becomes a Source Port on Attachment of a Sink  The Source then supplies vSafe5V.  Before PD Connection (no PD Connection or Contract):  Prior to sending Source_Capabilities Messages the Source can detect the Cable Capabilities and Advertises its Capabilities depending on the Cable Capabilities detected:  The default current carrying capability of a USB Type-C cable is 3A.  The Source can attempt to communicate with one of the Cable Plugs using SOP’ Packets. If the Cable Plug responds, then communication takes place to discover the cable's Capabilities (e.g., 5A capable).  The Source periodically Advertises its Capabilities by sending Source_Capabilities Messages every tTypeCSendSourceCap.  Establishing PD Connection (no PD Connection or Contract):  Presence of a PD Capable Port Partner is detected either:  By receiving a GoodCRC Message in response to a Source_Capabilities Message.  By receiving Hard Reset Signaling.  Establishing the First Explicit Contract after an Attach, Hard Reset, USB Type-C Error Recovery or Implicit Contract as a result of a Power Role Swap or Fast Role Swap: Page 60 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Source receives a Request Message from the Sink and, if this is a Valid request, responds with an Accept Message followed by a PS_RDY Message when its power supply is ready to source power at the agreed level. At this point an Explicit Contract has been agreed.  A DFP that does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  When in an Explicit Contract (PE_SRC_Ready State):  The Source processes and responds (if a response is required) to all Messages received and sends appropriate Messages whenever its Local Policy requires:  The Source informs the Sink whenever its Capabilities change, by sending a Source_Capabilities Message.  The Source responds to a Sink Request Message with the Capabilities mismatch bit set, by sending a Source_Capabilities Message with its maximum available power.  The Source will always have an Rp value asserted on its CC wire used for Collision Avoidance.  When this Port is a DRP the Source can initiate or receive a request for the exchange of Power Roles. After the Power Role Swap this Port will be a Sink and in an Implicit Contract until an Explicit Contract is Negotiated immediately afterwards.  When this Port is a DRD the Source can initiate or receive a request for an exchange of Data Roles. After a Data Role Swap the DFP (USB Host) becomes a UFP (USB Device). The Port remains a Source and the VCONN Source role remains unchanged.  The Source can initiate or receive a request for an exchange of VCONN Source role. During a VCONN Swap VCONN is applied by both Ports (make before break). The Port remains a Source and DFP/ UFP Data Roles remain unchanged.  The Source when it is the VCONN Source can communicate with a Cable Plug using SOP’ Communication or SOP’’ Communication at any time it is not engaged in any other SOP Communication:  If SOP Packets are received by the Source, during SOP’ Communication or SOP’’ Communication, the SOP’ Communication or SOP’’ Communication is immediately terminated (the Cable Plug times out and does not retry).  If the Source needs to initiate an SOP Communication during an ongoing SOP’ Communication or SOP’’ Communication (e.g., for a Capabilities change) then the SOP’ Communication or SOP’’ Communications will be interrupted.  When the Source Port is also a DFP:  The Source can control the entry and exiting of Modes in the Cable Plug(s) and control Modal Operation.  The Source can initiate Unstructured VDMs or Structured VDMs.  The Source can control the entry and exiting of Modes in the Sink and control Modal Operation using Structured VDMs.  Detach or communications failure:  A Source detects plug Detach and takes VBUS down to vSafe5V within tSafe5V and vSafe0V within tSafe0V (i.e. using USB Type-C Detach detection via CC).  When the Source detects the failure to receive a GoodCRC Message in response to a Message within tReceive:  Leads to a Soft Reset, within tSoftReset of the CRCReceiveTimer expiring. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 61  If the Soft Reset process cannot be completed a Hard Reset will be issued within tHardReset of the CRCReceiveTimer to restore VBUS to USB Default Operation within ~1-1.5s:  When the Source is also the VCONN Source, VCONN will also be power cycled during the Hard Reset.  When the Source operating in SPR PPS Mode fails to receive periodic communication (e.g., a Request Message) from the Sink within tPPSTimeout:  Source issues a Hard Reset and takes VBUS to vSafe5V.  When the Source operating in the EPR Mode fails to receive periodic communication (i.e., an EPR_KeepAlive Message or any other Message) from the Sink within tSourceEPRKeepAlive:  Source issues a Hard Reset and takes VBUS to vSafe5V.  Receiving no response to further attempts at communication is interpreted by the Source as an error (see Error handling).  Errors during power transitions will automatically lead to a Hard Reset to restore power to default levels.  Error handling:  Protocol Errors are handled by a Soft_Reset Message issued by either Port Partner, that resets counters, timers and states, but does not change the Negotiated voltage and current or the Port's role (e.g., Source, DFP/UFP, VCONN Source) and does not cause an exit from Modal Operation.  Serious errors are handled by Hard Reset Signaling issued by either Port Partner. A Hard Reset:  Resets protocol as for a Soft Reset but also returns the power supply to USB Default Operation (vSafe0V or vSafe5V output) in order to protect the Sink.  Restores the Port's Data Role to DFP.  Restores the Port's power to its USB default state.  When the Sink is the VCONN Source it removes VCONN then the Source Port is restored as the VCONN Source.  Causes all Active Modes to be exited such that the Source is no longer in Modal Operation.  After a Hard Reset it is expected that the Port Partner will respond within tNoResponse. If this does not occur then nHardResetCount further Hard Resets are carried out before the Source performs additional Error Recovery steps, as defined in [USB Type-C 2.4], by entering the ErrorRecovery state. Page 62 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.5.2 Sink Operation  At Attach (no PD Connection or Contract):  Sink detects Source Attachment through the presence of vSafe5V.  For a DRP that toggles between Source and Sink operation, the Port becomes a Sink Port on Attachment of a Source.  Once the Sink detects the presence of vSafe5V on VBUS it waits for a Source_Capabilities Message indicating the presence of a PD Capable Source.  If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap then it can issue Hard Reset Signaling in order to cause the Source Port to send a Source_Capabilities Message if the Source Port is PD Capable.  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  Establishing PD Connection (no PD Connection or Contract):  The Sink receives a Source_Capabilities Message and responds with a GoodCRC Message.  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  Establishing the First Explicit Contract after an Attach, Hard Reset or Implicit Contract as a result of a Power Role Swap or Fast Role Swap:  The Sink receives a Source_Capabilities Message from the Source and responds with a Request Message. If this is a Valid request the Sink receives an Accept Message followed by a PS_RDY Message when the Source's power supply is ready to source power at the agreed level. At this point the Source and Sink have entered into an Explicit Contract:  The Sink Port can request one of the Capabilities offered by the Source, even if this is the vSafe5V output offered by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2], in order to enable future power Negotiation:  A Sink not requesting any Valid capability with a Request Message results in an error.  A Sink unable to fully operate at the offered Capabilities requests the default capability but in- dicates that it would prefer another power level by setting the Capability Mismatch bit in the Request Message and also providing a physical indication of the failure to the end user (e.g., using an LED).  The Sink does not generate SOP’ Packets or SOP’’ Packets, is not required to detect SOP’ Packets or SOP’’ Packets and Discards them.  During PD Connection (Explicit Contract - PE_SNK_Ready state):  The Sink processes and responds (if a response is required) to all Messages received and sends appropriate Messages whenever its Local Policy requires.  A Sink whose power needs have changed indicates this to the Source with a new Request Message. The Sink Port can request one of the Capabilities previously offered by the Source, even if this is the vSafe5V output offered by [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2], in order to enable future power Negotiation:  Not requesting any capability with a Request Message results in an error.  A Sink unable to fully operate at the offered Capabilities requests an offered capability but indicates a Capabilities Mismatch i.e., that it would prefer another power level also providing a physical indication of the failure to the end user (e.g., using an LED). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 63  A Sink operating in the SPR PPS Mode periodically sends Request Message within tPPSRequest even if its request is unchanged.  A Sink operating in the EPR Mode periodically communicates with the Source (i.e., sends an EPR_KeepAlive Message or any other Message) within tSourceEPRKeepAlive.  The Sink will always have Rd asserted on its CC wire.  When this Port is a DRP, the Sink can initiate or receive a request for the exchange of Power Roles. After the Power Role Swap this Port will be a Source and an Implicit Contract will be in place until an Explicit Contract is Negotiated immediately afterwards.  When this Port is a DRD the Sink can initiate or receive a request for an exchange of Data Roles. After a Data Role Swap the UFP (USB Device) becomes a DFP (USB Host). The Port remains a Sink and VCONN Source role (or not) remains unchanged.  The Sink can initiate or receive a request for an exchange of VCONN Source. During a VCONN Swap VCONN is applied by both ends (make before break). The Port remains a Sink and DFP/UFP Data Roles remain unchanged.  The Sink when it is the VCONN Source can communicate with a Cable Plug using SOP’ Communication or SOP’’ Communication at any time it is not engaged in any other SOP Communication:  If SOP Packets are received by the Sink, during SOP’ Communication or SOP’’ Communication, the SOP’ Communication or SOP’’ Communication is immediately terminated (the Cable Plug times out and does not retry)  If the Sink needs to initiate an SOP Communication during an ongoing SOP’ Communication or SOP’’ Communication (e.g., for a Capabilities change) then the SOP’ Communication or SOP’’ Communications will be interrupted.  When the Sink Port is also a DFP:  The Sink can initiate Unstructured VDMs or Structured VDMs.  The Sink can control the Mode Entry and Mode Exit of Modes in the Source and control Modal Operation (e.g. [USB4]).  Detach or Communications Failure:  A Sink detects the removal of VBUS and interprets this as the end of the PD Connection:  This is unless the vSafe0V is due to either a Hard Reset, Power Role Swap or Fast Role Swap.  A Sink detects plug removal (i.e., absence of Rp or VBUS) and discharges VBUS.  When the Sink detects the failure to receive a GoodCRC Message in response to a Message within tReceive:  Leads to a Soft Reset, within tSoftReset of the CRCReceiveTimer expiring.  If the Soft Reset process cannot be completed a Hard Reset will be issued within tHardReset of the CRCReceiveTimer to restore VBUS to USB Default Operation within ~1-1.5s.  Receiving no response to further attempts at communication is interpreted by the Sink as an error (see Error handling).  When the Sink operating in the SPR PPS Mode fails to send periodic communication (i.e. a Request Message) to the Source within tPPSRequest, the Source will issue a Hard Reset that results in VBUS going to vSafe5V.  When the Sink operating in the EPR Mode fails to send periodic communication (i.e. an EPR_KeepAlive Message or any other Message) to the Source within tSourceEPRKeepAlive the Source will issue a Hard Reset that results in VBUS going to vSafe5V. Page 64 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Errors during power transitions will automatically lead to a Hard Reset to restore power to default levels.  Error handling:  Protocol Errors are handled by a Soft_Reset Message issued by either Port Partner, that resets counters, timers and states, but does not change the Negotiate voltage and current or the Port's role (e.g., Sink, DFP/UFP, VCONN Source) and does not cause an exit from Modal Operation.  Serious errors are handled by Hard Reset Signaling issued by either Port Partner. A Hard Reset:  resets protocol as for a Soft Reset but also returns the power supply to USB Default Operation (vSafe0V or vSafe5V output) in order to protect the Sink.  restores the Port's Data Role to UFP.  when the Sink is the VCONN Source it removes VCONN then the Source Port is restored as the VCONN Source.  causes all Active Modes to be exited such that the Source is no longer in Modal Operation.  After a Hard Reset it is expected that the Port Partner will respond within tTypeCSinkWaitCap. If this does not occur, then two further Hard Resets are carried out before the UFP stays in the PE_SNK_Wait_for_Capabilities state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 65 2.5.3 Cable Plugs  Cable Plugs are powered when VCONN is present but are not aware of the status of the Contract between the ports the cable assembly is connecting.  Cable Plugs do not initiate AMSs and only respond to Messages sent to them.  Detach or Communications Failure:  Communications can be interrupted at any time.  There is no communication timeout scheme between the DFP/UFP and Cable Plug.  The Cable Plug is ready to respond to potentially repeated requests.  Error handling:  The Cable Plug detects Hard Reset Signaling to determine that the Source and Sink have been reset and will need to reset itself (equivalent to a power cycle).  The Cable Plug cannot generate Hard Reset Signaling itself.  The Hard Reset process power cycles both VBUS and VCONN so this is expected to reset the Cable Plugs by itself.  A Cable Plug detects Cable Reset Signaling to determine that it will need to reset itself (equivalent to a power cycle). Page 66 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.6 Architectural Overview This logical architecture is not intended to be taken as an implementation architecture. An implementation architecture is, by definition, a part of product definition and is therefore outside of the scope of this specification. This section outlines the high-level logical architecture of USB Power Delivery referenced throughout this specification. In practice various implementation options are possible based on many different possible types of PD devices. PD devices can have many different configurations e.g., USB Communication or non-USB Communication, single versus multiple Ports, dedicated power supplies versus supplies shared on multiple ports, hardware versus software-based implementations etc. The architecture outlined in this section is therefore provided only for reference to indicate the high-level logical model used by the PD specification. This architecture is used to identify the key concepts and to indicate logical blocks and possible links between them. The USB Power Delivery is a Port to Port architecture in which each PD Capable device is made up of several major components.  Figure 2.3, "USB Power Delivery Communications Stack" illustrates the relationship of the layers of the communications stack between a Port Pair. The communications stack consists of:  A Device Policy Manager (see Section 8.2, "Device Policy Manager") that exists in all devices and manages USB Power Delivery resources within the device across one or more Ports based on the device's Local Policy.  A Policy Engine (see Section 8.3, "Policy Engine") that exists in each USB Power Delivery Port implements the Local Policy for that Port.  A Protocol Layer (see Section 6, "Protocol Layer") that enables Messages to be exchanged between a Source Port and a Sink Port.  A PHY Layer (see Section 5, "Physical Layer") that handles transmission and reception of bits on the wire and handles data transmission Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 67 Figure 2.3 USB Power Delivery Communications Stack Additionally, USB Power Delivery devices which can operate as USB devices can communicate over USB (see Figure 2.4, "USB Power Delivery Communication Over USB"). An Optional System Policy Manager (see Chapter 9 and [UCSI]) that resides in the USB Host communicates with the PDUSB Device over USB, via the root Port and potentially manages the individual Port to Port connections over a tree of USB Hubs. The Device Policy Manager interacts with the USB interface in each device to provide and update PD related information in the USB domain. Note: A PD device is not required to have a USB device interface. Protocol Policy Engine Device Policy Manager CC Physical Layer Physical Layer Protocol Policy Engine Device Policy Manager Provider Consumer Page 68 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 2.4 USB Power Delivery Communication Over USB Figure 2.5, "High Level Architecture View" shows the logical blocks between two Attached PD Ports (Port Pair). In addition to the communication stack described above there are also:  For a Provider or Dual-Role Power Device: one or more Sources providing power to one or more Ports.  For a Consumer or Dual-Role Power Device: A Sink consuming power.  A USB-C® Port Control module (see Section4.4 "Cable Type Detection") that detects cable Attach/Detach as defined in [USB Type-C 2.4].  USB Power Delivery uses standard cabling as defined in [USB Type-C 2.4]. System Policy Manager Physical Layer Protocol Policy Engine Device Policy Manager CC PD USB Device USB Host USB Root Hub USB Interface USB Hub USB Hub Physical Layer Protocol Policy Engine Device Policy Manager CC PD USB Device USB Interface Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 69 The Device Policy Manager talks to the communication stack, Source/Sink, and the USB-C® Port Control block to manage the resources in the Provider or Consumer. Figure 2.5, "High Level Architecture View" illustrates a Provider and a Consumer. Dual-Role Power Devices can be constructed by combining the elements of both Provider and Consumer into a single device. Providers can also contain multiple Source Ports each with their own communications stack and USB-C® Port Control. Figure 2.5 High Level Architecture View 2.6.1 Policy There are two levels of Policy: 1) System Policy applied system wide by the System Policy Manager across multiple Providers or Consumers. 3) Local Policy enforced on a Provider or Consumer by the Device Policy Manager for a device. Policy comprises several logical blocks:  System Policy Manager (system wide).  Device Policy Manager (one per Provider or Consumer).  Policy Engine (one per Source Port or Sink Port). 2.6.1.1 System Policy Manager Since the USB Power Delivery protocol is Port to Port, implementation of a System Policy requires communication by an additional data communication mechanism i.e., USB. [UCSI]has been created to define an interface for the System Policy Manager to communicate with the Device Policy Manager. When present, the System Policy Manager monitors and controls System Policy between various Providers and Consumers connected via USB. The System Policy Manager resides in the USB Host and communicates via USB with the Device Policy Manager in each connected Device. Devices without USB Communication capability or are not data connected, will not be able to participate in System Policy. The System Policy Manager is Optional so USB Power Delivery Providers and Consumers will operate without it being present. This includes systems where the USB Host does not provide a System Policy Manager and can also include "headless" systems without any USB Host. In those cases where a USB Host is not present, USB Power Delivery is useful for charging purposes, or the powering of devices since useful USB functionality is not possible. Where there is a USB Host, but no System Policy Manager, Providers and Consumers can Negotiate power between Power Source(s) Physical Layer Protocol Source Port Device Policy Manager Provider Policy Engine Power Sink Physical Layer Protocol Sink Port Device Policy Manager Consumer Policy Engine USB-C Port Control USB-C Port Control VBUS USB Port VBUS USB Port CC CC BMC BMC CC VBUS Page 70 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 themselves, independently of USB power rules, but are more limited in terms of the options available for managing power. 2.6.1.2 Device Policy Manager The Device Policy Manager provides mechanisms to monitor and control the USB Power Delivery system within a particular Consumer or Provider. The Device Policy Manager enables Local Policy to be enforced across the system by communication with the System Policy Manager. Local Policy is enacted on a per Port basis by the Device Policy Manager's control of the Source Ports/Sink Ports and by communication with the Policy Engine and USB-C® Port Control for that Port. The Device Policy Manager is responsible for the sharing algorithm used in Shared Capacity Chargers (see [USB Type-C 2.4]) 2.6.1.3 Policy Engine Providers and Consumers are free to implement their own Local Policy on their directly connected Source Ports or Sink Ports. These will be supported by Negotiation and status mechanisms implemented by the Policy Engine for that Port. The Policy Engine interacts directly with the Device Policy Manager to determine the present Local Policy to be enforced. The Device Policy Manager will also inform the Policy Engine whenever there is a change in Local Policy (e.g., Capabilities change). 2.6.2 Message Formation and Transmission 2.6.2.1 Protocol Layer The Protocol Layer forms the Messages used to communicate information between a Port Pair. It is responsible for forming Capabilities Messages, requests and acknowledgments. Additionally, it forms Messages used to swap roles and maintain presence. It receives inputs from the Policy Engine indicating which Messages to send and indicates the responses back to the Policy Engine. The basic protocol uses a push model where the Provider pushes its Capabilities to the Consumer that in turn responds with a request based on the offering. However, the Consumer can asynchronously request the Provider's present Capabilities and can select another voltage/current. Extended Messages of up to a Data Size of MaxExtendedMsgLen can be sent and received provided the Protocol Layer determines that both Port Partners support this capability. When one of both Port Partners do not support Extended Messages of Data Size greater than MaxExtendedMsgLegacyLen then the Protocol Layer supports a Chunking mechanism to break larger Messages into smaller Chunks of size MaxExtendedMsgChunkLen. All Ports that support Extended Messages longer than MaxExtendedMsgLegacyLen are required to support Chunking. 2.6.2.2 PHY Layer The PHY Layer is responsible for sending and receiving Messages across the USB Type-C CC wire and for managing data. PD is a Multi-Drop system, sharing CC between the Port Partners and the Cable Plug(s) that implements Collision Avoidance and recovery mechanisms. The PHY Layer detects errors in the Messages using a CRC. 2.6.3 Collision Avoidance 2.6.3.1 Policy Engine The Policy Engine in a Source will indicate to the Protocol Layer the start and end of each Atomic Message Sequence (AMS) that the Source initiates. The Policy Engine in a Sink will indicate to the Protocol Layer the start of each AMS the Sink initiates. This enables co-ordination of AMS initiation between the Port Partners. 2.6.3.2 Protocol Layer The Protocol Layer in the Source will request the PHY to set the Rp value to SinkTxOK when it is not actively sending Messages. This indicates to the Sink that it can initiate an AMS by sending the first Message in the sequence. The Protocol Layer in the Source will request the PHY Layer to set the Rp value to SinkTxNG to indicate that the Sink cannot initiate an AMS since the Source is about to initiate an AMS. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 71 The Protocol Layer in the Sink, when the Policy Engine indicates that an AMS is being initiated, will wait for the Rp value to be set to SinkTxOK before initiating the AMS by sending the first Message in the sequence. 2.6.3.3 PHY Layer The PHY Layer in the Source will set the Rp value to either SinkTxOK or SinkTxNG as directed by the Protocol Layer. The PHY Layer in the Sink will detect the present Rp value and inform the Protocol Layer. 2.6.4 Power supply 2.6.4.1 Source Each Provider will contain one or more power sources that are shared between one or more Ports. These power sources are controlled by the Local Policy. Source Ports start up in USB Type-C Operation where the Port applies vSafe0V on VBUS and returns to this state on Detach or after a Hard Reset. When the Source detects Attach events it transitions its output to vSafe5V. 2.6.4.2 Sink Consumers are assumed to have one Sink connected to a Port. This Sink is controlled by Local Policy. Sinks start up in USB Default Operation where the Port can operate at vSafe5V with USB default specified current levels and return to this state on Detach or after a Hard Reset. 2.6.4.3 Dual-Role Power Ports Dual-Role Power Ports have the ability to operate as either a Source or a Sink and to swap between the two Power Roles using Power Role Swap or Fast Role Swap. 2.6.4.4 Dead Battery or Lost Power Detection [USB Type-C 2.4] defines mechanisms intended to communicate with and to charge a Sink or DRP with a Dead Battery. 2.6.4.5 VCONN Source The Source Port at Attach, is also the VCONN Source. The responsibility for sourcing VCONN can be swapped between the Source Ports and Sink Ports in a make before break fashion to ensure that the Cable Plugs are continuously powered. To ensure reliable communication with the Cable Plugs only the Port that is the VCONN Source is permitted to communicate with the Cable Plugs. Note: Prior to a Power Role Swap, Data Role Swap or Fast Role Swap each new Source Port needs to ensure that it is the VCONN Source if it needs to communicate with the Cable Plugs after the swap. 2.6.5 DFP/UFP 2.6.5.1 Downstream Facing Port (DFP) The Downstream Facing Port or DFP is equivalent in the USB topology to the Port a USB Device is Attached to. The DFP will also correspond to the USB Host but only if USB Communication is supported while acting as a DFP. Products such as Chargers can be a DFP while not having USB Communication capability. Only the DFP is allowed to control Alternate Mode operation. 2.6.5.2 Upstream Facing Port (UFP) The Upstream Facing Port or UFP is equivalent in the USB topology to the Port on a USB Device that is connected to the USB Host or USB Hub's DFP. The UFP will also correspond to the USB Device but only if USB Communication is supported while acting as a UFP. Products which charge can be a UFP while not having USB Communication capability. Page 72 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.6.5.3 Dual-Role Data Ports Dual-Role Data Ports have the ability to operate as either a DFP or a UFP and to swap between the two Data Roles using Data Role Swap. Note: Products can be Dual-Role Data Ports without being Dual-Role Power Ports that is they can switch logically between DFP and UFP Data Roles even if they are Source-only or Sink-only Ports. 2.6.6 Cable and Connectors The USB Power Delivery specification assumes certified USB cables and associated detection mechanisms as defined in the [USB Type-C 2.4] specification. 2.6.6.1 USB-C Port Control The USB-C® Port Control block provides mechanisms to:  Inform the Device Policy Manager of cable Attach/Detach events.  Inform Sink's Device Policy Manager of the Rp value.  Allow Source's Device Policy Manager to set the Rp value. 2.6.7 Interactions between Non-PD, BC, and PD devices USB Power Delivery only operates when two USB Power Delivery devices are directly connected. When a device finds itself a mixed environment, where the other device does not support the USB Power Delivery Specification, the existing rules on supplying vSafe5V as defined in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications are applied. There are two primary cases to consider:  The USB Host (DFP/Source) is non-PD and as such will not send any Advertisements. An Attached PD Capable device will not see any Advertisements and operates using the rules defined in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications.  The Device (UFP/Sink) is non-PD and as such will not see any Advertisements and therefore will not respond. The USB Host (DFP/Source) will continue to supply vSafe5V to VBUS as specified in the [USB 2.0], [USB 3.2], [USBBC 1.2] or [USB Type-C 2.4] specifications. 2.6.8 Power Rules Power Rules define voltages and current ranges that are offered by compliant USB Power Delivery Sources and used by a USB Power Delivery Sink for a given value of PDP Rating. See Chapter 10 "Power Rules" for further details. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 73 2.7 Extended Power Range (EPR) Operation Extended Power Range is a Mode that provides for up to 240W which is considerably more power than the 100W the original PD specification (SPR Mode) offered. It is a Mode of operation that can be entered only when an Explicit Contract is in place and both the Ports and the Cable Plug(s) support EPR. Entry into EPR Mode follows a strict process; this assures that the higher voltages, at power levels above 100W, are only transferred between known EPR Capable Sources and EPR Capable Sinks over EPR Capable cables. EPR Sources are capable of both Fixed Supply and Adjustable Voltage Supply (AVS) operation. Maintaining EPR Mode operation also requires maintaining a regular cadence of USB PD communications; loss of communications between the EPR Source and EPR Sink will cause a Hard Reset to be initiated resulting in a return to SPR operation. The EPR Mode entry, operational and exit process is summarized by the following steps: 1) Negotiate and enter into an Explicit Contract in the Standard Power Range. During this step, EPR Capable Sources and Sinks will declare their supported EPR Capabilities through PDO/APDO and RDO exchanges. 2) An EPR Sink, having discovered an EPR Source, can request EPR Mode entry. 3) The EPR Source, having already confirmed that the Attached cable assembly is EPR Capable during the First Explicit Contract Negotiation, will respond to the EPR Sink with an acknowledgment of the EPR Mode entry request. 4) While in EPR Mode: a) The EPR Source sends EPR Capabilities (Fixed Supply PDOs and an AVS APDO) to the EPR Sink which requires the Sink to evaluate and respond as appropriate to adjust the Explicit Contract. b) The EPR Sink maintains a regular cadence of communications with the EPR Source to allow EPR Mode to continue. 5) When either the EPR Source or EPR Sink no longer wants to remain in EPR Mode operation, a normal exit from EPR Mode will first require adjusting the Explicit Contract to a voltage of 20V or lower (SPR (A)PDO) followed by an explicit EPR Mode exit request. a) Source initiated: EPR Source sends an EPR_Source_Capabilities Message that only includes SPR voltages to force the EPR Sink to drop to 20V or below followed by the EPR Mode exit. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. b) Sink initiated; EPR Sink requests a drop to 20V or below followed by the EPR Mode exit. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. Figure 2.6, "Example of a Normal EPR Mode Operational Flow" illustrates an example of a normal EPR Mode operational flow. In this example, at some time during the EPR Mode operation, the Source decides that it needs to exit EPR Mode, so it resends the EPR Capabilities to the Sink with only SPR (A)PDOs to cause the Sink to Negotiate an SPR Contract of 20V or lower and then the Source follows with an EPR Mode exit Message. Once EPR Mode is exited, a new SPR Contract is Negotiated to return to SPR Mode operation. Page 74 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 2.6 Example of a Normal EPR Mode Operational Flow Not illustrated in Figure 2.6, "Example of a Normal EPR Mode Operational Flow", while in EPR Mode operation, the Sink might decide it wants to exit EPR Mode. In this case, the Sink must initiate the exit process by revising its Explicit Contract with the Source at 20V or less followed with an EPR_Mode exit Message. Once EPR Mode is exited, a new SPR Contract is Negotiated to formalize the return to SPR Mode operation. Failure to revise the Explicit Contract to one at 20V or less before attempting to exit EPR Mode will result in a Hard Reset. EPR Source EPR Cable EPR Sink Enter EPR Mode? Cable is EPR? Exit EPR Mode? Establish SPR Contract (Source/Sink EPR Status) Request EPR Mode Accept EPR Mode Establish EPR Contract Maintain PD Repetitive Communications Establish EPR Contract (20V or less) Exit EPR Mode Establish SPR Contract (Source/Sink EPR Status) EPR Mode Entry Phase EPR Mode Operation EPR Mode Exit Phase Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 75 2.8 Charging Models This section provides a charging model overview for each of the primary power delivery methods: Fixed Supply, Programmable Power Supply and Adjustable Voltage Supply. 2.8.1 Fixed Supply Charging Models USB Power Delivery supports Fixed Supply charging using a set of defined standard voltages with current available up to the limit of the Source's and cable's Advertised Capabilities. As summarized in Table 2.1, "Fixed Supply Power Ranges", the standard voltages are available in either the Standard Power Range (SPR) and/or the Extended Power Range (EPR). 2.8.2 Programmable Power Supply (PPS) Charging Models USB Power Delivery includes support for Programmable Power Supply (PPS) charging using a set of defined standard voltage ranges. With current up to the limit of the Source's and cable's Advertised Capabilities. Additionally, when operating in SPR Mode the current is also limited by the Operating Current field value in the Request Message. Note: PPS operation is not available in EPR Mode. The standard voltage ranges available in the Standard Power Range (SPR) for PPS are summarized in Table 2.2, "PPS Voltage Power Ranges". Table 2.1 Fixed Supply Power Ranges Power Range Available Current and Voltages PDP Range Notes Standard Power Range (SPR) 3A: 5V, 9V, 15V, 20V 5A1: 20V 15 – 60W >60 – 100W Extended Power Range (EPR) 3A2: 5V, 9V, 15V, 20V 5A2: 20V 5A2: 28V, 36V, 48V 15 – 60W >60 – 100W >100 – 240W Requires entry into EPR Mode. 1) Requires 5A cable. 2) Requires EPR cable. Table 2.2 PPS Voltage Power Ranges Available Current Prog Min Voltage (V) Max Voltage (V) PDP Range 3A 9V Prog 5 11 16 – 60W 15V Prog 5 16 20V Prog 5 21 5A1 20V Prog 5 21 61 – 100W 1) Requires 5A cable. Page 76 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 2.8.3 Adjustable Voltage Supply (AVS) Charging Models USB Power Delivery operating in SPR Mode (when PDP is higher than 27W) and EPR Mode includes support for Adjustable Voltage Supply (AVS) charging using a set of defined standard voltage ranges based on the Source's PDP Rating. The standard voltage ranges available for AVS are summarized in Table 2.3, "AVS Voltage Power Ranges". Table 2.3 AVS Voltage Power Ranges PDP Minimum Voltage (V) Maximum Voltage (V) Maximum Available Current3 Minimum Voltage (V) Maximum Voltage (V) Maximum Available Current >27…45W 9 15 3A N/A >45…60W 9 20 3A >60…100W 9 20 5A1 100…140W 9 20 5A2 15 28 5A2 >140…180W 9 20 5A2 15 36 5A2 >180…240W 9 20 5A2 15 48 5A2 1) Requires 5A cable. 2) Requires an EPR Cable. 3) The maximum available SPR AVS current is determined by the maximum available current in the Fixed Supply 15V PDO in the 9 - 15V range and Fixed Supply 20V PDO in the 15 - 20V range. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 77 3 USB Type-A and USB Type-B Cable Assemblies and Connectors This section has been Deprecated. Please refer to [USBPD 2.0] for details of cables and connectors used in scenar- ios utilizing the BFSK Signaling Scheme in conjunction with USB Type-A or USB Type-B connectors. Page 78 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4 Electrical Requirements This chapter covers the platform's electrical requirements for implementing USB Power Delivery. 4.1 Interoperability with other USB Specifications USB Power Delivery May be implemented alongside the [USB 2.0], [USB 3.2], [USB4], [USBBC 1.2] and [USB Type- C 2.4] (USB Type-C) specifications. In the case where a Device requests power via [USBBC 1.2] and then the USB Power Delivery Specification, it Shall follow the USB Power Delivery Specification until the Port Pair is Detached or there is a Hard Reset. If the USB Power Delivery connection is lost, the Port Shall return to its default state, see Section 6.8.3, "Hard Reset". 4.2 Dead Battery Detection / Unpowered Port Detection Dead Battery/unpowered operation is when a USB Device needs to provide power to a USB Host under the circumstances where the USB Host:  Has a Dead Battery that requires charging or  Has lost its power source or  Does not have a power source or  Does not want to provide power. Dead Battery charging operation for connections between USB Type-C connectors is defined in [USB Type-C 2.4]. 4.3 Cable IR Ground Drop (IR Drop) Every PD Sink Port capable of USB Communication can be susceptible to unreliable USB Communication if the voltage drop across ground falls outside of the acceptable common mode range for the USB Hi-Speed transceivers data lines due to excessive current draw. Certified USB cabling is specified such that such errors don't typically occur (See [USB Type-C 2.4]). 4.4 Cable Type Detection Standard USB Type-C® cable assemblies are rated for PD voltages higher than vSafe5V and current levels of at least 3A (See [USB Type-C 2.4]). The Source Shall limit maximum Capabilities it offers so as not to exceed the Capabilities of the type of cabling detected. Sources capable of offering more than 3A Shall detect the type of Attached cable and limit the Capabilities they offer based on the current carrying capability of the cable determined by the Cable Capabilities determined using the Discover Identity Command (see Section 6.4.4.3.1, "Discover Identity") sent using SOP’ Communication (see Section 2.4, "SOP* Communication") to the Cable Plug. The Cable VDO returned as part of the Discover Identity Command details the maximum current and voltage values that Shall be Negotiated for a given cable as part of an Explicit Contract. The Cable Discovery process is usually run when the Source is powered up, after a Power Role Swap or Fast Role Swap or when power is applied to a Sink. The method used to detect these events Shall meet the following requirements:  Sources Shall run the Cable Discovery process prior to the Source sending Source_Capabilities Messag- es offering currents in excess of 3A and/or voltages in excess of 20V.  Sinks with USB Type-C connectors Shall select Capabilities from the offered Source Capabilities assum- ing that the Source has already determined the Capabilities of the cable.  Sinks with the Dual-Role Power bit set, Shall respond to a Get_Source_Cap Message by declaring their full Source Capabilities, without limiting them based on the cable's Capabilities. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 79 5 Physical Layer 5.1 Physical Layer Overview The Physical Layer (PHY Layer) defines the Signaling technology for USB Power Delivery. This chapter defines the electrical requirements and parameters of the PHY Layer required for interoperability between PDUSB Devices. 5.2 Physical Layer Functions The USB PD PHY Layer consists of a pair of transmitters and receivers that communicate across a single signal wire (CC). All communication is half duplex. The PHY Layer practices Collision Avoidance to minimize communication errors on the channel. The transmitter performs the following functions:  Receive Packet data from the Protocol Layer.  Calculate and append a CRC.  Encode the Packet data including the CRC (i.e., the Payload).  Transmit the Packet (Preamble, SOP*, Payload, CRC and EOP) across the channel using Bi-phase Mark Coding (BMC) over CC. The receiver performs the following functions:  Recover the clock and lock onto the Packet from the Preamble.  Detect the SOP*.  Decode the received data including the CRC.  Detect the EOP and validate the CRC:  If the CRC is Valid, deliver the Packet data to the Protocol Layer.  If the CRC is Invalid, flush the received data. Page 80 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.3 Symbol Encoding Except for the Preamble, all communications on the line Shall be encoded with a line code to ensure a reasonable level of DC-balance and a suitable number of transitions. This encoding makes receiver design less complicated and allows for more variations in the receiver design. 4b5b line code Shall be used. This encodes 4-bit data to 5-bit symbols for transmission and decodes 5-bit symbols to 4-bit data for consumption by the receiver. The 4b5b code provides data encoding along with special symbols. Special symbols are used to signal Hard Reset, and delineate Packet boundaries (see Table 5.1, "4b5b Symbol Encoding"). Table 5.1 4b5b Symbol Encoding Name 4b 5b Symbol Description 0 0000 11110 hex data 0 1 0001 01001 hex data 1 2 0010 10100 hex data 2 3 0011 10101 hex data 3 4 0100 01010 hex data 4 5 0101 01011 hex data 5 6 0110 01110 hex data 6 7 0111 01111 hex data 7 8 1000 10010 hex data 8 9 1001 10011 hex data 9 A 1010 10110 hex data A B 1011 10111 hex data B C 1100 11010 hex data C D 1101 11011 hex data D E 1110 11100 hex data E F 1111 11101 hex data F Sync-1 K-code 11000 Startsynch #1 Sync-2 K-code 10001 Startsynch #2 RST-1 K-code 00111 Hard Reset #1 RST-2 K-code 11001 Hard Reset #2 EOP K-code 01101 EOP End of Packet Error 00000 Shall Not be used Error 00001 Shall Not be used Error 00010 Shall Not be used Error 00011 Shall Not be used Error 00100 Shall Not be used Error 00101 Shall Not be used Sync-3 K-code 00110 Startsynch #3 Error 01000 Shall Not be used Error 01100 Shall Not be used Error 10000 Shall Not be used Error 11111 Shall Not be used Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 81 5.4 Ordered Sets Ordered sets Shall be interpreted according to Figure 5.1, "Interpretation of ordered sets". An ordered set consists of 4 K-codes sent as shown in Figure 5.1, "Interpretation of ordered sets". Figure 5.1 Interpretation of ordered sets A list of the ordered sets used by USB Power Delivery can be seen in Table 5.2, "Ordered Sets". SOP* is a generic term used in place of SOP/SOP’/SOP’’. The receiver Shall search for all four K-codes. When the receiver finds all four K-codes in the correct place, it Shall interpret this as a Valid ordered set. When the receiver finds three out of four K-codes in the correct place, it May Table 5.2 Ordered Sets Ordered Set Reference Cable Reset Section 5.6.5, "Cable Reset" Hard Reset Section 5.6.4, "Hard Reset" SOP Section 5.6.1.2.1, "Start of Packet Sequence (SOP)" SOP’ Section 5.6.1.2.2, "Start of Packet Sequence Prime (SOP')" SOP’_Debug Section 5.6.1.2.4, "Start of Packet Sequence Prime Debug (SOP'_Debug)" SOP’’ Section 5.6.1.2.3, "Start of Packet Sequence Double Prime (SOP'')" SOP’’_Debug Section 5.6.1.2.5, "Start of Packet Sequence Double Prime Debug (SOP''_Debug)" K-code 4 K-code 3 K-code 2 K-code 1 Transmit last Transmit first Transmit last Transmit first b4 b0 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 Page 82 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 interpret this as a Valid ordered set. The receiver Should ensure that all four K-codes are Valid to avoid ambiguity in detection (see Table 5.3, "Validation of Ordered Sets"). Table 5.3 Validation of Ordered Sets 1st code 2nd code 3rd code 4th code Valid1 Corrupt K-code K-code K-code Valid1 K-code Corrupt K-code K-code Valid1 K-code K-code Corrupt K-code Valid1 K-code K-code K-code Corrupt Valid2 (perfect) K-code K-code K-code K-code Invalid (example) K-code Corrupt K-code Corrupt 1) May be interpreted as a Valid ordered set. 2) Shall be interpreted as a Validordered set. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 83 5.5 Transmitted Bit Ordering This section describes the order of bits on the wire that Shall be used when transmitting data of varying sizes. Table 5.4, "Data Size" shows the different data sizes that are possible. Figure 5.2, "Transmit Order for Various Sizes of Data" shows the transmission order that Shall be followed. Figure 5.2 Transmit Order for Various Sizes of Data Table 5.4 Data Size Unencoded Encoded Byte 8-bits 10-bits Word 16-bits 20- bits DWord 32-bits 40-bits b31 b0 b31 Transmit last b16 b15 Transmit first b0 b15 b8 b7 b0 b7 b4 b3 b0 b4 b0 4b5b Transmit last Transmit first BIT 3 BIT 2 BIT 1 BIT 0 BIT 4 Page 84 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6 Packet Format The Packet format Shall consist of a Preamble, an SOP*, (see Section 5.6.1.2, "Start of Packet Sequences"), Packet data including the Message Header, a CRC and an EOP (see Section 5.6.1.5, "End of Packet (EOP)"). The Packet format is shown in Figure 5.3, "USB Power Delivery Packet Format" and indicates which parts of the Packet Shall be 4b/5b encoded. Once 4b/5b encoded, the entire Packet Shall be transmitted using BMC over CC. Note: All the bits in the Packet, including the Preamble, are BMC encoded. See Section 6.2.1, "Message Construction" for more details of the Packet construction for Control Messages, Data Messages and Extended Messages. Figure 5.3 USB Power Delivery Packet Format 5.6.1 Packet Framing The transmission starts with a Preamble that is used to allow the receiver to lock onto the carrier. It is followed by a SOP* (Start of Packet). The Packet is terminated with an EOP (End of Packet) K-code. 5.6.1.1 Preamble The Preamble is used to achieve lock in the receiver by presenting an alternating series of "0s" and "1s", so the average frequency is the carrier frequency. Unlike the rest of the Packet, the Preamble Shall Not be 4b/5b encoded. The Preamble Shall consist of a 64-bit sequence of alternating 0s and 1s. The Preamble Shall start with a "0" and Shall end with a "1". 5.6.1.2 Start of Packet Sequences 5.6.1.2.1 Start of Packet Sequence (SOP) SOP is an ordered set. The SOP ordered set is defined as: three Sync-1 K-codes followed by one Sync-2 K-code (see Table 5.5, "SOP Ordered Set"). A Power Delivery Capable Source or Sink Shall be able to detect and communicate with Packets using SOP. If a Valid SOP is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. Sending and receiving of SOP Packets Shall be limited to PD Capable Ports on PDUSB Hosts and PDUSB Devices. Cable Plugs and VPDs Shall neither send nor receive SOP Packets. Table 5.5 SOP Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-1 3 Sync-1 4 Sync-2 Preamble(training for receiver) SOP* (Start Of Packet) Message Header Byte 0 Byte 1 ... ... Byte n-1 Byte n CRC EOP (End Of Packet) LEGEND: Training sequence provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Provided by the Protocol layer, encoded with 4b5b Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 85 Note: PDUSB Devices, even if they have the physical form of a cable (e.g., AMAs), are still required to respond to SOP Packets. 5.6.1.2.2 Start of Packet Sequence Prime (SOP') The SOP’ ordered set is defined as: two Sync-1 K-codes followed by two Sync-3 K-codes (see Table 5.6, "SOP’ Ordered Set"). A VPD Shall have SOP’ Communication capability. A VPD and a Cable Plug capable of SOP’ Communications Shall only detect and communicate with Packets starting with SOP’. A Port needing to communicate with a Cable Plug capable of SOP’ Communications, Attached between a Port Pair will be able to communicate using both Packets starting with SOP’ to communicate with the Cable Plug and starting with SOP to communicate with its Port Partner. For a VPD or a Cable Plug supporting SOP’ Communications, if a Valid SOP’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. For a Port supporting SOP’ Communications if a Valid SOP or SOP’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. When there is no Explicit Contract or an Implicit Contract in place a Sink Shall Not send SOP’ Packets and Shall Discard all Packets starting with SOP’. 5.6.1.2.3 Start of Packet Sequence Double Prime (SOP'') The SOP’’ ordered set is defined as the following sequence of K-codes: Sync-1, Sync-3, Sync-1, Sync-3 (see Table 5.7, "SOP’’ Ordered Set"). A VPD Shall Not have SOP’’ Communication capability. A Cable Plug capable of SOP’’ Communication, Shall have a SOP’ Communication capability in the other Cable Plug. No cable Shall only support SOP’’ Communication. A Cable Plug to which SOP’’ Communication is assigned Shall only detect and communicate with Packets starting with SOP’’ and Shall Discard any other Packets. A Port needing to communicate with such a Cable Plug, Attached between a Port Pair will be able to communicate using Packets starting with SOP’ and SOP’’ to communicate with the Cable Plugs and Packets starting with SOP to communicate with its Port Partner. A Port which supports SOP’’ Communication Shall also support SOP’ Communication and Shall co-ordinate SOP* Communication so as to avoid collisions. For the Cable Plug supporting SOP’’ Communication, if a Valid SOP’’ is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. For the Port if a Valid SOP* is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. Table 5.6 SOP’ Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-1 3 Sync-3 4 Sync-3 Table 5.7 SOP’’ Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 Sync-3 3 Sync-1 4 Sync-3 Page 86 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6.1.2.4 Start of Packet Sequence Prime Debug (SOP'_Debug) The SOP’_Debug ordered set is defined as the following sequence of K-codes: Sync-1, RST-2, RST-2, Sync-3 (see Table 5.8, "SOP’_Debug Ordered Set"). The usage of this Ordered Set is presently undefined. 5.6.1.2.5 Start of Packet Sequence Double Prime Debug (SOP''_Debug) The SOP’’_Debug ordered set is defined as the following sequence of K-codes: Sync-1, RST-2, Sync-3, Sync-2 (see Table 5.9, "SOP’’_Debug Ordered Set"). The usage of this Ordered Set is presently undefined. 5.6.1.3 Packet Payload The Packet data is delivered from the Protocol Layer (see Section 6.2, "Messages") and Shall be encoded with the hex data codes from Table 5.1, "4b5b Symbol Encoding". 5.6.1.4 CRC The CRC Shall be inserted just after the Payload. It is described in Section 5.6.2, "CRC". 5.6.1.5 End of Packet (EOP) The end of Packet marker Shall be a single EOP K-code as defined in Figure 5.1, "Interpretation of ordered sets". This Shall mark the end of the CRC. After the EOP, the CRC-residual Shall be checked. If the CRC is not good, the whole transmission Shall be Discarded, if it is good, the Packet Shall be delivered to the Protocol Layer. Note: An EOP May be used to prematurely terminate a Packet e.g., before sending Hard Reset Signaling. 5.6.2 CRC The Message Header and data Shall be protected by a 32-bit CRC.  CRC-32 protects the data integrity of the data Payload. CRC-32 is defined as follows:  The CRC-32 polynomial Shall be = 04C1_1DB7h.  The CRC-32 Initial value Shall be = FFFF_FFFFh.  CRC-32 Shall be calculated for all bytes of the Payload not inclusive of any Packet framing symbols (i.e., excludes the Preamble, SOP*, EOP).  CRC-32 calculation Shall begin at byte 0, bit 0 and continue to bit 7 of each of the bytes of the Packet.  The remainder of CRC-32 Shall be complemented.  The residual of CRC-32 Shall be C704 DD7Bh. Table 5.8 SOP’_Debug Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 RST-2 3 RST-2 4 Sync-3 Table 5.9 SOP’’_Debug Ordered Set K-Code Number K-Code in Code Table 1 Sync-1 2 RST-2 3 Sync-3 4 Sync-2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 87 This inversion of the CRC-32 remainder adds an offset of FFFF_FFFFh that will create a constant CRC-32 residual of C704_DD7Bh at the receiver side. Note: The CRC implementation is identical to the one used in [USB 3.2]. Figure 5.4, "CRC-32 Generation" is an illustration of CRC-32 generation. The output bit ordering Shall be as detailed in Table 5.10, "CRC-32 Mapping". Page 88 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.4 CRC-32 Generation The CRC-32 Shall be encoded before transmission. Table 5.10 CRC-32 Mapping CRC-32 Result Bit Position in CRC-32 Field 0 31 1 30 2 29 3 28 4 27 5 26 6 25 7 24 8 23 9 22 10 21 11 20 12 19 13 18 14 17 15 16 16 15 17 14 18 13 19 12 20 11 21 10 22 9 23 8 24 7 25 6 26 5 27 4 28 3 29 2 30 1 31 0 7 6 5 4 3 2 1 0 15 14 13 12 11 10 9 8 23 22 21 20 19 18 17 16 31 30 29 28 27 26 25 24 = Flip Flop 7 6 5 4 3 2 1 0 15141312 1110 9 8 23222120 19181716 31302928 27262524 Data Byte 2 Data Byte 1 Data Byte 0 76543210 Byte Order Bit Order Input 7 B D 1 1 C 4 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 89 5.6.3 Packet Detection Errors CRC errors, or errors detected while decoding encoded symbols using the code table, Shall be treated the same way; the Message Shall be Discarded and a GoodCRC Message Shall Not be returned. While the receiver is processing a Packet, if at any time the CC-line becomes Idle the receiver Shall stop processing the Packet and Discard it (no GoodCRC Message is returned). See Section 5.8.6.1, "Definition of Idle" for the definition of BMC Idle. 5.6.4 Hard Reset Hard Reset Signaling is an ordered set of bytes sent with the purpose to be recognized by the PHY Layer. The Hard Reset Signaling ordered set is defined as: three RST-1 K-codes followed by one RST-2 K-code (see Table 5.11, "Hard Reset Ordered Set"). A device Shall perform a Hard Reset when it receives Hard Reset Signaling. After receiving the Hard Reset Signaling, the device Shall reset as described in Section 6.8.3, "Hard Reset". If a Valid Hard Reset is not detected (see Table 5.3, "Validation of Ordered Sets") then the whole transmission Shall be Discarded. A Cable Plug Shall perform a Hard Reset when it detects Hard Reset Signaling being sent between the Port Partners. After receiving the Hard Reset Signaling, the device Shall reset as described in Section 6.8.3, "Hard Reset". The procedure for sending Hard Reset Signaling Shall be as follows:  If the PHY Layer is currently sending a Message, the Message Shall be interrupted by sending an EOP K- code and the rest of the Message Discarded.  If CC is not Idle, wait for it to become Idle (see Section 5.8.6.1, "Definition of Idle").  Wait tInterFrameGap.  If CC is still Idle send the Preamble followed by the 4 K-codes for Hard Reset Signaling.  Disable the channel (i.e., stop sending and receiving), reset the PHY Layer and inform the Protocol Layer that the PHY Layer has been reset.  Re-enable the channel when requested by the Protocol Layer. Figure 5.5, "Line format of Hard Reset" shows the line format of Hard Reset Signaling which is a Preamble followed by the Hard Reset Ordered Set. Figure 5.5 Line format of Hard Reset Table 5.11 Hard Reset Ordered Set K-Code Number K-Code in Code Table 1 RST-1 2 RST-1 3 RST-1 4 RST-2 Preamble(training for receiver) RST-1 LEGEND: Preamble provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b RST-1 RST-1 RST-2 Page 90 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.6.5 Cable Reset Cable Reset Signaling is an ordered set of bytes sent with the purpose to be recognized by the PHY Layer. The Cable Reset Signaling ordered set is defined as the following sequence of K-codes: RST-1, Sync-1, RST-1, Sync-3 (see Table 5.12, "Cable Reset Ordered Set"). Cable Reset Signaling Shall only be sent by the DFP. The Cable Reset Ordered Set is used to reset the Cable Plugs without the need to Hard Reset the Port Partners. The state of the Cable Plug after the Cable Reset Signaling Shall be equivalent to power cycling the Cable Plug. Figure 5.6, "Line format of Cable Reset" shows the line format of Cable Reset Signaling which is a Preamble followed by the Cable Reset Ordered Set. Figure 5.6 Line format of Cable Reset Table 5.12 Cable Reset Ordered Set K-Code Number K-Code in Code Table 1 RST-1 2 Sync-1 3 RST-1 4 Sync-3 Preamble(training for receiver) RST-1 LEGEND: Preamble provided by the Physical layer, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Sync-1 RST-1 Sync-3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 91 5.7 Collision Avoidance The PHY Layer Shall monitor the channel for data transmission and only initiate transmissions when CC is Idle. If the bus Idle condition is present, it Shall be considered safe to start a transmission provided the conditions detailed in Section 5.8.5.4, "Inter-Frame Gap" are met. The bus Idle condition Shall be checked immediately prior to transmission. If transmission cannot be initiated, then the Packet Shall be Discarded. If the Packet is Discarded because CC is not Idle, the PHY Layer Shall signal to the Protocol Layer that it has Discarded the Message as soon as CC becomes Idle. See Section 5.8.6.1, "Definition of Idle" for the definition of Idle CC. In addition, during an Explicit Contract, the PHY Layer Shall control the Rp resistor value to avoid collisions between Source and Sink transmissions. The Source Shall set an Rp value corresponding to a current of 3A (SinkTxOK) to indicate to the Sink that it May initiate an AMS. The Source Shall set an Rp value corresponding to a current of 1.5A (SinkTxNG) this Shall indicate to the Sink that it Shall Not initiate an AMS and Shall only respond to Messages as part of an AMS. See [USB Type-C 2.4] (USB Type-C) for details of the corresponding Rp values. During the Implicit Contract that precedes an Explicit Contract (including Power Role Swap and Fast Role Swap) the Rp resistor value is used to specify USB Type-C current and is not used for Collision Avoidance. Table 5.13, "Rp values used for Collision Avoidance" details the Rp values that Shall be used by the Source to control Sink initiation of an AMS. See also Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". Table 5.13 Rp values used for Collision Avoidance Source Rp Parameter Description Sink Operation Source Operation 1.5A@5V SinkTxNG Sink Transmit “No Go,” The Sink Shall Not initiate an AMS once tSinkDelay has elapsed after SinkTxNG is asserted. Source can initiate an AMS tSinkTx after setting Rp to this value. 3A@5V SinkTxOK Sink Transmit “Ok” Sink can initiate an AMS. Source cannot initiate an AMS while it has this value set. Page 92 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8 Bi-phase Mark Coding (BMC) Signaling Scheme Bi-phase Mark Coding (BMC) is the PHY Layer Signaling Scheme for carrying USB Power Delivery Messages. This encoding assumes a dedicated DC connection, over the CC wire, which is used for sending PD Messages. Bi-phase Mark Coding is a version of Manchester coding (see [IEC 60958-1]). In BMC, there is a transition at the start of every bit time (UI) and there is a second transition in the middle of the UI when a 1 is transmitted. BMC is effectively DC balanced, (each 1 is DC balanced and two successive zeros are DC balanced, regardless of the number of intervening 1's). It has bounded disparity (limited to 1 bit over an arbitrary Packet, so a very low DC level). Figure 5.7, "BMC Example" illustrates Bi-phase Mark Coding. This example shows the transition from a Preamble to the Sync-1 K-codes of the SOP Ordered Set at the start of a Message. Note: Other K-codes can occur after the Preamble for Signaling such as Hard Reset and Cable Reset. Figure 5.7 BMC Example 5.8.1 Encoding and signaling BMC uses DC coupled baseband Signaling on CC. Figure 5.8, "BMC Transmitter Block Diagram" shows a block diagram for a Transmitter and Figure 5.9, "BMC Receiver Block Diagram" shows a block diagram for the corresponding Receiver. Figure 5.8 BMC Transmitter Block Diagram Preamble Sync-1 Sync-1 0 1 0 1 0 1 0 1 0 1 0 1 0 0 0 0 1 1 Data In BMC to CC Data 4b5b Encoder CRC BMC Encoder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 93 Figure 5.9 BMC Receiver Block Diagram The USB PD baseband signal Shall be driven on the CC wire with a tristate driver that Shall cause a vSwing swing on CC. The tristate driver is slew rate limited (see min rise/fall time in Section 5.8.5, "BMC Transmitter Specifications") to limit coupling to D+/D- and to other signal lines in the USB Type-C fully featured cables (see [USB Type-C 2.4]). This slew rate limiting can be performed either with driver design or an RC filter on the driver output. When sending the Preamble, the transmitter Shall start by transmitting a low level. The receiver Shall tolerate the loss of the first edge. The transmitter May vary the start of the Preamble by tStartDrive min (see Figure 5.10, "BMC Encoded Start of Preamble"). Figure 5.10 BMC Encoded Start of Preamble The transmitter Shall terminate the final bit of the Frame by an edge (the “trailing edge”) to help ensure that the receiver clocks the final bit. If the trailing edge results in the transmitter driving CC low (i.e., the final half-UI of the Frame is high, see Figure 5.11, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition" and Figure 5.12, "Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to- Low Last Transition"), then the transmitter:  Shall continue to drive CC low for tHoldLowBMC.  Should release CC to high impedance as soon as possible after min tHoldLowBMC and Shall release CC by max tEndDriveBMC. Figure 5.11, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition" illustrates the end of a BMC encoded Frame with an encoded zero for which the final bit of the Frame is terminated by a high to low transition. Figure 5.12, "Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to-Low Last Transition" illustrates the end of a BMC Encoded Frame with an encoded one for which the final bit of the Frame is terminated by a high to low transition. Both figures also illustrate the tInterFrameGap timing requirement before the start of the next Frame when the Port has either been transmitting or receiving the previous Frame (see Section 5.8.5.4, "Inter-Frame Gap"). Data from CC 5b4b Decoder CRC BMC Decoder SOP Detect 1UI 1UI 1UI 1UI 1UI 1UI 0 1 0 1 0 1 etc High Impedance (level set by Rp/Rd) tStartDrive Page 94 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.11 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with High-to-Low Last Transition Figure 5.12 Transmitting or Receiving BMC Encoded Frame Terminated by One with High-to-Low Last Transition If the trailing edge results in the transmitter driving CC high (i.e., the final half-UI of the Frame is low, see Figure 5.13, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition" and Figure 5.14, "Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition"), then the transmitter:  Shall continue to drive CC high for 1 UI.  Then Shall drive CC low for tHoldLowBMC.  Should release CC to high impedance as soon as possible after min tHoldLowBMC and Shall release CC by max tEndDriveBMC. Figure 5.13, "Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition" illustrates the ending of a BMC encoded Frame that ends with an encoded zero for which the final bit of the Frame is terminated by a low to high transition. Figure 5.14, "Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition" illustrates the ending of a BMC encoded Frame that ends with an encoded one for which the final bit of the Frame is terminated by a low to high transition. Both figures also illustrate the tInterFrameGap timing requirement before the start of the next Frame when the Port has either been transmitting or receiving the previous Frame (see Section 5.8.5.4, "Inter-Frame Gap"). 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 95 Figure 5.13 Transmitting or Receiving BMC Encoded Frame Terminated by Zero with Low to High Last Transition Figure 5.14 Transmitting or Receiving BMC Encoded Frame Terminated by One with Low to High Last Transition Note: There is no requirement to maintain a timing phase relationship between back-to-back Packets. 1UI 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 0 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) 1UI 1UI max tEndDriveBMC tInterFrameGap min tHoldLowBMC final bit of frame 1 pre-amable for next frame 0 trailing edge of final bit High Impedance (level set by Rp/Rd) Page 96 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.2 Transmit and Receive Masks 5.8.2.1 Transmit Masks The transmitted signal Shall Not violate the masks defined in Figure 5.15, "BMC Tx 'ONE' Mask", Figure 5.16, "BMC Tx 'ZERO' Mask", Table 5.14, "BMC Tx Mask Definition, X Values" and Table 5.15, "BMC Tx Mask Definition, Y Values" at the output of a load equivalent to the cable model and receiver load model described in Section 5.8.3, "Transmitter Load Model". The masks apply to the full range of Rp/Rd values as defined in [USB Type-C 2.4]. Note: The measurement of the transmitter does not need to accommodate a change in signal offset due to the ground offset when current is flowing in the cable. The transmitted signal Shall have a rise time no faster than tRise. The transmitted signal Shall have a fall time no faster than tFall. The maximum limits on the rise and fall times are enforced by the Tx inner masks. Figure 5.15 BMC Tx 'ONE' Mask Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y6 Y7 Y8 Y9 X9 X10 X11 X12 X13 X14 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 97 Figure 5.16 BMC Tx 'ZERO' Mask Table 5.14 BMC Tx Mask Definition, X Values Name Description Value Units X1Tx Left Edge of Mask 0.015 UI X2Tx see figure 0.07 UI X3Tx see figure 0.15 UI X4Tx see figure 0.25 UI X5Tx see figure 0.35 UI X6Tx see figure 0.43 UI X7Tx see figure 0.485 UI X8Tx see figure 0.515 UI X9Tx see figure 0.57 UI X10Tx see figure 0.65 UI X11Tx see figure 0.75 UI X12Tx see figure 0.85 UI X13Tx see figure 0.93 UI X14Tx Right Edge of Mask 0.985 UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y6 Y7 Y8 Y9 X9 X10 X11 X12 X13 X14 Page 98 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.2.2 Receive Masks A Source using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when sourcing power as defined in Figure 5.17, "BMC Rx 'ONE' Mask when Sourcing Power", Figure 5.18, "BMC Rx 'ZERO' Mask when Sourcing Power" and Table 5.16, "BMC Rx Mask Definition". The Source Rx mask is bounded by sweeping a Tx mask compliant signal, with added vNoiseActive between power neutral and Source offsets. A Consumer using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when sinking power as defined in Figure 5.21, "BMC Rx 'ONE' Mask when Sinking Power", Figure 5.22, "BMC Rx 'ZERO' Mask when Sinking Power" and Table 5.16, "BMC Rx Mask Definition". The Consumer Rx mask is bounded by sweeping a Tx mask compliant signal, with added vNoiseActive between power neutral and Consumer offsets. Every product using the BMC Signaling Scheme Shall be capable of receiving a signal that complies with the mask when power neutral as defined in Figure 5.19, "BMC Rx 'ONE' Mask when Power neutral", FFigure 5.20, "BMC Rx 'ZERO' Mask when Power neutral" and Table 5.16, "BMC Rx Mask Definition". Dual-Role Power Devices Shall meet the receiver requirements for a Source when providing power during any transmission using the BMC Signaling Scheme or a Sink when consuming power during any transmission using the BMC Signaling Scheme. Cable Plugs Shall meet the receiver requirements for both a Source and a Sink during any transmission using the BMC Signaling Scheme. The parameters used in the masks are specified to be appropriate to either edge triggered or oversampling receiver implementations. The masks are defined for 'ONE' and 'ZERO' separately as BMC enforces a transition at the midpoint of the unit interval while a 'ONE' is transmitted. The Rx masks are defined to bound the Rx noise after the Rx bandwidth limiting filter with the time constant tRxFilter has been applied. The boundaries of Rx outer mask, Y1Rx and Y5Rx, are specified according to vSwing max and accommodate half of vNoiseActive from cable noise coupling and the signal offset vIRDropGNDC due to the ground offset when current is flowing in the cable. The vertical dimension of the Rx inner mask, Y4Rx - Y2Rx, for power neutral is derived by reducing the vertical dimension of the Tx inner mask, Y7Tx - Y3Tx, at time location X3Tx by vNoiseActive to account for cable noise coupling. The received signal is composed of a waveform compliant to the Tx mask plus vNoiseActive. The vertical dimension of the Rx inner mask for sourcing power is derived by reducing the vertical dimension of the Tx inner mask by vNoiseActive and vIRDropGNDC to account for both cable noise coupling and signal DC offset. Table 5.15 BMC Tx Mask Definition, Y Values Name Description Value Units Y1Tx Lower bound of Out- er mask -0.075 V Y2Tx Lower bound of in- ner mask 0.075 V Y3Tx see figure 0.15 V Y4Tx see figure 0.325 V Y5Tx Inner mask vertical midpoint 0.5625 V Y6Tx see figure 0.8 V Y7Tx see figure 0.975 V Y8Tx see figure 1.04 V Y9Tx Upper Bound of Out- er mask 1.2 V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 99 The received signal is composed of a waveform compliant to the Tx mask plus the maximum value of vNoiseActive plus vIRDropGNDC where the vIRDropGNDC value transitions between the minimum and the maximum values as allowed in this spec. The vertical dimension of the Rx inner mask for sinking power is derived by reducing the vertical dimension of the Tx inner mask by vNoiseActive max and vIRDropGNDC max for account for both cable noise coupling and signal DC offset. The received signal is composed of a waveform compliant to the Tx mask plus the maximum value of vNoiseActive plus vIRDropGNDC where the vIRDropGNDC value transitions between the minimum and the maximum values as allowed in this spec. The center line of the Rx inner mask, Y3Rx, is at half of the nominal vSwing for power neutral, and is shifted up by half of vIRDropGNDC max for sourcing power and is shifted down by half of vIRDropGNDC max for sinking power. The receiver sensitivity Shall be set such that the receiver does not treat noise on an undriven signal path as an incoming signal. Signal amplitudes below vNoiseIdle max Shall be treated as noise when BMC is Idle. Figure 5.17 BMC Rx 'ONE' Mask when Sourcing Power Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Page 100 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.18 BMC Rx 'ZERO' Mask when Sourcing Power Figure 5.19 BMC Rx 'ONE' Mask when Power neutral Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 101 Figure 5.20 BMC Rx 'ZERO' Mask when Power neutral Figure 5.21 BMC Rx 'ONE' Mask when Sinking Power Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Page 102 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 5.22 BMC Rx 'ZERO' Mask when Sinking Power Table 5.16 BMC Rx Mask Definition Name Description Value Units X1Rx Left Edge of Mask 0.07 UI X2Rx Top Edge of Mask 0.15 UI X3Rx See figure 0.35 UI X4Rx See figure 0.43 UI X5Rx See figure 0.57 UI X6Rx See figure 0.65 UI X7Rx See figure 0.85 UI X8Rx See figure 0.93 UI Y1Rx Lower bound of Outer Mask -0.3325 V Y2Rx Lower Bound of Inner Mask Y3Rx – 0.205 when sourcing power1 or sinking power1. Y3Rx – 0.33 when power neutral1. V Y3Rx Center line of Inner Mask 0.6875 Sourcing Power1. 0.5625 Power Neutral1. 0.4375 Sinking Power1. V Y4Rx Upper bound of Inner mask Y3Rx + 0.205 when sourcing power1 or sinking power1. Y3Rx + 0.33 when power neutral1. V Y5Rx Upper bound of the Outer mask 1.5325 V 1) The position of the center line of the Inner Mask is dependent on whether the receiver is Sourcing or Sinking power or is Power Neutral (see earlier in this section). Y5 Y4 Y3 Y2 Y1 X1 X2 X3 X4 X5 X6 X7 X8 0.5UI 1UI Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 103 5.8.3 Transmitter Load Model The transmitter load model Shall be equivalent to the circuit outlined in Figure 5.23, "Transmitter Load Model for BMC Tx from a Source" for a Source and Figure 5.24, "Transmitter Load Model for BMC Tx from a Sink" for a Sink. It is formed by the concatenation of a cable load model and a receiver load model. See [USB Type-C 2.4] for details of the Rp and Rd resistors. Note: The parameters zCable_CC, tCableDelay_CC and cCablePlug_CC are defined in [USB Type-C 2.4]. Figure 5.23 Transmitter Load Model for BMC Tx from a Source Figure 5.24 Transmitter Load Model for BMC Tx from a Sink The transmitter system components rOutput and cShunt are illustrated for Informative purposes, and do not form part of the transmitter load model. See Section 5.8.5, "BMC Transmitter Specifications" for a description of the transmitter system design. The value of the modeled cable inductance, La, (in nH) Shall be calculated from the following formula: La= tCableDelay_CCmax* zCable_CCmin tCableDelay_CC is the modeled signal propagation delay through the cable, and zCable_CC is the modeled cable impedance. The modeled cable inductance is 640nH for a cable with zCable_CCmin = 32Ω and tCableDelay_CCmax = 20ns. The value of the modeled cable capacitance, Ca, (in pF) Shall be calculated from the following formula: Ca=tCableDelay_CCmax/zCable_CCmin The modeled cable capacitance is Ca = 625pF for a cable with zCable_CCmin = 32Ω and tCableDelay_CCmax = 20ns. Therefore, Ca/2 = 312.5pF. cCablePlug_CC models the capacitance of the plug at each end of the cable. cReceiver models the capacitance of the receiver. The maximum values Shall be used in each case. cCablePlug_CC cShunt Connector ca 2 La cReceiver Receiver Load Model Transmitter Load Model Output Cable Model cCablePlug_CC ca 2 rOutput Rp Rd cCablePlug_CC cShunt Connector ca 2 La cReceiver Receiver Load Model Transmitter Load Model Output Cable Model cCablePlug_CC ca 2 rOutput Rp Rd Page 104 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: The transmitter load model assumes that there are no other return currents on the ground path. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 105 5.8.4 BMC Common specifications This section defines the common receiver and transmitter requirements. 5.8.4.1 BMC Common Parameters The electrical requirements specified in Table 5.17, "BMC Common Normative Requirements" Shall apply to both the transmitter and receiver. Table 5.17 BMC Common Normative Requirements Name Description Min Nom Max Units Comment fBitRate Bit rate 270 300 330 Kbps tUnitInterval Unit Interval1 3.03 3.70 µs 1/fBitRate 1) Denotes the time to transmit an unencoded data bit, not the shortest high or low times on the wire after encoding with BMC. A single data bit cell has duration of 1UI, but a data bit cell with value 1 will contain a centrally placed 01 or 10 transition in addition to the transition at the start of the cell. Page 106 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.5 BMC Transmitter Specifications The transmitter Shall meet the specifications defined in Table 5.18, "BMC Transmitter Normative Requirements". Table 5.18 BMC Transmitter Normative Requirements Name Description Min Nom Max Units Comment pBitRate Maximum difference between the bit-rate during the part of the Packet following the Preamble and the reference bit-rate. 0.25 % The reference bit rate is the average bit rate of the last 32 bits of the Preamble. rFRSwapTx Fast Role Swap Request transmit driver resistance (excluding cable resistance) 5 Ω Maximum driver resistance of a Fast Role Swap Request transmitter. Assumes a worst case cable resistance of 15Ω as defined in [USB Type-C 2.4]. Note: Based on this value the maximum combined driver and cable resistance of a Fast Role Swap Request transmitter is 20Ω. tEndDriveBMC Time to cease driving the line after the end of the last bit of the Frame. 23 µs Min value is limited by tHoldLowBMC. tFall Fall Time 300 ns 10% and 90% amplitude points, minimum is under an unloaded condition. tHoldLowBMC Time to cease driving the line after the final high-to-low transition. 1 µs Max value is limited by tEndDriveBMC. tInterFrameGap Time from the end of last bit of a Frame until the start of the first bit of the next Preamble. 25 µs tFRSwapTx Fast Role Swap Request transmit duration 60 120 µs Fast Role Swap Request is indicated from the Initial Source to the Initial Sink by driving CC low for this time. tRise Rise time 300 ns 10% and 90% amplitude points, minimum is under an unloaded condition. tStartDrive Time before the start of the first bit of the Preamble when the transmitter Shall start driving the line. -1 1 µs vSwing Voltage Swing 1.05 1.125 1.2 V Applies to both no load condition and under the load condition specified in Section 5.8.3, "Transmitter Load Model". zDriver Transmitter output impedance 33 75 Ω Source output impedance at the Nyquist frequency of [USB 2.0] low speed (750 kHz) while the Source is driving the CC line. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 107 5.8.5.1 Capacitance when not transmitting cReceiver is the capacitance that a DFP or UFP Shall present on the CC line when the DFP or UFP's receiver is not transmitting on the line. The transmitter May have more capacitance than cReceiver while driving the CC line, but Shall meet the waveform mask requirements. Once transmission is complete, the transmitter Shall disengage capacitance in excess of cReceiver from the CC wire within tInterFrameGap. 5.8.5.2 Source Output Impedance Source output impedance zDriver is determined by the driver resistance and the shunt capacitance of the Source and is hence a frequency dependent term. zDriver impacts the noise ingression in the cable. It is specified such that the noise at the Receiver is bounded. zDriver is defined by the following equation: zDriver=rOutput/(1+s*rOutput*cShunt) Figure 5.25 Transmitter diagram illustrating zDriver cShunt Shall Not cause a violation of cReceiver when not transmitting. 5.8.5.3 Bit Rate Drift Limits on the drift in fBitRate are set to help low-complexity receiver implementations. fBitRate is the reciprocal of the average bit duration from the previous 32 bits at a given portion of the Packet. The change in fBitRate during a Packet Shall be less than pBitRate. The reference bit rate (refBitRate) is the average fBitRate over the last 32 bits of the Preamble. fBitRate throughout the Packet, including the EOP, Shall be within pBitRate of refBitRate. pBitRate is expressed as a percentage: pBitRate = | fBitRate - refBitRate | / refBitRate x 100% The transmitter Shall have the same pBitRate for all Packet types. The BIST Carrier Mode and Bit Stream signals are continuous signals without a Payload. When checking pBitRate any set of 1044 bits (20 bit SOP followed by 1024 PRBS bits) within a continuous signal May be considered as the part of the Packet following the Preamble and the 32 preceding bits considered to be the last 32 bits of the Preamble used to compute refBitRate. rOutput cShunt zDriver Page 108 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.5.4 Inter-Frame Gap Figure 5.26, "Inter-Frame Gap Timings" illustrates the inter-Frame gap timings. Figure 5.26 Inter-Frame Gap Timings The transmitter Shall drive the bus for no longer than tEndDriveBMC after transmitting the final bit of the Frame. Before starting to transmit the next Frame's Preamble the transmitter of the next Frame Shall ensure that it waits for tInterFrameGap after either:  Transmitting the previous Frame, for example sending the next Message in an AMS immediately after having sent a GoodCRC Message, or  Receiving the previous Frame, for example when responding to a received Message with a GoodCRC Message, or  Observing an Idle condition on CC (see Section 5.7, "Collision Avoidance"). In this case the Port is waiting to initiate an AMS observes Idle (see Section 5.8.6.1, "Definition of Idle") and then waits tInterFrameGap before transmitting the Frame. See also Section 5.7, "Collision Avoidance" for details on when an AMS can be initiated. Note: The transmitter is also required to verify a bus Idle condition immediately prior to starting transmission of the next Frame (see Section 5.8.6.1, "Definition of Idle"). The transmitter of the next Frame May vary the start of the Preamble by tStartDrive (see Section 5.8.1, "Encoding and signaling"). See also Section 5.8.1, "Encoding and signaling" for figures detailing the timings relating to transmitting, receiving, and observing Idle in relating to Frames. 5.8.5.5 Shorting of Transmitter Output A Transmitter in a Port or Cable Plug Shall tolerate having its output be shorted to ground for tFRSwapTx max. This is due to the potential for Fast Role Swap to be signaled while the Transmitter is in the process of transmitting (see Section 5.8.5.6, "Fast Role Swap Transmission"). End of Frame Preamble Bus driven after end of Frame Bus driven before Preamble tEndDriveBMC tStartDrive tInterFrameGap Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 109 5.8.5.6 Fast Role Swap Transmission The Fast Role Swap process is intended for use by a PDUSB Hub that presently has an external supply and is providing power both through its downstream Ports to USB Devices and upstream to a USB Host such as a laptop. On removal of the external wall supply Fast Role Swap enables a VBUS supply to be maintained by allowing the USB Host to apply vSafe5V when it sees VBUS droop below vSafe5V after having detected Fast Role Swap Signaling. The Fast Role Swap AMS is then used to correctly assign Source/Sink Power Roles and configure the Rp/Rd resistors (see Section 8.3.2.8, "Fast Role Swap"). The Initial Source Shall signal a Fast Role Swap Request by driving CC to ground with a resistance of less than rFRSwapTx for tFRSwapTx. The Initial Source Shall only send a Fast Role Swap Request when it has an Explicit Contract. The Initial Source May send a Fast Role Swap Request even if it has not yet had its Sink Capabilities queried by the Initial Sink. On transmission of the Fast Role Swap Request any pending Messages Shall be Discarded (see Section 6.12.2.2.1, "Common Protocol Layer Message Transmission State Diagram"). The Fast Role Swap Signaling May override any active transmissions. Since the Initial Sink's response to the Fast Role Swap signal is to send an FR_Swap Message, the Initial Source Shall ensure Rp is set to SinkTxOK once the Fast Role Swap Signaling is complete. Page 110 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.6 BMC Receiver Specifications The receiver Shall meet the specifications defined in Table 5.19, "BMC Receiver Normative Requirements". 5.8.6.1 Definition of Idle BMC Collision Avoidance is performed by the detection of signal transitions at the receiver. Detection is active when nTransitionCount transitions occur at the receiver within a time window of tTransitionWindow. After waiting tTransitionWindow without detecting nTransitionCount transitions the bus Shall be declared Idle. Refer to Section 5.8.5.4, "Inter-Frame Gap" for details of when transmissions May start. Table 5.19 BMC Receiver Normative Requirements Name Description Min Nom Max Units Comment cReceiver CC receiver capacitance 200 600 pF The DFP or UFP system Shall have ca- pacitance within this range when not transmitting on the line. nBER Bit error rate, S/N = 25 dB 10-6 nTransitionCount Transitions for signal detect 3 Number of transitions to be detected to declare bus non-Idle. tFRSwapRx Fast Role Swap Request de- tection time 30 50 µs A Fast Role Swap Request results in the receiver detecting a signal low for at least this amount of time. tRxFilter Rx bandwidth limiting filter (digital or analog) 100 ns Time constant of a single pole filter to limit broad-band noise ingression1. tTransitionWindow Time window for detecting non-Idle 12 20 µs vFRSwapCableTx Fast Role Swap Request volt- age detection threshold 490 520 550 mV The Fast Role Swap Request must be be- low this voltage threshold to be detect- ed. vIRDropGNDC Cable Ground IR Drop 250 mV As specified in [USB Type-C 2.4]. vNoiseActive Noise amplitude when BMC is active. 165 mV Peak-to-peak noise from VBUS, [USB 2.0] and SBU lines after the Rx band- width limiting filter with the time con- stant tRxFilter has been applied. vNoiseIdle Noise amplitude when BMC is Idle. 300 mV Peak-to-peak noise from VBUS, [USB 2.0] and SBU lines after the Rx band- width limiting filter with the time con- stant tRxFilter has been applied. zBmcRx Receiver Input Impedance 1 MΩ 1) Broad-band noise ingression is due to coupling in the cable interconnect. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 111 5.8.6.2 Multi-Drop The BMC Signaling Scheme is suitable for use in Multi-Drop configurations containing one or two BMC Multi-Drop transceivers connected to the CC wire, where one or both ends of a cable contains a Multi-Drop transceiver. In this specification the location of the Multi-Drop transceiver is referred to as the Cable Plug. Figure 5.27, "Example Multi-Drop Configuration showing two DRPs" below illustrates a typical Multi-Drop configuration with two DRPs. Figure 5.27 Example Multi-Drop Configuration showing two DRPs The Multi-Drop transceiver Shall obey all the electrical characteristics specified in this section except for those relating to capacitance. The maximum capacitance allowed for the Multi-Drop node when not driving the line is cCablePlug_CC defined in [USB Type-C 2.4]. There are no constraints as to the distance of the Multi-Drop transceiver from the end of the plug. The Multi-Drop transceiver(s) May be located anywhere along the cable including the plugs. The Multi-Drop transceiver suffers less from ground offset compared to the transceivers in the USB Host or USB Device and contributes no significant reflections. It is possible to have a configuration at Attach where one Port can be a VCONN Source and the other Port is not able to be a VCONN Source, such that there is no switch in the second Port. An example of a DFP with a switch Attached to a UFP without a switch is outlined in Figure 5.28, "Example Multi-Drop Configuration showing a DFP and UFP". The capacitance on the CC line for a Port not able to be a VCONN Source Shall still be within cReceiver except when transmitting. Figure 5.28 Example Multi-Drop Configuration showing a DFP and UFP cReceiver Switch VCONN cCablePlug cCablePlug Connector Connector Cable DRP DRP cReceiver Switch VCONN cReceiver Switch VCONN cCablePlug cCablePlug Connector Connector Cable DFP UFP cReceiver Page 112 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 5.8.6.3 Fast Role Swap Detection An Initial Sink prepares for a Fast Role Swap by ensuring that once it has detected the Fast Role Swap Request its power supply is ready to respond by applying vSafe5V according to the timing detailed in Section 7.1.13, "Fast Role Swap". The Initial Sink Shall only respond to the Fast Role Swap Request when all the following conditions have been met:  An Explicit Contract has been established and the Sink Capabilities of the Initial Source have been received by, and at the request of, the Initial Sink.  The Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap bits set in its 5V Fixed Supply PDO.  The Initial Sink is able and willing to source the current requested by the Initial Source in the Fast Role Swap bits of its Sink_Capabilities Message. On detection of the Fast Role Swap Request any pending Messages Shall be Discarded (see Section 6.12.2.2.1, "Common Protocol Layer Message Transmission State Diagram"). When the Initial Sink is prepared for a Fast Role Swap and the bus is idle the CC voltage averaged over tFRSwapRx min remains above 0.7V (see [USB Type-C 2.4]) since the Source Rp is either 1.5A or 3.0A. However, vNoiseIdle noise May cause the CC line voltage to reach 0.7V-vNoiseIdle/2 for short durations. When the Initial Sink is prepared for a Fast Role Swap while it is transmitting and the Initial Source is sending a Fast Role Swap Request, the transmission will be attenuated such that the peak CC voltage will not exceed vFRSwapCableTx min. Therefore, when the Initial Sink is prepared for a Fast Role Swap, it Shall Not detect a Fast Role Swap Request when the CC voltage, averaged over tFRSwapRx min, is above 0.7V. When the Initial Sink is prepared for a Fast Role Swap, it Shall detect a CC voltage lower than vFRSwapCableTx min for tFRSwapRx as a Fast Role Swap Request. Note: The Initial Sink is not required to average the CC voltage to meet these requirements. The Initial Sink Shall initiate the Fast Role Swap AMS within tFRSwapInit of detecting the Fast Role Swap Request in order to assign the Rp/Rd resistors to the correct Ports and to re-synchronize the state machines (see Section 6.3.19, "FR_Swap Message"). The Initial Sink Shall become the New Source and Shall start supplying vSafe5V at USB Type-C current (see [USB Type-C 2.4]) no later than tSrcFRSwap after VBUS has dropped below vSafe5V. An Initial Sink Shall disable its VBUS Disconnect Threshold detection circuitry while Fast Role Swap detection is active. Note: While power is transitioning the VCONN Source to the Cable Plug(s) cannot be guaranteed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 113 5.9 Built in Self-Test (BIST) The following sections define BIST functionality which Shall be supported. 5.9.1 BIST Carrier Mode In BIST Carrier Mode, the PHY Layer Shall send out a BMC encoded continuous string of alternating "1"s and "0"s. This enables the measurement of power supply noise and frequency drift. Note: This transmission is a purely a sequence of alternating bits and Shall Not be formatted as a Packet. See also Section 6.4.3, "BIST Message". 5.9.2 BIST Test Data Mode A BIST Test Data Message is used by the Tester to send various Tester generated Test Patterns to the UUT in order to test the UUT's receiver. See also Section 6.4.3, "BIST Message". Figure 5.29, "Test Frame" shows the Test Frame which Shall be sent by the Tester to the UUT. The BIST Message, with a BIST Test Data BIST Data Object consists of a Preamble, followed by SOP*, followed by the Message Header with a data length of 7 Data Objects, followed a BIST Test Data BIST Data Object, followed by 6 Data Objects containing test data, followed by the CRC and then an EOP. Figure 5.29 Test Frame Preamble(training for receiver) SOP* (Start Of Packet) Test Data 192 bits ... LEGEND: Preamble, not encoded with 4b5b Provided by the Physical layer, encoded with 4b5b Header Data Objects = 7 BIST Test Data BDO Provided by the Protocol layer, encoded with 4b5b CRC EOP (End Of Packet) ... Page 114 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6 Protocol Layer 6.1 Overview This chapter describes the requirements of the USB Power Delivery Specification's Protocol Layer including:  Details of how Messages are constructed and used.  Use of timers and timeout values.  Use of Message and retry counters.  Reset operation.  Error handling.  State behavior. Refer to Section 2.6, "Architectural Overview" for an overview of the theory of operation of USB Power Delivery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 115 6.2 Messages This specification defines three types of Messages:  Control Messages that are short and used to manage the Message flow between Port Partners or to exchange Messages that require no additional data. Control Messages are 16 bits in length.  Data Messages that are used to exchange information between a pair of Port Partners. Data Messages range from 48 to 240 bits in length.  Some examples of Data Messages are:  Those used to expose Capabilities and Negotiate power.  Those used for the BIST.  Those that are Vendor Defined Messages.  Extended Messages that are used to exchange information between a pair of Port Partners. Extended Messages are up to MaxExtendedMsgLen bytes.  Some examples of Extended Messages are:  Those used for Source and Battery information.  Those used for Security.  Those used for Firmware Update.  Those that are Vendor Defined Extended Messages. 6.2.1 Message Construction All Messages Shall be composed of a Message Header and a variable length (including zero) data portion. A Message either originates in the Protocol Layer and is passed to the PHY Layer, or it is received by the PHY Layer and is passed to the Protocol Layer. Figure 6.1, "USB Power Delivery Packet Format for a Control Message" illustrates a Control Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.1 USB Power Delivery Packet Format for a Control Message Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload" illustrates a Data Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Legend: PHY Layer Protocol Layer Page 116 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.2 USB Power Delivery Packet Format including Data Message Payload Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" illustrates an Extended Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.3 USB Power Delivery Packet Format including an Extended Message Header and Payload 6.2.1.1 Message Header Every Message Shall start with a Message Header as shown in:  Figure 6.1, "USB Power Delivery Packet Format for a Control Message"  Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload"  Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and as defined in Table 6.1, "Message Header". The Message Header contains basic information about the Message and the PD Port Capabilities. The Message Header May be used standalone as a Control Message when the Number of Data Objects field is zero or as the first part of a Data Message when the Number of Data Objects field is non-zero. 6.2.1.1.1 Extended The 1-bit Extended field Shall be set to zero to indicate a Control Message or Data Message and set to one to indicate an Extended Message. Table 6.1 Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Extended Section 6.2.1.1.1 14…12 SOP* Number of Data Objects Section 6.2.1.1.2 11…9 SOP* MessageID Section 6.2.1.1.3 8 SOP only Port Power Role Section 6.2.1.1.4 SOP’/SOP’’ Cable Plug Section 6.2.1.1.7 7…6 SOP* Specification Revision Section 6.2.1.1.5 5 SOP only Port Data Role Section 6.2.1.1.6 SOP’/SOP’’ Reserved Section 1.4.2 4…0 SOP* Message Type Section 6.2.1.1.8 Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) 0..7 Data Object(s) Legend: PHY Layer Protocol Layer Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Data (0..260 bytes) Legend: PHY Layer Protocol Layer Extended Message Header (16 bit) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 117 The Extended field Shall apply to all SOP* Packet types. 6.2.1.1.2 Number of Data Objects When the Extended field is set to zero the 3-bit Number of Data Objects field Shall indicate the number of 32-bit Data Objects that follow the Message Header. When this field is zero the Message is a Control Message and when it is non-zero, the Message is a Data Message. The Number of Data Objects field Shall apply to all SOP* Packet types. When both the Extended bit and Chunked bit are set to one, the Number of Data Objects field Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. When the Extended bit is set to one and Chunked bit is set to zero, the Number of Data Objects field Shall be Reserved. Note: In this case, the Message length is determined solely by the Data Size field in the Extended Message Header. 6.2.1.1.3 MessageID The 3-bit MessageID field is the value generated by a rolling counter maintained by the originator of the Message. The MessageIDCounter Shall be initialized to zero at power-on as a result of a Soft Reset, or a Hard Reset. The MessageIDCounter Shall be incremented when a Message is successfully received as indicated by receipt of a GoodCRC Message. Note: The usage of MessageID during testing with BIST Messages is defined in [USBPDCompliance]. The MessageID field Shall apply to all SOP* Packet types. 6.2.1.1.4 Port Power Role The 1-bit Port Power Role field Shall indicate the Port's present Power Role:  0b Sink  1b Source Messages, such as Get_Sink_Cap_Extended, that are only ever sent by a Source, Shall always have the Port Power Role field set to Source. Similarly, Messages such as the Request Message that are only ever sent by a Sink Shall always have the Port Power Role field set to Sink. During the Power Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that the Initial Source's power supply is turned off (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Power Role Swap AMS, for the Initial Sink, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that VBUS is not being driven by the Initial Source and is within vSafe5V (see Figure 8.39, "Successful Fast Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Sink Port, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Figure 8.39, "Successful Fast Role Swap Sequence"). Note: The GoodCRC Message sent by the Initial Sink in response to the PS_RDY Message from the Initial Source will have its Port Power Role field set to Sink since this is initiated by the Protocol Layer. Subsequent Page 118 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Messages initiated by the Policy Engine, such as the PS_RDY Message sent to indicate that VBUS is ready, will have the Port Power Role field set to Source. The Port Power Role field of a received Message Shall Not be verified by the receiver and Shall Not lead to Soft Reset, Hard Reset or Error Recovery if it is incorrect. The Port Power Role field Shall only be defined for SOP Packets. 6.2.1.1.5 Specification Revision The Specification Revision field Shall be one of the following values (except 11b):  00b - Revision 1.0 (Deprecated)  01b - Revision 2.0  10b - Revision 3.x  11b - Reserved, Shall Not be used. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every PD Specification Revision starting from [USB 2.0] for SOP*; the only exception to this is a VPD which Shall Ignore Messages sent with PD Specification Revision 2.0 and earlier. After a physical or logical (USB Type-C® Error Recovery) Attach, a Port discovers the common Specification Revision level between itself and its Port Partner and/or the Cable Plug(s), and uses this Specification Revision level until a Detach, Hard Reset or Error Recovery happens. After detection of the Specification Revision to be used, all PD communications Shall comply completely with the relevant Revision of the PD specification. The 2-bit Specification Revision field of a GoodCRC Message does not carry any meaning and Shall be considered as don't care by the recipient of the Message. The sender of a GoodCRC Message Shall set the Specification Revision field to 01b (Revision 2.0) when responding to a Message that contains 01b in the Specification Revision field of the Message Header. The sender of a GoodCRC Message May set the Specification Revision field to 01b or 10b when responding to a Message that contains 10b (Revision 3.x) in the Specification Revision field of the Message Header. The Specification Revision field Shall apply to all SOP* Packet types. An Attach event or a Hard Reset Shall cause the detection of the applicable Specification Revision to be performed for both Ports and Cable Plugs according to the rules stated below: When the Source Port first communicates with the Sink Port the Specification Revision field Shall be used as described by the following steps: 1) The Source Port sends a Source_Capabilities Message to the Sink Port setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Source Port supports. 2) The Sink Port responds with a Request Message setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Sink Port supports that is equal to or lower than the Specification Revision received from the Source Port. 3) The Source and Sink Ports Shall use the Specification Revision in the Request Message from the Sink in step 2 in all subsequent communications until a Detach, Hard Reset, or Error Recovery happens. Prior to entering the First Explicit Contract, the VCONN Source Shall use the following steps to establish a Specification Revision level: 1) The VCONN Source sends a Discover Identity REQ to the Cable Plug (SOP’) setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports. After a VCONN Swap the required Soft_Reset / Accept Message exchange is used for the same purpose (see Section 6.3.13, "Soft Reset Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 119 2) The Cable Plug responds with a Discover Identity ACK setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports that is equal to or lower than the Specification Revision it received from the Source Port. 3) The Cable Plug and VCONN Source Shall communicate using the lower of the two revisions until an Explicit Contract has been established. 4) Table 6.2, "Revision Interoperability during an Explicit Contract" shows the Specification Revision that Shall be used between the Port Partners and the Cable Plugs when the Specification Revision has been discovered and an Explicit Contract is in place. Notes:  A VCONN Source that does not communicate with the Cable Plug(s) May skip the above procedure.  When a Cable Plug does not respond to a Revision 3.x Discover Identity REQ with a Discover Identity ACK or BUSY the VCONN Source May repeat steps 1-4 using a Revision 2.0 Discover Identity REQ in step 1 before establishing that there is no Cable Plug to communicate with. A VCONN Source that supports Revision 3.x of the Power Delivery Specification May communicate with a Cable Plug also supporting Revision 3.x using Revision 3.x Compliant Communications regardless of the Specification Revision of its Port Partner while no Explicit Contract exists. After an Explicit Contract has been established the Port Partners and Cable Plug(s) Shall use Table 6.2, "Revision Interoperability during an Explicit Contract" to determine the Revision to be used. All data in all Messages Shall be consistent with the Specification Revision field in the Message Header for that particular Message. A Cable Plug Shall Not save the state of the agreed Specification Revision. A Cable Plug Shall respond with the highest Specification Revision it supports that is equal to or lower than the Specification Revision contained in the Message received from the VCONN Source. Cable Plugs Shall operate using the same Specification Revision for both SOP’ and SOP’’. Cable assemblies with two Cable Plugs Shall operate using the same Specification Revision for both Cable Plugs. See Table 6.2, "Revision Interoperability during an Explicit Contract" for details of how various Revisions Shall inter-operate. 6.2.1.1.6 Port Data Role The 1-bit Port Data Role field Shall indicate the Port's present Data Role:  0b UFP  1b DFP Table 6.2 Revision Interoperability during an Explicit Contract Port 1 Revision Cable Plug Revision Port 2 Revision Port to Port Operating Revision Port to Cable Plug Operating Revision 2 2 2 2 2 2 2 3 2 2 2 3 2 2 2 2 3 3 2 2 3 2 2 2 2 3 2 3 3 2 3 3 2 2 2 3 3 3 3 3 Page 120 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Port Data Role field Shall only be defined for SOP Packets. For all other SOP* Packets the Port Data Role field is Reserved and Shall be set to zero. If a USB Type-C Port receives a Message with the Port Data Role field set to the same Data Role as its current Data Role, except for the GoodCRC Message, USB Type-C Error Recovery actions as defined in [USB Type-C 2.4] Shall be performed. For a USB Type-C Port the Port Data Role field Shall be set to the default value at Attachment after a Hard Reset: 0b for a Port with Rd asserted and 1b for a Port with Rp asserted. In the case that a Port is not USB Communications capable, at Attachment a Source Port Shall default to DFP and a Sink Port Shall default to UFP. 6.2.1.1.7 Cable Plug The 1-bit Cable Plug field Shall indicate whether this Message originated from a Cable Plug or VPD:  0b Message originated from a DFP or UFP.  1b Message originated from a Cable Plug or VPD The Cable Plug field Shall only apply to SOP’ Packet and SOP’’ Packet types. 6.2.1.1.8 Message Type The 5-bit Message Type field Shall indicate the type of Message being sent. To fully decode the Message Type, the Number of Data Objects field is first examined to determine whether the Message is a Control Message or a Data Message. Then the specific Message Type can be found in Table 6.5, "Control Message Types" or Table 6.6, "Data Message Types". The Message Type field Shall apply to all SOP* Packet types. 6.2.1.2 Extended Message Header Extended Messages (indicated by the Extended field being set in the Message Header) Shall contain an Extended Message Header following the Message Header as shown in Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and defined in “Table 6.3, "Extended Message Header". Extended Messages contain Data Blocks of Data Size, defined in the Extended Message, that are either sent in a single Message or as a series of Chunks. When the Data Block is sent as a series of Chunks, each Chunk in the series, except for the last Chunk, Shall contain MaxExtendedMsgChunkLen bytes. The last Chunk in the series Shall contain the remainder of the Data Block and so could be less than MaxExtendedMsgChunkLen bytes and Shall be padded to the next 4-byte Data Object boundary. 6.2.1.2.1 Chunked The Port Partners Shall use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine whether to send Messages of Data Size > MaxExtendedMsgLegacyLen bytes in a single Unchunked Extended Message (see Section 6.4.1.2.1.6, "Unchunked Extended Messages Supported" and Section 6.4.2.6, "Unchunked Extended Messages Supported"). Table 6.3 Extended Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Chunked Section 6.2.1.2.1 14…11 SOP* Chunk Number Section 6.2.1.2.2 10 SOP* Request Chunk Section 6.2.1.2.3 9 SOP* Reserved 8…0 SOP* Data Size Section 6.2.1.2.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 121 When either Port Partner only supports Chunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to one.  Every Extended Message of Data Size > MaxExtendedMsgLegacyLen Shall be transmitted between the Port Partners in Chunks  The Number of Data Objects in the Message Header Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When both Port Partners support Unchunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to zero.  Every Extended Message Shall be transmitted between the Port Partners Unchunked.  The Number of Data Objects in the Message Header is Reserved. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When sending Extended Messages to the Cable Plug the VCONN Source Shall only send Chunked Extended Messages. Cable Plugs Shall always send Extended Messages of Data Size > MaxExtendedMsgLegacyLen Chunked and Shall set the Chunked bit in every Extended Message to one. When Extended Messages are supported Chunking Shall be supported. 6.2.1.2.2 Chunk Number The Chunk Number field Shall only be Valid in a Message if the Chunked flag is set to one. If the Chunked flag is set to zero the Chunk Number field Shall also be set to zero. The Chunk Number field is used differently depending on whether the Message is a request for Data, or a requested Data Block being returned:  In a request for data the Chunk Number field indicates the number of the Chunk being requested. The requester Shall only set this field to the number of the next Chunk in the series (the next Chunk after the last received Chunk).  In the requested Data Block the Chunk Number field indicates the number of the Chunk being returned. The Chunk Number for each Chunk in the series Shall start at zero and Shall increment for each Chunk by one up to a maximum of 9 corresponding to 10 Chunks in total. 6.2.1.2.3 Request Chunk The Request Chunk bit Shall only be used for the Chunked transfer of an Extended Message when the Chunked bit is set to 1 (see Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)"). For Unchunked Extended Message transfers, Messages Shall be sent and received without the request/response mechanism (see Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)"). The Request Chunk bit Shall be set to one to indicate that this is a request for a Chunk of a Data Block and Shall be set to zero to indicate that this is a Chunk response containing a Chunk. Except for Chunk zero, a requested Chunk of a Data Block Shall only be returned as a Chunk response to a corresponding request for that Chunk. Both the Chunk request and the Chunk response Shall contain the same value in the Message Type field. When the Request Chunk bit is set to one the Data Size field Shall be zero. Page 122 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.2.1.2.4 Data Size The Data Size field Shall indicate how many bytes of data in total are in Data Block being returned. The total number of data bytes in the Message Shall Not exceed MaxExtendedMsgLen. If the Data Size field is less than MaxExtendedMsgLegacyLen and the Chunked bit is set then the Packet Payload Shall be padded to the next 4-byte Data Object boundary with zeros (0x00). If the Data Size field is greater than expected for a given Extended Message but less than or equal to MaxExtendedMsgLen then the expected fields in the Message Shall be processed appropriately and the additional fields Shall be Ignored. 6.2.1.2.5 Extended Message Examples The following examples illustrate the transmission of Extended Messages both Chunked (Chunked bit is one) and Unchunked (Chunked bit is zero). The examples use a Security_Request Message of Data Size 7 bytes which is responded to by a Security_Response Message of Data Size 30 bytes. The sizes of these Messages are arbitrary and are used to illustrate Message transmission; they are not intended to correspond to genuine security related Messages. During Negotiation of the Explicit Contract after connection, the Port Partners use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine the value of the Chunked bit (see Table 6.4, "Use of Unchunked Message Supported bit"). When both Port Partners support Unchunked Extended Messages then the Chunked bit is zero otherwise the Chunked bit is one. The Chunked bit is used to determine whether:  The Chunk request/response mechanism is used.  Extended Messages are Chunked.  Padding is applied.  The Number of Data Objects field is used. The following examples illustrate the expected usage in each case. 6.2.1.2.5.1 Security_Request/Security_Response Unchunked Example Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Unchunked Extended Messages (Chunked bit is zero) between a USB Host and a Charger. The entire Data Block is returned in one Message. The Chunk request/response mechanism is not used. Table 6.4 Use of Unchunked Message Supported bit Source: Source_Capabilities Message Unchunked Message Supported bit = 0 Unchunked Message Supported bit = 1 Sink: Request Message Unchunked Message Supported bit = 0 Chunked bit = 1 Chunked bit = 1 Unchunked Message Supported bit = 1 Chunked bit = 1 Chunked bit = 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 123 Figure 6.4 Example Security_Request sequence Unchunked (Chunked bit = 0) Figure 6.5, "Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero)" details the Security_Request Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to 0, which in this case is 7 bytes. Figure 6.5 Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero) Figure 6.6, "Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero)" details the Security_Response Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to zero, which in this case is 30 bytes. Host Charger Security_Request (Data Size = 7, Chunked = 0) GoodCRC GoodCRC Security_Response (Data Size = 30, Chunked = 0) Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 0 (Reserved) Data (7 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 Page 124 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.6 Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero) 6.2.1.2.5.2 Security_Request/Security_Response Chunked Example Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Chunked Extended Messages (Chunked bit is one) between a USB Host and a Charger. Note: Chunk Number zero in every Extended Message is sent without the need for a Chunk Request, but Chunk Number one and following need to be requested with a Chunk request. Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 0 (Reserved) Data (30 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B28 B29 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 125 Figure 6.7 Example Security_Request sequence Chunked (Chunked bit = 1) Figure 6.8, "Example Security_Request Message of Data Size 7 (Chunked bit set to 1)" shows the Security_Request Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Three bytes of padding have been added to the Message so that the total number of bytes is a multiple of 32-bits, corresponding to 3 Data Objects. The Number of Data Objects field is set to 3 to indicate the length of this Chunk. The Chunk Number is set to zero and the Data Size field is set to 7 to indicate the length of the whole Extended Message. Host Charger Security_Request (Number of Data Objects = 3, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 7) GoodCRC GoodCRC Security_Response (Number of Data Objects = 7, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 30) Security_Response “Chunk request” (Number of Data Objects = 1, Chunked = 1, Chunk Number = 1, Request Chunk = 1, Data Size = 0) GoodCRC GoodCRC Security_Response (Number of Data Objects = 2, Chunked = 1, Chunk Number = 1, Request Chunk = 0, Data Size = 30) Security_Request Chunk Security_Response Page 126 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.8 Example Security_Request Message of Data Size 7 (Chunked bit set to 1) Figure 6.9, "Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number zero of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. No padding is need for this Chunk since the full 26-byte Payload plus 2-byte Extended Message Header is a multiple of 32-bits, corresponding to 7 Data Objects. The Number of Data Objects field is set to 7 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.9 Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" shows an example of the Message format, byte ordering and padding for the Security_Response Message Chunk request for Chunk Number one shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)". In the Chunk request the Number of Data Objects field in the Message is set to 1 to indicate that the Payload is 32 bits equivalent to 1 data object (see Figure 6.10, "Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1)"). Since the Chunked bit is set to 1 the Chunk request/Chunk response mechanism is used. The Message is a Chunk request so the Request Chunk bit is set to one, and in this case Chunk one is being requested so Chunk Number is set to one. Data Size is set to zero indicating the length of the Data Block being transferred. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits. Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 3 Data (7 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 P0 (0x00) P1 (0x00) P2 (0x00) Padding (3 bytes) Data Object 0 Data Object 1 Data Object 2 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 7 Data (26 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B22 B23 Data Object 0 B24 B25 Data Object 6 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 127 Figure 6.10 Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1) Figure 6.11, "Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number one of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits, corresponding to 2 Data Objects. The Number of Data Objects field is set to 2 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.11 Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 1 Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 1 Data Size = 0 Message Header LSB Message Header MSB Message Header LSB Message Header MSB P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 2 Data (4 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Data Object 1 Page 128 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3 Control Message A Message is defined as a Control Message when the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. The Protocol Layer originates the Control Messages (i.e., Accept Message, Reject Message etc.). The Control Message types are specified in the Message Header's Message Type field (bits 4…0) and are summarized in Table 6.5, "Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.5 Control Message Types Bits 4…0 Message Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 0_0001 GoodCRC Source, Sink or Cable Plug See Section 6.3.1. SOP* 0_0010 GotoMin (Deprecated) Deprecated See Section 6.3.2. N/A 0_0011 Accept Source, Sink or Cable Plug See Section 6.3.3. SOP* 0_0100 Reject Source, Sink or Cable Plug See Section 6.3.4. SOP* 0_0101 Ping (Deprecated) Deprecated See Section 6.3.5. SOP only 0_0110 PS_RDY Source or Sink See Section 6.3.6. SOP only 0_0111 Get_Source_Cap Sink or DRP See Section 6.3.7. SOP only 0_1000 Get_Sink_Cap Source or DRP See Section 6.3.8. SOP only 0_1001 DR_Swap Source or Sink See Section 6.3.9. SOP only 0_1010 PR_Swap Source or Sink See Section 6.3.10. SOP only 0_1011 VCONN_Swap Source or Sink See Section 6.3.11. SOP only 0_1100 Wait Source or Sink See Section 6.3.12. SOP only 0_1101 Soft_Reset Source or Sink See Section 6.3.13. SOP* 0_1110 Data_Reset Source or Sink See Section 6.3.14. SOP only 0_1111 Data_Reset_Complete Source or Sink See Section 6.3.15. SOP only 1_0000 Not_Supported Source, Sink or Cable Plug See Section 6.3.16. SOP* 1_0001 Get_Source_Cap_Extended Sink or DRP See Section 6.3.17. SOP only 1_0010 Get_Status Source or Sink See Section 6.3.18. SOP* 1_0011 FR_Swap Sink1 See Section 6.3.19. SOP only 1_0100 Get_PPS_Status Sink See Section 6.3.20. SOP only 1_0101 Get_Country_Codes Source or Sink See Section 6.3.21. SOP only 1_0110 Get_Sink_Cap_Extended Source or DRP See Section 6.3.22. SOP only 1_0111 Get_Source_Info Sink or DRP See Section 6.3.23. SOP Only 1_1000 Get_Revision Source or Sink See Section 6.3.24. SOP* 1_1001… 1_1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 1) In this case the Port is providing vSafe5V however it will have Rd asserted rather than Rp and sets the Port Power Role field to Sink, until the Fast Role Swap AMS has completed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 129 6.3.1 GoodCRC Message The GoodCRC Message Shall be sent by the receiver to acknowledge that the previous Message was correctly received (i.e., had a GoodCRC Message). The GoodCRC Message Shall return the Message's MessageID so the sender can determine that the correct Message is being acknowledged. The first bit of the GoodCRC Message Shall be returned within tTransmit after receipt of the last bit of the previous Message. BIST does not send the GoodCRC Message while in a Continuous BIST Mode (see Section 6.4.3, "BIST Message"). The retry mechanism is triggered when the Message sender fails to receive a GoodCRC Message before the CRCReceiveTimer expires. It is used by the Message sender to detect that the Message was not correctly received by the Message recipient due to noise or other disturbance on the Configuration Channel (CC). The retry mechanism Shall Not be used for any other purpose such as a means of gaining time for processing the required response to the received Message. 6.3.2 GotoMin Message (Deprecated) The GotoMin (Deprecated) Message has been Deprecated. The 0_0010 Message Type is no longer Valid and Shall be responded to by a Not_Supported Message. 6.3.3 Accept Message The Accept Message is a Valid response in the following cases:  It Shall be sent by the Source, in SPR Mode, to signal the Sink that the Source is willing to meet the Request Message.  It Shall be sent by the Source, in EPR Mode, to signal the Sink that the Source is willing to meet the EPR_Request Message.  It Shall be sent by the recipient of the PR_Swap Message to signal that it is willing to do a Power Role Swap and has begun the Power Role Swap AMS.  It Shall be sent by the recipient of the DR_Swap Message to signal that it is willing to do a Data Role Swap and has begun the Data Role Swap AMS.  It Shall be sent by the recipient of the VCONN_Swap Message to signal that it is willing to do a VCONN Swap and has begun the VCONN Swap AMS.  It Shall be sent by the recipient of the FR_Swap Message to indicate that it has begun the Fast Role Swap AMS.  It Shall be sent by the recipient of the Soft_Reset Message to indicate that it has completed its Soft Reset.  It Shall be sent by the recipient of the Enter_USB Message to indicate that it has begun the Enter USB AMS.  It Shall be sent by the recipient of the Data_Reset Message to indicate that it has begun the Data Reset AMS. The Accept Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.6.2, "SenderResponseTimer"). 6.3.4 Reject Message The Reject Message is a Valid response in the following cases:  It Shall be sent to signal the Sink, in SPR Mode, that the Source is unable to meet the Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised. Page 130 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  It Shall be sent to signal the Sink, in EPR Mode, that the Source is unable to meet the EPR_Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is unable to do a Power Role Swap.  It Shall be sent by the recipient of a PR_Swap Message while in EPR Mode.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source, to indicate it is unable to do a VCONN Swap.  It Shall be sent by UFP on receiving an Enter_USB Message to indicate it is unable to enter the requested USB Mode. The sender of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message, on receiving a Reject Message response, Shall Not send this same Message to the recipient until one of the following has occurred:  A New Explicit Contract Negotiation as a result of the Source sending a Source_Capabilities Message or EPR_Source_Capabilities Message. This can be triggered by:  The Source's Device Policy Manager.  A Get_Source_Cap Message sent from the Sink to the Source in SPR Mode.  An EPR_Get_Source_Cap Message sent from the Sink to the Source in EPR Mode.  A Power Role Swap.  A Soft Reset.  A Hard Reset.  A Disconnect/Re-connect.  A Data Role Swap.  A Data Reset. The Sink May send a different Request Message to the one which was rejected but Shall Not repeat the same Request Message, using the same RDO, unless there has been a New Explicit Contract Negotiation, Data Role Swap or Data Reset as described above. The Reject Message Shall be sent within tReceiverResponse of the receipt of the last bit of Message (see Section 6.6.2, "SenderResponseTimer"). Note: The Reject Message is not a Valid response when a Message is not supported. In this case the Not_Supported Message is returned (see Section 6.3.16, "Not_Supported Message"). 6.3.5 Ping Message The Ping (Deprecated) Message has been deprecated. The 0_0101 Message Type is no longer Valid. A Port that receives a Ping (Deprecated) Message May respond with a Not_Supported Message or Ignore the Ping (Deprecated) Message. A Cable Plug that receives a Ping (Deprecated) Message Shall Ignore the Ping (Deprecated) Message. 6.3.6 PS_RDY Message The PS_RDY Message Shall be sent by the Source (or by both the New Sink and New Source during the Power Role Swap AMS or Fast Role Swap AMS) to indicate its power supply has reached the desired operating condition (see Section 8.3.2.2, "Power Negotiation"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 131 6.3.7 Get_Source_Cap Message The Get_Source_Cap (Get Source Capabilities) Message May be sent by a Port to request the Source Capabilities and Dual-Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message"). 6.3.8 Get_Sink_Cap Message The Get_Sink_Cap (Get Sink Capabilities) Message May be sent by a Port to request the Sink Capabilities and Dual- Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message"). 6.3.9 DR_Swap Message The DR_Swap Message is used to exchange DFP and UFP operation between Port Partners while maintaining the direction of power flow over VBUS. The Data Role Swap process can be used by Port Partners whether or not they support USB Communications capability. A DFP that supports USB Communication capability starts as the USB Host on Attachment. A UFP that supports USB Communication capability starts as the USB Device on Attachment. [USB Type-C 2.4] Dual-Role Data (DRD) Ports Shall have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. DFPs and UFPs May have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. A Data Role Swap Shall be regarded in the same way as a cable Detach/ Re-attach in relation to any USB Communication which is ongoing between the Port Partners. If there are any Active Modes between the Port Partners when a DR_Swap Message is a received, then a Hard Reset Shall be performed (see Section 6.4.4.3.4, "Enter Mode Command"). If the Cable Plug has any Active Modes then the DFP Shall Not issue a DR_Swap Message and Shall cause all Active Modes in the Cable Plug to be exited before accepting a Data Role Swap request. The source of VBUS and VCONN Source Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the Data Role Swap process. The DR_Swap Message May be sent by either Port Partner. The recipient of the DR_Swap Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait").  If an Accept Message is sent, the Source and Sink Shall exchange Data Roles.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Data Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Data Role Swap might be possible in the future but that no immediate action Shall be taken. Before a Data Role Swap the initial DFP Shall have its Port Data Role bit set to DFP, and the initial UFP Shall have its Port Data Role bit set to UFP. After a successful Data Role Swap the DFP/Host Shall become the UFP/Device and vice-versa; the new DFP Shall have its Port Data Role bit set to DFP, and the new UFP Shall have its Port Data Role bit set to UFP. Where USB Communication is supported by both Port Partners a USB data connection Should be established according to the new Data Roles. If the Data Role Swap, after having been accepted by the Port Partner, is subsequently not successful, in order to attempt a re-establishment of the connection, USB Type-C Error Recovery actions, such as disconnect, as defined in [USB Type-C 2.4] will be necessary. See Section 8.3.2.9, "Data Role Swap". 6.3.10 PR_Swap Message The PR_Swap Message May be sent by either Port Partner to request an exchange of Power Roles. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). Page 132 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If an Accept Message is sent, the Source and Sink Shall do a Power Role Swap.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Power Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Power Role Swap might be possible in the future but that no immediate action Shall be taken. The PR_Swap Message Shall Not be sent while in EPR Mode. While in EPR Mode if a Power Role Swap is required, an EPR Mode exit Shall be done first. After a successful Power Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the New Source Shall also reset its CapsCounter. The New Source Shall have Rp asserted on the CC wire and the New Sink Shall have Rd asserted on the CC wire as defined in [USB Type-C 2.4]. When performing a Power Role Swap from Source to Sink, the Port Shall change its CC wire resistor from Rp to Rd. When performing a Power Role Swap from Sink to Source, the Port Shall change its CC wire resistor from Rd to Rp. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged by the Power Role Swap process. Note: During the Power Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Power Role Swap, refer to:  Section 7.3.2, "Transitions Caused by Power Role Swap"  Section 8.3.2.5, "Data Reset".  Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram".  Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram".  Section 9.1.2, "Mapping to USB Device States". 6.3.11 VCONN_Swap Message The VCONN_Swap Message Shall be supported by any Port that can operate as a VCONN Source. The VCONN_Swap Message May be sent by either Port Partner to request an exchange of VCONN Source. The recipient of the Message Shall respond by sending an Accept Message, Reject Message, Wait Message (see Section 6.9, "Accept, Reject and Wait") or Not_Supported Message.  If an Accept Message is sent, the Port Partners Shall perform a VCONN Swap. The new VCONN Source Shall send a PS_RDY Message within tVcONNSourceOn to indicate that it is now sourcing VCONN. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of receipt of the last bit of the EOP of the PS_RDY Message.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a VCONN Swap and no action Shall be taken. A Reject Message Shall only be sent by the Port that is not presently the VCONN Source in response to a VCONN_Swap Message. The Port that is presently the VCONN Source Shall Not send a Reject Message in response to VCONN_Swap Message.  If a Wait Message is sent, the requester is informed that a VCONN Swap might be possible in the future but that no immediate action Shall be taken. A Port after losing the VCONN Source role due to incoming VCONN Swap request Shall Not initiate a VCONN Swap until at least tVCONNSwapDelayDFP/ tVCONNSwapDelayUFP after completing the previous VCONN Swap AMS.  If a Not_Supported Message is sent, the requester is informed that VCONN Swap is not supported. The Port that is not presently the VCONN Source May turn on VCONN when a Not_Supported Message is received in response to a VCONN_Swap Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 133 The DFP (Host), UFP (Device) Data Roles and Source of VBUS Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the VCONN Swap process. VCONN Shall be continually sourced during the VCONN Swap process to maintain power to the Cable Plug(s) i.e., make before break. Before communicating with a Cable Plug a Port Shall ensure that it is the VCONN Source and that the Cable Plugs are powered, by performing a VCONN Swap if necessary. Since it cannot be guaranteed that the present VCONN Source is supplying VCONN, the only means to ensure that the Cable Plugs are powered is for a Port wishing to communicate with a Cable Plug to become the VCONN Source. If a Not_Supported Message is returned in response to the VCONN_Swap Message, then the Port is allowed to become the VCONN Source until a Hard Reset or Detach. A VCONN Source that is also a Source can attempt to send a Discover Identity Command using SOP’ to a Cable Plug prior to the establishment of the First Explicit Contract. Note: Even when it is presently the VCONN Source, the Sink is not permitted to initiate an AMS with a Cable Plug unless Rp is set to SinkTxOK (see Section 6.9, "Accept, Reject and Wait"). 6.3.12 Wait Message The Wait Message is a Valid response to one of the following Messages:  It Shall be sent to signal the Sink, in response to a Request Message in SPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent to signal the Sink, in response to a EPR_Request Message in EPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is currently unable to do a Power Role Swap.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is currently unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source to indicate it is currently unable to do a VCONN Swap.  It Shall be sent by the recipient of an Enter_USB Message to indicate it is currently unable to enter the requested USB Mode. The Wait Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.9, "Accept, Reject and Wait"). 6.3.12.1 Wait in response to a Request Message The Wait Message allows the Source time to recover the power it requires to meet the request, e.g., through Re- negotiation with other Sinks or an upstream Source. A Source Should only send a Wait Message in response to a Request Message when an Explicit Contract exists between the Port Partners. The Sink is allowed to repeat the Request Message using the SinkRequestTimer and Shall ensure that there is tSinkRequest after receiving the Wait Message before sending another Request Message. 6.3.12.2 Wait in response to a PR_Swap Message The Wait Message is used when responding to a PR_Swap Message to indicate that a Power Role Swap might be possible in the future. This can occur in any case where the device receiving the PR_Swap Message needs to evaluate the request further e.g., by requesting Sink Capabilities from the originator of the PR_Swap Message. Once it has completed this evaluation one of the Port Partners Should initiate the Power Role Swap process again by sending a PR_Swap Message. The Wait Message is also used where a Hub is operating in hybrid mode when a request cannot be satisfied (see [UCSI]). Page 134 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A Port that receives a Wait Message in response to a PR_Swap Message Shall wait tPRSwapWait after receiving the Wait Message before sending another PR_Swap Message. 6.3.12.3 Wait in response to a DR_Swap Message The Wait Message is used when responding to a DR_Swap Message to indicate that a Data Role Swap might be possible in the future. This can occur in any case where the device receiving the DR_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the Data Role Swap process again by sending a DR_Swap Message. A Port that receives a Wait Message in response to a DR_Swap Message Shall wait tDRSwapWait after receiving the Wait Message before sending another DR_Swap Message. 6.3.12.4 Wait in response to a VCONN_Swap Message The Wait Message is used when responding to a VCONN_Swap Message to indicate that a VCONN_Swap might be possible in the future. This can occur in any case where the device receiving the VCONN_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the VCONN Swap process again by sending a VCONN_Swap Message. A Port that receives a Wait Message in response to a VCONN_Swap Message Shall wait tVCONNSwapWait after receiving the Wait Message before sending another VCONN_Swap Message. A Port that is currently the VCONN Source Shall respond with an Accept Message (rather than a Wait Message) if the Port Partner's Revision and Version, as reported in the Revision Message, is earlier than R3.2 V1.1. A Port Partner supporting an earlier Revision and Version will not expect a Wait Message and will generate a Soft Reset in response. 6.3.12.5 Wait in response to an Enter_USB Message The Wait Message is used, by the UFP, when responding to an Enter_USB Message to indicate that entering the requested USB Mode might be possible in the future. This can occur, for example, in any case where the UFP needs to Negotiate more power to enter the mode. Once the UFP has completed this the DFP Should initiate the Enter USB process again by sending an Enter_USB Message. A DFP that receives a Wait Message in response to an Enter_USB Message Shall wait tEnterUSBWait after receiving the Wait Message before sending another Enter_USB Message. 6.3.13 Soft Reset Message A Soft_Reset Message May be initiated by either the Source or Sink to its Port Partner requesting a Soft Reset. The Soft_Reset Message Shall cause a Soft Reset of the connected Port Pair (see Section 6.8.1, "Soft Reset and Protocol Error"). If the Soft_Reset Message fails a Hard Reset Shall be initiated within tHardReset of the last CRCReceiveTimer expiring after nRetryCount retries have been completed. A Soft_Reset Message is used to recover from Protocol Layer errors; putting the Message counters to a known state to regain Message synchronization. The Soft_Reset Message has no effect on the Source or Sink; that is the previously Negotiated direction. Voltage and current remain unchanged. Modal Operation is unaffected by Soft Reset. However after a Soft Reset has completed, an Explicit Contract Negotiation occurs, in order to re-establish PD Communication and to bring state operation for both Port Partners back to either the PE_SNK_Ready or PE_SRC_Ready states as appropriate (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams"). A Soft_Reset Message May be sent by either the Source or Sink when there is a Message synchronization error. If the error is not corrected by the Soft Reset, Hard Reset Signaling Shall be issued (see Section 6.8.3, "Hard Reset"). A Soft_Reset Message Shall be targeted at a specific entity depending on the type of SOP* Packet used. Soft_Reset Messages sent using SOP Packets Shall Soft Reset the Port Partner only. Soft_Reset Messages sent using SOP’ Packet/ SOP’’ Packets Shall Soft Reset the corresponding Cable Plug only. After a VCONN Swap the VCONN Source needs to reset the Cable Plug's Protocol Layer to ensure MessageID synchronization. If after a VCONN Swap the VCONN Source wants to communicate with a Cable Plug using SOP’ Packets, it Shall issue a Soft_Reset Message using a SOP’ Packet in order to reset the Cable Plug's Protocol Layer. If Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 135 the VCONN Source wants to communicate with a Cable Plug using SOP’’ Packets, it Shall issue a Soft_Reset Message using a SOP’’ Packet in order to reset the Cable Plug's Protocol Layer. 6.3.14 Data_Reset Message The Data_Reset Message May be sent by either the DFP or UFP and Shall reset the USB data connection and exit all Alternate Modes with its Port Partner while preserving the power on VBUS. USB4® Mode capable ports Shall support the Data_Reset Message and other ports May support the Data_Reset Message. The Data_Reset Message Shall Not change the existing:  Power Contract  Data Roles (i.e., which Port is the DFP or UFP) The receiver of the Data_Reset Message Shall respond by sending an Accept Message and then follow the process outlined in the following steps. Neither the sender nor receiver Shall initiate a VCONN Swap until the Data Reset process is complete, and the Data_Reset_Complete Message has been sent. Following receipt of the Accept Message, or GoodCRC following the Accept, depending which Port sends the Data_Reset Message: 1) The DFP Shall:  Disconnect the Port's [USB 2.0] D+/D- signals.  If operating in [USB 3.2] remove the Port's Rx Terminations (see [USB 3.2]).  If operating in [USB4] drive the Port's SBTX to a logic low (see [USB4]). 2) Both the DFP and UFP Shall exit all Alternate Modes if any. 3) Reset the cable:  If the VCONN Source Port is also the UFP, then it Shall run the UFP VCONN Power Cycle process de- scribed in Section 7.1.15.1, "UFP VCONN Power Cycle".  If the VCONN Source Port is also the DFP, then it Shall run the DFP VCONN Power Cycle process de- scribed in Section 7.1.15.2, "DFP VCONN Power Cycle".  The DFP Shall exit the VCONN Power Cycle process as the VCONN Source and be sourcing VCONN. 4) After tDataReset the DFP Shall:  Reconnect the [USB 2.0] D+/D- signals.  If the Port was operating in [USB 3.2] or [USB4] reapply the Port's Rx Terminations (see [USB 3.2]). 5) The Data Reset process is complete; the DFP Shall send a Data_Reset_Complete Message and enter the USB4® Discovery and Entry Flow (See [USB Type-C 2.4]). If the Initiator of the Data_Reset Message does not receive a Valid response within tSenderResponse it Shall enter the ErrorRecovery State. 6.3.15 Data_Reset_Complete Message The Data_Reset_Complete Message Shall be sent by the DFP to the UFP to indicate the completion of the Data Reset process (see Section 6.3.14, "Data_Reset Message"). 6.3.16 Not_Supported Message The Not_Supported Message Shall be sent by a Port or Cable Plug in response to any Message it does not support. Returning a Not_Supported Message is assumed in this specification and has not been called out explicitly except in Section 6.13, "Message Applicability" which defines cases where the Not_Supported Message is returned. Page 136 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3.17 Get_Source_Cap_Extended Message The Get_Source_Cap_Extended Message is sent by a Port to request additional information about a Port's Source Capabilities. The Port Shall respond by returning a Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message"). 6.3.18 Get_Status Message The Get_Status Message is sent by a Port using SOP to request the Port Partner's present status. The Port Partner Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). A Port that receives an Alert Message (see Section 6.4.6, "Alert Message") indicates that the Source or Sink's Status has changed and Should be re-read using a Get_Status Message. The Get_Status Message May also be sent to an Active Cable to get its present status using SOP’/SOP’’. The Active Cable Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). 6.3.19 FR_Swap Message The FR_Swap Message Shall be sent by the New Source within tFRSwapInit after it has detected a Fast Role Swap signal (see Section 5.8.6.3, "Fast Role Swap Detection" and Section 6.6.17.3, "tFRSwapInit"). The Fast Role Swap AMS is necessary to apply Rp to the New Source and Rd to the New Sink and to re-synchronize the state machines. The tFRSwapInit time Shall be measured from the time the Fast Role Swap Request has been sent for tFRSwapRx (max) until the last bit of the EOP of the FR_Swap Message has been transmitted by the PHY Layer. The recipient of the FR_Swap Message Shall respond by sending an Accept Message. After a successful Fast Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the Source Shall also reset its CapsCounter. This ensures that only the Cable Plug responds with a GoodCRC Message to the Discover Identity Command. Prior to the Fast Role Swap AMS, the New Source Shall have Rd asserted on the CC wire and the New Sink Shall have Rp asserted on the CC wire. Note: This is an incorrect assignment of Rp/Rd (since Rp follows the Source and Rd follows the Sink as defined in [USB Type-C 2.4]) that is corrected by the Fast Role Swap AMS. During the Fast Role Swap AMS, the New Source Shall change its CC wire resistor from Rd to Rp and the New Sink Shall change its CC wire resistor from Rp to Rd. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged during the Fast Role Swap process. The Initial Source Should avoid being the VCONN Source (by using the VCONN Swap process) whenever not actively communicating with the cable, since it is difficult for the Initial Source to maintain VCONN power during the Fast Role Swap process. Note: A Fast Role Swap is a "best effort" solution to a situation where a PDUSB Device has lost its external power. This process can occur at any time, even during an AMS in which case error handling such as Hard Reset or [USB Type-C 2.4] Error Recovery will be triggered. Note: During the Fast Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Fast Role Swap process, refer to:  Section 7.1.13, "Fast Role Swap"  Section 7.2.10, "Fast Role Swap"  Section 8.3.3.19.5, "Policy Engine in Source to Sink Fast Role Swap State Diagram"  Section 8.3.3.19.6, "Policy Engine in Sink to Source Fast Role Swap State Diagram" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 137  Section 9.1.2, "Mapping to USB Device States" for VBUS mapping to USB states. 6.3.20 Get_PPS_Status The Get_PPS_Status Message is sent by the Sink to request additional information about a Source's status. The Port Shall respond by returning a PPS_Status Message (see Section 6.5.10, "PPS_Status Message"). 6.3.21 Get_Country_Codes The Get_Country_Codes Message is sent by a Port to request the alpha-2 country codes its Port Partner supports as defined in [ISO 3166]. The Port Partner Shall respond by returning a Country_Codes Message (see Section 6.5.11, "Country_Codes Message"). 6.3.22 Get_Sink_Cap_Extended Message The Get_Sink_Cap_Extended (Get Sink Capabilities Extended) Message is sent by a Port to request additional information about a Port's Sink Capabilities. The Port Shall respond by returning a Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). 6.3.23 Get_Source_Info Message The Get_Source_Info Message is sent by a Port to request the type, maximum Capabilities and present Capabilities of the Port when it is operating as a Source. The Port Shall respond by returning the Source_Info Message (See Section 6.4.11, "Source_Info Message"). 6.3.24 Get_Revision Message The Get_Revision Message is sent by a Port using SOP to request the Revision and Version of the Power Delivery Specification its Port Partner supports. The Port Partner Shall respond by returning a Revision Message (See Section 6.4.12, "Revision Message"). The Get_Revision Message May also be sent to a Cable Plug to request the Revision and Version of the Power Delivery Specification it supports using SOP’/SOP’’. The Active Cable Shall respond by returning a Revision Message (see Section 6.4.12, "Revision Message"). Page 138 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4 Data Message A Data Message Shall consist of a Message Header and be followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is a non-zero value. There are many types of Data Objects used to compose Data Messages. Some examples are:  Power Data Object (PDO) used to expose a Source Port's power Capabilities or a Sink's power requirements.  Request Data Object (RDO) used by a Sink Port to Negotiate an Explicit Contract.  Vendor Data Object (VDO) used to convey vendor specific information.  BIST Data Object (BDO) used for PHY Layer compliance testing.  Battery Status Data Object (BSDO) used to convey Battery status information.  Alert Data Object (ADO) used to indicate events occurring on the Source or Sink. The type of Data Object being used in a Data Message is defined by the Message Header's Message Type field and is summarized in Table 6.6, "Data Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.6 Data Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0_0001 Source_Capabilities Source or Dual-Role Power See Section 6.4.1.5 SOP only 0_0010 Request Sink only See Section 6.4.2 SOP only 0_0011 BIST Tester, Source or Sink See Section 6.4.3 SOP* 0_0100 Sink_Capabilities Sink or Dual-Role Power See Section 6.4.2 SOP only 0_0101 Battery_Status Source or Sink See Section 6.4.5 SOP only 0_0110 Alert Source or Sink See Section 6.4.6 SOP only 0_0111 Get_Country_Info Source or Sink See Section 6.4.7 SOP only 0_1000 Enter_USB DFP See Section 6.4.8 SOP* 0_1001 EPR_Request Sink See Section 6.4.9 SOP only 0_1010 EPR_Mode Source or Sink See Section 6.4.10 SOP only 0_1011 Source_Info Source See Section 6.4.11 SOP only 0_1100 Revision Source, Sink or Cable Plug See Section 6.4.12 SOP* 0_1101…0 _1110 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0 1111 Vendor_Defined Source, Sink or Cable Plug See Section 6.4.4 SOP* 1_0000…1 _1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 139 6.4.1 Capabilities Message There are two distinct Capabilities Messages: one used while in SPR Mode and another while in EPR Mode. This section defines the Capabilities Messages specific to the SPR Mode and Section 6.5.15, "EPR Capabilities Message" defines the Capabilities Messages specific to the EPR Mode. 6.4.1.1 Power Data Objects Sections Section 6.4.1.5, "SPR Source Capabilities Message" and Section 7.1.3, "Types of Sources" describes the Power Data Objects (PDOs) used in the construction of a Capabilities Message for both SPR Mode and EPR Mode. There are three types of Power Data Objects. They contain additional information beyond that encoded in the Message Header to identify each of the three types of Power Data Objects:  Fixed Supply is used to expose well-regulated fixed voltage power supplies.  Variable Supply is used to expose very poorly regulated power supplies.  Battery Supply is used to expose batteries that can be directly connected to VBUS. There are three types of Augmented Power Data Objects:  SPR PPS is used to expose a power supply whose output voltage can be programmatically adjusted over the Advertised voltage range and limited by the Source to a programmable current limit.  SPR AVS and EPR AVS are used to expose a power supply whose output voltage can be adjusted over the Advertised voltage range but otherwise is equivalent to a Fixed Supply (AVS does not support a programmable current limit). Power Data Objects are also used to expose additional Capabilities that May be utilized, such as in the case of a Power Role Swap. A list of one or more Power Data Objects Shall be sent by the Source to convey its Capabilities. The Sink May then request one of these Capabilities by returning a Request Data Object that contains an index to a Power Data Object, to Negotiate a mutually agreeable Explicit Contract. Where Maximum and Minimum voltage and current values are given in PDOs these Shall be taken to be absolute values. The Source and Sink Shall Not Negotiate a power level that would allow the current to exceed the maximum current supported by their receptacles or the Attached plug (see [USB Type-C 2.4]). The Source Shall limit its offered Capabilities to the maximum current supported by its receptacle and Attached plug. A Sink Shall only make a request from any of the Capabilities offered by the Source. For further details see Section 4.4, "Cable Type Detection". Sources expose their power Capabilities by sending a Source_Capabilities Message. Sinks expose their power requirements by sending a Sink_Capabilities Message. Both are composed of several 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). Table 6.7 Power Data Object Bit(s) Description Value Parameter B31…30 00b Fixed Supply (Vmin = Vmax) 01b Battery 10b Variable Supply (non-Battery) 11b Augmented Power Data Object (APDO) B29…0 Specific Power Capabilities are described by the PDOs in the following sections. Page 140 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Augmented Power Data Object (APDO) is defined to allow support for more than the four PDO types by extending the Power Data Object field from 2 to 4 bits when the B31…B30 are 11b. The generic APDO structure is shown in Table 6.8, "Augmented Power Data Object". Table 6.8 Augmented Power Data Object Bit(s) Description Value Parameter B31…30 11b Augmented Power Data Object (APDO) B29…28 00b SPR PPS 01b EPR AVS 10b SPR AVS 11b Reserved B27…0 Specific Power Capabilities are described by the APDOs in the following sections. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 141 6.4.1.2 Source Power Data Objects This section lists the types of PDOs a Source can use in an SPR Capabilities or EPR Capabilities Message. 6.4.1.2.1 Fixed Supply Power Data Object Table 6.9, "Fixed Supply PDO – Source" describes the Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources"for the electrical requirements of the power supply. Since all USB Providers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29…23. All other Fixed Supply Power Data Objects Shall set bits 29…23 to zero. For a Source offering no Capabilities, the Voltage field (B19…10) Shall be set to 5V and theMaximum Current field Shall be set to 0mA. This is used in cases such as a Dual-Role Power device which offers no Capabilities in its default Power Role or when external power is required to offer power. When a Source wants a Sink, consuming power from VBUS, to go to its lowest power state, the Voltage field (B19…10) Shall be set to 5V and the Maximum Current field Shall be set to 0mA. This is used in cases where the Source wants the Sink to draw pSnkSusp. 6.4.1.2.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.2 USB Suspend Supported Prior to an Explicit Contract or when the USB Communications Capable bit is set to zero, the USB Suspend Supported flag is undefined and Sinks Shall follow the rules for suspend as defined in [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. After an Explicit Contract has been Negotiated:  If the USB Suspend Supported flag is set, then the Sink Shall follow the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and resume. A PDUSB Peripheral May draw up to pSnkSusp during suspend; a PDUSB Hub May draw up to pHubSusp during suspend (see Section 7.2.3, "Sink Standby"). Table 6.9 Fixed Supply PDO – Source Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ for Dual-Role Power device. B28 USB Suspend Supported Set to ‘1’ if USB suspend is supported. B27 Unconstrained Power Set to ‘1’ if unconstrained power is available. B26 USB Communications Capable Set to ‘1’ if capable of USB Communications capable B25 Dual-Role Data Set to ‘1’ for a Dual-Role Data device. B24 Unchunked Extended Messages Supported Set to ‘1 if Unchunked Extended Messages are supported. B23 EPR Capable Set to ‘1 if EPR Capable. B22 Reserved Reserved – Shall be set to zero. B21…20 Peak Current Peak Current value. B19…10 Voltage Voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 142 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the USB Suspend Supported flag is cleared, then the Sink Shall Not apply the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and May continue to draw the Negotiated power. Note: When USB is suspended, the USB device state is also suspended. Sinks May indicate to the Source that they would prefer to have the USB Suspend Supported flag cleared by setting the No USB Suspend flag in a Request Message (see Section 6.4.2.5, "No USB Suspend"). 6.4.1.2.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.2.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sources capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.2.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Data bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.1.2.1.7 EPR Mode Capable The EPR Capable bit is a Static bit that Shall be set if the Source is designed to supply more than 100W and operate in EPR Mode. When this bit is set, an EPR Source:  Operating in SPR Mode Shall only send an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Message  May only enter EPR Mode when the Cable and the Sink also report that they are EPR Capable. 6.4.1.2.1.8 Peak Current The USB Power Delivery Fixed Supply is only required to deliver the amount of current requested in the Operating Current field (IoC) of an RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current (see Section 7.2.8, "Sink Peak Current Operation") period needed to maintain such average power. The Peak Current field allows a Source to Advertise this additional capability. This capability is intended for direct Port to Port connections only and Shall Not be offered to downstream Sinks via a Hub. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 143 Every Fixed Supply PDO Shall contain a Peak Current field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current field in the corresponding Fixed Supply PDO (see Table 6.10, "Fixed Power Source Peak Current Capability"). Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding Fixed Supply PDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall also set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send the Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. 6.4.1.2.2 Variable Supply (non-Battery) Power Data Object Table 6.11, "Variable Supply (non-Battery) PDO – Source" describes a Variable Supply (non-Battery) (10b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall define the range that output voltage Shall fall within. This does not indicate the voltage that will be supplied, except it Shall fall within that range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. The Minimum Voltage field value Shall Not be less than 80% of the Maximum Voltage field value. 6.4.1.2.3 Battery Supply Power Data Object Table 6.12, "Battery Supply PDO – Source" describes a Battery Supply (01b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall represent the Battery's voltage range. The Battery Shall be capable of supplying the Power value over the entire voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: The Battery Supply PDO uses power instead of current. Table 6.10 Fixed Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Table 6.11 Variable Supply (non-Battery) PDO – Source Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 144 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Sink May monitor the Battery voltage. Table 6.12 Battery Supply PDO – Source Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Allowable Power Maximum allowable power in 250mW units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 145 6.4.1.2.4 Augmented Power Data Object (APDO) The voltage fields define the output voltage range over which the power supply Shall be adjustable in 20mV steps in SPR PPS Mode and 100mV steps in both SPR AVS Mode and EPR AVS Mode. The Maximum Current field contains the current the Programmable Power Supply Shall be capable of delivering over the Advertised voltage range. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. 6.4.1.2.4.1 SPR Programmable Power Supply APDO Table 6.13, "SPR Programmable Power Supply APDO – Source" below describes the SPR PPS (1100b) APDO for a Source operating in SPR Mode and supplying 5V up to 21V. The PPS APDO is used primarily for Sink Directed Charge Directed Charge of a Battery in the Sink. When applying a current to the Battery greater than the cable supports, a high efficiency fixed voltage scaler May be used in the Sink to reduce the cable current. 6.4.1.2.4.1.1 PPS Power Limited When the PPS Power Limited bit is set, the SPR PPS Source Shall operate in the same way as if the PPS Power Limited bit is clear (see Section 7.1.4.2, "SPR Programmable Power Supply (PPS)" with the below exception:  May supply power that exceeds the Source's rated PDP within the Optional operating area in Figure 7.7, "SPR PPS Constant Power". When the PPS Power Limited bit is cleared, the SPR PPS Source Shall deliver the Maximum Current field value up to the Maximum Voltage as Advertised in its APDO. The SPR PPS Source Shall Not reject an RDO with an Operating Current field value that is less than or equal to the Maximum Current field value in the APDO even if the requested Operating Current field value is greater than the Source's PDP/requested Output voltage. Table 6.13 SPR Programmable Power Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27 PPS Power Limited Set to ‘1’ when PPS Power Limited B26…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Page 146 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.2.4.2 SPR Adjustable Voltage Supply APDO Table 6.14, "SPR Adjustable Voltage Supply APDO – Source" below describes the SPR AVS (1110b) APDO for a Source operating in SPR Mode and supplying 9V up to 20V. 6.4.1.2.4.2.1 Peak Current The Peak Current field follows the same definition as for the Peak Current field (see Section 6.4.1.2.1.8, "Peak Current" and Table 6.10, "Fixed Power Source Peak Current Capability". 6.4.1.2.4.3 EPR Adjustable Voltage Supply APDO Table 6.15, "EPR Adjustable Voltage Supply APDO – Source" below describes the EPR AVS (1101b) APDO for a Source operating in EPR Mode and supplying 15V up to 48V. 6.4.1.2.4.3.1 PDP The PDP field Shall contain the AVS Port's PDP. See Section 10.2.3.3, "Optional Normative Extended Power Range (EPR)" and Figure 10.6, "Valid EPR AVS Operating Region" for more information regarding how PDP in the AVS APDO relates to maximum available current. 6.4.1.2.4.3.2 Peak Current The USB Power Delivery EPR AVS is only required to deliver the amount of current requested in the Operating Current field (IoC) of an AVS RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current period needed to maintain such average power (see Section 7.2.8, "Sink Peak Current Operation"). The Peak Current (Source EPR AVS) field allows a Source to Advertise this additional capability. This Table 6.14 SPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…26 Peak Current Peak Current (see Table 6.10, "Fixed Power Source Peak Current Capability")) B25…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the maximum voltage in the SPR AVS range is 15V. Table 6.15 EPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Peak Current (Source EPR AVS) Peak Current (see Table 6.16, "EPR AVS Power Source Peak Current Capability") B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 147 capability is intended for direct Port to Charger connections only and Shall Not be offered to downstream Sinks via a Hub. Every EPR AVS APDO Shall contain a Peak Current (Source EPR AVS) field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current (Source EPR AVS) field in the corresponding EPR AVS APDO (see Table 6.16, "EPR AVS Power Source Peak Current Capability". Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding EPR AVS APDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send a Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. Table 6.16 EPR AVS Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Page 148 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.3 Sink Power Data Objects This section lists the types of PDOs a Sink can use in an SPR or EPR Capabilities Message. 6.4.1.3.1 Sink Fixed Supply Power Data Object Table 6.17, "Fixed Supply PDO – Sink" describes the Sink Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Sink Shall set the Voltage field to its required voltage and the Operational Current field to its required operating current. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. Since all USB Consumers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29 through 20. All other Fixed Supply Power Data Objects Shall set bits 29…20 to zero. For a Sink requiring no power from the Source, the Voltage field Shall be set to 5V and the Operational Current field Shall be set to 0mA. 6.4.1.3.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.2 Higher Capability In the case that the Sink needs more than vSafe5V (e.g., 15V) to provide full functionality, then the Higher Capability bit Shall be set. 6.4.1.3.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. Table 6.17 Fixed Supply PDO – Sink Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ if Dual-Role Power supported B28 Higher Capability Set to ‘1’ if Higher Capability supported B27 Unconstrained Power Set to ‘1’ if Unconstrained Power supported B26 USB Communications Capable Set to ‘1’ if USB Communications Capable B25 Dual-Role Data Dual-Role Data B24...23 Fast Role Swap required USB Type-C Current Fast Role Swap required USB Type-C current (see also [USB Type-C 2.4]): Value Description 00b Fast Role Swap not supported (default) 01b Default USB Port 10b 1.5A@5V 11b 3.0A@5V B22...20 Reserved Reserved – Shall be set to zero. B19…10 Voltage Voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 149 To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.3.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sinks capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.3.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Dataa bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.6 Fast Role Swap USB Type-C Current The Fast Role Swap required USB Type-C Current field Shall indicate the current level the Sink will require after a Fast Role Swap has been performed. The Initial Source Shall Not transmit a Fast Role Swap Request if the Fast Role Swap required USB Type-C Current field is set to zero. Initially when the New Source applies vSafe5V it will have Rd asserted but Shall provide the USB Type-C current indicated by the New Sink in this field. If the New Source is not able to supply this level of current, it Shall Not perform a Fast Role Swap. When Rp is asserted by the New Source during the Fast Role Swap AMS (see Section 6.3.19, "FR_Swap Message"), the value of USB Type-C current indicated by Rp Shall be the same or greater than that indicated in the Fast Role Swap required USB Type-C Current field. 6.4.1.3.2 Variable Supply (non-Battery) Power Data Object Table 6.18, "Variable Supply (non-Battery) PDO – Sink" describes a Variable Supply (non-Battery) (10b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Current field Shall be set to the operational current that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.3 Battery Supply Power Data Object Table 6.19, "Battery Supply PDO – Sink" describes a Battery Supply (01b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. Table 6.18 Variable Supply (non-Battery) PDO – Sink Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Page 150 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Power field Shall be set to the operational power that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: Only the Battery Supply PDO uses power instead of current. Required operating power is defined as the amount of power a given device needs to be functional. This value could be the maximum power the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.4 Augmented Power Data Objects See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Maximum and Minimum voltage fields Shall be set to the output voltage range that the Sink requires to operate. 6.4.1.3.4.1 SPR Programmable Power Supply APDO Table 6.20, "SPR Programmable Power Supply APDO – Sink" below describes a SPR PPS APDO for a Sink operating in SPR Mode and consuming 21V or less. The Maximum Current field Shall be set to the maximum current the Sink requires over the voltage range. The maximum current is defined as the maximum amount of current the device needs to fully support its function (e.g., Sink Directed Charge). Table 6.19 Battery Supply PDO – Sink Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Power Operational Power in 250mW units Table 6.20 SPR Programmable Power Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 151 6.4.1.3.4.2 SPR Adjustable Voltage Supply APDO Table 6.21, "SPR Adjustable Voltage Supply APDO – Sink" below describes the SPR AVS (1110b) APDO for a Sink operating in SPR AVS Mode. The Maximum Current 15V/Maximum Current 20V fields in the SPR AVS APDO for the Sink is defined as the maximum current the device needs to fully support its function. 6.4.1.3.4.3 EPR Adjustable Voltage Supply APDO Table 6.22, "EPR Adjustable Voltage Supply APDO – Sink" below describes a EPR AVS APDO for a Sink operating in EPR AVS Mode. The PDP field in the EPR AVS APDO for the Sink is defined as the PDP the device needs to fully support its function. 6.4.1.4 SPR Capabilities Message Construction An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) Shall have at least one Power Data Object for vSafe5V. The SPR Capabilities Message Shall also contain the sending Port's information followed by up to 6 additional Power Data Objects. Power Data Objects in an SPR Capabilities Message Shall be sent in the following order: 1) The vSafe5V Fixed Supply PDO Shall always be the first (A)PDO. 2) The remaining Fixed Supply PDOs, if present, Shall be sent in voltage order; lowest to highest. 3) The Battery Supply PDOs if present Shall be sent in Minimum voltage order; lowest to highest. 4) The Variable Supply (non-Battery) PDOs, if present, Shall be sent in Minimum voltage order; lowest to highest. 5) The SPR AVS APDO, if present, Shall be sent. 6) The Programmable Power Supply APDOs, if present, Shall be sent in Maximum voltage order, lowest to highest. Note: The EPR Capabilities Message construction is defined in Section 6.5.15.1, "EPR Capabilities Message Construction". Table 6.21 SPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum Current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the Maximum voltage in the SPR AVS range is 15V. Table 6.22 EPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Reserved Reserved – Shall be set to zero. B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Page 152 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.12, "SPR Capabilities Message Construction" describes the construction of an SPR Capabilities Message. The Message will always have at least one Fixed Supply 5V PDO and may have up to six more PDOs depending on the Source Capabilities. Figure 6.12 SPR Capabilities Message Construction Figure 6.13 Example Capabilities Message with 2 Power Data Objects In the 27W Source as shown in Figure 6.13, "Example Capabilities Message with 2 Power Data Objects", the Number of Data Objects field is 2: vSafe5V plus one other voltage. Power Data Objects (PDO) and Augmented Power Data Objects (APDO) are identified by the Message Header's Message Type field. They are used to form SPR Capabilities Messages. 6.4.1.5 SPR Source Capabilities Message Sources send a Source_Capabilities Message either as part of advertising Port Capabilities, or in response to a Get_Source_Cap Message. See Section 6.5.15.2, "EPR_Source_Capabilities Message" for information about EPR Source Capabilities Messages. Following a Hard Reset, a power-on event or plug insertion event, a Source Port Shall send a Source_Capabilities Message after every SourceCapabilityTimer timeout as an Advertisements that Shall be interpreted by the Sink Port on Attachment. The Source Shall continue sending a minimum of nCapsCount Source_Capabilities Messages until a GoodCRC Message is received. Additionally, a Source_Capabilities Message Shall only be sent by a Port in the following cases:  By the Source Port from the PE_SRC_Ready state upon a change in its ability to supply power to this Port.  By a Source Port or Dual-Role Power Port in response to a Get_Source_Cap Message.  Optionally by a Source Port from the PE_SRC_Ready state when available power in a multi-Port system changes, even if the Source Capabilities for this Port have not changed. A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual- Role Power ports presently operating as a Sink. Each Power Data Object Shall describe a specific Source capability such as a Battery (e.g., 2.8-4.1V) or a Fixed Supply (e.g., 15V) at a maximum allowable current. The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sources Shall minimally offer one Power Data Object that reports vSafe5V. A Source Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Source capability and voltage. Header 2 bytes PDO 1 PDO 2 PDO 3 PDO 4 PDO 5 PDO 6 PDO 7 001b 010b 011b 100b 101b 110b 111b Header No. of Data Objects = 2 Fixed 5V PDO Fixed 9V PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 153 Sinks with Accessory Support do not source VBUS (see [USB Type-C 2.4]). Sinks with Accessory Support are still considered Sources when sourcing VCONN to an Accessory even though VBUS is not applied; in this case they Shall Advertise vSafe5V with the Maximum Current field set to 0mA in the first Power Data Object. The main purpose of this is to enable the Sink with Accessory Support to get into the PE_SRC_Ready State to enter an Alternate Mode. A Sink in SPR Mode Shall evaluate every Source_Capabilities Message it receives and Shall respond with a Request Message. If its power consumption exceeds the Source Capabilities it Shall Re-negotiate so as not to exceed the Source's most recently Advertised Capabilities. A Sink, in SPR Mode, in an Explicit Contract with a PPS APDO, Shall periodically re-request the PPS APDO at least every tPPSRequest until either:  The Sink requests something other than PPS APDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. A Sink in EPR Mode that receives a Source_Capabilities Message in response to a Get_Source_Cap Message Shall Not respond with a Request Message. If a Sink in EPR Mode receives a Source_Capabilities Message, not in response to a Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. A Source that has accepted a Request Message with a Programmable RDO Shall issue Hard Reset Signaling if it has not received a Request Message with a Programmable RDO within tPPSTimeout. The Source Shall discontinue this behavior after:  Receiving a Request Message with a Fixed Supply, Variable Supply or Battery Supply RDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. 6.4.1.6 SPR Sink Capabilities Message Sinks send a Sink_Capabilities Message (see Section 6.4.2, "Request Message") in response to a Get_Sink_Cap Message. See Section 6.5.15.3, "EPR_Sink_Capabilities Message" for more information about the Capabilities Message. A USB Power Delivery capable Sink, upon detecting vSafe5V on VBUS and after a SinkWaitCapTimer timeout without seeing a Source_Capabilities Message, Shall send a Hard Reset. If the Attached Source is USB Power Delivery capable, it responds by sending Source_Capabilities Messages thus allowing power Negotiations to begin. A Sink Port Shall report power levels it is able to operate at in a series of 32-bit Power Data Objects (see Section Table 6.7, "Power Data Object"). These are returned as part of a Sink_Capabilities Message in response to a Get_Sink_Cap Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). This is similar to that used for Source Port Capabilities with equivalent Power Data Objects for Fixed Supply, Variable Supply and Battery Supply as defined in this section. Power Data Objects are used to convey the Sink Port's operational power requirements including Dual-Role Power Ports presently operating as a Source. Each Power Data Object Shall describe a specific Sink operational power level, such as a Battery Supply (e.g., 2.8- 4.1V) or a Fixed Supply (e.g., 15V). The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sinks Shall minimally offer one Power Data Object with a power level at which the Sink can operate. A Sink Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Sink capability and voltage. All Sinks Shall include one Power Data Object that reports vSafe5V even if they require additional power to operate fully. In the case where additional power is required for full operation the Higher Capability bit Shall be set. Page 154 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.6.1 Use by Dual-Role Power devices Dual-Role Power devices send a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message") as part of advertising Port Capabilities when operating in Source role. Dual-Role Power devices send a Source_Capabilities Message in response to a Get_Source_Cap Message regardless of their present operating role. Similarly Dual-Role Power devices send a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message") in response to a Get_Sink_Cap Message regardless of their present operating role. 6.4.1.6.2 Management of the Power Reserve This section has been removed. Refer to Section 8.2.5, "Managing Power Requirements". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 155 6.4.2 Request Message A Request Message Shall be sent by a Sink to request power during the request phase of an SPR power Negotiation. The Request Data Object Shall be returned by the Sink making a request for power. It Shall be sent in response to the most recent Source_Capabilities Message (see Section 8.3.2.2, "Power Negotiation") when in SPR Mode. A Request Message Shall return one and only one Sink Request Data Object that Shall identify the Power Data Object being requested. The Source Shall respond to a Request Message with an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Request Message includes the requested power level. For example, if the Source_Capabilities Message includes a Fixed Supply PDO that offers 9V @ 1.5A and if the Sink only wants 9V @ 0.5A, it will set the Operating Current field to 50 (i.e., 10mA * 50 = 0.5A). The request uses a different format depending on the kind of power requested.  The Fixed Supply Power Data Object and Variable Supply Power Data Object share a common format shown in Table 6.23, "Fixed and Variable Request Data Object".  The Battery Supply Power Data Object uses the format shown in Table 6.24, "Battery Request Data Object".  The PPS Request Data Object's format is shown in Table 6.25, "PPS Request Data Object".  The AVS Request Data Object's format is shown in Table 6.26, "AVS Request Data Object". The Request Data Objects are also used by the EPR_Request Message when operating in EPR Mode. See Section 6.4.9, "EPR_Request Message" for information about the use of the EPR_Request Message. A Source operating in EPR Mode that receives a Request Message Shall initiate a Hard Reset. Table 6.23 Fixed and Variable Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0 - Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Current Operating current in 10mA units B9…0 Maximum Operating Current Maximum Operating current 10mA units Page 156 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.24 Battery Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0- Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Power Operating Power in 250mW units B9…0 Maximum Operating Power Maximum Operating Power in 250mW units Table 6.25 PPS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 20mV units. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Table 6.26 AVS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 25mV units, the least two significant bits Shall be set to zero making the effective voltage step size 100mV. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 157 6.4.2.1 Object Position The value in the Object Position field Shall indicate which object in the Source_Capabilities Message or EPR_Source_Capabilities Message the RDO refers to. The value 0001b always indicates the 5V Fixed Supply PDO as it is the first object following the Source_Capabilities Message’s Message Header or EPR_Source_Capabilities Message’s Extended Message Header. The number 0010b refers to the next PDO and so forth. The Object Position field values 0001b…0111b Shall only be used to refer to SPR (A)PDOs. SPR (A)PDOs May be requested by either a Request or an EPR_Request Message. Object positions 1000b…1011b Shall only be used to refer to EPR (A)PDOs. EPR (A)PDOs Shall only be requested by an EPR_Request Message. If the Object Position field in a Request Message contains a value greater than 0111b, the Source Shall send Hard Reset Signaling. 6.4.2.2 GiveBack Flag (Deprecated) The Giveback flag has been Deprecated and Shall be set to zero. 6.4.2.3 Capability Mismatch A Capabilities Mismatch occurs when the Source cannot satisfy the Sink's power requirements based on the Source Capabilities it has offered. In this case the Sink Shall make a Valid request from the offered Source Capabilities and Shall set the Capability Mismatch bit (see Section 8.2.5.2, "Power Capability Mismatch"). When a Capabilities Mismatch condition does not exist, the Sink Shall Not set the Capability Mismatch bit. When a Sink returns a Request Data Object with the Capability Mismatch bit set in response to a Source Capabilities Message, it indicates that it wants more power than the Source is currently offering. This can be due to either a specific voltage that is not being offered or there is not sufficient current for the voltages that are being offered. Sources whose Port Reported PDP is less than their Port Present PDP (see Section 6.4.11, "Source_Info Message") Shall respond to the Requests with the Capability Mismatch bit set as follows. The Source within tCapabilitiesMismatchResponse of the PS_RDY Message Shall send a new Source Capabilities Message that offers either: 1) The set of Source Capabilities to minimally satisfy the Sink's requirements based on what it actually requires for full operation by evaluating the: a) Sink_Capabilities_Extended Message(if supported by the Sink) and/or b) Sink_Capabilities or EPR_Sink_Capabilities Message. 2) The set of Source Capabilities the Source can supply at this time based on the Port Present PDP. To prevent looping, Sources Should Not send a new Source Capabilities Message in response to subsequent Request Message with the Capability Mismatch flag set until its Port Present PDP changes. Once a Guaranteed Capability Source that has responded to a Capability Mismatch, it Shall Not subsequently send out another Source Capabilities Message at a lower PDP unless the power required by the Sink (as indicated in its Sink Capabilities Message or Sink_Capabilities_Extended Message) has also been reduced. Sources wishing to manage their power May periodically check the Sink Capabilities Message or Sink_Capabilities_Extended Message to determine whether these have changed. Note: A Source Capabilities Message refers to a Source_Capabilities Message or an EPR_Source_Capabilities Message, and a Sink Capabilities Message refers to a Sink_Capabilities Message or EPR_Sink_Capabilities Message, Request refers to a Request Message or EPR_Request depending on operating mode. In this context a Valid Request Message means the following:  The Object Position field Shall contain a reference to an object that was present in the last received Source Capabilities Message.  The Operating Current/Operating Power field Shall contain a value which is less than or equal to the maximum current/power offered by the selected (A)PDO the Source Capabilities Message. Page 158 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.2.4 USB Communications Capable The USB Communications Capable flag Shall be set to one when the Sink has USB data lines and is capable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. The USB Communications Capable flag Shall be set to zero when the Sink does not have USB data lines or is otherwise incapable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. This is used by the Source to determine operation in certain cases such as USB suspend. If the USB Communications Capable flag has been set to zero by a Sink, then the Source needs to be aware that USB Suspend rules cannot be observed by the Sink. 6.4.2.5 No USB Suspend The No USB Suspend flag May be set by the Sink to indicate to the Source that this device is requesting to continue its Explicit Contract during USB Suspend. Sinks setting this flag typically have functionality that can use power for purposes other than USB Communication e.g., for charging a Battery. The Source uses this flag to evaluate whether it Should re-issue the Source_Capabilities Message with the USB Suspend Supported flag cleared. 6.4.2.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.2.7 EPR Mode Capable The EPR Capable bit Shall indicate whether or not the Sink is capable of operating in EPR Mode. When the Sink's ability to operate in EPR Mode changes, it Shall send a new Request Message with the updated EPR Capable bit set in the RDO. 6.4.2.8 Operating Current The Operating Current field in the Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. A new Request Message or EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The Operating Current field in the SPR Programmable Request Data Object is used in addition by the Sink to request the Source for the Current Limit level it needs. When the request is accepted the Source's output current supplied into any load Shall be less than or equal to the Operating Current value. When the Sink attempts to consume more current, the Source Shall reduce the output voltage so as not to exceed the Operating Current value. The Operating Current field in the AVS Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. Note: A Source in AVS Mode, unlike the SPR Source in PPS Mode, does not support current limit; the Sink is responsible not to take more current than it requested. A new Request / EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The value in the Operating Current field Shall Not exceed the value in the Maximum Current field of the Source_Capabilities Message. For EPR AVS, the Operating Current field Shall Not exceed the PDP / Output voltage rounded down to the nearest 50 mA. This field Shall apply to the Fixed Supply, Variable Supply, Programmable and AVS RDOs. 6.4.2.9 Maximum Operating Current The Maximum Operating Current field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Current field in the Request Message or EPR_Request Message, the field Shall be set equal to the value of the Operating Current field. To ensure backward compatibility, the Source Should Ignore this field. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 159 This field Shall apply to the Fixed Supply and Variable Supply RDO in SPR Mode and the Fixed Supply RDO in EPR Capable. 6.4.2.10 Operating Power The Operating Power field in the Request Data Object Shall be set to the highest power the Sink will draw throughout the Explicit Contract. This field Shall apply to the Battery Supply RDO. 6.4.2.11 Maximum Operating Power The Maximum Operating Power field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Power field in the Request Message, the field Shall be set equal to the value of the Operating Power field. To ensure backward compatibility, the Source Should Ignore this field. This field Shall apply to the Battery Supply RDO. 6.4.2.12 Output Voltage The Output Voltage field in the Programmable and AVS Request Data Objects Shall be set by the Sink to the voltage the Sink requires as measured at the Source's output connector. The Output Voltage field Shall be greater than or equal to the Minimum Voltage field and less than or equal to the Maximum Voltage field in the Programmable Power Supply and AVS APDOs, respectively. This field Shall apply to the Programmable RDO and AVS RDO. 6.4.3 BIST Message The BIST Message is sent to request the Port to enter a PHY Layer test mode (see Section 5.9, "Built in Self-Test (BIST)") that performs one of the following functions:  Enter a Continuous BIST Mode to send a continuous stream of test data to the Tester.  Enter and leave a Shared Capacity Group test mode. The Message format is as shown in Figure 6.14, "BIST Message". Figure 6.14 BIST Message All Ports Shall be able to be a Unit Under Test (UUT) only when operating at vSafe5V. All of the following BIST Modes Shall be supported:  Process reception of a BIST Carrier Mode BIST Data Object that Shall result in the generation of the appropriate carrier signal.  Process reception of a BIST Test Data BIST Data Object that Shall result in the Message being Ignored. UUTs with Ports constituting a Shared Capacity Group (see [USB Type-C 2.4]) Shall support the following BIST Mode:  Process reception of a BIST Shared Test Mode Entry BIST Data Object that Shall cause the UUT to enter BIST Shared Capacity Test Mode; a mode in which the UUT offers its full Source Capabilities on every Port in the Shared Capacity Group. Header No. of Data Objects = 1 or 7 BIST Data Object Page 160 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Process reception of a BIST Shared Test Mode Exit BIST Data Object that Shall cause the UUT to exit the BIST Shared Capacity Test Mode. When a Port receives a BIST Message BIST Data Object for a BIST Mode when not operating at vSafe5V, the BIST Message Shall be Ignored. When a Port receives a BIST Message BIST Data Object for a BIST Mode it does not support the BIST Message Shall be Ignored. When a Port or Cable Plug receives a BIST Message BIST Data Object for a Continuous BIST Mode the Port or Cable Plug enters the requested BIST Mode and Shall remain in that BIST Mode for tBISTContMode and then Shall return to normal operation (see Section 6.6.7.2, "BISTContModeTimer"). The usage model of the PHY Layer BIST Modes generally assumes that some controlling agent will request a test of its Port Partner. In Section 8.3.2.15, "Built in Self-Test (BIST)" there is a sequence description of the test sequences used for compliance testing. The fields in the BIST Data Object are defined in the Table 6.27, "BIST Data Object". 6.4.3.1 BIST Carrier Mode Upon receipt of a BIST Message, with a BIST Carrier Mode BIST Data Object, the UUT Shall send out a continuous string of BMC encoded alternating "1"s and "0"s. The UUT Shall exit the Continuous BIST Mode within tBISTContMode of this Continuous BIST Mode being enabled (see Section 6.6.7.2, "BISTContModeTimer"). 6.4.3.2 BIST Test Data Mode Upon receipt of a BIST Message, with a BIST Test Data BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter BIST Test Data Mode in which it sends no further Messages except for GoodCRC Messages in response to received Messages. See Section 5.9.2, "BIST Test Data Mode" for the definition of the Test Frame. The test Shall be ended by sending Hard Reset Signaling to reset the UUT. Table 6.27 BIST Data Object Bit(s) Value Parameter Description Reference Applicability B31…28 0000b…0100b Reserved Shall Not be used Section 1.4.2 - 0101b BIST Carrier Mode Request Transmitter to enter BIST Carrier Mode Section 6.4.3.1 Mandatory 0110b…0111b Reserved Shall Not be used Section 1.4.2 - 1000b BIST Test Data Sends a Test Frame. Section 6.4.3.2 Mandatory 1001b BIST Shared Test Mode Entry Requests UUT to enter BIST Shared Capacity Test Mode. Section 6.4.3.3.1 Mandatory for UUTs with shared capacity 1010b BIST Shared Test Mode Exit Requests UUT to exit BIST Shared Capacity Test Mode. Section 6.4.3.3.2 Mandatory for UUTs with shared capacity 1011b…1111b Reserved Shall Not be used Section 1.4.2 - B27…0 Reserved Shall be set to zero. Section 1.4.2 - Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 161 6.4.3.3 BIST Shared Capacity Test Mode A Shared Capacity Group of Ports share a common power source that is not capable of simultaneously powering all the ports to their full Source Capabilities (see [USB Type-C 2.4]). The BIST Shared Capacity Test Mode Shall only be implemented by ports in a Shared Capacity Group. The UUT Shared Capacity Group of Ports Shall contain one or more Ports, designated as Master Ports, that recognize both the BIST Shared Test Mode Entry BIST Data Object and the BIST Shared Test Mode Exit BIST Data Object. 6.4.3.3.1 BIST Shared Test Mode Entry When any master Port in a Shared Capacity Group receives a BIST Message with a BIST Shared Test Mode Entry BIST Data Object, while in the PE_SRC_Ready State, the UUT Shall enter a compliance test mode where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. Ports in the Shared Capacity Group that are not Master Ports Shall Not enter compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Upon receipt of a BIST Message, with a BIST Shared Test Mode Entry BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter the BIST Shared Capacity Test Mode. On entering this mode, the UUT Shall send a new Source_Capabilities Message from each Port in the Shared Capacity Group within tBISTSharedTestMode. The Tester will not exceed the shared capacity during this mode. 6.4.3.3.2 BIST Shared Test Mode Exit Upon receipt of a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, the UUT Shall return a GoodCRC Message and Shall exit the BIST Shared Capacity Test Mode. If any other Message, aside from a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, is received while in BIST Shared Capacity Test Mode this Shall Not cause the UUT to exit the BIST Shared Capacity Test Mode On exiting the mode, the UUT May send a new Source_Capabilities Message to each Port in the Shared Capacity Group or the UUT May perform ErrorRecovery on each Port. Ports in the Shared Capacity Group that are not Master Ports Shall Not exit compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Ports in the Shared Capacity Group that are not Master Ports Should Not exit compliance mode on receiving the BIST Shared Test Mode Exit BIST Data Object.  The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off.  The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs:  Hard Reset  Cable Reset  Soft Reset  Data Role Swap  Power Role Swap  Fast Role Swap  VCONN Swap.  The UUT May leave BIST Shared Capacity Test Mode if the Tester makes a request that exceeds the Capabilities of the UUT. Page 162 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4 Vendor Defined Message The Vendor_Defined Message (VDM) is provided to allow vendors to exchange information outside of that defined by this specification. A Vendor_Defined Message Shall consist of at least one Vendor Data Object (VDO), the VDM Header, and May contain up to a maximum of six additional VDOs. To ensure vendor uniqueness of Vendor_Defined Messages, all Vendor_Defined Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. Two types of Vendor_Defined Messages are defined: Structured VDMs and Unstructured VDMs. A Structured VDM defines an extensible structure designed to support Modal Operation. An Unstructured VDM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. The Message format Shall be as shown in Figure 6.15, "Vendor Defined Message". Figure 6.15 Vendor Defined Message The VDM Header Shall be the first 4-byte object in a Vendor Defined Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. Additionally, vendors May make use of the Commands in a Structured VDM. The fields in the VDM Header for an Unstructured VDM, when the VDM Type Bit is set to zero, Shall be as defined in Table 6.28, "Unstructured VDM Header". The fields in the VDM Header for a Structured VDM, when the VDM Type Bit is set to one Shall be as defined in Table 6.29, "Structured VDM Header". Both Unstructured VDMs and Structured VDMs Shall only be sent and received after an Explicit Contract has been established. The only exception to this is the Discover Identity Command which May be sent by Source when a Default Contract or an Implicit Contract (in place after Attach, a Power Role Swap or Fast Role Swap) is in place in order to discover Cable Capabilities (see SSection 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 6.4.4.1 Unstructured VDM The Unstructured VDM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the VID. The Port Partners and Cable Plugs Shall exit any states entered using an Unstructured VDM when a Hard Reset appears on PD. The following rules apply to the use of Unstructured VDM Messages:  Unstructured VDMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract Unstructured VDMs Shall Not be sent and Shall be Ignored if received.  Only the DFP Shall be an Initiator of Unstructured VDMs.  Only the UFP or a Cable Plug Shall be a Responder to Unstructured VDM.  Unstructured VDMs Shall Not be initiated or responded to under any other circumstances. Header No. of Data Objects = 1-7 VDM Header 0-6 VDOs Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 163  Unstructured VDMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can Unstructured VDMs be sent or received. The Active Mode and the associated Unstructured VDMs Shall use the same SVID.  Unstructured VDMs May be used with SOP* Packets.  When a DFP or UFP does not support Unstructured VDMs or does not recognize the VID it Shall return a Not_Supported Message. Table 6.28, "Unstructured VDM Header" illustrates the VDM Header bits. 6.4.4.1.1 USB Vendor ID The Vendor ID (VID) field Shall contain the 16-bit Vendor ID value assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. 6.4.4.1.2 VDM Type The VDM Type field Shall be set to zero indicating that this is an Unstructured VDM. 6.4.4.2 Structured VDM Setting the VDM Type field to 1 (Structured VDM) defines the use of bits B14…0 in the Structured VDM Header. The fields in the Structured VDM Header are defined in Table 6.29, "Structured VDM Header". The following rules apply to the use of Structured VDM Messages:  Structured VDMs Shall only be used when an Explicit Contract is in place with the following exception:  Prior to establishing the First Explicit Contract, a Source May issue Discover Identity Messages, to a Cable Plug using SOP’ Packets, as an Initiator (see Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram").  Either Port May be an Initiator of Structured VDMs except for the Enter Mode and Exit Mode Commands which Shall only be initiated by the DFP.  A Cable Plug Shall only be a Responder to Structured VDMs.  Structured VDMs Shall Not be initiated or responded to under any other circumstances.  When a DFP or UFP does not support Structured VDMs any Structured VDMs received Shall return a Not_Supported Message.  When using any of the SVID Specific Commands in the Structured VDM Header (VDM Header b4…0 - value 16 - 31) the Responder Shall NAK Messages where the SVID in the VDM Header is not recognized as an SVID that uses SVID Specific Commands or the use of SVID Specific Commands is not supported for the SVID.  When a Cable Plug does not support Structured VDMs any Structured VDMs received Shall be Ignored. Table 6.28 Unstructured VDM Header Bit(s) Parameter Description B31…16 Vendor ID (VID) Unique 16-bit unsigned integer. Assigned by the USB-IF to the Vendor. B15 VDM Type 0 = Unstructured VDM B14…0 Available for Vendor Use Content of this field is defined by the vendor. Page 164 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A DFP, UFP or Cable Plug which supports Structured VDMs and receiving a Structured VDM for a SVID that it does not recognize Shall reply with a NAK Command. Table 6.29 Structured VDM Header Bit(s) Field Description B31…16 Standard or Vendor ID (SVID) Unique 16-bit unsigned integer, assigned by the USB-IF B15 VDM Type 1 = Structured VDM B14…13 Structured VDM Version (Major) Version Number (Major) of the Structured VDM (not this specification Version):  Version 1.0 = 00b (Deprecated and Shall Not be used)  Version 2.x = 01b  Values 2-3 are Reserved and Shall Not be used B12…11 Structured VDM Version (Minor) For Commands 0…15 Version Number (Minor) of the Structured VDM  Version 2.0 = 00b (Used for ports implemented prior to USB PD Revision 3.1, Version 1.6)  Version 2.1 = 01b (Used for ports implemented starting with USB PD Revision 3.1, Version 1.6)  All other Values are Reserved and Shall Not be used  SVID Specific Commands (16…31) defined by the SVID. B10…8 Object Position For the Enter Mode, Exit Mode, and Attention Commands (Requests/ Responses):  000b = Reserved and Shall Not be used.  001b…110b = Index into the list of VDOs to identify the desired Alternate Mode VDO  111b = Exit all Active Modes (equivalent of a power on reset). Shall  only be used with the Command. Commands 0…3, 7…15:  000b  001b…111b = Reserved and Shall Not be used. SVID Specific Commands (16…31) defined by the SVID. B7…6 Command Type 00b = REQ (Request from Initiator Port) 01b = ACK (Acknowledge Response from Responder Port) 10b = NAK (Negative Acknowledge Response from Responder Port) 11b = BUSY (Busy Response from Responder Port) B5 Reserved Shall be set to zero and Shall be Ignored B4…01 Command 0 = Reserved and Shall Not be used. 1 = Discover Identity 2 = Discover SVIDs 3 = Discover Modes 4 = Enter Mode 5 = Exit Mode 6 = Attention 7-15 = Reserved and Shall Not be used. 16…31 = SVID Specific Commands 1) In the case where a SID is used the modes are defined by a standard. When a VID is used the modes are defined by the Vendor. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 165 Section Table 6.30, "Structured VDM Commands" shows the Commands, which SVID to use with each Command and the SOP* values which Shall be used. 6.4.4.2.1 SVID The Standard or Vendor ID (SVID) field Shall contain either a 16-bit USB Standard ID value (SID) or the 16-bit assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. Section Table 6.31, "SVID Values" lists specific SVID values referenced by this specification. 6.4.4.2.2 VDM Type The VDM Type field Shall be set to one indicating that this is a Structured VDM. 6.4.4.2.3 Structured VDM Version The Structured VDM Version (Major)/Structured VDM Version (Minor) fields indicate the level of functionality supported in the Structured VDM part of the specification. This is not the same Version as the Version of this specification. The Structured VDM Version (Major) Shall be set to 01b to indicate Version 2.x with the Structured VDM Version (Minor) field set as appropriate based on whether the Port is implemented to USB PD Revision 3.1, Version 1.6 (or newer) or a prior Version. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every Structured VDM Version number starting from Version 1.0. On receipt of a VDM Header with a higher Version number than it supports, a Port or Cable Plug Shall respond using the highest Version number it supports. On receipt of a VDM Header with a lower Version number than it supports, a Port or Cable Plug Shall respond using the same Version number it received. The Structured VDM Version (Major)/Structured VDM Version (Minor) fields of the Discover Identity Command sent and received during the Discovery Process Shall be used to determine the lowest common Structured VDM Version supported by the Port Partners or Cable Plug and Shall continue to operate using this Specification Revision until they are Detached. After discovering the Structured VDM Version, the Structured VDM Version (Major)/ Structured VDM Version (Minor) fields Shall match the agreed common Structured VDM Version. Table 6.30 Structured VDM Commands Command VDM Header SVID Field SOP* used Discover Identity Shall only use the PD SID. Shall only use SOP/SOP’. Discover SVIDs Shall only use the PD SID. Shall only use SOP/SOP’. Discover Modes Valid with any SVID. Shall only use SOP/SOP’. Enter Mode Valid with any SVID. Valid with SOP*. Exit Mode Valid with any SVID. Valid with SOP*. Attention Valid with any SVID. Valid with SOP*. SVID Specific Commands Valid with any SVID. Valid with SOP* (defined by SVID). Table 6.31 SVID Values Parameter Value Description PD SID 0xFF00 Standard ID allocated to this specification by USB-IF. DPTC SID 0xFF01 Standard ID allocated to [DPTC2.1] by USB-IF. Page 166 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.2.4 Object Position The Object Position field Shall be used by the Enter Mode and Exit Mode Commands. The Discover Modes Command returns a list of zero to six VDOs, each of which describes an Alternate Mode. The value in Object Position field is an index into that list that indicates which VDO (e.g., Alternate Mode) in the list the Enter Mode and Exit Mode Command refers to. The Object Position Shall start with one for the first Alternate Mode in the list. If the SVID is a VID, the content of the VDO for the Alternate Mode Shall be defined by the vendor. If the Standard or Vendor ID (SVID) is a SID, the value Shall be assigned, by the USB-IF, to the given Standard. The VDO's content May be as simple as a numeric value or as complex as bit mapped description of Capabilities of the Alternate Mode. In all cases, the Responder is responsible for deciphering the contents to know whether or not it supports the Alternate Mode at the Object Position. This field Shall be set to zero in the Request or Response (REQ, ACK, NAK or BUSY) when not required by the specification of the individual Command. 6.4.4.2.5 Command Type 6.4.4.2.5.1 Commands other than Attention This Command Type field Shall be used to indicate the type of Command request/response being sent. An Initiator Shall set the Command Type field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then the responses are as follows:  "Responder ACK" is the normal return and Shall be sent to indicate that the Command request was received and handled normally.  "Responder NAK" Shall be returned when the Command request:  Has an Invalid parameter (e.g., Invalid SVID or Alternate Mode).  Cannot be acted upon because the configuration is not correct (e.g., an Alternate Mode which has a dependency on another Alternate Mode or a request to exit an Alternate Mode which is not anActive Mode).  Is an Unrecognized Message.  The handling of "Responder NAK" is left up to the Initiator.  "Responder BUSY" Shall be sent in the response to a VDM when the Responder is unable to respond to the Command request immediately, but the Command request May be retried. The Initiator Shall wait tVDMBusy after a "Responder BUSY" response is received before retrying the Command request. 6.4.4.2.5.2 Attention Command This Command Type field Shall be used to indicate the type of Command request being sent. An Initiator Shall set the field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then no response Shall be made to an Attention Command. 6.4.4.2.6 Command 6.4.4.2.6.1 Commands other than Attention The Command field contains the value for the VDM Command being sent. The Commands explicitly listed in the Command field are used to identify devices and manage their operational Modes. There is a further range of Command values left for the vendor to use to manage additional extensions. A Structured VDM Command consists of a Command request and a Command response (ACK, NAK or BUSY). A Structured VDM Command is deemed to be completed (and if applicable, the transition to the requested functionality is made) when the GoodCRC Message has been successfully received by the Responder in reply to its Command response. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 167 If Structured VDMs are supported, but the Structured VDM Command request is an Unrecognized Message, it Shall be NAKed (see Table 6.32, "Commands and Responses"). 6.4.4.2.6.2 Attention Command The Command field contains the value for the VDM Command being sent (Attention). The Attention Command May be used by the Initiator to notify the Responder that it requires service. A Structured VDM Attention Command consists of a Command request but no Command response. A Structured VDM Attention Command is deemed to be completed when the GoodCRC Message has been successfully received by the Initiator in reply to its Attention Command request. If Structured VDMs are supported, but the Structured VDM Attention Command request is an Unrecognized Message it Shall be Ignored (see Table 6.32, "Commands and Responses"). 6.4.4.3 Use of Commands The VDM Header for a Structured VDM Message defines Commands used to retrieve a list of SVIDs the device supports, to discover the Modes associated with each SVID, and to enter/exit the Modes. The Commands include:  Discover Identity  Discover SVIDs  Discover Modes  Enter Mode  Exit Mode  Attention Additional Command space is also Reserved for Standard and Vendor use and for future extensions. The Command AMSs use the terms Initiator and Responder to identify messaging roles the ports are taking on relative to each other. This role is independent of the Port's power capability (Provider, Consumer etc.) or its present Power Role (Source or Sink). The Initiator is the Port sending the initial Command request and the Responder is the Port replying with the Command response. See Section 6.4.4.4, "Command Processes". All Ports that support Modes Shall support the Discover Identity, Discover SVIDs, the Discover Modes, the Enter Mode and Exit Mode Commands. Table 6.32, "Commands and Responses" details the responses a Responder May issue to each Command request. Responses not listed for a given Command Shall Not be sent by a Responder. A NAK response Should be taken as an indication not to retry that particular Command. Examples of Command usage can be found in Appendix C, "VDM Command Examples". Table 6.32 Commands and Responses Command Allowed Response Reference Discover Identity ACK, NAK, BUSY Section 6.4.4.3.1 Discover SVIDs ACK, NAK, BUSY Section 6.4.4.3.2 Discover Modes ACK, NAK, BUSY Section 6.4.4.3.3 Enter Mode ACK, NAK Section 6.4.4.3.4 Exit Mode ACK, NAK Section 6.4.4.3.5 Attention None Section 6.4.4.3.6 Page 168 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1 Discover Identity The Discover Identity Command is provided to enable an Initiator to identify its Port Partner and for an Initiator (VCONN Source) to identify the Responder (Cable Plug or VPD). The Discover Identity Command is also used to determine whether a Cable Plug or VPD is PD-Capable by looking for a GoodCRC Message Response. The Discover Identity Command Shall only be sent to SOP when there is an Explicit Contract. The Discover Identity Command Shall be used to determine whether a given Cable Plug or VPD is PD Capable (see Section 8.3.3.21.1, "Initiator Structured VDM Discover Identity State Diagram" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). In this case a Discover Identity Command request sent to SOP’ Shall Not cause a Soft Reset if a GoodCRC Message response is not returned since this can indicate a non-PD Capable cable or VPD. Note: A Cable Plug or VPD will not be ready for PD Communication until tVCONNStable after VCONN has been applied (see [USB Type-C 2.4]). During Cable Plug or VPD discovery, when there is an Explicit Contract, Discover Identity Commands are sent at a rate defined by the DiscoverIdentityTimer (see Section 6.6.15, "DiscoverIdentityTimer") up to a maximum of nDiscoverIdentityCount times (see Section 6.7.5, "Discover Identity Counter"). A PD-Capable Cable Plug or VPD Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP’. The Discover Identity Command Shall be used to determine the identity and/or Capabilities of the Port Partner. The following products Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP:  A PD-Capable UFP that supports Modal Operation.  A PD-Capable product that has multiple DFPs.  A PD-Capable [USB4] product. The SVID in the Discover Identity Command request Shall be set to the PD SID (see Section Table 6.31, "SVID Values"). The Number of Data Objects field in the Message Header in the Discover Identity Command request Shall be set to 1 since the Discover Identity Command request Shall Not contain any VDOs. The Discover Identity Command ACK sent back by the Responder Shall contain an ID Header VDO, a Cert Stat VDO, a Product VDO and the Product Type VDOs defined by the Product Type as shown in Figure 6.16, "Discover Identity Command response". This specification defines the following Product Type VDOs:  Passive Cable VDO (see Section 6.4.4.3.1.6, "Passive Cable VDO")  Active Cable VDOs (see Section 6.4.4.3.1.7, "Active Cable VDOs")  VCONN Powered USB Device (VPD) VDO (see Section 6.4.4.3.1.9, "VCONN Powered USB Device VDO")  UFP VDO (see Section 6.4.4.3.1.4, "UFP VDO")  DFP VDO (see Section 6.4.4.3.1.5, "DFP VDO") No VDOs other than those defined in this specification Shall be sent as part of the Discover Identity Command response. Where there is no Product Type VDO defined for a specific Product Type, no VDOs Shall be sent as part of the Discover Identity Command response. Any additional VDOs received by the Initiator Shall be Ignored. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 169 Figure 6.16 Discover Identity Command response The Number of Data Objects field in the Message Header in the Discover Identity Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the product is a DRD both a Product Type (UFP) and a Product Type (DFP) are declared in the ID Header. These products Shall return Product Type VDOs for both UFP and DFP beginning with the UFP VDO, then by a 32-bit Pad Object (defined as all '0's), followed by the DFP VDO as shown in Figure 6.17, "Discover Identity Command response for a DRD". Figure 6.17 Discover Identity Command response for a DRD 6.4.4.3.1.1 ID Header VDO The ID Header VDO contains information corresponding to the Power Delivery Product. The fields in the ID Header VDO Shall be as defined in Section Table 6.33, "ID Header VDO". Table 6.33 ID Header VDO Bit(s) Description Reference B31 USB Communications Capable as USB Host Section 6.4.4.3.1.1.1  Shall be set to one if the product is capable of enumerating USB Devices.  Shall be set to zero otherwise. B30 USB Communications Capable as a USB Device Section 6.4.4.3.1.1.2  Shall be set to one if the product is capable of being enumerated as a USB Device.  Shall be set to zero otherwise B29…27 SOP Product Type (UFP) Section 6.4.4.3.1.1.3  000b – Not a UFP  001b – PDUSB Hub  010b – PDUSB Peripheral  011b – PSD  100b…111b – Reserved, Shall Not be used. SOP’ Product Type (Cable Plug/VPD)  000b – Not a Cable Plug/VPD  001b…010b – Reserved, Shall Not be used.  011b – Passive Cable  100b – Active Cable  101b – Reserved, Shall Not be used.  110b – VCONN Powered USB Device (VPD)  111b – Reserved, Shall Not be used. Header No. of Data Objects = 4-71 VDM Header ID Header VDO Cert Stat VDO 0..32 Product Type VDO(s) Product VDO 1. Only Data objects defined in this specification can be sent as part of the Discover Identity Command. 2. The following sections define the number and content of the VDOs for each Product Type. Header No. of Data Objects = 7 VDM Header ID Header VDO Cert Stat VDO Product VDO Product Type VDO(s) yp ( ) UFP Pad DFP Page 170 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.1 USB Communications Capable as a USB Host The USB Communications Capable as USB Host field is used to indicate whether or not the Port has a USB Host Capability. 6.4.4.3.1.1.2 USB Communications Capable as a USB Device The USB Communications Capable as a USB Device field is used to indicate whether or not the Port has a USB Device Capability. 6.4.4.3.1.1.3 Product Type (UFP) The SOP Product Type (UFP) field indicates the type of Product when in UFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP Product Type (UFP) field Shall be the closest categorization of the main functionality of the Product in UFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in UFP role regardless of the present Data Role. Table 6.34, "Product Types (UFP)" defines the Product Type VDOs which Shall be returned. B26 Modal Operation Supported Section 6.4.4.3.1.1.4  Shall be set to one if the product (UFP/Cable Plug) is capable of supporting Modal Operation (Alternate Modes).  Shall be set to zero otherwise. B25…23 SOP - Product Type (DFP) Section 6.4.4.3.1.1.6  000b – Not a DFP  001b – PDUSB Hub  010b – PDUSB Host  011b – Power Brick  100b…111b – Reserved, Shall Not be used. SOP’: Reserved, Shall Not be used. B22…21 Connector Type Section 6.4.4.3.1.1.7  00b – Reserved, for compatibility with legacy systems.  01b – Reserved, Shall Not be used.  10b – USB Type-C Receptacle  11b – USB Type-C Plug B20…16 Reserved, Shall Not be used. B15…0 USB Vendor ID Section 6.4.4.3.1.1.8 [USB 2.0]/[USB 3.2]/[USB4] Table 6.34 Product Types (UFP) Product Type Description Product Type VDO Reference Undefined Shall be used when this is not a UFP. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PDUSB Peripheral Shall be used when the Product is a PDUSB Device other than a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PSD Shall be used when the Product is a PSD, e.g., power bank. None Table 6.33 ID Header VDO (Continued) Bit(s) Description Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 171 6.4.4.3.1.1.4 Product Type (Cable Plug) The SOP’ Product Type (Cable Plug/VPD) field indicates the type of Product when the Product is a Cable Plug or VPD, whether a VDO will be returned and if so the type of VDO to be returned. Table 6.35, "Product Types (Cable Plug/ VPD)" defines the Product Type VDOs which Shall be returned. 6.4.4.3.1.1.5 Modal Operation Supported The Modal Operation Supported bit is used to indicate whether or not the Product (either a Cable Plug or a device that can operate in the UFP role) is capable of supporting Modes. The Modal Operation Supported bit does not describe a DFP's Alternate Mode Controller functionality. A product that supports Modal Operation Shall respond to the Discover SVIDs Command with a list of SVIDs for all of the Modes it is capable of supporting whether or not those Modes can currently be entered. 6.4.4.3.1.1.6 Product Type (DFP) The SOP - Product Type (DFP) field indicates the type of Product when in DFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP - Product Type (DFP) field Shall be the closest categorization of the main functionality of the Product in DFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in DFP role regardless of the present Data Role. Table 6.36, "Product Types (DFP)" defines the Product Type VDOs which Shall be returned. In SOP’ Communication (Cable Plugs and VPDs) this bit field is Reserved and Shall be set to zero. 6.4.4.3.1.1.7 Connector Type Field The Connector Type field (B22…21) Shall contain a value identifying it as either a USB Type-C receptacle or a USB Type-C plug. Table 6.35 Product Types (Cable Plug/VPD) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None Active Cable Shall be used when the Product is a cable that incorporates signal conditioning circuits. Active Cable VDO Section 6.4.4.3.1.7 Passive Cable Shall be used when the Product is a cable that does not incorporate signal conditioning circuits. Passive Cable VDO Section 6.4.4.3.1.6 VCONN Powered USB Device Shall be used when the Product is a PDUSB VCONN Powered USB Device. VPD VDO Section 6.4.4.3.1.9 Table 6.36 Product Types (DFP) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. DFP VDO Section 6.4.4.3.1.7 PDUSB Host Shall be used when the Product is a PDUSB Host or a PDUSB host that supports one or more Alternate Modes as an AMC. DFP VDO Section 6.4.4.3.1.6 Charger Shall be used when the Product is a Charger. DFP VDO Section 6.4.4.3.1.9 Page 172 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.8 Vendor ID Manufacturers Shall set the USB Vendor ID field to the value of the Vendor ID assigned to them by USB-IF. For USB Devices or Hubs which support USB Communications the USB Vendor ID field Shall be identical to the Vendor ID field defined in the product's USB Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.4.4.3.1.2 Cert Stat VDO The Cert Stat VDO Shall contain the XID assigned by USB-IF to the product before certification in binary format. The fields in the Cert Stat VDO Shall be as defined in Table 6.37, "Cert Stat VDO". 6.4.4.3.1.3 Product VDO The Product VDO contains identity information relating to the product. The fields in the Product VDO Shall be as defined in Table 6.38, "Product VDO". Manufacturers Should set the USB Product ID field to a unique value identifying the product and Should set the bcdDevice field to a version number relevant to the release version of the product. 6.4.4.3.1.4 UFP VDO The UFP VDO defined in this section Shall be returned by Ports capable of operating as a UFP including traditional USB peripherals, USB Hub's upstream Port and DRD capable host Ports. The UFP VDO defined in this section Shall be sent when the Product Type (UFP) field in the ID Header VDO is given as a PDUSB Peripheral or PDUSB Hub. Table 6.39, "UFP VDO" defines the UFP VDO that Shall be sent based on the Product Type. A [USB4] UFP Shall support the Structured VDM Discover Identity Command. Table 6.37 Cert Stat VDO Bit(s) Description Reference B31...0 32-bit unsigned integer, XID Assigned by USB-IF Table 6.38 Product VDO Bit(s) Description Reference B31...16 16-bit unsigned integer, USB Product ID [USB 2.0]/[USB 3.2] B15...0 16-bit unsigned integer, bcdDevice [USB 2.0]/[USB 3.2] Table 6.39 UFP VDO Bit(s) Description Reference B31…29 UFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.3 = 011b Values 100b…111b are Reserved, Shall Not be used. B28 Reserved Shall be set to zero. B27…24 Device Capability Bit Description 0 [USB 2.0] Device Capable 1 [USB 2.0] Device Capable (Billboard only) 2 [USB 3.2] Device Capable 3 [USB4] Device Capable B23…22 Connector Type (Legacy) Deprecated, Shall be set to 00b. B21…11 Reserved Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 173 6.4.4.3.1.4.1 VDO Version Field The UFP VDO Version field contains a VDO Version for this VDM Version number. This field indicates the expected content for the UFP VDOs. 6.4.4.3.1.4.2 Device Capability Field The Device Capability bit-field describes the UFP's Capabilities when operating as either a PDUSB Device or PDUSB Hub. B10…8 VCONN Power When the VCONN Required field is set to “Yes” the VCONN Power Field indicates the VCONN power needed by the AMA for full functionality:  000b = 1W  001b = 1.5W  010b = 2W  011b = 3W  100b = 4W  101b = 5W  110b = 6W 111b = Reserved, Shall Not be used. When the VCONN Required field is set to “No” the VCONN Power field is Reserved and Shall be set to zero. B7 VCONN Required Indicates whether the AMA requires VCONN in order to function.  0 = No  1 = Yes When the Alternate Modes field indicates no modes are supported, the VCONN Required field is Reserved and Shall be set to zero. B6 VBUS Required Indicates whether the AMA requires VBUS in order to function.  0 = Yes  1 = No When the Alternate Modes field indicates no modes are supported, the VBUS Required field is Reserved and Shall be set to zero. B5…3 Alternate Modes Bit Description 0 Supports [TBT3] Alternate Mode 1 Supports Alternate Modes that reconfigure the signals on the [USB Type-C 2.4] connector – except for [TBT3]. 2 Supports Alternate Modes that do not reconfigure the signals on the [USB Type-C 2.4] connector. B2…0 USB Highest Speed  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b =[USB4] Gen4  101b…111b = Reserved and Shall be set to zero. Table 6.39 UFP VDO (Continued) Bit(s) Description Reference Page 174 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The bits in the bit-field Shall be non-zero when the corresponding USB Device speed is supported and Shall be set to zero when the corresponding USB Device speed is not supported. [USB 2.0] "Device capable" and "Device capable Billboard only" (bits 0 and 1) Shall Not be simultaneously set. 6.4.4.3.1.4.3 Connector Type Field Th Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.4.4 VCONN Power Field When the VCONN Required field indicates that VCONN is required the VCONN Power field Shall indicate how much power an AMA needs in order to fully operate. When the VCONN Required field is set to "No" the VCONN Power field is Reserved and Shall be set to zero. 6.4.4.3.1.4.5 VCONN Required Field The VCONN Required field Shall indicate whether VCONN is needed for the AMA to operate. The VCONN Required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.6 VBUS Required Field The VBUS Required field Shall indicate whether VBUS is needed for the AMA to operate. The VBUS required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.7 Alternate Modes Field The Alternate Modes field Shall be used to identify all the types of Alternate Modes, if any, a device supports. 6.4.4.3.1.4.8 USB Highest Speed Field The USB Highest Speed field Shall indicate the Port's highest speed capability. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 175 6.4.4.3.1.5 DFP VDO The DFP VDO Shall be returned by Ports capable of operating as a DFP; including those implemented by Hosts, Hubs and Power Bricks. The DFP VDO Shall be returned when the Product Type (DFP) field in the ID Header VDO is given as Power Brick, PDUSB Host or PDUSB Hub. Table 6.40, "DFP VDO" defines the DFP VDO that Shall be sent. 6.4.4.3.1.5.1 VDO Version Field The DFP VDO Version field Shall contain a VDO Version for this VDM Version number. This field indicates the expected content for the DFP VDO. 6.4.4.3.1.5.2 Host Capability Field The Host Capability bit-field Shall describe whether the DFP can operate as a PDUSB Host and the DFP's Capabilities when operating as a PDUSB Host. Power Bricks and PDUSB Hubs Shall set the Host Capability bits to zero. 6.4.4.3.1.5.3 Connector Type Field The Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.5.4 Port Number Field The Port Number field Shall be a Static unique number that unambiguously identifies each [USB Type-C 2.4] DFP, including DRPs, on the device. Note: This number is independent of the USB Port number. Table 6.40 DFP VDO Bit(s) Field Description B31…29 DFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.2 = 010b Values 011b…111b are Reserved and Shall Not be used B28…27 Reserved Shall be set to zero. B26…24 Host Capability Bit Description 0 [USB 2.0] Host Capable 1 [USB 3.2] Host Capable 2 [USB4] Host Capable B23…22 Connector Type (Legacy) Shall be set to 00b. B21…5 Reserved Shall be set to zero. B4…0 Port Number Unique Port number to identify a specific Port on a multi-Port device. Page 176 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.6 Passive Cable VDO The Passive Cable VDO defined in this section Shall be sent when the Product Type is given as Passive Cable. Table 6.41, "Passive Cable VDO" defines the Cable VDO which Shall be sent. A Passive Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. A Passive Cable Shall Not incorporate data bus signal conditioning circuits and hence has no concept of Super Speed Directionality. A Passive Cable Shall include a VBUS wire and Shall only respond to SOP’ Communication. Passive Cables Shall support the Structured VDM Discover Identity Command and Shall return the Passive Cable VDO in a Discover Identity Command ACK as shown in Table 6.41, "Passive Cable VDO". Table 6.41 Passive Cable VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive (Passive Cable)  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Passive Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency (Passive Cable)  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b – > 70ns (>~7m) Note: 1001b ….1111b Reserved and Shall Not be used B12…11 Cable Termination Type (Passive Cable)  00b = VCONN not required. Cable Plugs that only support Discover Identity Commands Shall set these bits to 00b.  01b = VCONN required  10b…11b = Reserved and Shall Not be used B10…9 Maximum VBUS Voltage (Passive Cable) Maximum Cable VBUS Voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 177 6.4.4.3.1.6.1 HW Version Field The HW Version (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.6.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.6.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.6.4 USB Type-C plug to USB Type-C/Captive Field The USB Type-C plug to USB Type-C/Captive (Passive Cable) field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.6.5 EPR Mode Capable The EPR Capable (Passive Cable) bit is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.6.6 Cable Latency Field The Cable Latency (Passive Cable) field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. 6.4.4.3.1.6.7 Cable Termination Type Field The Cable Termination Type (Passive Cable) field (B12…11) Shall contain a value indicating whether the Passive Cable needs VCONN only initially in order to support the Discover Identity Command, after which it can be removed, or the Passive Cable needs VCONN to be continuously applied in order to power some feature of the Cable Plug. 6.4.4.3.1.6.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Passive Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated using a Fixed Supply over the cable as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage (Passive Cable) field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Passive B6…5 VBUS Current Handling Capability (Passive Cable)  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4…3 Reserved Shall be set to zero. B2…0 USB Highest Speed (Passive Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.41 Passive Cable VDO (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 178 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Passive Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.6.9 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Passive Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. 6.4.4.3.1.6.10 USB Highest Speed Field The USB Highest Speed (Passive Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 179 6.4.4.3.1.7 Active Cable VDOs An Active Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. An Active Cable Shall incorporate data bus signal conditioning circuits and May have a concept of Super Speed Directionality on its Super Speed wires. An Active Cable May include a VBUS wire. An Active Cable:  Shall respond to SOP’ Communication.  May respond to SOP’’ Communication.  Shall support the Structured VDM Discover Identity Command.  In the Discover Identity Command ACK:  Shall set the Product Type in the ID Header VDO to Active Cable.  Shall return the Active Cable VDOs defined in Table 6.42, "Active Cable VDO1" and Table 6.43, "Active Cable VDO2".. Table 6.42 Active Cable VDO1 Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Active Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b –1000ns (~100m)  1001b –2000ns (~200m)  1010b – 3000ns (~300m)  1001b ….1111b Reserved and Shall Not be used Note: Includes latency of electronics in Active Cable. B12…11 Cable Termination Type (Active Cable)  00b…01b = Reserved and Shall Not be used  10b = One end Active, one end passive, VCONN required  11b = Both ends Active, VCONN required 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 180 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 B10…9 Maximum VBUS Voltage (Active Cable) Maximum Cable VBUS voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. B8 SBU Supported  0 = SBU connections supported  1 = SBU connections are not supported B7 SBU Type When SBU Supported = 1 this bit Shall be Ignored When SBU Supported = 0:  0 = SBU is passive  1 = SBU is active B6…5 VBUS Current Handling Capability (Active Cable) When VBUS Through Cable is “No”, this field Shall be Ignored. When VBUS Through Cable is “Yes”:  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4 VBUS Through Cable  0 = No  1 = Yes B3 SOP’’ Controller Present  0 = No SOP’’ controller present  1 = SOP’’ controller present B2…0 USB Highest Speed (Active Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.43 Active Cable VDO2 Bit(s) Field Description B31…24 Maximum Operating Temperature The maximum internal operating temperature in °C. It might or might not reflect the plug’s skin temperature. B23…16 Shutdown Temperature The temperature, in °C, at which the cable will go into thermal shutdown so as not to exceed the allowable plug skin temperature. B15 Reserved Shall be set to zero. B14…12 U3/CLd Power  000b: >10mW  001b: 5-10mW  010b: 1-5mW  011b: 0.5-1mW  100b: 0.2-0.5mW  101b: 50-200µW  110b: <50µW  111b: Reserved and Shall Not be used Table 6.42 Active Cable VDO1 (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 181 6.4.4.3.1.7.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.7.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.7.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for the Active Cable VDOs. 6.4.4.3.1.7.4 Connector Type Field The USB Type-C plug to USB Type-C/Captive field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.7.5 EPR Mode Capable The EPR Capable (Active Cable) is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.7.6 Cable Latency Field The Cable Latency field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. B11 U3 to U0 transition mode  0b: U3 to U0 direct  1b: U3 to U0 through U3S B10 Physical connection  0b = Copper  1b = Optical B9 Active element  0b = Active Re-driver  1b = Active Re-timer B8 USB4 Supported  0b = [USB4] supported  1b = [USB4]not supported B7…6 USB 2.0 Hub Hops Consumed Number of [USB 2.0] ‘hub hops’ cable consumes. Shall be set to zero if USB 2.0 not supported. B5 USB 2.0 Supported  0b = [USB 2.0] supported  1b = [USB 2.0] not supported B4 USB 3.2 Supported  0b = [USB 3.2] SuperSpeed supported  1b = [USB 3.2] SuperSpeed not supported B3 USB Lanes Supported  0b = One lane  1b = Two lanes B2 Optically Isolated Active Cable  0b = No  1b = Yes B1 USB4 Asymmetric Mode Supported  0b = No  1b = Yes Shall be set to zero if asymmetry is not supported. B0 USB Gen  0b = Gen 1  1b = Gen 2 or higher Note: See VDO1 USB Highest Speed for details of Gen supported. Table 6.43 Active Cable VDO2 (Continued) Bit(s) Field Description Page 182 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.7.7 Cable Termination Type Field The Cable Termination Type (Active Cable) field (B12…11) Shall contain a value corresponding to whether the Active Cable has one or two Cable Plugs requiring power from VCONN. 6.4.4.3.1.7.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Active Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. When this field is set to 20V, the cable will safely carry a Programmable Power Supply APDO of 20V where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Active Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Active Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.7.9 SBU Supported Field The SBU Supported field (B8) Shall indicate whether the cable supports the SBUs in the cable. 6.4.4.3.1.7.10 SBU Type Field The SBU Type field (B7) Shall indicate whether the SBUs are passive or active (e.g., digital). 6.4.4.3.1.7.11 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Active Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. The VBUS Current Handling Capability (Active Cable) field Shall only be Valid when the VBUS Current Handling Capability (Active Cable) field indicates an end-to-end VBUS wire. 6.4.4.3.1.7.12 VBUS Through Cable Field The VBUS Through Cable field (B4) Shall indicate whether the cable contains an end-to-end VBUS wire. 6.4.4.3.1.7.13 SOP'' Controller Present Field The SOP’’ Controller Present field (B3) Shall indicate whether one of the Cable Plugs is capable of SOP’’ Communication in addition to the Normative SOP’ Communication. 6.4.4.3.1.7.14 USB Highest Speed Field The USB Highest Speed (Active Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. 6.4.4.3.1.7.15 Maximum Operating Temperature Field Maximum Operating Temperature field (B31…24) Shall report the maximum allowable operating temperature inside the plug in °C. 6.4.4.3.1.7.16 Shutdown Temperature Field Shutdown Temperature field (B23…16) Shall indicate the temperature inside the plug, in °C, at which the plug will shut down its active signaling components. When this temperature is reached, it will be reported in the Active Cable Status Message through the Thermal Shutdown bit. 6.4.4.3.1.7.17 U3/CLd Power Field The U3/CLd Power field (B14…12) Shall indicate the power the cable consumes while in [USB 3.2] U3 or [USB4] CLd. 6.4.4.3.1.7.18 U3 to U0 Transition Mode Field The U3 to U0 transition mode field (B11) Shall indicate which U3 to U0 mode the cable supports. This does not include the power in U3S if supported. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 183 6.4.4.3.1.7.19 Physical Connection Field The Physical connection field (B10) Shall indicate the cable's construction, whether the connection between the active elements is copper or optical. 6.4.4.3.1.7.20 Active element Field The Active element field (B9) Shall indicate the cable's active element, whether the active element is a re-timer or a re-driver. 6.4.4.3.1.7.21 USB4 Supported Field The USB4 Supported field (B8) Shall indicate whether or not the cable supports [USB4] operation. 6.4.4.3.1.7.22 USB 2.0 Hub Hops Consumed field The USB 2.0 Hub Hops Consumed field (B7…6) Shall indicate the number of USB 2.0 'hub hops' that are lost due to the transmission time of the cable. 6.4.4.3.1.7.23 USB 2.0 Supported Field The USB 2.0 Supported field (B5) Shall indicate whether or not the cable supports [USB 2.0] only signaling. 6.4.4.3.1.7.24 USB 3.2 Supported Field The USB 3.2 Supported field (B4) Shall, indicate whether or not the cable supports [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.25 USB Lanes Supported Field The USB Lanes Supported field (B3) Shall indicate whether the cable supports one or two lanes of [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.26 Optically Isolated Active Cable Field The Optically Isolated Active Cable field (B2) Shall indicate whether this cable is an optically isolated Active Cable or not (as defined in [USB Type-C 2.4]). Optically Isolated Active Cables Shall have a re-timer or linear re-driver (LRD) as the active element and do not support [USB 2.0] or carry VBUS. 6.4.4.3.1.7.27 USB4 Asymmetric Mode Supported Field The USB4 Asymmetric Mode Supported field (B1) Shall indicate that the Active Cable supports asymmetric mode as defined in [USB4] and [USB Type-C 2.4]. 6.4.4.3.1.7.28 USB Gen Field The USB Gen field (B0) Shall indicate the signaling Gen the cable supports. Gen 1 Shall only be used by [USB 3.2] cables as indicated by the USB 3.2 Supported field. Gen 2 or higher May be used by either [USB 3.2] or [USB4] cables as indicated by their respective supported fields. When Gen 2 or higher is indicated the USB Highest Speed (Active Cable) field in VDO1 Shall indicate the actual Gen supported. 6.4.4.3.1.8 Alternate Mode Adapter VDO The Alternate Mode Adapter (AMA) VDO has been Deprecated. PDUSB Devices which support one or more Alternate Modes Shall set an appropriate Product Type (UFP), and Shall set the Modal Operation Supported bit to '1'. Page 184 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.9 VCONN Powered USB Device VDO The VCONN Powered USB Device (VPD) VDO defined in this section Shall be sent when the Product Type is given as VCONN Powered USB Device. Table 6.44, "VPD VDO" defines the VPD VDO which Shall be sent. 6.4.4.3.1.9.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.9.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.9.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.9.4 Maximum VBUS Voltage Field The Maximum VBUS Voltage field (B16…15) Shall contain the maximum voltage that a Sink Shall Negotiate through the VPD Charge Through Port as part of an Explicit Contract. Note: The maximum voltage that will be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Table 6.44 VPD VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b  Values 001b…111b are Reserved and Shall Not be used. B20...17 Reserved Shall be set to zero. B16…15 Maximum VBUS Voltage Maximum VPD VBUS Voltage:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V1 (Deprecated) B14 Charge Through Current Support Charge Through Current Support bit=1b:  0b - 3A capable.  1b - 5A capable Charge Through Current Support bit = 0b:  Reserved and Shall be set to zero. B13 Reserved Shall be set to zero. B12…7 VBUS Impedance Charge Through Current Support bit = 1b: VBUS impedance through the VPD in 2 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Reserved and Shall be set to zero. B6…1 Ground Impedance Charge Through Current Support bit = 1b: Ground impedance through the VPD in 1 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Shall be set to zero. B0 Charge Through Support  1b – the VPD supports Charge Through  0b – the VPD does not support Charge Through 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 185 Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Maximum VBUS Voltage field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.9.5 VBUS Impedance Field The VBUS Impedance field (B12…7) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the VBUS IR Drop limit of 0.5V between the Source and itself. If the Sink can tolerate a larger IR Drop on VBUS it May do so. 6.4.4.3.1.9.6 Ground Impedance Field The Ground Impedance field (B6…1) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the Ground IR Drop limit of 0.25V between the Source and itself. 6.4.4.3.1.9.7 Charge Through Field The Firmware Version field (B0) Shall be set to 1b when the VPD supports Charge Through and 0b otherwise. Page 186 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.2 Discover SVIDs The Discover SVIDs Command is used by an Initiator to determine the SVIDs for which a Responder has Modes. The Discover SVIDs Command is used in conjunction with the Discover Modes Command in the Discovery Process to determine which Modes a device supports. The list of SVIDs is always terminated with one or two 0x0000 SVIDs. The SVID in the Discover SVIDs Command Shall be set to the PD SID (see "Table 6.31, "SVID Values") by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover SVIDs Command request Shall be set to 1 since the Discover SVIDs Command request Shall Not contain any VDOs. The Discover SVIDs Command ACK sent back by the Responder Shall contain one or more SVIDs. The SVIDs are returned 2 per VDO (see Table 6.45, "Discover SVIDs Responder VDO"). If there are an odd number of supported SVIDs, the Discover SVIDs Command is returned ending with a SVID value of 0x0000 in the last part of the last VDO. If there are an even number of supported SVIDs, the Discover SVIDs Command is returned ending with an additional VDO containing two SVIDs with values of 0x0000. A Responder Shall only return SVIDs for which a Discover Modes Command request for that SVID will return at least one Alternate Mode. A Responder that does not support any SVIDs Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover SVIDs Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the Responder supports 12 or more SVIDs then the Discover SVIDs Command Shall be executed multiple times until a Discover SVIDs VDO is returned ending either with a SVID value of 0x0000 in the last part of the last VDO or with a VDO containing two SVIDs with values of 0x0000. Each Discover SVID ACK Message, other than the one containing the terminating 0x0000 SVID, Shall convey 12 SVIDs. The Responder Shall restart the list of SVIDs each time a Discover Identity Command request is received from the Initiator. Note: Since a Cable Plug does not retry Messages if the GoodCRC Message from the Initiator becomes corrupted the Cable Plug will consider the Discover SVIDs Command ACK unsent and will send the same list of SVIDs again. Figure 6.18, "Example Discover SVIDs response with 3 SVIDs" shows an example response to the Discover SVIDs Command request with two VDOs containing three SVIDs. Figure 6.19, "Example Discover SVIDs response with 4 SVIDs" shows an example response with two VDOs containing four SVIDs followed by an empty VDO to terminate the response. Figure 6.20, "Example Discover SVIDs response with 12 SVIDs followed by an empty response" shows an example response with six VDOs containing twelve SVIDs followed by an additional request that returns an empty VDO indicating there are no more SVIDs to return. Figure 6.18 Example Discover SVIDs response with 3 SVIDs Table 6.45 Discover SVIDs Responder VDO Bit(s) Field Description B31…16 SVID n 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an even number of SVIDs. B15…0 SVID n+1 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an odd or even number of SVIDs. Header No. of Data Objects = 3 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) 0x0000 (B15..0) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 187 Figure 6.19 Example Discover SVIDs response with 4 SVIDs Figure 6.20 Example Discover SVIDs response with 12 SVIDs followed by an empty response Header No. of Data Objects = 4 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 0x0000 (B31..16) 0x0000 (B15..0) Header No. of Data Objects = 7 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 SVID 4 (B31..16) SVID 5 (B15..0) VDO 4 SVID 6 (B31..16) SVID 7 (B15..0) VDO 5 SVID 8 (B31..16) SVID 9 (B15..0) Header No. of Data Objects = 2 VDM Header VDO 1 0x0000 (B31..16) 0x0000 (B15..0) VDO 6 SVID 10 (B31..16) SVID 11 (B15..0) Page 188 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.3 Discover Modes The Discover Modes Command is used by an Initiator to determine the Modes a Responder supports for a given SVID. The SVID in the Discover Modes Command Shall be set to the SVID for which Modes are being requested by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover Modes Command request Shall be set to 1 since the Discover Modes Command request Shall Not contain any VDOs. The Discover Modes Command ACK sent back by the Responder Shall contain one or more Modes. The Discover Modes Command ACK Shall contain a Message Header with the Number of Data Objects field set to a value of 2 to 7 (the actual value is the number of Alternate Mode objects plus one). If the ID is a VID, the structure and content of the VDO is left to the Vendor. If the ID is a SID, the structure and content of the VDO is defined by the relevant standard’s body. A Responder that does not support any Modes Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover Modes Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes" shows an example of a Discover Modes Command response from a Responder which supports three Modes for a given SVID. Figure 6.21 Example Discover Modes response for a given SVID with 3 Modes 6.4.4.3.4 Enter Mode Command The Enter Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to enter a specified Alternate Mode of operation. Only a DFP Shall initiate the Enter Mode Process which it starts after it has successfully completed the Discovery Process. The value in the Object Position field in the VDM Header Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes"). The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. The Number of Data Objects field in the Message Header in the Command request Shall be set to either 1 or 2 since the Enter Mode Command request Shall Not contain more than 1 VDO. When a VDO is included in an Enter Mode Command request the contents of the 32-bit VDO is defined by the Alternate Mode. The Number of Data Objects field in the Command response Shall be set to 1 since an Enter Mode Command response (ACK, NAK) Shall Not contain any VDOs. Before entering a Alternate Mode, by sending the Enter Mode Command request that requires the reconfiguring of any pins on entry to that Alternate Mode, the Initiator Shall ensure that those pins being reconfigured are placed into the USB Safe State. Before entering an Alternate Mode that requires the reconfiguring of any pins, the Responder Shall ensure that those pins being reconfigured are placed into either USB operation or the USB Safe State. A device May support multiple Modes with one or more active at any point in time. Any interactions between them are the responsibility of the Standard or Vendor. Where there are multiple Active Modes at the same time Modal Operation Shall start on entry to the first Alternate Mode. Header No. of Data Objects = 4 VDM Header Mode 1 Mode 2 Mode 3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 189 On receiving an Enter Mode Command requests the Responder Shall respond with either an ACK or a NAK response. The Responder is not allowed to return a BUSY response. The value in the Object Position field of the Enter Mode Command response Shall contain the same value as the received Enter Mode Command request. If the Responder responds to the Enter Mode Command request with an ACK, the Responder Shall enter the Alternate Mode before sending the ACK. The Initiator Shall enter the Alternate Mode on reception of the ACK. Successful transmission of the Message confirms to the Responder that the Initiator will enter an Active Mode. See Figure 8.111, "DFP to UFP Enter Mode" for more details. If the Responder responds to the Enter Mode Command request with a NAK, the Alternate Mode is not entered. If not presently in Modal Operation the Initiator Shall return to USB operation. If not presently in Modal Operation the Responder Shall remain in either USB operation or the USB Safe State. If the Initiator fails to receive a response within tVDMWaitModeEntry it Shall Not enter the Alternate Mode but return to USB operation. Figure 6.22, "Successful Enter Mode sequence" shows the sequence of events during the transition between USB operation and entering an Alternate Mode. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.23, "Unsuccessful Enter Mode sequence due to NAK" illustrates that when the Responder returns a NAK the transition to an Alternate Mode do not take place and the Responder and Initiator remain in their default USB roles. Figure 6.22 Successful Enter Mode sequence DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC ACK USB Safe State USB USB or USB Safe State New Mode New Mode Page 190 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.23 Unsuccessful Enter Mode sequence due to NAK Once the Alternate Mode is entered, the device Shall remain in that Active Mode until the Exit Mode Command is successful (see Section 6.4.4.3.5, "Exit Mode Command"). The following events Shall also cause the Port Partners and Cable Plug(s) to exit all Active Modes:  A PD Hard Reset.  Error Recovery.  The Port Partners or Cable Plug(s) are Detached.  A Cable Reset (only exits the Cable Plug's Active Modes).  A Data Reset (removing power briefly resets all the Active Modes in the Cable Plug). The Initiator Shall return to USB Operation within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. The Responder Shall return to either USB operation or USB Safe State within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. A DR_Swap Message Shall Not be sent during Modal Operation between the Port Partners (see Section 6.3.9, "DR_Swap Message"). 6.4.4.3.5 Exit Mode Command The Exit Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to exit its Active Mode and return to normal USB operation. Only the DFP Shall initiate the Exit Mode Process. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC NAK USB Safe State USB USB or USB Safe State USB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 191 Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 111b in the Object Position field Shall indicate that all Active Modes Shall be exited. The Number of Data Objects field in both the Command request and Command response (ACK, NAK) Shall be set to 1 since an Exit Mode Command Shall Not contain any VDOs. The Responder Shall exit its Active Mode before sending the response Message. The Initiator Shall exit its Active Mode when it receives the ACK. The Responder Shall Not return a BUSY acknowledgment and Shall only return a NAK acknowledgment to a request not containing an Active Mode (i.e., Invalid object position). An Initiator which fails to receive an ACK within tVDMWaitModeExit or receives a NAK or BUSY response Shall exit its Active Mode. See Figure 8.112, "DFP to UFP Exit Mode" for more details. Figure 6.24, "Exit Mode sequence" shows the sequence of events during the transition between exiting an Active Mode and USB operation. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.24 Exit Mode sequence 6.4.4.3.6 Attention The Attention Command May be used by the Initiator to notify the Responder that it requires service. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 000b or 111b in the Object Position field Shall Not be used by the Attention Command. DFP (Initiator) UFP (Responder) Exit Mode GoodCRC GoodCRC ACK USB Safe State USB or USB Safe State Mode Mode USB Page 192 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Number of Data Objects field in the Message Header Shall be set to 1 or 2 since the Attention Command Shall Not contain more than 1 VDO. When a VDO is included in an Attention Command the contents of the 32-bit VDO is defined by the Alternate Mode. Figure 6.24, "Exit Mode sequence" shows the sequence of events when an Attention Command is received. Figure 6.25 Attention Command request/response sequence 6.4.4.4 Command Processes The Message flow of Commands during a Process is a query followed by a response. Every Command request sent has to be responded to with a GoodCRC Message. The GoodCRC Message only indicates the Command request was received correctly; it does not mean that the Responder understood or even supports a particular SVID. Figure 6.26, "Command request/response sequence" shows the request/response sequence including the GoodCRC Messages. Initiator Responder GoodCRC Command (Attention) Command Complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 193 Figure 6.26 Command request/response sequence In order for the Initiator to know that the Command request was actually consumed, it needs an acknowledgment from the Responder. There are three responses that indicate the Responder received and processed the Command request:  ACK  NAK  BUSY The Responder Shall complete:  Enter Mode requests within tVDMEnterMode.  Exit Mode requests within tVDMExitMode.  Other requests within tVDMReceiverResponse. An Initiator not receiving a response within the following times Shall timeout and return to either the PE_SRC_Ready or PE_SNK_Ready state (as appropriate):  Enter Mode requests within tVDMWaitModeEntry.  Exit Mode requests within tVDMWaitModeExit.  Other requests within tVDMSenderResponse. The Responder Shall respond with:  ACK if it recognizes the SVID and can process it at this time.  NAK:  if it recognizes the SVID but cannot process the Command request Initiator Responder Command (request) GoodCRC GoodCRC Command (response) Command Complete Page 194 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  or if it does not recognize the SVID  or if it does not support the Command  or if a VDO contains a field which is Invalid.  BUSY if it recognizes the SVID and the Command but cannot process the Command request at this time. The ACK, NAK or BUSY response Shall contain the same SVID as the Command request. 6.4.4.4.1 Discovery Process The Initiator (usually the DFP) always begins the Discovery Process. The Discovery Process has two phases. In the first phase, the Discover SVIDs Command request is sent by the Initiator to get the list of SVIDs the Responder supports. In the second phase, the Initiator sends a Discover Modes Command request for each SVID supported by both the Initiator and Responder. 6.4.4.4.2 Enter Vendor Mode / Exit Vendor Mode Processes The result of the Discovery Process is that both the Initiator and Responder identify the Modes they mutually support. The Initiator (DFP), upon finding a suitable Alternate Mode, uses the Enter Mode Command to enable the Alternate Mode. The Responder (UFP or Cable Plug) and Initiator continue using the Active Mode until the Active Mode is exited. In a managed termination, using the Exit Mode Command, the Active Mode Shall be exited in a controlled manner as described in Section 6.4.4.3.5, "Exit Mode Command". In an unmanaged termination, triggered by:  A Power Delivery Hard Reset (i.e. Hard Reset Signaling sent by either Port Partner) or  By cable Detach (device unplugged) or  By Error Recovery the Active Mode Shall still be exited but there Shall Not be a transition through the USB Safe State. In both the managed and unmanaged terminations, the Initiator and Responder return to USB operation as defined in [USB Type-C 2.4] following an exit from an Alternate Mode. The overall Message flow is illustrated in Figure 6.27, "Enter/Exit Mode Process". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 195 Figure 6.27 Enter/Exit Mode Process 6.4.4.5 VDM Message Timing and Normal PD Messages The timing and interspersing of VDMs between regular PD Messages Shall be done without perturbing the PD AMSs. This requirement Shall apply to both Unstructured VDMs and Structured VDMs. Initiator (DFP) Responder (UFP or Cable Plug) Discover SVIDs List of SVIDs For every DFP supported SVID Modes Supported? N Stay in USB mode Y Enter Mode ACK (Responder switched to Mode) Initiator and Responder operate using Mode Return to USB mode Establish PD Contract Exit Mode or PD Hard Reset or cable unplugged or power removed? Y N USB USB or USB Safe State USB Safe State USB Alternate Mode USB or USB Safe State Alternate Mode USB Discover Modes (SVID) Modes for SVID Page 196 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The use of Structured VDMs by an Initiator Shall Not interfere with the normal PD Message timing requirements nor Shall either the Initiator or Responder interrupt a PD AMS (e.g., Negotiation, Power Role Swap, Data Role Swap etc.). The use of Unstructured VDMs Shall Not interfere with normal PD Message timing. 6.4.5 Battery_Status Message The Battery_Status Message Shall be sent in response to a Get_Battery_Status Message. The Battery_Status Message contains one Battery Status Data Object (BSDO) for one of the Batteries it supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BSDO Shall correspond to the Battery requested in the Battery Status Ref field contained in the Get_Battery_Status Message. The Battery_Status Message returns a BSDO whose format Shall be as shown in Figure 6.28, "Battery_Status Message" and Table 6.46, "Battery Status Data Object (BSDO)". The Number of Data Objects field in the Battery_Status Message Shall be set to 1. Figure 6.28 Battery_Status Message 6.4.5.1 Battery Present Capacity The Battery Present Capacity field Shall return either the Battery's State of Charge (SoC) in tenths of WH or indicate that the Battery's present State of Charge (SOC) is unknown. Table 6.46 Battery Status Data Object (BSDO) Bit(s) Field Description B31…16 Battery Present Capacity Battery’s State of Charge (SoC) in 0.1 WH increments Note: 0xFFFF = Battery’s SOC unknown B15…8 Battery Info Bit Description 0 Invalid Battery Reference Invalid Battery reference 1 Battery Present Battery is present when set 3…2 Battery Charging Status When Battery Present is ‘1’ Shall contain the Battery charging status:  00b: Battery is Charging.  01b: Battery is Discharging.  10b: Battery is Idle.  11b: Reserved, Shall Not be used. When Battery Present is ‘0’:  11b…00b: Reserved, Shall Not be used. 7…4 Reserved, Shall Not be used. B7…0 Reserved Shall be set to zero Header No. of Data Objects = 1 BSDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 197 6.4.5.2 Battery Info The Battery Info field Shall be used to report additional information about the Battery's present status. The Battery Info field's bits Shall reflect the present conditions under which the Battery is operating in the systems. 6.4.5.2.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Status Message contains a reference to a Battery or Battery Slot (see Section 6.5.1.13, "Number of Batteries/Battery Slots Field") that does not exist. 6.4.5.2.2 Battery Present The Battery Present bit Shall be set whenever the Battery is present. It Shall always be set for Batteries that are not Hot Swappable Batteries. For Hot Swappable Batteries, the Battery Present bit Shall indicate whether the Battery is Attached or Detached. 6.4.5.2.3 Battery Charging Status The Battery Charging Status bits indicate whether the Battery is being charged, discharged or is idle (neither charging nor discharging). These bits Shall be set when the Battery Present bit is set. Otherwise, when the Battery Present bit is zero the Battery Charging Status bits Shall also be zero. Page 198 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6 Alert Message The Alert Message is provided to allow Port Partners to inform each other when there is a status change event. Some of the events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Alert Message Shall only be sent when the Source or Sink detects a status change. The Alert Message Shall contain exactly one Alert Data Object (ADO) and the format Shall be as shown in Figure 6.29, "Alert Message" and Table 6.47, "Alert Data Object (ADO)". Figure 6.29 Alert Message Table 6.47 Alert Data Object (ADO) Bit(s) Field Description B31…24 Type of Alert Bit Description 0 Reserved and Shall be set to zero. 1 Battery Status Change Event Battery Status Change Event (Attach/Detach/charging/discharging/ idle) 2 OCP Event OCP event when set (Source only, for Sink Reserved and Shall be set to zero). 3 OTP Event OTP event when set 4 Operating Condition Change Operating Condition Change when set 5 Source Input Change Event Source Input Change Event when set 6 OVP Event OVP event when set 7 Extended Alert Event Extended Alert Event when set B23…20 Fixed Batteries When Battery Status Change Event bit set indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. B19…16 Hot Swappable Batteries When Battery Status Change Event bit set indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 4 and B19 corresponds to Battery 7. Header No. of Data Objects = 1 ADO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 199 6.4.6.1 Type of Alert The Type of Alert field Shall be used to report Source or Sink status changes. Only one Alert Message Shall be generated for each Event or Change; however multiple Type of Alert bits May be set in one Alert Message. Once the Alert Message has been sent the Type of Alert field Shall be cleared. A Get_Battery_Status Message Should be sent in response to a Battery status change in an Alert Message to get the details of the change. A Get_Status Message Should be sent in response to a non-Battery status change in an Alert Message from to get the details of the change. 6.4.6.1.1 Battery Status Change The Battery Status Change Event bit Shall be set when any Battery's power state changes between charging, discharging, neither. For Hot Swappable Batteries, it Shall also be set when a Battery is Attached or Detached. 6.4.6.1.2 Over-Current Protection Event The OCP Event bit Shall be set when a Source detects its output current exceeds its limits triggering its protection circuitry. This bit is Reserved for a Sink. 6.4.6.1.3 Over-Temperature Protection Event The OTP Event bit Shall be set when a Source or Sink shuts down due to over-temperature triggering its protection circuitry. 6.4.6.1.4 Operating Condition Change The Operating Condition Change bit Shall be set when a Source or Sink detects its Operating Condition enters or exits either the 'warning' or 'over temperature' temperature states. The Operating Condition Change bit Shall be set when the Source operating in the Programmable Power Supply mode detects it has changed its operating condition between Constant Voltage (CV) and Current Limit (CL). 6.4.6.1.5 Source Input Change Event The Source Input Change Event bit Shall be set when the Source/Sink's input changes. For example, when the AC input is removed, and the Source/Sink continues to be powered from one or more of its batteries or when AC returns and the Source/Sink transitions from Battery to AC operation or when the Source/Sink changes operation from one (or more) Battery to another (or more) Battery. B15…4 Reserved Shall be set to zero B3…0 Extended Alert Event Type When the Extended Alert Event bit in the Type of Alert field equals ‘1’, then the Extended Alert Event Type field indicates the event which has occurred:  0 = Reserved.  1 = Power state change (DFP only)  2 = Power button press (UFP only)  3 = Power button release (UFP only)  4 = Controller initiated wake e.g., Wake on LAN (UFP only)  5-15 = Reserved When the Extended Alert Event bit in the Type of Alert field equals ‘0’, then the Extended Alert Event Type field is Reserved and Shall be set to zero. Table 6.47 Alert Data Object (ADO) (Continued) Bit(s) Field Description Page 200 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6.1.6 Over-Voltage Protection Event The OVP Event bit Shall be set when the Sink detects its output voltage exceeds its limits triggering its protection circuitry. The OVP Event bit May be set when the Source detects its output voltage exceeds its limits triggering its protection circuitry. 6.4.6.1.7 Extended Alert Event The Extended Alert Event bit Shall be set when the event is defined as an Extended Alert Type. 6.4.6.2 Fixed Batteries The Fixed Batteries field indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. Once the Alert Message has been sent the Fixed Batteries field Shall be cleared. 6.4.6.3 Hot Swappable Batteries The Hot Swappable Batteries field indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 0 and B19 corresponds to Battery 3. Once the Alert Message has been sent the Hot Swappable Batteries field Shall be cleared. 6.4.6.4 Extended Alert Event Types The Extended Alert Event Type field provides extensions to the available types for the Alert Message. If the Extended Alert Event Type bit is not set, then the Extended Alert Event Type is Reserved and Shall be set to zero. 6.4.6.4.1 Power State Change The Power state change event value May be set when the DFP transitions into a new power state. The new power state Shall be communicated via the Power state change byte in the Status Message. This Message Should be sent by the host in response to any system power state change. 6.4.6.4.2 Power Button Press The Power button press event value May be set when the power button on the UFP is pressed. The press and release events are separated into two different events so that devices that respond differently to a long button press will see a long button press. On the host-side, the power button press event typically initiates the same behavior as a power button press of the host's power button. 6.4.6.4.3 Power Button Release If a Power button press event was sent, then the Power button release event value Shall be sent by the UFP following the Power button press event. If a physical power button press initiated the Power button press event, then the Power button release event Should be sent when the physical button is released. 6.4.6.4.4 Controller Initiated Wake The Controller initiated wake is used to communicate a wake event from the UFP to the DPF such as Wake on LAN from a NIC or another controller. This event doesn't need the press/release form of the Power button press, because it only needs to communicate the presence of the event, and not the timing. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 201 6.4.7 Get_Country_Info Message The Get_Country_Info Message Shall be sent by a Port to get country specific information from its Port Partner using the country's Alpha-2 Country Code defined by [ISO 3166]. The Port Partner responds with a Country_Info Message that contains the country specific information. The Get_Country_Info Message Shall be as shown in Figure 6.30, "Get_Country_Info Message" and Table 6.48, "Country Code Data Object (CCDO)". For example, if the request is for China information, then the Country Code Data Object (CCDO) would be CCDO [31:0] = 434E0000h for "CN" country code. Figure 6.30 Get_Country_Info Message Table 6.48 Country Code Data Object (CCDO) Bit(s) Description B31…24 First character of the Alpha-2 Country Code defined by [ISO 3166] B23…16 Second character of the Alpha-2 Country Code defined by [ISO 3166] B15…0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 CCDO Page 202 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8 Enter_USB Message The Enter_USB Message Shall be sent by the DFP to its UFP Port Partner and to the Cable Plug(s) of an Active Cable, when in an Explicit Contract, to enter a specified USB Mode of operation. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). When entering [USB4] operation, the Enter_USB Message Shall be sent by a [USB4] PDUSB Hub's DFP(s) or [USB4] PDUSB Host's DFP(s) within tEnterUSB:  following a PD Connection.  after a Data Reset to enter [USB4] operation is completed.  after a Data Role Swap is completed. The Enter_USB Message May be sent by a PDUSB Hub's DFP(s) or PDUSB Host's DFP(s) within tEnterUSB following a PD Connection or after a Data Reset to enter [USB 3.2] or [USB 2.0] operation. The Enter_USB Message Shall be used by a PDUSB Hub's DFP(s) to speculatively train the USB links or enter [DPTC2.1] or [TBT3] Alternate Modes prior to the presence of a host. In this case, the Host Present bit Shall be cleared. When the Host is Connected the Enter_USB Message Shall be resent with the Host Present bit set. The Enter_USB Message's Enter USB Data Object (EUDO), received from the Root Hub when the USB Host is connected, Shall be propagated down through the Hub tree. See [USB Type-C 2.4] USB4® Hub Connection Requirements. The Enter_USB Message Shall be as shown in Figure 6.31, "Enter_USB Message" and Table 6.49, "Enter_USB Data Object (EUDO)". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 203 Figure 6.31 Enter_USB Message Table 6.49 Enter_USB Data Object (EUDO) Bit(s) Field Description B31 Reserved Shall be set to zero. B30…28 USB Mode 1  000b:  001b:  010b:  111b…011b: Reserved, Shall Not be used. B27 Reserved Shall be set to zero. B26 USB4 DRD 2  0b: Not capable of operating as a [USB4] Device  1b: Capable of operating as a [USB4] Device B25 USB3 DRD 2  0b: Not capable of operating as a [USB 3.2] Device  1b: Capable of operating as a [USB 3.2] Device B24 Reserved Shall be set to zero. B23…21 Cable Speed 2,3  000b: [USB 2.0]only, no SuperSpeed support  001b: [USB 3.2] Gen1  010b: [USB 3.2]Gen2 and [USB4] Gen2  011b: [USB4] Gen3  100b: [USB4] Gen4  101b…111b: Reserved, Shall Not be used. B20…19 Cable Type 2,3  00b: Passive  01b: Active Re-timer  10b: Active Re-driver  11b: Optically Isolated B18…17 Cable Current 2  00b = VBUS is not supported  01b = Reserved  10b = 3A  11b = 5A B16 PCIe Support 2 [USB4] PCIe tunneling supported by the host B15 DP Support 2 [USB4] DP tunneling supported by the host B14 TBT Support 2 [TBT3] is supported by the host’s USB4® Connection Manager B13 Host Present 2 A Host is present at the top of the USB tree. When this bit is set PCIe Support, DP Support and TBT Support represent the Host’s Capabilities that Shall be propagated down the Hub tree. B12…0 Reserved Shall be set to zero. 1) Entry into [USB 3.2] and [USB4] include entry into [USB 2.0]. 2) Shall be Ignored when received by a Cable Plug (e.g., SOP’ or SOP’’). 3) The DFP Shall interpret the Cable Plug’s reported capability as defined in [USB Type-C 2.4] in the USB4 Discovery and Entry Section. Header No. of Data Objects = 1 EUDO Page 204 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8.1 USB Mode Field The USB Mode field Shall be used by the DFP to direct the USB Mode the Port Partner is to enter. 6.4.8.2 USB4® DRD Field The USB4 DRD field Shall be set when the Host DFP is capable of operating as a [USB4] Device. A [USB4] Host DFP that sets the USB4 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.3 USB3 DRD Field The USB3 DRD field Shall be set when the Host DFP is capable of operating as a [USB 3.2] Device. A [USB 3.2] Host DFP that sets the USB3 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.4 Cable Speed Field The Cable Speed field Shall be used to indicate the cable's maximum speed. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.5 Cable Type Field The Cable Type field Shall be used to indicate whether the cable is passive or active. Further if the cable is active, it indicates the type of active circuits in the cable and if the cable is optically isolated. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.6 Cable Current Field The Cable Current field Shall be used to indicate the cable's current carrying capability. The value is reported by the Cable Plug in the VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field. 6.4.8.7 PCIe Support Field The PCIe Support field Shall be set when the Host DFP is capable of tunneling PCIe over [USB4]. The PCIe Support field May be set speculatively when the Hub's DFP is capable of tunneling PCIe over [USB4]. 6.4.8.8 DP Support Field The DP Support field Shall be set when the Host DFP is capable of tunneling DP over [USB4]. The DP Support field May be set speculatively when the Hub's DFP is capable of tunneling DP over [USB4]. 6.4.8.9 TBT Support Field The TBT Support field Shall be set when the Host DFP is capable of tunneling ThunderboltTM over [USB4] and that the Connection Manager (CM) supports discovery and configuration of Thunderbolt 3 devices connected to the DFP of [USB4] Hubs. The TBT Support field May be set speculatively when the Hub's DFP is capable of tunneling Thunderbolt over [USB4]. 6.4.8.10 Host Present Field The Host Present field Shall be set to indicate that a Host is present upstream. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 205 6.4.9 EPR_Request Message An EPR_Request Message Shall be sent by a Sink, operating in EPR Mode, to request power, typically during the request phase of a power Negotiation. The EPR_Request Message Shall be sent in response to the most recent EPR_Source_Capabilities Message. The EPR_Request Message Shall return a Sink Request Data Object (RDO) that Shall identify the Power Data Object being requested followed by a copy of the Power Data Object being requested. Note: The requested Power Data Object May be either an EPR (A)PDO or SPR (A)PDO. The EPR_Request Message Shall be as shown in Figure 6.32, "EPR_Request Message". Figure 6.32 EPR_Request Message The Source Shall verify the PDO in the EPR_Request Message exactly matches the PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO. The Source Shall respond to an EPR_Request Message in the same manner as it responds to a Request Message with an Accept Message, or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Explicit Contract Negotiation process for EPR is the same as the process for SPR Mode except that the Source_Capabilities Message is replaced by the EPR_Source_Capabilities and the Request Message is replaced by the EPR_Request Message. An EPR Source operating in SPR Mode that receives a EPR_Request Message Shall initiate a Hard Reset. The RDO takes a different form depending on the kind of power requested. The PDO and APDO formats are detailed in Section 6.4.2, "Request Message". Header No. of Data Objects = 2 RDO Copy of PDO Page 206 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.10 EPR_Mode Message The EPR_Mode Message is used to enter, acknowledge, and exit the EPR Mode. The Action field is used to describe the action that is to be taken by the recipient of the EPR_Mode Message. The Data field provides additional information for the Message recipient in the EPR Mode Data Object (ERMDO). The EPR_Mode Message Shall be as shown in Figure 6.33, "EPR Mode DO Message" and Table 6.50, "EPR Mode Data Object (EPRMDO)". Figure 6.33 EPR Mode DO Message 6.4.10.1 Process to enter EPR Mode An EPR Source Shall enter EPR Mode upon request by an EPR Sink connected with an EPR Cable when able to offer the Source Capabilities as defined in the Power Rules (See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable"). For Port Partners to successfully enter EPR Mode, the following conditions must be met:  The Sink Shall request entry into the EPR Mode. Table 6.50 EPR Mode Data Object (EPRMDO) Bit(s) Field Description B31…24 Action Value Action Sent By 0x00 Reserved and Shall Not be used. 0x01 Enter Sink only 0x02 Enter Acknowledged Source only 0x03 Enter Succeeded Source only 0x04 Enter Failed Source only 0x05 Exit Sink or Source 0x06…0xFF Reserved and Shall Not be used. B23...16 Data Action Field Data Field Value Enter Shall be set to the EPR Sink Operational PDP Enter Acknowledged Shall be set to zero Enter Succeeded Shall be set to zero Enter Failed Shall be one of the following values:  0x00 - Unknown cause  0x01 - Cable not EPR Capable  0x02 –Source failed to become VCONN Source.  0x03 – EPR Capable bit not set in RDO.  0x04 – Source unable to enter EPR Mode1.  0x05 - EPR Capable bit not set in PDO. All other values are Reserved and Shall Not be used Exit Shall be set to zero B15...0 Reserved Shall be set to zero 1) The Sink May retry entering EPR Mode after receiving this Enter Failed response. Header No. of Data Objects = 1 EPRMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 207  The Source Shall verify the cable is EPR Capable.  A Sink Shall Not be Connected to the Source through a Charge Through VPD (CT-VPD).  The Source and Sink Shall already be in an SPR Explicit Contract.  The EPR Capable bit Shall be set in the Fixed Supply 5V PDO.  The EPR Capable bit Shall have been set in the RDO in the last Request Message received by the Source. To verify the cable is EPR Capable, the EPR Source Shall have already done the following (see Section 6.6.21.4, "tEPRSourceCableDiscovery"):  Discover the cable prior to entering its First Explicit Contract  Alternatively, within tEPRSourceCableDiscovery of entry into the First Explicit Contract  If it is the VCONN Source, discover the cable.  If not the VCONN Source, do a VCONN Swap then discover the cable. and can verify the cable is EPR Capable by completing steps 5 and 6 in the entry process in Figure 6.34, "Illustration of process to enter EPR Mode". The EPR Mode entry process is a Non-interruptible multi-Message AMS. An illustration of this AMS is shown in Figure 6.34, "Illustration of process to enter EPR Mode". Note: Figure 6.34, "Illustration of process to enter EPR Mode" is not Normative but is Informative only. Page 208 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.34 Illustration of process to enter EPR Mode The entry process Shall follow these steps in order: 1) The Sink Shall send the EPR_Mode Message with the Action field set to 1 (Enter) and the Data field set to its Operational PDP. If the EPR Source receives an EPR_Mode Message with the Action field not set to Enter it Shall initiate a Soft Reset. 2) The Source Shall do the following: EPR_Mode Enter #1 Start SPR Mode EPR Mode Sink Source Cable EPR Entry process SPR contract in place #2.a Sink EPR Capable? Abort EPR Entry Send Entry Failed – Sink not EPR Capable #2.b Source EPR Capable? Abort EPR Entry Send Entry Failed – Source not EPR Capable #2.c Source EPR Capable Now? Abort EPR Entry Send Entry Failed – Source unable to enter EPR #2.d Send EPR Ack #3 Received EPR Ack? #4 Known Cable? #7 Send Enter Succeeded N N N N N #5 Is VCONN Source? #8 Received Enter successful? N Error Send Soft Reset #6.a-d EPR Cable? Abort EPR Entry Send Entry Failed – Source not VCONN Source N Y Y Y Y EPR_MODE Enter Succeeded Y Y Y #5 Is VCONN Source? N #5 VCONN Swap N Abort EPR Entry Send Entry Failed – Not EPR Cable Y Y #4 EPR Capable? Y N Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 209 a) Verify the EPR Capable bit was set in the most recent RDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 3 ("EPR Mode Capable bit not set in the RDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. b) Verify the EPR Capable bit was set in the most recent 5V Fixed Supply PDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 5 ("EPR Mode Capable bit not set in the Fixed Supply 5V PDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. c) Verify the Source is still able to support EPR Mode. If not, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and Data field set to 4 ("Unable at this time"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. The Sink May at some time in the future send another request to enter EPR Mode. d) Send an EPR_Mode Message with the Action field set to 2 (Enter Acknowledged). 3) If the Sink receives any Message, other than an EPR_Mode Message with the Action Field set to 2, the Sink Shall initiate a Soft Reset. 4) When the EPR Source has used the Discover Identity Command to determine and remembers the Cable Capabilities or the EPR Source is connected with a captive cable: a) If the cable is EPR Capable it Should go directly to Step 7, but May continue to Step 5. b) If the cable is not EPR Capable it Shall do the following: c) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 1 ("Cable not EPR capable"). d) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 5) If the Source is not the VCONN Source, it Shall send a VCONN_Swap Message a) If the Source fails to become the VCONN Source, it Shall: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 2 (not VCONN Source). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 6) The Source Shall use the Discover Identity Command to read the cable's e-Marker and verify the following: a) Cable VDO - Maximum VBUS Voltage (Passive Cable)/Maximum VBUS Voltage (Active Cable) field is 11b (50V) b) Cable VDO - VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field is 10b (5A) c) Cable VDO - EPR Capable (Passive Cable)/EPR Capable (Active Cable) field is 1b (EPR Capable) d) If the cable fails to respond to the Discover Identity Command or is not EPR Capable, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field to1 ("Cable not EPR capable"). Page 210 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 7) The Source Shall send the EPR_Mode Message with the Action field set to 3 (Enter Succeeded) and Shall enter EPR Mode. 8) If the Sink receives an EPR_Mode Message with the Action field set to 3 (Enter Succeeded) it Shall enter EPR Mode, otherwise it Shall initiate a Soft Reset. If the EPR Mode entry process successfully completes within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Source Shall send an EPR_Source_Capabilities Message within tFirstSourceCap. If the EPR Mode entry process has not been aborted or does not complete within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Sink Shall initiate a Soft Reset. 6.4.10.2 Operation in EPR Mode While operating in EPR Mode, the Source Shall only send EPR_Source_Capabilities Messages to Advertise its power Capabilities and the Sink Shall only respond with EPR_Request Messages to Negotiate Explicit Contracts. The EPR_Request Message May be for either an SPR or EPR (A)PDO. If the Source sends a Source_Capabilities Message, that is not in response to a Sink Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. If the Sink sends a Request Message, the Source Shall initiate a Hard Reset. The Source Shall monitor the CC communications path to ensure that there is periodic traffic. The Sink Shall send an EPR_KeepAlive Message when it has not sent any Messages for more than tSinkEPRKeepAlive to ensure there is timely periodic traffic. If there is no traffic for more than tSourceEPRKeepAlive, the Source Shall initiate a Hard Reset. 6.4.10.3 Exiting EPR Mode 6.4.10.3.1 Commanded Exit While in EPR Mode, either the Source or Sink May exit EPR Mode by sending an EPR_Mode Message with the Action field set to 5 (Exit). The ports Shall be in an Explicit Contract with an SPR (A)PDO prior to the EPR Mode exit process by either:  The Source sending an EPR_Source_Capabilities Message with no EPR (A)PDO s (e.g., only SPR (A)PDO s) or  The Sink negotiating a new Explicit Contract with bit 31 in the RDO set to zero (e.g., only SPR (A)PDO s)). The process to exit EPR Mode is a Non-interruptible multi-Message AMS and Shall follow these steps in order: 1) The Port Partners Shall be in an Explicit Contract with an SPR (A)PDO. 2) Either the Source or Sink Shall send an EPR_Mode Message with the Action field set to 5 (Exit) to exit the EPR Mode 3) The Source Shall send a Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit). 4) If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap of the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit), Sink Shall initiate a Hard Reset. 6.4.10.3.2 Implicit Exit EPR Mode Shall be exited as the side-effect of the Power Role Swap and Fast Role Swap processes. This is because at the end of these processes VBUS will be at vSafe5V and the Ports will be in an Implicit Contract. The New Source will then send a Source_Capabilities Message (not an EPR_Source_Capabilities Message) to begin the process of Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 211 negotiating an SPR Explicit Contract. Once an SPR Explicit Contract is entered, the Source and Sink can then enter EPR Mode if needed. 6.4.10.3.3 Exits due to errors Other critical errors can occur while in EPR Mode; these errors Shall result in Hard Reset being initiated by the Port that detects the error. Some of these errors include:  An EPR_Mode Message with the Action field set to 5 (Exit) to exit EPR Mode is received by a Port in an Explicit Contract with an EPR (A)PDO.  The Sink receives an EPR_Source_Capabilities Message with an EPR (A)PDO in any of the first seven object positions.  The (A)PDO in the EPR_Request Message does not match the (A)PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO.  The Source receives a Request Message.  The Sink receives a Source_Capabilities Message not in response to a Get_Source_Cap Message. Page 212 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.11 Source_Info Message The Source_Info Message Shall be sent in response to a Get_Source_Info Message. The Source_Info Message contains one Source Information Data Object (SIDO). The Source_Info Message returns a SIDO whose format Shall be as shown in Figure 6.35, "Source_Info Message" and Table 6.51, "Source_Info Data Object (SIDO)". The Number of Data Objects field in the Source_Info Message Shall be set to 1. The Port Maximum PDP, Port Present PDP, Port Reported PDP and the Port Type are used to identify Capabilities of a Source Port. Figure 6.35 Source_Info Message 6.4.11.1 Port Type Field Port Type is a Static field that Shall be used to indicate whether the amount of power the Port can provide is fixed or can change dynamically. For Ports that are part of a Shared Capacity Group, the Port Type field Shall be set to Managed Capability Port. For Ports not part of a Shared Capacity Group, the Port Type field May be set to either Managed Capability Port or Guaranteed Capability Port. 6.4.11.2 Port Maximum PDP Field Port Maximum PDP is a Static field that Shall report the integer portion of the PDP Rating of the Port. A Guaranteed Capability Port (as indicated by the Port Type field being set to '1') Shall always be capable of supplying this amount of power. A Managed Capability Port (as indicated by the Port Type field being set to '0') Shall be able to offer this amount of power at some time. The Port Maximum PDP Shall be the same as the larger of the SPR Source PDP Rating and the EPR Source PDP Rating in the Source_Capabilities_Extended Message. 6.4.11.3 Port Present PDP Field The Port Present PDP field Shall indicate the integer part of the amount of power the Port is presently capable of supplying including limitations due to Cable Capabilities or abnormal operating conditions (e.g., elevated temperature, low input voltage, etc.). A Guaranteed Capability Port Shall always set its Port Present PDP to be the same as its Port Maximum PDP or the highest possible value when limited. Table 6.51 Source_Info Data Object (SIDO) Bit(s) Field Description B31 Port Type  0 = Managed Capability Port  1 = Guaranteed Capability Port B30…24 Reserved Shall be set to zero B23...16 Port Maximum PDP Power the Port is designed to supply B15…8 Port Present PDP Power the Port is presently capable of supplying B7…0 Port Reported PDP Power the Port is actually advertising Header No. of Data Objects = 1 SIDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 213 A Managed Capability Port that is part of a Shared Capacity Group Shall set its Port Present PDP to Shared Port Power Available as defined in [USB Type-C 2.4] or to a lower value when limited. A Managed Capability Port that is part of an Assured Capacity Group Shall set its Port Present PDP to the Port Maximum PDP or the highest value possible when limited. 6.4.11.4 Port Reported PDP Field The Port Reported PDP field Shall track the amount of power the Port is offering in its Source_Capabilities Message or EPR_Source_Capabilities Message. The Port Reported PDP field May be dynamic or Static depending on the Port's other characteristics such as Managed/Guaranteed Capability, SPR/EPR Mode, its power policy etc. Note: The Port Reported PDP field is computed as the integer part of, the largest of the products of the voltage times current of the Fixed Supply PDOs returned in the Source_Capabilities Message or EPR_Source_Capabilities Messages. Page 214 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.12 Revision Message The Revision Message Shall be sent in response to the Get_Revision Message sent by the Port Partner. This Message is used to identify the highest Revision the Port is capable of operating at. The Revision Message contains one Revision Message Data Object (RMDO). The Revision Message returns an RMDO whose format Shall be as shown in Figure 6.36, "Revision Message Data Object"and Table 6.52, "Revision Message Data Object (RMDO)". The Number of Data Objects field in the Revision Message Shall be set to 1. Figure 6.36 Revision Message Data Object E.g., for Revision 3.2, Version 1.1 the fields would be the following:  Revision.major = 0011b  Revision.minor = 0010b  Version.major = 0001b  Version.minor = 0001b Table 6.52 Revision Message Data Object (RMDO) Bit(s) Description B31…28 Revision.major B27…24 Revision.minor B23...20 Version.major B19...16 Version.minor B15...0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 RMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 215 6.5 Extended Message An Extended Message Shall contain an Extended Message Header (indicated by the Extended field in the Message Header being set) and be followed by zero or more data bytes. Additional bytes that might be added to existing Messages in future Revision of this specification Shall be Ignored. The format of the Extended Message is defined by the Message Header's Message Type field and is summarized in Table 6.53, "Extended Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.53 Extended Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0 0000 Reserved All values not explicitly defined are Reserved and Shall Not be used. 0 0001 Source_Capabilities_Extended Source or Dual-Role Power See Section 6.5.1 SOP only 0 0010 Status Source, Sink or Cable Plug See Section 6.5.2 SOP* 0 0011 Get_Battery_Cap Source or Sink See Section 6.5.3 SOP only 0 0100 Get_Battery_Status Source or Sink See Section 6.5.4 0 0101 Battery_Capabilities Source or Sink See Section 6.5.5 SOP only 0 0110 Get_Manufacturer_Info Source or Sink See Section 6.5.6 SOP* 0 0111 Manufacturer_Info Source, Sink or Cable Plug See Section 6.5.7 SOP* 0 1000 Security_Request Source or Sink See Section 6.5.8.1 SOP* 0 1001 Security_Response Source, Sink or Cable Plug See Section 6.5.8.2 SOP* 0 1010 Firmware_Update_Request Source or Sink See Section 6.5.9.1 SOP* 0 1011 Firmware_Update_Response Source, Sink or Cable Plug See Section 6.5.9.2 SOP* 0 1100 PPS_Status Source See Section 6.5.10 SOP only 0 1101 Country_Info Source or Sink See Section 6.5.12 SOP only 0 1110 Country_Codes Source or Sink See Section 6.5.11 SOP only 0 1111 Sink_Capabilities_Extended Sink or Dual-Role Power See Section 6.5.13 SOP only 1 0000 Extended_Control Source or Sink See Section 6.5.14 SOP only 1 0001 EPR_Source_Capabilities Source or Dual-Role Power See Section 6.5.15.2 SOP only 1 0010 EPR_Sink_Capabilities Sink or Dual-Role Power See Section 6.5.15.3 SOP only 1 0011... 1 1101 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 1110 Vendor_Defined_Extended Source, Sink or Cable Plug See Section 6.5.16 SOP* 1 1111 Reserved All values not explicitly defined are Reserved and Shall Not be used. Page 216 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1 Source_Capabilities_Extended Message The Source_Capabilities_Extended Message Should be sent in response to a Get_Source_Cap_Extended Message. The Source_Capabilities_Extended Message enables a Source or a DRP to inform the Sink about its Capabilities as a Source. The Source_Capabilities_Extended Message Shall return a 25-byte Source Capabilities Extended Data Block (SCEDB) whose format Shall be as shown in Figure 6.37, "Source_Capabilities_Extended Message" andTable 6.54, "Source Capabilities Extended Data Block (SCEDB)". Figure 6.37 Source_Capabilities_Extended Message Table 6.54 Source Capabilities Extended Data Block (SCEDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 XID Value provided by the USB-IF assigned to the product 8 FW Version Firmware version number 9 HW Version Hardware version number 10 Voltage Regulation Bit Description 1…0  00b: 150mA/µs Load Step (default)  01b: 500mA/µs Load Step  11b…10b: Reserved and Shall Not be used. 2  0b: 25% IoC (default)  1b: 90% IoC 3…7 Reserved and Shall Not be used 11 Holdup Time Output will stay with regulated limits for this number of milliseconds after removal of the AC from the input.  0x00 = feature not supported Note: A value of at least 3ms Should be used (see Section 7.1.12.2, "Holdup Time Field"). 12 Compliance Compliance in SPR Mode: Bit Description 0 LPS compliant when set 1 PS1 compliant when set 2 PS2 compliant when set 3…7 Reserved and Shall Not be used 13 Touch Current Bit Description 0 Low touch current EPS when set 1 Ground pin supported when set 2 Ground pin intended for protective earth when set 3...7 Reserved and Shall Not be used Extended Header Data Size = 25 SCEDB (25-byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 217 6.5.1.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Source's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 14 Peak Current1 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 16 Peak Current2 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 18 Peak Current3 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 20 Touch Temp Temperature conforms to:  0 = [IEC 60950-1] (default)  1 = [IEC 62368-1] TS1  2 = [IEC 62368-1] TS2 Note: All other values Reserved and Shall Not be used. 21 Source Inputs Bit Description 0  0b: No external supply  1b: External supply present 1 If bit 0 is set:  0b: External supply is constrained.  1b: External supply is unconstrained. If bit 0 is not set Reserved and Shall be set to zero 2  0b: No internal Battery  1b: Internal Battery present 3...7 Reserved and Shall be set to zero 22 Number of Batteries/ Battery Slots Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 23 SPR Source PDP Rating 0…6: Source PDP Rating (EPR Source’s PDP Rating when operating in SPR Mode. 7: Reserved and Shall be set to zero 24 EPR Source PDP Rating 0…7: EPR Source PDP Rating Table 6.54 Source Capabilities Extended Data Block (SCEDB) (Continued) Offset Field Description Page 218 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Source's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.1.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.1.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.1.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.1.6 Voltage Regulation Field The Voltage Regulation field contains bits covering Load Step Slew Rate and Magnitude. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.1.6.1 Load Step Slew Rate The Source Shall report its load step response capability in bits 0…1 of the Voltage Regulation bit field. 6.5.1.6.2 Load Step Magnitude The Source Shall report its load step magnitude rate as a percentage of IoC in bit 2 of the Voltage Regulation field. 6.5.1.7 Holdup Time Field The Holdup Time field Shall contain the Source's holdup time (see Section 7.1.12.2, "Holdup Time Field"). 6.5.1.8 Compliance Field The Compliance is Static and Shall contain the standards the Source is compliant with in SPR (see Section 7.1.12.3, "Compliance Field"). 6.5.1.9 Touch Current Field The Touch Current field reports whether the Source meets certain leakage current levels and if it has a ground pin. A Source Shall set the Touch Current bit (bit 0) when their leakage current is less than 65µA rms when Source's maximum capability is less than or equal to 30W, or when their leakage current is less than 100 µA rms when its power capability is between 30W and 100W. The total combined leakage current Shall be measured in accordance with [IEC 60950-1] when tested at 250VAC rms at 50 Hz. A Source with a ground pin Shall set the Ground pin bit (bit 1). A Source whose Ground pin is intended to be connected to a protective earth Shall set both bit1 and bit 2. 6.5.1.10 Peak Current Field The Peak Current1/Peak Current2/Peak Current3 fields Shall contain the combinations of Peak Current that the Source supports (see Section 7.1.12.4, "Peak Current"). Peak Current provides a means for Source report its ability to provide current in excess of the Negotiated amount for short periods. The Peak Current descriptor defines up to three combinations of% overload, duration and duty Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 219 cycle defined as Peak Current1, Peak Current2 and Peak Current3 that the Source supports. A Source May offer no Peak Current capability. A Source Shall populate unused Peak Current bit fields with zero. The Bit Fields within Peak Current1, Peak Current2 and Peak Current3 contain the following subfields:  Percentage Overload  Shall be the maximum peak current reported in 10% increments as a percentage of the Negotiated operating current (IoC) offered by the Source. Values higher than 25 (11001b) are clipped to 250%.  Overload Period  Shall be the minimum rolling average time window in 20ms increments, where a value of 20ms is recommended.  Duty Cycle  Shall be the maximum percentage of overload period reported in 5% increments. The values Should be 5%, 10% and 50% for PeakCurrent1, PeakCurrent2, and PeakCurrent3, respectively.  VBUS Droop  Shall be set to one to indicate there is an additional 5% voltage droop on VBUS when the overload conditions occur as defined by vSrcPeak. However, it is recommended that the Source Should pro- vide VBUS in the range of vSrcNew when overload conditions occur and set this bit to zero. 6.5.1.11 Touch Temp Field The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Source's enclosure. Safety limits for the Source's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Source May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.1.12 Source Inputs Field The Source Inputs field Shall identify the possible inputs that provide power to the Source:  When bit 0 is set, the Source can be sourced by an external power supply.  When bits 0 and 1 are set, the Source can be sourced by an external power supply which is assumed to be effectively "infinite" i.e., it won't run down over time.  When bit 2 is set the Source can be sourced by an internal Battery. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. Note: Bit 2 May be set independently of bits 0 and 1. 6.5.1.13 Number of Batteries/Battery Slots Field The Number of Batteries/Battery Slots field Shall report the number of Fixed Batteries and Hot Swappable Battery Slots the Source supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. A Source Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 220 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.14 SPR Source PDP Rating Field For an SPR Source the SPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an EPR Source, the SPR Source PDP Rating field Shall report the integer portion of the maximum amount of power that the Port is designed to deliver in SPR Mode. The SPR Source PDP Rating field that is reported Shall be Static. 6.5.1.15 EPR Source PDP Rating Field For an EPR Source the EPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an SPR Source this field Shall be set to zero. The EPR Source PDP Rating field that is reported Shall be Static. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 221 6.5.2 Status Message The Status Message Shall be sent in response to a Get_Status Message. The content of the Status Message depends on the target of the Get_Status Message. When sent to SOP the Status Message returns the status of the Port's Port Partner. When sent to SOP’ or SOP’’ the Status Message returns the status of one of the Active Cable's Cable Plugs. 6.5.2.1 SOP Status Message A Status Message, sent in response to Get_Status Message to SOP, enables a Port to inform its Port Partner about the present status of the Source or Sink. Typically, a Get_Status Message will be sent by the Port after receipt of an Alert Message. Some of the reported events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Status Message returns a 7-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.38, "SOP Status Message" and Table 6.55, "SOP Status Data Block (SDB)". Figure 6.38 SOP Status Message Table 6.55 SOP Status Data Block (SDB) Offset (Byte) Field Description 0 Internal Temp Source or Sink’s internal temperature in °C  0 = feature not supported  1 = temperature is less than 2°C.  2-255 = temperature in °C. 1 Present Input Bit Description 0 Reserved and Shall be set to zero 1 External Power when set 2 External Power AC/DC (Valid when Bit 1 set)  0: DC  1: AC Reserved when Bit 1 is zero 3 Internal Power from Battery when set 4 Internal Power from non-Battery power source when set 5...7 Reserved and Shall be set to zero 2 Present Battery Input When Present Input field bit 3 set Shall contain the bit corresponding to the Battery or Batteries providing power:  Upper nibble = Hot Swappable Battery (b7…4)  Lower nibble = Fixed Battery (b3…0) When Present Input field bit 3 is not set this field is Reserved and Shall be set to zero. Extended Header Data Size = 7 SDB (7-byte block) Page 222 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 3 Event Flags Bit Flag Description 0 Reserved and Shall be set to zero 1 OCP Event OCP event when set 2 OTP Event OTP event when set 3 OVP Event OVP event when set 4 CL/CV Mode In PPS Mode only: CL mode when set, CV mode when cleared 5...7 Reserved and Shall be set to zero 4 Temperature Status Bit Description 0 Reserved and Shall be set to zero 1...2  00 – Not Supported.  01 – Normal  10 – Warning  11 – Over temperature 3...7 Reserved and Shall be set to zero 5 Power Status Bit Description 0 Reserved and Shall be set to zero 1 Source power limited due to cable supported current 2 Source power limited due to insufficient power available while sourcing other ports 3 Source power limited due to insufficient external power 4 Source power limited due to Event Flags in place (Event Flags must also be set) 5 Source power limited due to temperature 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 223 6.5.2.1.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of a portion of the Source or Sink. 6.5.2.1.2 Present Input Field The Present Input field indicates which supplies are presently powering the Source or Sink. The following bits are defined:  Bit 1: indicates that an external power source is present.  Bit 2: indicates whether the external unconstrained power source is AC or DC.  Bit 3: indicates that power is being provided from Battery.  Bit4: indicates an alternative internal source of power that is not a Battery. 6.5.2.1.3 Present Battery Input Field The Present Battery Input field indicates which Battery or Batteries are presently supplying power to the Source or Sink. The Present Battery Input field is only Valid when the Present Input field indicates that there is Internal Power from Battery. The upper nibble of the field indicates which Hot Swappable Battery/Batteries are supplying power with bit 4 in upper nibble corresponding to Battery 4 and bit 7 in the upper nibble corresponding to Battery 7 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). The lower nibble of the field indicates which Fixed Battery/Batteries are supplying power with bit 0 in lower nibble corresponding to Battery 0 and bit 3 in the lower nibble corresponding to Battery 3 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). 6 Power State Change Bit Description 0...2 New Power State Value Description 0 Status not supported 1 S0 2 Modern Standby 3 S3 4 S4 5 S5 (Off with battery, wake events supported) 6 G3 (Off with no battery, wake events not supported) 7 Reserved and Shall be set to zero 3...5 New Power State indicator Value Description 0 Off LED 1 On LED 2 Blinking LED 3 Breathing LED 4...7 Reserved and Shall be set to zero 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Page 224 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.1.4 Event Flags Field The Event Flags field returns event flags. The OTP, OVP and OCP event flags Shall be set when there is an event and Shall only be cleared when read with the Get_Status Message. When the OTP Event flag is set the Temperature Status field Shall also be set to over temperature. The CL/CV Mode flag is only Valid when operating as a Programmable Power Supply and Shall be Ignored otherwise. When the Source is operating as a Programmable Power Supply the CL/CV Mode flag Shall be set when operating in Current Limit mode (CL) and Shall be cleared when operating in Constant Voltage mode (CV). 6.5.2.1.5 Temperature Status Field The Temperature Status field returns the current temperature status of the device either: normal, warning or over temperature. When the Temperature Status field is set to over temperature the OTP Event flag Shall also be set. 6.5.2.1.6 Power Status Field The Power Status field indicates the current status of a Source. A non-zero return of the field indicates Advertised Source power is being reduced for either:  The cable does not support the full Source current.  The Source is supplying power to other ports and is unable to provide its full power.  The external power to the Source is insufficient to support full power.  An Event has occurred that is causing the Source to reduce its Advertised power. A Sink Shall set this field to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 225 6.5.2.1.7 Power state change The Power State Change field contains two status bytes; the New Power State and New Power State indicator status bytes. 6.5.2.1.7.1 New power state The New Power State status byte indicates a power state change to one of the specified power states. Any device that supports the ACPI standard system power states Shall use the ACPI states. For devices that do not support the ACPI power states, the following mapping Should be used:  High power (on) state -> S0  Sleep state -> S3  Low power (off) state -> S5 or G3 6.5.2.1.7.2 New power state indicator The New Power State indicator status byte defines the host's desired indicator for the specified power state. This indicator allows several possibilities for predefined behaviors that the host can specify to indicate its system power state to the user via the downstream device. The New Power State indicator is a "best effort" indicator. If the device cannot provide the requested indicator, then it provides the best indicator that it can. If a Breathing indicator cannot be provided, then a Blinking indicator Should be provided. If a Blinking indicator cannot be provided, then a constant on indicator Should be provided. New Power State indicators in decreasing precedence:  Breathing  Blinking  Constant on  No indicator Page 226 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.2 SOP'/SOP'' Status Message A Status Message, sent in response to a Get_Status Message to SOP’ or SOP’’, enables a Source or Sink to get the present status of the Cable's Cable Plug(s). Typically, a Get_Status Message will be used by the USB Host and/or USB Device to manage the Cable's Cable Plug(s) temperature. The Status Message returns a 2-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.39, "SOP'/SOP'' Status Message" and Table 6.56, "“SOP’/SOP’’ Status Data Block (SPDB)”". Passive Cable Plugs Shall Not indicate Thermal Shutdown. Figure 6.39 SOP'/SOP'' Status Message 6.5.2.2.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of the plug in °C. The internal temperature Shall be monotonic. The Cable Plug Shall report its internal temperature every tACTempUpdate. 6.5.2.2.2 Thermal Shutdown Field The Flags flag Shall also be set when the plug's internal temperature exceeds the Internal Maximum Temperature reported in the Active Cable VDO. Once this bit has been set, it Shall remain set and the plug Shall remain in Thermal Shutdown until there is a Hard Reset or the Active Cable's power is removed. The Thermal Shutdown flag Shall Not be cleared by a Cable Reset. Table 6.56 “SOP’/SOP’’ Status Data Block (SPDB)” Offset (Byte) Field Value Description 0 Internal Temp Unsigned Int Cable Plug’s internal temperature in °C.  0 = feature not supported  1 = temperature is less than 2°C.  2…255 = temperature in °C. 1 Flags Bit Field Bit Description 0 Thermal Shutdown 1...7 Reserved and Shall be set to zero Extended Header Data Size = 2 SPDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 227 6.5.3 Get_Battery_Cap Message The Get_Battery_Cap (Get Battery Capabilities) Message is used to request the capability of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Capabilities Message (see Section 6.5.5, "Battery_Capabilities Message") containing a Battery Capabilities Data Block (BCDB) for the targeted Battery. The Get_Battery_Cap Message contains a 1-byte Get Battery Cap Data Block (GBCDB), whose format Shall be as shown in Figure 6.40, "Get_Battery_Cap Message" and Table 6.57, "Get Battery Cap Data Block (GBCDB)". This block defines for which Battery the request is being made. The Data Size field in the Get_Battery_Cap Message Shall be set to 1. Figure 6.40 Get_Battery_Cap Message 6.5.4 Get_Battery_Status Message The Get_Battery_Status (Get Battery Status) Message is used to request the status of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Status Message (see Section 6.4.5, "Battery_Status Message") containing a Battery Status Data Object (BSDO) for the targeted Battery. The Get_Battery_Status Message contains a 1-byte Get Battery Status Data Block (GBSDB) whose format Shall be as shown in Figure 6.41, "Get_Battery_Status Message" and Table 6.58, "Get Battery Status Data Block (GBSDB)". This block contains details of the requested Battery. The Data Size field in the Get_Battery_Status Message Shall be set to 1. Figure 6.41 Get_Battery_Status Message Table 6.57 Get Battery Cap Data Block (GBCDB) Offset Field Description 0 Battery Cap Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Table 6.58 Get Battery Status Data Block (GBSDB) Offset Field Description 0 Battery Status Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Extended Header Data Size = 1 GBCDB Extended Header Data Size = 1 GBSDB Page 228 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.5 Battery_Capabilities Message The Battery_Capabilities Message is sent in response to a Get_Battery_Cap Message. The Battery_Capabilities Message contains one Battery Capability Data Block (BCDB) for one of the Batteries its supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BCDB Shall correspond to the Battery requested in the Battery Cap Ref field contained in the Get_Battery_Cap Message. The Battery_Capabilities Message returns a 9-byte BCDB whose format Shall be as shown in Figure 6.42, "Battery_Capabilities Message" and Table 6.59, "Battery Capability Data Block (BCDB)”". Figure 6.42 Battery_Capabilities Message 6.5.5.1 Vendor ID (VID) The VID field Shall contain the manufacturer VID associated with the Battery, as assigned by the USB-IF, or 0xFFFF in the case that no such VID exists. If the Battery Cap Ref field in the Get_Battery_Cap Message is Invalid, the VID field Shall be 0xFFFF. 6.5.5.2 Product ID (PID) The following rules apply to the PID field. When the VID: Table 6.59 Battery Capability Data Block (BCDB)” Offset (Byte) Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Battery Design Capacity Battery’s design capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = design capacity unknown 6 Battery Last Full Charge Capacity Battery’s last full charge capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = last full charge capacity unknown 8 Battery Type Bit Field Description 0 Invalid Battery Reference Invalid Battery reference when set. 1...7 --- Reserved Extended Header Data Size = 9 BCDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 229  Belongs to the Battery vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  Belongs to the Device vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor.  Is 0xFFFF the PID field Shall be set to 0x0000. 6.5.5.3 Battery Design Capacity Field The Battery Design Capacity field Shall return the Battery's design capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Design Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Design Capacity field Shall be set to 0xFFFF. 6.5.5.4 Battery Last Full Charge Capacity Field The Battery Last Full Charge Capacity field Shall contain the Battery's last full charge capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Last Full Charge Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Last Full Charge Capacity field Shall be set to 0xFFFF. 6.5.5.5 Battery Type Field The Battery Type field is used to report additional information about the Battery's Capabilities. 6.5.5.5.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Cap Message contains a reference to a Battery that does not exist. Page 230 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.6 Get_Manufacturer_Info Message The Get_Manufacturer_Info (Get Manufacturer Info) Message is sent by a Port to request manufacturer specific information relating to its Port Partner, Cable Plug or of a Battery behind a Port. The Port Shall respond by returning a Manufacturer_Info Message (Section 6.5.7, "Manufacturer_Info Message") containing a Manufacturer Info Data Block (MIDB). Support for this feature by the Cable Plug is Optional Normative. The Get_Manufacturer_Info Message contains a 2-byte Get Manufacturer Info Data Block (GMIDB). This block defines whether it is the Device or Battery manufacturer information being requested and for which Battery the request is being made. The Get_Manufacturer_Info Message returns a GMIDB whose format Shall be as shown in Figure 6.43, "Get_Manufacturer_Info Message" and Table 6.60, "Get Manufacturer Info Data Block (GMIDB)". Figure 6.43 Get_Manufacturer_Info Message Table 6.60 Get Manufacturer Info Data Block (GMIDB) Offset Field Description 0 Manufacturer Info Target  0: Port/Cable Plug  1: Battery  255…2: Reserved and Shall Not be used. 1 Manufacturer Info Ref If the Manufacturer Info Target field is Battery (01b) the Manufacturer Info Ref field Shall contain the Battery number reference which is the number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries. Otherwise, this field is Reserved and Shall be set to zero. Extended Header Data Size = 2 GMIDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 231 6.5.7 Manufacturer_Info Message The Manufacturer_Info Message Shall be sent in response to a Get_Manufacturer_Info Message. The Manufacturer_Info Message contains the USB VID and the Vendor's PID to identify the device or Battery and the device or Battery's manufacturer byte array in a variable length Data Block of up to MaxExtendedMsgLegacyLen. The Manufacturer_Info Message returns a Manufacturer Info Data Block (MIDB) whose format Shall be as shown in Figure 6.44, "Manufacturer_Info Message" and Table 6.61, "Manufacturer Info Data Block (MIDB)". Figure 6.44 Manufacturer_Info Message 6.5.7.1 Vendor ID (VID) If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the VID field Shall contain:  The manufacturer's VID associated with the Port/Cable Plug, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Device that has a USB data interface, the Device Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery, the VID field Shall contain:  The manufacturer VID associated with the Battery specified, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message:  Is Invalid, this VID field Shall be 0xFFFF.  Is Battery (01b) and the Manufacturer Info Ref field is Invalid, the VID field Shall be 0xFFFF. 6.5.7.2 Product ID (PID) If the VID is 0xFFFF, the PID field Shall contain 0x0000. Otherwise: Table 6.61 Manufacturer Info Data Block (MIDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Manufacturer String Vendor defined null terminated string of 0…21 characters. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string “Not Supported”. Extended Header Data Size = 5..26 MIDB Page 232 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the PID field Shall contain the device's 16-bit product identifier designated by the device vendor.  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery:  And the VID belongs to the Battery vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  And the VID belongs to the Device vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor. 6.5.7.3 Manufacturer String The Manufacturer String field Shall contain the device’s or Battery's manufacturer string as defined by the vendor. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string "Not Supported". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 233 6.5.8 Security Messages The authentication process between Port Partners or a Port and Cable Plug is fully described in [USBTypeCAuthentication 1.0]. This specification describes two Extended Messages used by the authentication process when applied to PD. In the authentication process described in [USBTypeCAuthentication 1.0] there are three basic exchanges that serve to:  Get the Port or Cable Plug's certificates.  Get the Port or Cable Plug's digest.  Challenge the Port Partner or Cable Plug. Certificates are used to convey information, attested to by a signer, which attests to the Port Partner's or Cable Plug's authenticity. The Port's or Cable Plug's certificates are needed when a Port encounters a Port Partner or Cable Plug it has not been Attached to before. To minimize calculations after the initial Attachment, a Port can also use a digest consisting of hashes of the certificates rather than the certificates themselves. Once the Port has the certificates and has calculated the hashes, it stores the hashes and uses the digest in future exchanges. After the Port gets the certificates or digest, it challenges its Port Partner or the Cable Plug to detect replay attacks. For further details refer to [USBTypeCAuthentication 1.0]. 6.5.8.1 Security_Request The Security_Request Message is used by a Port to pass a security data structure to its Port Partner or a Cable Plug. The Security_Request Message contains a Security Request Data Block (SRQDB) whose format Shall be as shown in Figure 6.45, "Security_Request Message". The contents of the SRQDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.45 Security_Request Message 6.5.8.2 Security_Response The Security_Response Message is used by a Port or Cable Plug to pass a security data structure to the Port that sent the Security_Request Message. The Security_Response Message contains a Security Response Data Block (SRPDB) whose format Shall be as shown in Figure 6.46, "Security_Response Message". The contents of the SRPDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.46 Security_Response Message Extended Header Data Size = 4..260 SRQDB Extended Header Data Size = 4..260 SRPDB Page 234 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.9 Firmware Update Messages The firmware update process between Port Partners or a Port and Cable Plug is fully described in [USBPDFirmwareUpdate 1.0]. This specification describes two Extended Messages used by the firmware update process when applied to PD. 6.5.9.1 Firmware_Update_Request The Firmware_Update_Request Message is used by a Port to pass a firmware update data structure to its Port Partner or a Cable Plug. The Firmware_Update_Request Message contains a Firmware Update Request Data Block (FRQDB) whose format Shall be as shown in Figure 6.47, "Firmware_Update_Request Message". The contents of the FRQDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.47 Firmware_Update_Request Message 6.5.9.2 Firmware_Update_Response The Firmware_Update_Response Message is used by a Port or Cable Plug to pass a firmware update data structure to the Port that sent the Firmware_Update_Request Message. The Firmware_Update_Response Message contains a Firmware Update Response Data Block (FRPDB) whose format Shall be as shown in Figure 6.48, "Firmware_Update_Response Message". The contents of the FRPDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.48 Firmware_Update_Response Message Extended Header Data Size = 4..260 FRQDB Extended Header Data Size = 4..260 FRPDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 235 6.5.10 PPS_Status Message The PPS_Status Message Shall be sent in response to a Get_PPS_Status Message. The PPS_Status Message enables a Sink to query the Source to get additional information about its operational state. The Get_PPS_Status Message and the PPS_Status Message Shall only be supported when the Alert Message is also supported. The PPS_Status Message Shall return a 4-byte PPS Status Data Block (PPSSDB) whose format Shall be as shown in Figure 6.49, "PPS_Status Message" and Table 6.62, "PPS Status Data Block (PPSSDB)". Figure 6.49 PPS_Status Message 6.5.10.1 Output Voltage Field The Output Voltage field Shall return the Source's output voltage at the time of the request. The output voltage is measured either at the Source's receptacle or, if the Source has a captive cable, where the voltage is applied to the cable. The measurement accuracy Shall be +/-3% rounded to the nearest 20mV in SPR PPS Mode. If the Source does not support the Output Voltage field, the field Shall be set to 0xFFFF. 6.5.10.2 Output Current Field The Output Current field Shall return the Source's output current at the time of the request measured at the Source's receptacle. The measurement accuracy Shall be +/-150mA. If the Source does not support the Output Current field, the field Shall be set to 0xFF. Table 6.62 PPS Status Data Block (PPSSDB) Offset (Byte) Field Description 0 Output Voltage 2 Source’s output voltage in 20mV units. When set to 0xFFFF, the Source does not support this field. 2 Output Current 1 Source’s output current in 50mA units. When set to 0xFF, the Source does not support this field. 3 Real Time Flags Bit Description 0 Reserved and Shall be set to zero 1...2 PTF  PTF: 00 – Not Supported  PTF: 01 – Normal  PTF: 10 – Warning  PTF: 11 – Over temperature 3 OMF OMF (Operating Mode Flag) is set when operating in Current Limit mode and cleared when operating in Constant Voltage mode. 4...7 Reserved and Shall be set to zero Extended Header Data Size = 4 PPSSDB (4-byte Data Block) Page 236 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.10.3 Real Time Flags Field Real Time flags provide a real-time indication of the Source's operating state:  The PTF (Present Temperature Flag) Shall provide a real-time indication of the Source's internal thermal status. If the PTF is not supported, it will be set to zero:  Normal indicates that the Source is operating within its normal thermal envelope.  Warning indicates that the Source is over-heating but is not in imminent danger of shutting down.  Over Temperature indicates that the Source is over heated and will shut down soon or has already shutdown and has sent the OTP Event flag in an Alert Message.  The OMF (Operating Mode Flag) Shall provide a real-time indication of the SPR PPS Source's operating mode. When set, the Source is operating in Current Limit mode; when cleared it is operating Constant Voltage mode. This bit Shall be set to zero when not in SPR PPS Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 237 6.5.11 Country_Codes Message The Country_Codes Message Shall be sent in response to a Get_Country_Codes Message. The Country_Codes Message enables a Port to query its Port Partner to get a list of alpha-2 country codes as defined in [ISO 3166] for which the Port Partner has country specific information. The Country_Codes Message Shall contain a 4…26-byte Country Code Data Block (CCDB) whose format Shall be as shown in Figure 6.50, "Country_Codes Message" and Table 6.63, "Country Codes Data Block (CCDB)". Figure 6.50 Country_Codes Message 6.5.11.1 Country Code Field The Country Code field Shall contain Length Country Codes in the Alpha-2 Country Code defined by [ISO 3166]. Table 6.63 Country Codes Data Block (CCDB) Offset Field Description 0 Length Number of country codes in the Message 1 Reserved Shall be set to zero. 2... Length * 2n Country Code Offset Field Description 2 1st Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 3 Second character of the Alpha-2 Country Code defined by [ISO 3166] 4 2nd Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 5 Second character of the Alpha-2 Country Code defined by [ISO 3166] … Length * 2n nth Country Code Extended Header Data Size = 4-26 CCDB (4-26 byte Data Block) Page 238 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.12 Country_Info Message The Country_Info Message Shall be sent in response to a Get_Country_Info Message. The Country_Info Message enables a Port to get additional country specific information from its Port Partner. The Country_Info Message Shall contain a 4…26-byte Country Info Data Block (CIDB) whose format Shall be as shown in Figure 6.51, "Country_Info Message" and Table 6.64, "Country Info Data Block (CIDB)". Figure 6.51 Country_Info Message 6.5.12.1 Country Code Field The Country Code field Shall contain the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 6.5.12.2 Country Specific Data Field The Country Specific Data field Shall contain content defined by and formatted in a manner determined by an official agency of the country indicated in the Country Code field. If the Country Code field in the Get_Country_Info Message is unrecognized then Country Specific Data field Shall return the null terminated ASCII text string "Unsupported Code". Table 6.64 Country Info Data Block (CIDB) Offset Field Size 0 Country Code First character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 1 Second character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message 2…3 Reserved Shall be set to zero. 4 Country Specific Data 1…22 bytes of content defined by the country’s authority. Extended Header Data Size = 4-26 CIDB (4-26 byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 239 6.5.13 Sink_Capabilities_Extended Message The Sink_Capabilities_Extended Message Shall be sent in response to a Get_Sink_Cap_Extended Message. The Sink_Capabilities_Extended Message enables a Sink or a DRP to inform the Source about its Capabilities as a Sink. The Sink_Capabilities_Extended Message Shall return a 24-byte Sink Capabilities Extended Data Block (SKEDB) whose format Shall be as shown in Figure 6.52, "Sink_Capabilities_Extended Message" and Table 6.65, "Sink Capabilities Extended Data Block (SKEDB)". Figure 6.52 Sink_Capabilities_Extended Message Table 6.65 Sink Capabilities Extended Data Block (SKEDB) Offset (Byte) Field Size (Bytes) Type Description 0 VID 2 Numeric Vendor ID (assigned by the USB-IF) 2 PID 2 Numeric Product ID (assigned by the manufacturer) 4 XID 4 Numeric Value provided by the USB-IF assigned to the product 8 FW Version 1 Numeric Firmware version number 9 HW Version 1 Numeric Hardware version number 10 SKEDB Version 1 Numeric SKEDB Version (not the specification Version):  Version 1.0 = 1 Values 0 and 2-255 are Reserved and Shall Not be used. 11 Load Step 1 Bit Field Bit Description 0...1  00b: 150mA/μs Load Step (default)  01b: 500mA/μs Load Step 11b…10b: Reserved and Shall Not be used. 2...7 Reserved and Shall be set to zero 12 Sink Load Characteristics 2 Bit Field Bit Description 0...4 Percent overload in 10% increments. Values higher than 25 (11001b) are clipped to 250%. 00000b is the default. 5...10 Overload period in 20ms when bits 0...4 non-zero. 1...14 Duty cycle in 5% increments when bits 0...4 are non-zero. 15 Can tolerate VBUS voltage droop 14 Compliance 1 Bit Field Bit Description 0 Requires LPS Source when set 1 Requires PS1 Source when set 2 Requires PS2 Source when set 3...7 Reserved and Shall be set to zero Extended Header Data Size = 24 SKEDB (24 byte Data Block) Page 240 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Sink's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.13.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Sink's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 15 Touch Temp 1 Value Temperature conforms to:  0 = Not applicable  1 = [IEC 60950-1] (default)  2 = [IEC 62368-1] TS1  3 = [IEC 62368-1] TS2 Note: All other values Reserved 16 Battery Info 1 Byte Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 17 Sink Modes 1 Bit Field Bit Description 0 PPS charging supported 1 VBUS powered 2 AC Supply powered 3 Battery powered 4 Battery essentially unlimited 5 AVS Support 6...7 Reserved and Shall be set to zero 18 SPR Sink Minimum PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 7 Reserved and Shall be set to zero 19 SPR Sink Operational PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its normal functionality. 7 Reserved and Shall be set to zero 20 SPR Sink Maximum PDP 1 Byte Bit Description 0...6 The maximum PDP the Sink will ever request. 7 Reserved and Shall be set to zero 21 EPR Sink Minimum PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 22 EPR Sink Operational PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its normal functionality. 23 EPR Sink Maximum PDP 1 Byte The maximum PDP that the EPR Sink will ever request. Table 6.65 Sink Capabilities Extended Data Block (SKEDB) (Continued) Offset (Byte) Field Size (Bytes) Type Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 241 6.5.13.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.13.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.13.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.13.6 SKEDB Version Field The SKEDB Version field contains the version level of the SKEDB. Currently only Version 1 is defined. 6.5.13.7 Load Step Field The Load Step field contains bits indicating the Load Step Slew Rate and Magnitude that this Sink prefers. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.13.8 Sink Load Characteristics Field The Sink Shall report its preferred load characteristics in the Sink Load Characteristics field. Regardless of this value, in operation its load Shall Not exceed the Capabilities reported in the Source_Capabilities_Extended Message. 6.5.13.9 Compliance Field The Compliance field Shall contain the types of Sources the Sink has been tested and certified with (see Section 7.1.12.3, "Compliance Field"). 6.5.13.10 Touch Temp The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Sink's enclosure. Safety limits for the Sink's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Sink May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.13.11 Battery Info The Battery Info field Shall report the number of Fixed Batteries and Hot Swappable Battery slots the Sink supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. The information reported in the Battery Info field Shall match that reported in the Number of Batteries/Battery Slots field of the Source_Capabilities_Extended Message. A Sink Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 242 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.12 Sink Modes The Sink Modes bit field Shall identify the charging Capabilities and the power sources that can be used by the Sink. When bit 0 is set, the Sink has the ability to use a PPS Source for fast charging. The source of power a Sink can use:  When bit 1 is set, the Sink has the ability to be sourced by VBUS.  When bit 2 is set, the Sink has the ability to be sourced by an AC Supply.  When bit 3 is set, the Sink has the ability to be sourced by a Battery.  When bit 4 is set, the Sink has the ability to be sourced by a Battery with essentially infinite energy (e.g., a car battery). Bits 1-4 May be set independently of one another. The combination indicates what sources of power the Sink can utilize. For example, some Sinks are only powered by a Battery (e.g., an automobile battery) rather than the more common AC Supply and some Sinks are only powered from VBUS or VCONN. When bit 5 is set, the Sink has the ability to support AVS. 6.5.13.13 SPR Sink Minimum PDP The SPR Sink Minimum PDP field Shall contain the minimum power Source PDP needed by the Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The SPR Sink Minimum PDP field Shall be less than or equal to the SPR Sink Operational PDP. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of SPR Sink Minimum PDP could be:  The minimum power a wireless Charger would require in order to detect, and deliver the minimum required amount of power to the attached device.  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device 6.5.13.14 SPR Sink Operational PDP The SPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The SPR Sink Operational PDP field Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), the SPR Sink Operational PDP field Shall correspond to the PDP Rating of the Charger shipped with the Sink or the recommended Charger's PDP Rating. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set the SPR Sink Minimum PDP field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 243 6.5.13.15 SPR Sink Maximum PDP The SPR Sink Maximum PDP field Shall contain the highest PDP the Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The SPR Sink Maximum PDP field Shall Not be less than the SPR Sink Operational PDP field, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. 6.5.13.16 EPR Sink Minimum PDP The EPR Sink Minimum PDP field Shall contain the Source PDP needed by an EPR Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery, if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The EPR Sink Minimum PDP field Shall be less than or equal to the EPR Sink Operational PDP field value. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of EPR Sink Minimum PDP could be:  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device. Note: EPR Sink Minimum PDP can be the same as its SPR Sink Minimum PDP. 6.5.13.17 EPR Sink Operational PDP The EPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of EPR Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The EPR Sink Operational PDP Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), it Shall correspond to the PDP Rating of the Charger shipped with the EPR Sink or the recommended Charger's PDP Rating. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. 6.5.13.18 EPR Sink Maximum PDP The EPR Sink Maximum PDP field Shall be highest PDP the EPR Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The EPR Sink Maximum PDP field Shall Not be less than the EPR Sink Operational PDP, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. Page 244 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.14 Extended_Control Message The Extended_Control Message extends the Control Message space. The Extended_Control Message includes one byte of data. The Extended_Control Message Shall be as shown in Figure 6.53, "Extended_Control Message" and Table 6.66, "Extended Control Data Block (ECDB)". Figure 6.53 Extended_Control Message The Extended_Control Message types are specified in the Type field of the ECDB and are listed in Table 6.67, "Extended Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets. 6.5.14.1 EPR_Get_Source_Cap Message The EPR_Get_Source_Cap (EPR Get Source Capabilities) Message Shall only be sent by a Port capable of operating as a Sink and that supports EPR Mode to request the Source Capabilities and Dual-Role Power capability of its Port Partner. A Port that can operate as an EPR Source Shall respond by returning an EPR_Source_Capabilities Message (see Section 6.5.15.2, "EPR_Source_Capabilities Message"). A Port that does not support EPR Mode as a Source Shall return the Not_Supported Message. An EPR Capable Sink Port that is operating in SPR Mode Shall treat the EPR_Source_Capabilities Message as informational only and Shall Not respond with an EPR_Request Message. 6.5.14.2 EPR_Get_Sink_Cap Message The EPR_Get_Sink_Cap (EPR Get Sink Capabilities) Message Shall only be sent by a Port capable of operating as a Source and that supports EPR Mode to request the Sink Capabilities and Dual-Role Power capability of its Port Partner. A Port that is EPR Capable operating as a Sink Shall respond by returning an EPR_Sink_Capabilities Message (see Section 6.5.15.3, "EPR_Sink_Capabilities Message"). A Port that does not support EPR Mode as a Sink Shall return the Not_Supported Message. Table 6.66 Extended Control Data Block (ECDB) Offset Field Value Description 0 Type Unsigned Int Extended Control Message Type 1 Data Byte Shall be set to zero when not used. Table 6.67 Extended Control Message Types Type Data Message Type Sent by Description Valid Start of Packet 0 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 Not used EPR_Get_Source_Cap Sink or DRP See Section 6.5.14.1 SOP only 2 Not used EPR_Get_Sink_Cap Source or DRP See Section 6.5.14.2 SOP only 3 Not used EPR_KeepAlive Sink See Section 6.5.14.3 SOP only 4 Not Used EPR_KeepAlive_Ack Source See Section 6.5.14.4 SOP only 5...255 Reserved All values not explicitly defined are Reserved and Shall Not be used. Extended Header Data Size = 2 ECDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 245 6.5.14.3 EPR_KeepAlive Message The EPR_KeepAlive Message May be sent by a Sink operating in EPR Mode to meet the requirement for periodic traffic. The Source operating on EPR Mode responds by returning an EPR_KeepAlive_Ack Message to the Sink. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.14.4 EPR_KeepAlive_Ack Message The EPR_KeepAlive_Ack Message Shall be sent by a Source operating in EPR Mode in response to an EPR_KeepAlive Message. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.15 EPR Capabilities Message The EPR Capabilities Message is an Extended Capabilities Message made of Power Data Objects (PDO) defined in Section 6.4.1, "Capabilities Message". It is used to form EPR_Source_Capabilities Messages and EPR_Sink_Capabilities Messages. Sources expose their EPR power Capabilities by sending an EPR_Source_Capabilities Message. Sinks expose their EPR power requirements by returning an EPR_Sink_Capabilities Message when requested. Both are composed of a number of 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). An EPR Capabilities Message Shall have a 5V Fixed Supply PDO containing the sending Port's information in the first object position followed by up to 10 additional PDOs. 6.5.15.1 EPR Capabilities Message Construction The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. See Figure 6.54, "Mapping SPR Capabilities to EPR Capabilities". Figure 6.54 Mapping SPR Capabilities to EPR Capabilities Power Data Objects in the EPR Capabilities Messages Shall be sent in the following order: 1) The SPR (A)PDOs as reported in the SPR Capabilities Message. The Number of Data Objects field in the Message Header of the EPR Capabilities Message is the same as the Number of Data Objects field in the Message Header of the SPR Capabilities Message. 2) If the SPR Capabilities Message contains fewer than 7 PDOs, the unused Data Objects Shall be zero filled. 3) The EPR (A)PDOs as defined in Section 6.4.1, "Capabilities Message" Shall start at Data Object position 8 and Shall be sent in the following order: a) Fixed Supply PDOs that offer 28V, 36V or 48V, if present, Shall be sent in voltage order; lowest to highest. b) One EPR AVS APDO Shall be sent. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 EPR PDO 8 EPR PDO 9 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 PDOs > 20V2 001b 010b 011b 100b 101b 110b 111b 1000b 1001b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b EPR PDO 10 EPR PDO 11 1010b 1011b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. 2) See Section 10 “Power Rules” for rules, on which EPR (A)PDOs are allowed be used for a given PDP. Page 246 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.15.2 EPR_Source_Capabilities Message The EPR_Source_Capabilities is an EPR Capabilities Message containing a list of Power Data Objects that the EPR Source is capable of supplying. It is sent by an EPR Source in order to convey its Capabilities to a Sink. An EPR Source Shall send the EPR_Source_Capabilities Message:  When entering EPR Mode  While in EPR Modes when its Capabilities change  In response to an EPR_Get_Source_Cap Message  After a Soft Reset while in EPR Mode An EPR Sink operating in EPR Mode Shall evaluate every EPR_Source_Capabilities Message it receives and Shall respond with a EPR_Request Message. If its power consumption exceeds the Source Capabilities, it Shall Re- negotiate so as not to exceed the Source's most recently Advertised Source Capabilities. While operating in SPR Mode, an EPR Sink receiving an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Messages Shall Not respond with an EPR_Request Message. The (A)PDOs in an EPR_Source_Capabilities Message Shall only be requested using the EPR_Request Message and only when in EPR Mode. When Source wants to exit EPR Mode, if not already in power contract with an SPR (A)PDO, it Shall send an EPR_Source_Capabilities Message with no EPR (A)PDOs (i.e. seven SPR (A)PDOs including any zero padded ones). See Figure 6.55, "EPR_Source_Capabilities message with no EPR PDOs". Figure 6.55 EPR_Source_Capabilities message with no EPR PDOs 6.5.15.3 EPR_Sink_Capabilities Message The EPR_Sink_Capabilities is an EPR Capabilities Message that contains a list of Power Data Objects that the EPR Sink requires to operate. It is sent by an EPR Sink in order to convey its power requirements to an EPR Source. The EPR Sink Shall only send the EPR_Sink_Capabilities Message in response to an EPR_Get_Sink_Cap Message. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 001b 010b 011b 100b 101b 110b 111b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 247 6.5.16 Vendor_Defined_Extended Message The Vendor_Defined_Extended Message (VDEM) is provided to allow vendors to exchange information outside of that defined by this specification using the Extended Message format. A Vendor_Defined_Extended Message Shall consist of at least one Vendor Data Object, the VDM Header, and May contain up to a maximum of 256 additional data bytes. To ensure vendor uniqueness of Vendor_Defined_Extended Messages, all Vendor_Defined_Extended Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. A VDEM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined_Extended Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. For example, a Vendor_Defined_Extended Message could be used to enable the Source to offer additional power via a Source_Capabilities Message. Vendor_Defined_Extended Messages Shall Not be used where equivalent functionality is contained in the PD Specification e.g., authentication or firmware update. The Message format Shall be as shown in Figure 6.56, "Vendor_Defined_Extended Message". Figure 6.56 Vendor_Defined_Extended Message The VDM Header Shall be the first 4-bytes in a Vendor Defined Extended Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. The VDM Header in the VDEM Shall follow the Unstructured VDM Header format as defined in Section 6.4.4.1, "Unstructured VDM". VDEMs Shall only be sent and received after an Explicit Contract has been established. A VDEM AMS Shall Not interrupt any other PD AMS. The VDEM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the SVID. The Port Partners and Cable Plugs Shall exit any states entered using a VDEM according to the rules defined in Section 6.4.4.3.4, "Enter Mode Command". The following rules apply to the use of VDEM Messages:  VDEMs Shall Not be initiated or responded to under any other circumstances than the following:  VDEMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract VDEMs Shall Not be sent and Shall be Ignored if received.  Cable Plugs Shall Not initiate VDEMs. Extended Header Data Size = 4...260 VDM Header VDEDB (0...256-byte Data Block) Page 248 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  VDEMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can VDEMs be sent or received. The Active Mode and the associated VDEMs Shall use the same SVID.  VDEMs May be used with SOP* Packets.  When a DFP or UFP does not support VDEMs or does not recognize the VID it Shall return a Not_Supported Message. Note: Usage of VDEMs with Chunking is not recommended since this is less efficient than using Unstructured VDMs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 249 6.6 Timers All the following timers are defined in terms of bits on the bus regardless of where they are implemented in terms of the logical architecture. This is to ensure a fixed reference for the starting and stopping of timers. It is left to the implementer to ensure that this timing is observed in a real system. 6.6.1 CRCReceiveTimer The CRCReceiveTimer Shall be used by the sender's Protocol Layer to ensure that a Message has not been lost. Failure to receive an acknowledgment of a Message (a GoodCRC Message) whether caused by a bad GoodCRC Message on the receiving end or by a garbled Message within tReceive is detected when the CRCReceiveTimer expires. The sender's Protocol Layer response when a CRCReceiveTimer expires Shall be to retry nRetryCount times. Note: Cable Plugs do not retry Messages and large Extended Messages that are not Chunked are not retried (see Section 6.7.2, "Retry Counter"). Sending of the Preamble corresponding to the retried Message Shall start within tRetry of the CRCReceiveTimer expiring. The CRCReceiveTimer Shall be started when the last bit of the Message EOP has been transmitted by the PHY Layer. The CRCReceiveTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer. The Protocol Layer receiving a Message Shall respond with a GoodCRC Message within tTransmit in order to ensure that the sender's CRCReceiveTimer does not expire. The tTransmit time Shall be measured from when the last bit of the Message EOP has been received by the PHY Layer until the first bit of the Preamble of the GoodCRC Message has been transmitted by the PHY Layer. 6.6.2 SenderResponseTimer The SenderResponseTimer Shall be used by the sender's Policy Engine to ensure that a Message requesting a response (e.g., Get_Source_Cap Message) is responded to within a bounded time of tSenderResponse. Failure to receive the expected response is detected when the SenderResponseTimer expires. For Extended Messages received as Chunks, the SenderResponseTimer will also be started and stopped by the Chunking Rx State Machine. See Section 8.3.3.1.1, "SenderResponseTimer State Diagram" for more details of the SenderResponseTimer operation. The Policy Engine's response when the SenderResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The SenderResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the Message requesting a response, has been received by the PHY Layer. The SenderResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected response Message, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tReceiverResponse in order to ensure that the sender's SenderResponseTimer does not expire. The tReceiverResponse time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the expected request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.3 Capability Timers Sources and Sinks use Capability Timers to determine Attachment of a PD Capable device. By periodically sending or requesting Capabilities, it is possible to determine PD device Attachment when a response is received. Page 250 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.3.1 SourceCapabilityTimer Prior to the First Explicit Contract a Source Shall use the SourceCapabilityTimer to periodically send out a Source_Capabilities Message every tTypeCSendSourceCap while:  The Port is Attached.  The Source is not in an active connection with a PD Sink Port. Whenever there is a SourceCapabilityTimer timeout the Source Shall send a Source_Capabilities Message. It Shall then re-initialize and restart the SourceCapabilityTimer. The SourceCapabilityTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer since a PD connection has been established. At this point, the Source waits for a Request Message or a response timeout. Note: The Source can also stop sending Source_Capabilities Message after nCapsCount Messages have been sent without a GoodCRC Message response (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.2, "Policy Engine Source Port State Diagram" for more details of when Source_Capabilities Messages are transmitted. 6.6.3.2 SinkWaitCapTimer The Sink Shall support the SinkWaitCapTimer. While in a Default Contract or an Implicit Contract when a Sink observes an absence of Source_Capabilities Messages, after VBUS is present, for a duration of tTypeCSinkWaitCap the Sink May issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter") or continue to operate at USB Type-C current. When a Sink, entering EPR Mode, observes an absence of EPR_Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to exit EPR Mode (see Section 6.4.10, "EPR_Mode Message"). When a Sink, exiting EPR Mode, observes an absence of Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.3, "Policy Engine Sink Port State Diagram" for more details of when the SinkWaitCapTimer is run. 6.6.3.3 tFirstSourceCap After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap a Source Shall send its first Source_Capabilities Message within tFirstSourceCap of VBUS reaching vSafe5V. After Soft Reset, a Source Shall send its first Source Capabilities Message within tFirstSourceCap after last bit of the GoodCRC Message EOP corresponding to Accept Message. This ensures that the Sink receives a Source Capabilities Message before the Sink's SinkWaitCapTimer expires. A Source entering EPR Mode Shall send its first EPR_Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded). A Source exiting EPR Mode Shall send its first Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 251 6.6.4 Wait Timers and Times 6.6.4.1 SinkRequestTimer The SinkRequestTimer is used to ensure that the time before the next Sink Request Message, after a Wait Message has been received from the Source in response to a Sink Request Message, is a minimum of tSinkRequest min (see Section 6.3.12, "Wait Message"). The SinkRequestTimer Shall be started when the EOP of a Wait Message has been received and Shall be stopped if any other Message is received or during a Hard Reset. The Sink Shall wait at least tSinkRequest, after receiving the EOP of a Wait Message sent in response to a Sink Request Message, before sending a new Request Message. Whenever there is a SinkRequestTimer timeout the Sink May send a Request Message. It Shall then re-initialize and restart the SinkRequestTimer. 6.6.4.2 tPRSwapWait The time before the next PR_Swap Message, after a Wait Message has been received in response to a PR_Swap Message is a minimum of tPRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tPRSwapWait after receiving the EOP of a Wait Message sent in response to a PR_Swap Message, before sending a new PR_Swap Message. 6.6.4.3 tDRSwapWait The time before the next DR_Swap Message, after a Wait Message has been received in response to a DR_Swap Message is a minimum of tDRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tDRSwapWait after receiving the EOP of a Wait Message sent in response to a DR_Swap Message, before sending a new DR_Swap Message. 6.6.4.4 tVCONNSwapWait The time before the next VCONN_Swap Message, after a Wait Message has been received in response to a VCONN_Swap Message is a minimum of tVCONNSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tVCONNSwapWait after receiving the EOP of a Wait Message sent in response to a VCONN_Swap Message, before sending a new VCONN_Swap Message. 6.6.4.5 tVCONNSwapDelayDFP The time delay for DFP after losing VCONN Source role due to an incoming VCONN Swap request from UFP and before sending the next VCONN_Swap Message. The DFP Shall wait at least tVCONNSwapDelayDFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.6 tVCONNSwapDelayUFP The time delay for UFP after losing VCONN Source role due to an incoming VCONN Swap request from DFP and before sending the next VCONN_Swap Message. The UFP Shall wait at least tVCONNSwapDelayUFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.7 tEnterUSBWait The time before the next Enter_USB Message, after a Wait Message has been received in response to a Enter_USB Message is a minimum of tEnterUSBWait min (see Section 6.3.12, "Wait Message"). The DFP Shall wait at least tEnterUSBWait after receiving the EOP of a Wait Message sent in response to an Enter_USB Message, before sending a new Enter_USB Message. 6.6.5 Power Supply Timers See Section 7.3, "Transitions" for diagrams showing the usage of the timers in this section. Page 252 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.5.1 PSTransitionTimer The PSTransitionTimer is used by the Policy Engine to timeout on a PS_RDY Message. It is started when a request for new Source Capabilities has been accepted and will timeout after tPSTransition if a PS_RDY Message has not been received. This condition leads to a Hard Reset and a return to USB Default Operation. The PSTransitionTimer relates to the time taken for the Source to transition from one voltage, or current level, to another (see Section 7.1, "Source Requirements"). The PSTransitionTimer Shall be started when the last bit of the GoodCRC Message EOP, corresponding to an Accept Message, has been transmitted by the PHY Layer. The PSTransitionTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer. 6.6.5.2 PSSourceOffTimer 6.6.5.2.1 Use during Power Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is currently acting as a Sink to timeout on a PS_RDY Message during a Power Role Swap AMS. This condition leads to USB Type-C Error Recovery. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Source the Sink can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this transmitted Accept Message, is received by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Sink the Source can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this received Accept Message, is transmitted by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the remote Dual-Role Power Device to stop supplying power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the remote Dual-Role Power Device within tPSSourceOff indicating this has occurred. 6.6.5.2.2 Use during Fast Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is the Initial Sink (currently providing vSafe5V) to timeout on a PS_RDY Message during a Fast Role Swap AMS. This condition leads to USB Type-C Error Recovery. When the FR_Swap Message request has been sent by the Initial Sink, the Initial Source Shall respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this Accept Message is received by the Initial Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the Initial Source to stop supplying power and for VBUS to revert to vSafe5V (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the Initial Source within tPSSourceOff indicating this has occurred. 6.6.5.3 PSSourceOnTimer 6.6.5.3.1 Use during Power Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Power Role Swap. This condition leads to USB Type-C Error Recovery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 253 The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer.  The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.5.3.2 Use during Fast Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Fast Role Swap. This condition leads to USB Type-C Error Recovery. The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer. The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.6 NoResponseTimer The NoResponseTimer is used by the Policy Engine in a Source to determine that its Port Partner is not responding after a Hard Reset. When the NoResponseTimer times out, the Policy Engine Shall issue up to nHardResetCount additional Hard Resets before determining that the Port Partner is non-responsive to USB Power Delivery messaging. If the Source fails to receive a GoodCRC Message in response to a Source_Capabilities Message within tNoResponse of:  The last bit of a Hard Reset Signaling being sent by the PHY Layer if the Hard Reset Signaling was initi- ated by the Sink.  The last bit of a Hard Reset Signaling being received by the PHY Layer if the Hard Reset Signaling was initiated by the Source. Then the Source Shall issue additional Hard Resets up to nHardResetCount times (see Section 6.8.3, "Hard Reset"). For a non-responsive device, the Policy Engine in a Source May either decide to continue sending Source_Capabilities Messages or to go to non-USB Power Delivery operation and cease sending Source_Capabilities Messages. 6.6.7 BIST Timers 6.6.7.1 tBISTCarrierMode tBISTCarrierMode is used to define the maximum time that a UUT has to enter BIST Carrier Mode when requested by a Tester. Page 254 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A UUT Shall enter BIST Carrier Mode within tBISTCarrierMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. In BIST Carrier Mode when transmitting a continuous carrier signal transmission Shall start as soon as the UUT enters BIST Mode. 6.6.7.2 BISTContModeTimer The BISTContModeTimer is used by a UUT to ensure that a Continuous BIST Mode (i.e., BIST Carrier Mode) is exited in a timely fashion. A UUT that has been put into a Continuous BIST Mode Shall return to normal operation (either PE_SRC_Transition_to_default, PE_SNK_Transition_to_default, or PE_CBL_Ready) within tBISTContMode of starting to transmit a continuous carrier signal. 6.6.7.3 tBISTSharedTestMode tBISTSharedTestMode is used to define the maximum time that a UUT has to enter BIST Shared Capacity Test Mode when requested by a Tester. A UUT Shall enter BIST Shared Capacity Test Mode and send a new Source_Capabilities Message from all Ports within the Shared Capacity Group within tBISTSharedTestMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. 6.6.8 Power Role Swap Timers 6.6.8.1 SwapSourceStartTimer The SwapSourceStartTimer Shall be used by the New Source, after a Power Role Swap or Fast Role Swap, to ensure that it does not send Source_Capabilities Message before the New Sink is ready to receive the Source_Capabilities Message. The New Source Shall Not send the Source_Capabilities Message earlier than tSwapSourceStart after the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. The Sink Shall be ready to receive a Source_Capabilities Message tSwapSinkReady after having sent the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. 6.6.9 Soft Reset Timers 6.6.9.1 tSoftReset A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure. This Shall cause the Source or Sink to send a Soft_Reset Message, transmission of which Shall be completed within tSoftReset of the CRCReceiveTimer expiring. 6.6.9.2 tProtErrSoftReset If the Protocol Error occurs that causes the Source or Sink to send a Soft_Reset Message, the transmission of the Soft_Reset Message Shall be completed within tProtErrSoftReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.10 Data Reset Timers 6.6.10.1 VCONNDischargeTimer The VCONNDischargeTimer is used by the Policy Engine in the DFP to ensure the UFP actively discharges VCONN in a timely manner to ensure the cable will restore Ra. Once the UFP has discharged VCONN below vRaReconnect (see [USB Type-C 2.4]) it sends a PS_RDY Message (see also Section 7.1.15, "VCONN Power Cycle"). If the DFP does not receive a PS_RDY Message from the UFP within tVCONNSourceDischarge of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message, the VCONNDischargeTimer will time out and the Policy Engine Shall enter the ErrorRecovery State. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 255 6.6.10.2 tDataReset The DFP Shall complete the Data_Reset process (as defined in Section 6.3.14, "Data_Reset Message") within tDataReset of the last bit of the GoodCRC Message EOP, corresponding to the Accept Message, being transmitted by the PHY Layer. 6.6.10.3 DataResetFailTimer The DataResetFailTimer Shall be used by the DFP's Policy Engine to ensure the Data Reset process completes within tDataResetFail of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the DFP's DataResetFailTimer expires, the DFP Shall enter the ErrorRecovery State. 6.6.10.4 DataResetFailUFPTimer The DataResetFailUFPTimer Shall be used by the UFP's Policy Engine to ensure the Data Reset process completes within tDataResetFailUFP of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the UFP's DataResetFailUFPTimer expires, the UFP Shall enter the ErrorRecovery State. 6.6.11 Hard Reset Timers 6.6.11.1 HardResetCompleteTimer The HardResetCompleteTimer is used by the Protocol Layer in the case where it has asked the PHY Layer to send Hard Reset Signaling and the PHY Layer is unable to send the Signaling within a reasonable time due to a non-Idle channel. If the PHY Layer does not indicate that the Hard Reset Signaling has been sent within tHardResetComplete of the Protocol Layer requesting transmission, then the Protocol Layer Shall inform the Policy Engine that the Hard Reset Signaling has been sent in order to ensure the power supply is reset in a timely fashion. 6.6.11.2 PSHardResetTimer The PSHardResetTimer is used by the Policy Engine in a Source to ensure that the Sink has had sufficient time to process Hard Reset Signaling before turning off its power supply to VBUS. When a Hard Reset occurs the Source, stops driving VCONN, removes Rp from the CC pin and starts to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. See Section 7.1.5, "Response to Hard Resets". 6.6.11.3 tDRSwapHardReset If a DR_Swap Message is received during Modal Operation then a Hard Reset Shall be initiated by the recipient of the unexpected DR_Swap Message; Hard Reset Signaling Shall be generated within tDRSwapHardReset of the EOP of the GoodCRC sent in response to the DR_Swap Message. 6.6.11.4 tProtErrHardReset If a Protocol Error occurs that directly leads to a Hard Reset, the transmission of the Hard Reset Signaling Shall be completed within tProtErrHardReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.12 Structured VDM Timers 6.6.12.1 VDMResponseTimer The VDMResponseTimer Shall be used by the Initiator's Policy Engine to ensure that a Structured VDM Command request needing a response (e.g. Discover Identity Command request) is responded to within a bounded time of tVDMSenderResponse. The VDMResponseTimer Shall be applied to all Structured VDM Commands except the Page 256 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Enter Mode and Exit Mode Commands which have their own timers (VDMModeEntryTimer and VDMModeExitTimer respectively). Failure to receive the expected response is detected when the VDMResponseTimer expires. The Policy Engine's response when the VDMResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The VDMResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected VDM Command response, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMReceiverResponse in order to ensure that the sender's VDMResponseTimer does not expire. The tVDMReceiverResponse time Shall be measured from the time the last bit of the Message EOP has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.2 VDMModeEntryTimer The VDMModeEntryTimer Shall be used by the Initiator's Policy Engine to ensure that the response to a Structured VDM Enter Mode Command request (ACK or NAK with ACK indicating that the requested Alternate Mode has been entered) arrives within a bounded time of tVDMWaitModeEntry. Failure to receive the expected response is detected when the VDMModeEntryTimer expires. The Policy Engine's response when the VDMModeEntryTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.1, "DFP Structured VDM Mode Entry State Diagram"). The VDMModeEntryTimer Shall be started from the time the last bit of the EOP of the GoodCRC Message, corresponding to the VDM Command request, has been received by the PHY Layer. The VDMModeEntryTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected Structured VDM Command response (ACK, NAK or BUSY), has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMEnterMode in order to ensure that the sender's VDMModeEntryTimer does not expire. The tVDMEnterMode time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to VDM Command Request, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.3 VDMModeExitTimer The VDMModeExitTimer Shall be used by the Initiator's Policy Engine to ensure that the ACK response to a Structured VDM Exit Mode Command, indicating that the requested Alternate Mode has been exited, arrives within a bounded time of tVDMWaitModeExit. Failure to receive the expected response is detected when the VDMModeExitTimer expires. The Policy Engine's response when the VDMModeExitTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.2, "DFP Structured VDM Mode Exit State Diagram"). The VDMModeExitTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMModeExitTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the expected Structured VDM Command response ACK, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMExitMode in order to ensure that the sender's VDMModeExitTimer does not expire. The tVDMExitMode time Shall be measured from the time the last bit of the Message EOP has been received by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 257 6.6.12.4 tVDMBusy The Initiator Shall wait at least tVDMBusy, after receiving a BUSY Command response, before repeating the Structured VDM request again. 6.6.13 VCONN Timers 6.6.13.1 VCONNOnTimer The VCONNOnTimer is used during a VCONN Swap. The VCONNOnTimer Shall be started when:  The last bit of GoodCRC Message EOP, corresponding to the Accept Message, is transmitted or received by the PHY Layer. The VCONNOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, is transmitted by the PHY Layer. Prior to sending the PS_RDY Message, the Port Shall have turned VCONN On. 6.6.13.2 tVCONNSourceOff The tVCONNSourceOff time applies during a VCONN Swap. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, being transmitted by the PHY Layer. 6.6.14 tCableMessage Ports compliant with Revision 3.x of the specification Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet even when communicating using [USBPD 2.0] with a Cable Plug. This specification defines Collision Avoidance mechanisms that obviate the need for this time. Cable Plugs Shall only wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet when operating at [USBPD 2.0]. When operating at Revisions higher than [USBPD 2.0] Cable Plugs Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet. 6.6.15 DiscoverIdentityTimer The DiscoverIdentityTimer is used prior to or during an Explicit Contract when discovering whether a Cable Plug is PD Capable using SOP’. When performing Cable Discovery during an Explicit Contract the Discover Identity Command request Shall be sent every tDiscoverIdentity. No more than nDiscoverIdentityCount Discover Identity Messages without a GoodCRC Message response Shall be sent. If no GoodCRC Message response is received after nDiscoverIdentityCount Discover Identity Command requests have been sent by a Port, the Port Shall Not send any further SOP’/SOP’’ Messages. 6.6.16 Collision Avoidance Timers 6.6.16.1 SinkTxTimer The SinkTxTimer is used by the Protocol Layer in a Source to allow the Sink to complete its transmission before initiating an AMS. The Source Shall wait a minimum of tSinkTx after changing Rp from SinkTxOK to SinkTxNG before initiating an AMS by sending a Message. A Sink Shall only initiate an AMS when it has determined that Rp is set to SinkTxOK. Page 258 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.16.2 tSrcHoldsBus If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. 6.6.17 Fast Role Swap Timers 6.6.17.1 tFRSwap5V The tFRSwap5V time Shall be measured from:  The later of:  The last bit of the GoodCRC Message EOP, corresponding to the Accept Message or  VBUS being within vSafe5V.  Until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. During a Fast Role Swap, the Initial Source Shall start the PS_RDY Message within tFRSwap5V after both:  The Initial Source has sent the Accept Message, and  VBUS is at or below vSafe5V. 6.6.17.2 tFRSwapComplete During a fast-role swap, the Initial Sink Shall respond with a the PS_RDY Message within tFRSwapComplete after it has received the PS_RDY Message from the Initial Source. The tFRSwapComplete time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. 6.6.17.3 tFRSwapInit That last bit of the EOP of the FR_Swap Message Shall be transmitted by the New Source no later than tFRSwapInit after the Fast Role Swap Request has been detected (see Section 5.8.6.3, "Fast Role Swap Detection"). 6.6.18 Chunking Timers 6.6.18.1 ChunkingNotSupportedTimer The ChunkingNotSupportedTimer is used by a Source or Sink which does not support multi-chunk Chunking but has received a Message Chunk. The ChunkingNotSupportedTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to a Message Chunk of a multi-chunk Message, is transmitted by the PHY Layer. The Policy Engine Shall Not send its Not_Supported Message before the ChunkingNotSupportedTimer expires. 6.6.18.2 ChunkSenderRequestTimer The ChunkSenderRequestTimer is used during a Chunked Message transmission. The ChunkSenderRequestTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Response is responded to within a bounded time of tChunkSenderRequest. Failure to receive the expected response is detected when the ChunkSenderRequestTimer expires. The ChunkSenderRequestTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is received by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 259 The ChunkSenderRequestTimer Shall be stopped when:  The last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, is trans- mitted by the PHY Layer.  A Message other than a Chunk Request is received from the Protocol Layer Rx. The receiver of a Chunk Response requiring a Chunk Request Shall respond with a Chunk Request within tChunkReceiverRequest in order to ensure that the sender's ChunkSenderRequestTimer does not expire. The tChunkReceiverRequest time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Response Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.18.3 ChunkSenderResponseTimer The ChunkSenderResponseTimer is used during a Chunked Message transmission. The ChunkSenderResponseTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Request is responded to within a bounded time of tChunkSenderResponse. Failure to receive the expected response is detected when the ChunkSenderResponseTimer expires. The ChunkSenderResponseTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Request Message, is received by the PHY Layer. The ChunkSenderResponseTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is transmitted by the PHY Layer.  A Message other than a Chunk is received from the Protocol Layer. The receiver of a Chunk Request requiring a Chunk Response Shall respond with a Chunk Response within tChunkReceiverResponse in order to ensure that the sender's ChunkSenderResponseTimer does not expire. The tChunkReceiverResponse time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.19 Programmable Power Supply Timers 6.6.19.1 SinkPPSPeriodicTimer The SinkPPSPeriodicTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSRequest when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is sent periodically as a keep alive mechanism. SinkPPSPeriodicTimer Shall be re-initialized and restarted on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any received Message, that causes the Sink to enter the PE_SNK_Ready state. The Sink Shall stop the SinkPPSPeriodicTimer on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any Message, or the last bit of any Signaling is received, by the PHY Layer, from the Source and by the Sink that causes the Sink to leave the PE_SNK_Ready state. 6.6.19.2 SourcePPSCommTimer The SourcePPSCommTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSTimeout when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is received periodically as a keep alive mechanism. Page 260 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SourcePPSCommTimer Shall be re-initialized and restarted when, after receiving any Message that causes the Source to enter the PE_SRC_Ready state, the last bit of the corresponding GoodCRC Message EOP is transmitted by the PHY Layer. The Source Shall stop the SourcePPSCommTimer when:  After receiving any Message that causes the Source to leave the PE_SRC_Ready state, the last bit of the of the corresponding GoodCRC Message EOP is sent by the PHY Layer, or  The last bit of any Signaling is received by the PHY Layer from the Sink by the Source that causes the Source to leave the PE_SRC_Ready state. When the SourcePPSCommTimer times out the Source Shall issue Hard Reset Signaling. 6.6.20 tEnterUSB The DFP Shall send the Enter_USB Message within tEnterUSB of either:  The last bit of the GoodCRC acknowledging the Data_Reset_Complete Message in response to the Data_Reset Message or  A PD Connection, specifically the last bit of the GoodCRC acknowledging the Source_Capabilities Mes- sage after the initial entry into the PE_SRC_Send_Capabilities state or  The last bit of the GoodCRC acknowledging the Accept Message in response to the DR_Swap Message Failure by the DFP to meet this timeout parameter can result in the ports not transitioning into [USB4] operation. Any AMS initiated by the UFP prior to receiving the Enter_USB Message will delay reception of the Enter_USB Message and [USB4] operation, therefore a USB4® -capable UFP Should Not initiate any AMS until the DFP has been given time to send the Enter_USB Message. 6.6.21 EPR Timers 6.6.21.1 SinkEPREnterTimer Timer The SinkEPREnterTimer is used to ensure the EPR Mode entry process completes within tEnterEPR. The Sink Shall start the timer when it sees the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 1 (Enter). The Sink Shall stop the timer when the last bit of the corresponding GoodCRC Message EOP, corresponding to the received EPR_Mode Message with the Action field set to 3 (Enter Succeeded), has been transmitted by the PHY Layer. If the timer expires the Sink Shall send a Soft_Reset Message. 6.6.21.2 SinkEPRKeepAlive Timer The SinkEPRKeepAliveTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSinkEPRKeepAlive. The Sink Shall initialize and run this timer upon entry into the PE_SNK_Ready State when in EPR Mode and Shall stop it upon exit from the PE_SNK_Ready when in EPR Mode. While operating in EPR Mode, the Sink Shall stop the SinkEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Source, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Sink Shall send an EPR_KeepAlive Message. 6.6.21.3 SourceEPRKeepAlive Timer The SourceEPRKeepAliveTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSourceEPRKeepAlive. The Source Shall initialize Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 261 and run this timer upon entry into the PE_SRC_Ready State when in EPR Mode and Shall disable it upon exit from the PE_SRC_Ready State when EPR Mode. While operating in EPR Mode, the Source Shall stop the SourceEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Sink, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Source Shall send Hard Reset Signaling. 6.6.21.4 tEPRSourceCableDiscovery After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap an EPR Source Shall discover the Cable Plug within tEPRSourceCableDiscovery of entering the First Explicit Contract. The EPR Source Shall send the Discover Identity REQ Command, to the Cable Plug, within tEPRSourceCableDiscovery of receiving the GoodCRC Message acknowledging the PS_RDY Message as part of the Explicit Contract Negotiation. Note: If the EPR Source is not the VCONN Source, tEPRSourceCableDiscovery, will also include the time needed for the VCONN Swap. Page 262 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.22 Time Values and Timers Table 6.68, "Time Values" summarizes the values for the timers listed in this section. For each Timer Value, a given implementation Shall pick a fixed value within the range specified. Table 6.69, "Timers" lists the timers. Table 6.68 Time Values Parameter Value (min) Value (Nom) Value (max) Units Reference tACTempUpdate 500 ms Section 6.5.2.2.1 tBISTContMode 30 45 60 ms Section 6.6.7.2 tBISTCarrierMode 300 ms Section 6.6.7.1 tBISTSharedTestMode 1 s Section 6.6.7.3 tCableMessage 750 µs Section 6.6.14 tCapabilitiesMismatchResponse 2 s Section 6.4.2.3 tChunkingNotSupported 40 45 50 ms Section 6.6.18.1 tChunkReceiverRequest 15 ms Section 6.6.18.2 tChunkReceiverResponse 15 ms Section 6.6.18.3 tChunkSenderRequest 24 27 30 ms Section 6.6.18.2 tChunkSenderResponse 24 27 30 ms Section 6.6.18.3 tDataReset 200 225 250 ms Section 6.6.10.2 tDataResetFail 300 400 ms Section 6.6.10.3 tDataResetFailUFP 450 550 ms Section 6.6.10.4 tDiscoverIdentity 40 50 ms Section 6.6.14 tDRSwapHardReset 15 ms Section 6.6.11.3 tDRSwapWait 100 ms Section 6.6.4.3 tEnterUSB 500 ms Section 6.6.20 tEnterUSBWait 100 ms Section 6.6.4.7 tEnterEPR 450 500 550 ms Section 6.6.21.1 tEPRSourceCableDiscovery 2 s Section 6.6.21.4 tFirstSourceCap 250 ms Section 6.6.3.3 tFRSwap5V 15 ms Section 6.6.17.1 tFRSwapComplete 15 ms Section 6.6.17.2 tFRSwapInit 15 ms Section 6.6.17.3 tHardReset 5 ms Section 6.3.13 tHardResetComplete 4 4.5 5 ms Section 6.6.9 tSourceEPRKeepAlive 0.750 0.875 1.000 s Section 6.6.21.3 tSinkEPRKeepAlive 0.250 0.375 0.500 s Section 6.6.21.2 tNoResponse 4.5 5.0 5.5 s Section 6.6.6 tPPSRequest 10 s Section 6.6.19.1 tPPSTimeout 12.0 13.5 15.0 s Section 6.6.19.2 tProtErrHardReset 15 ms Section 6.6.11.4 tProtErrSoftReset 15 ms Section 6.6.9.2 tPRSwapWait 100 ms Section 6.6.4.2 tPSHardReset 25 30 35 ms Section 6.6.11.2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 263 tPSSourceOff SPR Mode 750 835 920 ms Section 6.6.5.2 EPR Mode 1120 1260 1400 tPSSourceOn SPR Mode 390 435 480 ms Section 6.6.5.3 tPSTransition SPR Mode 450 500 550 ms Section 6.6.5.1 EPR Mode 830 925 1020 tReceive 0.9 1.0 1.1 ms Section 6.6.1 tReceiverResponse 15 ms Section 6.6.2 tRetry 195 µs Section 6.6.1 tSenderResponse 27 30 33 ms Section 6.6.2 tSinkDelay 5 ms Section 5.7 tSinkRequest 100 ms Section 6.6.4.1 tSinkTx 16 18 20 ms Section 6.6.16 tSoftReset 15 ms Section 6.8.1 tSrcHoldsBus 50 ms Section 8.3.3.2 tSwapSinkReady 15 ms Section 6.6.8.1 tSwapSourceStart 20 ms Section 6.6.8.1 tTransmit 195 µs Section 6.6.1 tTypeCSendSourceCap 100 150 200 ms Section 6.6.3.1 tTypeCSinkWaitCap 310 465 620 ms Section 6.6.3.2 tVCONNSourceDischarge 160 200 240 ms Section 6.6.10.1 tVCONNSourceOff 25 ms Section 6.6.13 tVcONNSourceOn 50 ms Section 6.3.11 tVCONNSourceTimeout 100 150 200 ms Section 6.6.13 tVCONNSwapWait 100 ms Section 6.6.4.4 tVCONNSwapDelayDFP 100 ms Section 6.6.4.5 tVCONNSwapDelayUFP 500 ms Section 6.6.4.6 tVDMBusy 50 ms Section 6.6.12.4 tVDMEnterMode 25 ms Section 6.6.12.2 tVDMExitMode 25 ms Section 6.6.12.3 tVDMReceiverResponse 15 ms Section 6.6.12.1 tVDMSenderResponse 24 27 30 ms Section 6.6.12.1 tVDMWaitModeEntry 40 45 50 ms Section 6.6.12.2 tVDMWaitModeExit 40 45 50 ms Section 6.6.12.3 Table 6.68 Time Values (Continued) Parameter Value (min) Value (Nom) Value (max) Units Reference Page 264 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.69 Timers Timer Parameter Used By Reference BISTContModeTimer tBISTContMode Policy Engine Section 6.6.7.2 ChunkingNotSupportedTimer tChunkingNotSupported Policy Engine Section 6.6.18.1 ChunkSenderRequestTimer tChunkSenderRequest Protocol Layer Section 6.6.18.2 ChunkSenderResponseTimer tChunkSenderResponse Protocol Layer Section 6.6.18.3 CRCReceiveTimer tReceive Protocol Layer Section 6.6.1 DataResetFailTimer tDataResetFail Policy Engine Section 6.6.10.3 DataResetFailUFPTimer tDataResetFailUFP Policy Engine Section 6.6.10.4 DiscoverIdentityTimer tDiscoverIdentity Policy Engine Section 6.6.15 HardResetCompleteTimer tHardResetComplete Protocol Layer Section 6.6.9 NoResponseTimer tNoResponse Policy Engine Section 6.6.6 PSHardResetTimer tPSHardReset Policy Engine Section 6.6.11.2 PSSourceOffTimer tPSSourceOff Policy Engine Section 6.6.5.2 PSSourceOnTimer tPSSourceOn Policy Engine Section 6.6.5.3 PSTransitionTimer tPSTransition Policy Engine Section 6.6.5.1 SenderResponseTimer tSenderResponse Policy Engine Section 6.6.2 SinkEPREnterTimer tEnterEPR Policy Engine Section 6.6.21.1 SinkEPRKeepAliveTimer tSinkEPRKeepAlive Policy Engine Section 6.6.21.2 SinkPPSPeriodicTimer tPPSRequest Policy Engine Section 6.6.19.1 SinkRequestTimer tSinkRequest Policy Engine Section 6.6.4 SinkWaitCapTimer tTypeCSinkWaitCap Policy Engine Section 6.6.3.2 SourceCapabilityTimer tTypeCSendSourceCap Policy Engine Section 6.6.3.1 SourceEPRKeepAliveTimer tSourceEPRKeepAlive Policy Engine Section 6.6.21.3 SourcePPSCommTimer tPPSTimeout Policy Engine Section 6.6.19.2 SinkTxTimer tSinkTx Protocol Layer Section 6.6.16 SwapSourceStartTimer tSwapSourceStart Policy Engine Section 6.6.8.1 VCONNDischargeTimer tVCONNSourceDischarge Policy Engine Section 6.6.10.1 VCONNOnTimer tVCONNSourceTimeout Policy Engine Section 6.6.13.1 VDMModeEntryTimer tVDMWaitModeEntry Policy Engine Section 6.6.12.2 VDMModeExitTimer tVDMWaitModeExit Policy Engine Section 6.6.12.3 VDMResponseTimer tVDMSenderResponse Policy Engine Section 6.6.12.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 265 6.7 Counters 6.7.1 MessageID Counter The MessageIDCounter is a rolling counter, ranging from 0 to nMessageIDCount, used to detect duplicate Messages. This value is used for the MessageID field in the Message Header of each transmitted Message. Each Port Shall maintain a copy of the last MessageID value received from its Port Partner. Devices that support multiple ports, such as Hubs, Shall maintain copies of the last MessageID on a per Port basis. A Port which communicates using SOP* Packets Shall maintain copies of the last MessageID for each type of SOP* it uses. The transmitter Shall use the MessageID in a GoodCRC Message to verify that a particular Message was received correctly. The receiver Shall use the MessageID to detect duplicate Messages. 6.7.1.1 Transmitter Usage The Transmitter Shall use the MessageID as follows:  Upon receiving either Hard Reset Signaling, or a Soft_Reset Message, the transmitter Shall set its MessageIDCounter to zero and re-initialize its retry mechanism.  If a GoodCRC Message with a MessageID matching the MessageIDCounter is not received before the CRCReceiveTimer expires, it Shall retry the same Packet up to nRetryCount times using the same MessageID.  If a GoodCRC Message is received with a MessageID matching the current MessageIDCounter before the CRCReceiveTimer expires, the transmitter Shall re-initialize its retry mechanism and increment its MessageIDCounter.  If the Message is aborted by the Policy Engine, the transmitter Shall delete the Message from its transmit buffer, re-initialize its retry mechanism and increment its MessageIDCounter. 6.7.1.2 Receiver Usage The Receiver Shall use the MessageID as follows:  When the first good Packet is received after a reset, the receiver Shall store a copy of the received MessageID value.  For subsequent Messages, if MessageID value in a received Message is the same as the stored value, the receiver Shall return a GoodCRC Message with that MessageID value and drop the Message (this is a retry of an already received Message). Note: This Shall Not apply to the Soft_Reset Message which always has a MessageID value of zero.  If MessageID value in the received Message is different than the stored value, the receiver Shall return a GoodCRC Message with the new MessageID value, store a copy of the new MessageID value and pro- cess the Message. 6.7.2 Retry Counter The RetryCounter is used by a Port whenever there is a Message transmission failure (timeout of CRCReceiveTimer). If the nRetryCount retry fails, then the link Shall be reset using the Soft Reset mechanism. The following rules apply to retries when there is a Message transmission failure (see also Section 6.12.2.2, "Protocol Layer Message Transmission"):  Cable Plugs Shall Not retry Messages.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are not Chunked (Chunked flag set to zero) Shall Not be retried. Page 266 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Extended Messages of Data Size ≤ MaxExtendedMsgLegacyLen (Chunked flag set to zero or one) Shall be retried.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are Chunked (Chunked flag set to one) individual Chunks Shall be retried. When Messages are not retried, then the RetryCounter is not used. Higher layer protocols are expected to accommodate Message delivery failure or failure to receive a GoodCRC Message. 6.7.3 Hard Reset Counter The HardResetCounter is used to retry the Hard Reset whenever there is no response from the remote device (see Section 6.6.6, "NoResponseTimer"). Once the Hard Reset has been retried nHardResetCount times then it Shall be assumed that the remote device is non-responsive. 6.7.4 Capabilities Counter The CapsCounter is used to count the number of Source_Capabilities Messages which have been sent by a Source at power up or after a Hard Reset. Implementation of the CapsCounter is Optional but May be used by any Source which wishes to preserve power by not sending Source_Capabilities Messages after a period of time. When the CapsCounter is implemented and the Source detects that a Sink is Attached then after nCapsCount Source_Capabilities Messages have been sent the Source Shall decide that the Sink is non-responsive, stop sending Source_Capabilities Messages and disable PD. A Sink Shall use the SinkWaitCapTimer to trigger the resending of Source_Capabilities Messages by a USB Power Delivery capable Source which has previously stopped sending Source_Capabilities Messages. Any Sink which is Attached and does not detect a Source_Capabilities Message, Shall issue Hard Reset Signaling when the SinkWaitCapTimer times out in order to reset the Source. Resetting the Source Shall also reset the CapsCounter and restart the sending of Source_Capabilities Messages. 6.7.5 Discover Identity Counter When sending Discover Identity Messages to a Cable Plug a Port Shall maintain a count of Messages sent (DiscoverIdentityCounter). No more than nDiscoverIdentityCount Discover Identity Messages Shall be sent by the Port without receiving a GoodCRC Message response. A VCONN Swap Shall reset the DiscoverIdentityCounter. 6.7.6 VDMBusyCounter When sending Responder BUSY responses to a Structured Vendor_Defined Message a UFP or Cable Plug Shall maintain a count of Messages sent (VDMBusyCounter). No more than nBusyCount Responder BUSY responses Shall be sent. The VDMBusyCounter Shall be reset on sending a non-BUSY response. Products wishing to meet [USB Type-C 2.4] requirements for Alternate Mode entry Should use an nBusyCount of 1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 267 6.7.7 Counter Values and Counters Table 6.70, "Counter Parameters" lists the counters used in this section and Table 6.71, "Counters" shows the corresponding parameters. Table 6.70 Counter Parameters Parameter Value Reference nBusyCount 5 Section 6.7.6 nCapsCount 50 Section 6.7.4 nDiscoverIdentityCount 20 Section 6.7.5 nHardResetCount 2 Section 6.7.3 nMessageIDCount 7 Section 6.7.1 nRetryCount 2 Section 6.7.2 Table 6.71 Counters Counter Max Reference CapsCounter nCapsCount Section 6.7.4 DiscoverIdentityCounter nDiscoverIdentityCount Section 6.7.5 HardResetCounter nHardResetCount Section 6.7.3 MessageIDCounter nMessageIDCount Section 6.7.1 RetryCounter nRetryCount Section 6.7.2 VDMBusyCounter nBusyCount Section 6.7.6 Page 268 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.8 Reset Resets are a necessary response to protocol or other error conditions. USB Power Delivery defines four different types of reset:  Soft Reset, which resets protocol.  Data Reset which resets the USB Communications.  Hard Reset which resets both the power supplies and protocol  Cable Reset which resets the cable. 6.8.1 Soft Reset and Protocol Error A Soft_Reset Message is used to cause a Soft Reset of protocol communication when this has broken down in some way. It Shall Not have any impact on power supply operation but is used to correct a Protocol Error occurring during an Atomic Message Sequence (AMS). The Soft Reset May be triggered by either Port Partner in response to the Protocol Error. Protocol Errors are any unexpected Message during an AMS. If the first Message in an AMS has been passed to the Protocol Layer by the Policy Engine but has not yet been sent (i.e., a GoodCRC Message acknowledging the Message has not been received) when the Protocol Error occurs, the Policy Engine Shall Not issue a Soft Reset but Shall return to the PE_SNK_Ready or PE_SRC_Ready state and then process the incoming Message. If the incoming Message is an Unexpected Message received in the PE_SNK_Ready or PE_SRC_Ready state, the Policy Engine Shall issue a Soft Reset. If the Protocol Error occurs during an AMS this Shall lead to a Soft Reset in order to re-synchronize the Policy Engine state machines (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams") except when the voltage is transition when a Protocol Error Shall lead to a Hard Reset (see Section 6.6.11.4, "tProtErrHardReset" and Section 8.3.3.2, "Policy Engine Source Port State Diagram"). Details of AMS's can be found in Section 8.3.2.1.3, "Atomic Message Sequences". An Unrecognized Message or Unsupported Message received in the PE_SNK_Ready or PE_SRC_Ready states, Shall Not cause a Soft_Reset Message to be generated but instead a Not_Supported Message Shall be generated. A Soft_Reset Message Shall be sent regardless of the Rp value either SinkTxOK or SinkTxNG if it is the correct response in that state. Note: This means that a Soft_Reset Message can be sent during an AMS regardless of the Rp value either SinkTxOK or SinkTxNG when responding to a Protocol Error. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 269 Table 6.72, "Response to an incoming Message (except VDM)" and Table 6.73, "Response to an incoming VDM" summarize the responses that Shall be made to an incoming Message including VDMs. A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure resulting in a Soft Reset (see Section 6.6.9.1, "tSoftReset"). A Soft Reset Shall impact the USB Power Delivery layers in the following ways:  PHY Layer: Reset not required since the PHY Layer resets on each Packet transmission/reception.  Protocol Layer: Reset MessageIDCounter, RetryCounter and state machines. Table 6.72 Response to an incoming Message (except VDM) Recipient’s Power Role Recipient’s state Incoming Message Recognized Unrecognized Supported Unsupported Expected Unexpected Source PE_SRC_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (power not transitioning1) Process Message Soft_Reset Message2 During AMS (power transitioning1) Process Message Hard Reset Signaling Sink PE_SNK_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (not power transitioned) Process Message Soft_Reset Message2 During AMS (power transitioned) Process Message Hard Reset Signaling 1) “Power transitioning” means the Policy Engine is in PE_SRC_Transition_Supply State or PE_SNK_Transition_Sink State or PE_FRS_SNK_SRC_Start_AMS State. 2) The Soft_Reset Message Shall be sent using the SOP* of the incoming Message. 3) The Not_Supported Message Shall be sent using the SOP* of the incoming Message. Table 6.73 Response to an incoming VDM Recipient's Role Unstructured VDM Structured VDM Supported Unsupported Unrecognized Supported Unsupported Unrecognized DFP or UFP Defined by vendor Not_Supported Message Not_Supported Message See Section 6.13.5 Not_Supported Message NAK Command Cable Plug Defined by vendor Message Ignored Message Ignored See Section 6.13.5 Message Ignored NAK Command Page 270 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Policy Engine: Reset state dependent behavior by performing an Explicit Contract Negotiation.  Power supply: Shall Not change. Note: When in SPR Mode the Source sends a Source_Capabilities Message and when in EPR Mode the Source sends an EPR_Source_Capabilities Message. A Soft Reset is performed using an AMS (see Table 8.8, "AMS: Soft Reset"). Message numbers Shall be set to zero prior to sending the Soft_Reset/Accept Message since the issue might be with the counters. The sender of a Soft_Reset Message Shall reset its MessageIDCounter and RetryCounter, the receiver of the Message Shall reset its MessageIDCounter and RetryCounter before sending the Accept Message response. Any failure in the Soft Reset process will trigger a Hard Reset when SOP Packets are being used or Cable Reset, sent by the DFP only, for any other SOP* Packets; for example a GoodCRC Message is not received during the Soft Reset process (see Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). 6.8.2 Data Reset A Data_Reset Message is used by a Port to reset its USB data connection and to exit all Alternate Modes both with its Port Partner and in the Cable Plug(s).  The Data Reset process May be initiated by either Port Partner sending a Data_Reset Message. A Data Reset impacts USB Power Delivery in the following ways:  Shall Not change the Port Power Roles (Source/Sink) or Port Data Roles (DFP/UFP).  Shall Not change the existing Explicit Contract.  Shall cause all Active Modes to be exited.  Shall reset the cable by Power cycling VCONN.  The DFP Shall become the VCONN Source.  If the Data Reset process fails, then the Port Shall enter the ErrorRecovery State as defined in [USB Type-C 2.4]. See Section 6.3.14, "Data_Reset Message" for details of Data Reset operation. 6.8.3 Hard Reset Hard Resets are signaled by an ordered set as defined in Section 5.6.4, "Hard Reset". Both the sender and recipient Shall cause their power supplies to return to their default states (see Section 7.3.3.1, "Source Initiated Hard Reset" and Section 7.3.3.2, "Sink Initiated Hard Reset" for details of voltage transitions). In addition, their respective Protocol Layers Shall be reset as for the Soft Reset. This allows the Attached devices to be in a state where they can re-establish USB PD communication. Hard Reset is retried up to nHardResetCount times (see also Section 6.6.6, "NoResponseTimer" and Section 6.7.3, "Hard Reset Counter"). Note: Even though VBUS drops to vSafe0V during a Hard Reset a Sink will not see this as a disconnect since this is expected behavior. A Hard Reset Shall Not cause any change to either the Rp/Rd resistor being asserted. If there has been a Data Role Swap the Hard Reset Shall cause the Port Data Role to be changed back to DFP for a Port with the Rp resistor asserted and UFP for a Port with the Rd resistor asserted. When VCONN is supported (see [USB Type-C 2.4]) the Hard Reset Shall cause the Port with the Rp resistor asserted to supply VCONN and the Port with the Rd resistor asserted to turn off VCONN. In effect the Hard Reset will revert the Ports to their default state based on their CC line resistors. Removing and reapplying VCONN from the Cable Plugs also ensures that they re-establish their configuration as either SOP’ or SOP’’ based on the location of VCONN (see [USB Type-C 2.4]). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 271 If the Hard Reset is insufficient to clear the error condition, then the Port Shall use USB Type-C ErrorRecovery as defined in [USB Type-C 2.4]. A Sink Shall be able to send Hard Reset Signaling regardless of the value of Rp (see Section 5.7, "Collision Avoidance"). 6.8.3.1 Cable Plugs and Hard Reset Cable Plugs Shall Not generate Hard Reset Signaling but Shall monitor for Hard Reset Signaling between the Port Partners and Shall reset when this is detected (see Section 8.3.3.25.2.2, "Cable Plug Hard Reset State Diagram"). The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. 6.8.3.2 Modal Operation and Hard Reset A Hard Reset Shall cause EPR Mode and all Active Modes to be exited by both Port Partners and any Cable Plugs (see Section 6.4.4.3.4, "Enter Mode Command"). 6.8.4 Cable Reset Cable Resets are signaled by an ordered set as defined in Section 5.6.5, "Cable Reset". Both the sender and recipient of Cable Reset Signaling Shall reset their respective Protocol Layers. The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. The DFP must be supplying VCONN prior to a Cable Reset. If VCONN has been turned off the DFP Shall turn on VCONN prior to generating Cable Reset Signaling. If there has been a VCONN Swap and the UFP is currently supplying VCONN, the DFP Shall perform a VCONN Swap such that it is supplying VCONN prior to generating Cable Reset Signaling. Only a DFP Shall generate Cable Reset Signaling. A DFP Shall only generate Cable Reset Signaling within an Explicit Contract. A Cable Reset Shall cause all Active Modes in the Cable Plugs to be exited (see Section 6.4.4.3.4, "Enter Mode Command"). Page 272 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.9 Accept, Reject and Wait The recipient of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message Shall respond by sending one of the following responses:  An Accept Message in response to a Valid request which can be serviced immediately (see Section 6.3.3, "Accept Message").  A Wait Message in response to a Valid request which cannot be serviced immediately but could be ser- viced at a later time (see Section 6.3.12, "Wait Message").  A Reject Message in response to an Invalid request or a request which is outside of the device's design Capabilities (see Section 6.3.4, "Reject Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 273 6.10 Collision Avoidance To avoid Message collisions due to asynchronous Messaging sent from the Sink, the Source sets Rp to SinkTxOK to indicate to the Sink that it is OK to initiate an AMS. When the Source wishes to initiate an AMS, it sets Rp to SinkTxNG. When the Sink detects that Rp is set to SinkTxOK it May initiate an AMS. When the Sink detects that Rp is set to SinkTxNG it Shall Not initiate an AMS and Shall only send Messages that are part of an AMS the Source has initiated. Note: This restriction applies to SOP* AMS's i.e., for both Port to Port and Port to Cable Plug communications. If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. Note: A Sink can still send Hard Reset Signaling at any time. Page 274 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.11 Message Discarding On receiving a received Message on SOP, the Protocol Layer Shall Discard any pending SOP* Messages. A received Message on SOP’/SOP’’ Shall Not cause any pending SOP* Messages to be Discarded. It is assumed that Messages using SOP’/SOP’’ constitute a simple request/response AMS, with the Cable Plug providing the response so there is no reason for a pending SOP* Message to be Discarded. There can only be one AMS between the Port Partners, and these also take priority over Cable Plug communications so a Message received on SOP will always cause a Message pending on SOP* to be Discarded. Table 6.74, "Message Discarding" for details of the Messages that Shall/ Shall Not be Discarded. Table 6.74 Message Discarding Message pending transmission Message received Message to be Discarded SOP SOP Outgoing Message SOP SOP’/SOP’’ Incoming Message SOP’ SOP Outgoing Message SOP’ SOP’ Incoming Message SOP’ SOP’’ Incoming Message SOP’’ SOP Outgoing Message SOP’’ SOP’ Incoming Message SOP’’ SOP’’ Incoming Message Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 275 6.12 State behavior 6.12.1 Introduction to state diagrams used in Chapter 6 The state diagrams defined in Section 6.12, "State behavior" are Normative and Shall define the operation of the Power Delivery Protocol Layer. Note: These state diagrams are not intended to replace a well written and robust design. Figure 6.57, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state and in some states "Actions on exit" a list of actions carried out on exiting the state. Figure 6.57 Outline of States Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&." The inverse of a condition is shown with a "NOT" in front of the condition. In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams. Figure 6.57, "Outline of States" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the referenced state. Figure 6.58 References to states Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the state it is referenced. As soon as the state is exited then the timer is no longer active. Timeouts of the timers are listed as conditions on state transitions. Conditions listed on state transitions will come from one of three sources: <Name of State> Actions on entry: “List of actions to carry out on entering the state” Actions on exit: “List of actions to carry out on exiting the state” <Name of reference state> (<DFP | UFP>) Page 276 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Messages received from the PHY Layer.  Events triggered within the Protocol Layer e.g., timer timeouts  Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.) 6.12.2 State Operation The following section details Protocol Layer State Operation when sending and receiving SOP* Packets. For each SOP’ Communication being sent and received there Shall be separate Protocol Layer Transmission and Protocol Layer Reception and Hard Reset State Machine instances, with their own counter and timer instances. When Chunking is supported there Shall be separate Chunked Tx, Chunked Tx, and Chunked Message Router State Machine instances. Soft Reset Shall only apply to the State Machine instances it is targeted at based on the type of SOP* Packet used to send the Soft_Reset Message. The Hard Reset State Machine (including Cable Reset) Shall apply simultaneously to all Protocol Layer State Machine instances active in the DFP, UFP and Cable Plug (if present). 6.12.2.1 Protocol Layer Chunking 6.12.2.1.1 Architecture of Device Including Chunking Layer The Chunking component resides in the Protocol Layer between the Policy Engine and Protocol Tx/Rx. Figure 6.59, "Chunking architecture Showing Message and Control Flow" illustrates the relationship between components. The Chunking Layer comprises three related state machines:  Chunked Rx.  Chunked Tx.  Chunked Message Router. Note: The consequence of this architecture is that the Policy Engine deals entirely in Unchunked Messages. It will not receive (and might not respond to) a Message until all the related chunks have been collated. If a PD device or Cable Plug has no requirement to handle any Message requiring more than one Chunk of any Extended Message, it May omit the Chunking Layer. In this case it Shall implement the ChunkingNotSupportedTimer to ensure compatible operation with partners which support Chunking (see Section 6.6.18.1, "ChunkingNotSupportedTimer" and Section 8.3.3.6, "Not Supported Message State Diagrams"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 277 Figure 6.59 Chunking architecture Showing Message and Control Flow 6.12.2.1.1.1 Optional Abort Mechanism Long Chunked Messages bring with them the potential problem that they could prevent urgent Messages from being transmitted in a timely manner. An Optional Abort mechanism is provided to remedy this problem. The Abort Flag referred to in the diagrams below May be set and examined by the Policy Engine. The specific means are left to the implementer. 6.12.2.1.1.2 Aborting Sending a Long-Chunked Message A long-Chunked Message being sent May be aborted by setting the Optional Abort Flag. The Message Shall be considered aborted when the Abort Flag is again cleared by the Chunked Tx state machine. 6.12.2.1.1.3 Aborting Receiving a Long-Chunked Message If the Optional Abort mechanism has been implemented, any Message sent while a Chunked Message receive is in progress will result in an error report being received by the Policy Engine, to indicate that the Message request has been Discarded. If the Message was urgent the Policy Engine might set the Abort Flag, which will result in the incoming Chunked Message being aborted. The Abort Flag being cleared by the Chunked Rx state machine indicates that the urgent Message can now be sent. 6.12.2.1.2 Chunked Rx State Diagram Figure 6.60, "Chunked Rx State Diagram" shows the state behavior for the Chunked Rx State Machine. This recognizes whether Chunked received Messages are involved and deals with requesting chunks when they are. It also performs validity checks on all Messages related to Chunking. Policy Engine Protocol Layer Rx Protocol Layer Tx PHY Layer Rp Control or Detection Chunked Rx Chunked Tx Chunking Protocol Layer Hard Reset Chunked Message Router AMS Notification Page 278 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.60 Chunked Rx State Diagram 6.12.2.1.2.1 RCH_Wait_For_Message_From_Protocol_Layer State The Chunked Rx State Machine Shall enter the RCH_Wait_For_Message_From_Protocol_Layer state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine clears the Extended Rx Buffer and clears the Optional Abort Flag. In the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine waits until the Chunked Message Router passes up a received Message. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  A non-Extended Message is passed up from the Chunked Message Router.  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are not doing Chunking, and the Message has its Chunked bit set to 0b. The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are doing Chunking, and the Message has its Chunked bit set to 1b. 6.12.2.1.2.2 RCH_Pass_Up_Message State On entry to the RCH_Pass_Up_Message state the Chunked Rx state machine Shall pass the received Message to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Message has been passed. Transmission Error from Protocol Layer | Message Received from Protocol Layer Other Message Received from Protocol Layer | ChunkSenderResponseTimer timeout RCH_Pass_Up_Message Actions on entry: Pass Message to Policy Engine RCH_Wait_For_Message_From_Protocol_Layer Actions on entry: Clear Extended Rx Buffer Clear Abort Flag RCH_Report_Error Actions on entry: Report Error to Policy Engine. If a Message was received, pass it to the Policy Engine. RCH_Processing_ Extended_Message Actions on entry: If first chunk: set Chunk_Number_Expected = 0 and Num bytes received = 0 If expected Chunk Number: Append data to Extended_Message_Buffer; Increment Chunk_Number_Expected and adjust Num bytes received. RCH_Requesting_Chunk Actions on entry: Send notification SRT_Stop to SenderResponseTimer State Machine. Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. RCH_Waiting_Chunk Actions on entry: Start ChunkSenderResponseTimer3 Send notification SRT_Start to SenderResponseTimer State Machine.3 Start Message not Complete Message Transmitted received from Protocol Layer Unexpected Chunk Number Reported Chunked != Chunking1 Received Non-Extended Message | (Received Extended Message & (Chunking1 = 0 & Chunked = 0) ) Message is Complete (Num bytes received >= specified Data Size)2 Message Passed Chunk Response Received from Protocol Layer Received Extended Message & (Chunking1 = 1 & Chunked = 1) Any Message Received and not in state RCH_Waiting_Chunk or RCH_Wait_For_Message_From_ Protocol_Layer Abort Flag Set Soft Reset occured | Exit from Hard Reset 1) Chunking is an internal state that is set to 1 if the ‘Unchunked Extended Messages Supported’ bit in either Source Capabilities or Request is 0. It defaults to 1 and is set after the first exchange of Source Capabilities and Request. It is also set to 1 for SOP’ or SOP’’ communication. 2) Additional bytes received over specified Data Size will be because of padding in the last chunk. 3) This state is responsible for starting two timers of similar length. The implementor Should mitigate against more than one of these timers resulting in recovery action. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 279 6.12.2.1.2.3 RCH_Processing_Extended_Message State On entry to the RCH_Processing_Extended_Message state the Chunked Rx state machine Shall:  If this is the first chunk:  Set Chunk_Number_Expected = 0.  Set Num bytes received = 0.  If chunk contains the expected Chunk Number:  Append its data to the Extended_Message_Buffer.  Increment Chunk_Number_Expected.  Adjust Num bytes received. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  The Message is complete (i.e., Num bytes received >= specified Data Size. Note: The inequality allows for padding bytes in the last chunk, which are not actually part of the Extended Mes- sage). The Chunked Rx State Machine Shall transition to the RCH_Requesting_Chunk state when:  The Message is not yet complete. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  An unexpected Chunk Number is received. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Optional Abort Flag is set. 6.12.2.1.2.4 RCH_Requesting_Chunk State On entry to the RCH_Requesting_Chunk state the Chunked Rx state machine Shall:  Send notification SRT_Stop to SenderResponseTimer state machine (see Section 8.3.3.1.1, "SenderResponseTimer State Diagram").  Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. The Chunked Rx State Machine Shall transition to the RCH_Waiting_Chunk state when:  Message Transmitted is received from the Protocol Layer. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  Transmission Error is received from the Protocol Layer, or  A Message is received from the Protocol Layer. 6.12.2.1.2.5 RCH_Waiting_Chunk State On entry to the RCH_Waiting_Chunk state the Chunked Rx state machine Shall:  Start the ChunkSenderResponseTimer.  Send notification SRT_Start to SenderResponseTimer state machine (see SSection 8.3.3.1.1, "SenderResponseTimer State Diagram"). The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  A Chunk is received from the Protocol Layer. Page 280 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  A Message, other than a Chunk, is received from the Protocol Layer, or  The ChunkSenderResponseTimer expires. 6.12.2.1.2.6 RCH_Report_Error State The Chunked Rx State Machine Shall enter the RCH_Report_Error state:  When any Message is received and the Chunked Rx State Machine is not in one of the states RCH_Waiting_Chunk or RCH_Wait_For_Message_From_Protocol_Layer. On entry to the RCH_Report_Error state the Chunked Rx state machine Shall:  Report the error to the Policy Engine.  If the state was entered because a Message was received, this Message Shall be passed to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The error has been reported.  Any Message received was passed to the Policy Engine. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 281 6.12.2.1.3 Chunked Tx State Diagram Figure 6.61, "Chunked Tx State Diagram" shows the state behavior for the Chunked Tx State Machine. This recognizes whether Chunked transmitted Messages are involved and deals with sending chunks and waiting for chunk requests when they are. It also performs validity checks on all related Messages related to Chunking. Figure 6.61 Chunked Tx State Diagram 6.12.2.1.3.1 TCH_Wait_For_Message_Request_From_Policy_Engine State The Chunked Tx State Machine Shall enter the TCH_Wait_For_Message_Request_From_Policy_Engine state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx state machine clears the Optional Abort Flag. In the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx State Machine waits until the Policy Engine sends it a Message Request. The Chunked Tx State Machine Shall transition to the TCH_Pass_Down_Message state when:  A non-Extended Message Request is received from the Policy Engine, or  A Message Request is received from the Policy Engine and the link is not Chunking. TCH_Sending_ Chunked_Message Actions on entry: TCH_ Wait_ For_Message_Request_From_Policy_Engine Actions on entry: Clear Abort Flag TCH_Pass_Down_Message Actions on entry: Pass Message to Protocol Layer TCH_Construct_ Chunked_Message Actions on entry: Construct Message Chunk and pass to Protocol Layer TCH_Wait_For_ Transmision_Complete Actions on entry: TCH_Prepare_To_Send_ Chunked_Message Actions on entry: 'Chunk Number To Send' = 0 TCH_Wait_Chunk_Request Actions on entry: Increment Chunk Number to Send Start ChunkSenderRequestTimer TCH_Report_Error Actions on entry: Report Error to Policy Engine Soft Reset occured | Exit from Hard Reset Start Non-Extended Message Request | Not Chunking Message Passed Message Transmitted received from Protocol Layer TCH_Message_Sent Actions on entry: Inform Policy Engine of Message Sent Any Message Received and not in state TCH_Wait_Chunk_Request Chunking & Extended Message Request Chunk Number Set Chunk Passed Message Transmitted from Protocol Layer & Not Last Chunk TCH_Message_Received Actions on entry: Clear Extended Message Buffers Pass Message to Chunked Rx Message passed to Chunked Rx Message Transmitted received from Protocol Layer & Last Chunk (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Supported Abort Flag Set Informed Chunk Request Rcvd & Chunk Number = Chunk Number to Send Reported Other Message Received (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Not Supported Tx Error from Protocol Layer ChunkSenderRequestTimer timeout & Chunk Number = 0 (Chunk Request Rcvd & Chunk Number != Chunk Number to Send) | (ChunkSenderRequestTimer timeout & Chunk Number > 0) Transmission Error Page 282 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Prepare_To_Send_Chunked_Message state when:  An Extended Message Request is received from the Policy Engine, and the link is Chunking. The Chunked Tx State Machine Shall Discard the Message Request and remain in the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer, and the Optional Abort Flag has not been implemented. The Chunked Tx State Machine Shall Discard the Message Request and enter the TCH_Report_Error state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer and the Optional Abort Flag has been implemented. 6.12.2.1.3.2 TCH_Pass_Down_Message State On entry to the TCH_Pass_Down_Message state the Chunked Tx State Machine Shall pass the Message to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Transmision_Complete state when:  The Message has been passed to the Protocol Layer. 6.12.2.1.3.3 TCH_Wait_For_Transmision_Complete State The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted has been received from the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.4 TCH_Message_Sent State On entry to the TCH_Message_Sent state the Chunked Tx State Machine Shall:  Inform the Policy Engine that the Message has been sent. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Policy Engine has been informed. 6.12.2.1.3.5 TCH_Prepare_To_Send_Chunked_Message State On entry to the TCH_Prepare_To_Send_Chunked_Message state the Chunked Tx State Machine Shall:  Set 'Chunk Number To Send' to zero. The Chunked Tx State Machine Shall transition to the TCH_Construct_Chunked_Message state when:  ‘Chunk Number To Send' has been set to zero. 6.12.2.1.3.6 TCH_Construct_Chunked_Message State On entry to the TCH_Construct_Chunked_Message state the Chunked Tx State Machine Shall:  Construct a Message Chunk and pass it to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Sending_Chunked_Message state when:  The Message Chunk has been passed to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 283  The Optional Abort Flag is set. 6.12.2.1.3.7 TCH_Sending_Chunked_Message State The Chunked Tx State Machine Shall transition to the TCH_Wait_Chunk_Request state when:  Message Transmitted is received from Protocol Layer and this was not the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted is received from Protocol Layer and this was the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.8 TCH_Wait_Chunk_Request State On entry to the TCH_Wait_Chunk_Request state the Chunked Tx State Machine Shall:  Increment Chunk Number to Send.  Start ChunkSenderRequestTimer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  A Chunk Request has been received and the Chunk Number does not equal Chunk Number to Send or  ChunkSenderRequestTimer has expired and Chunk Number is greater than zero. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  ChunkSenderRequestTimer has expired and Chunk Number equals zero. Note: This is the mechanism which allows the remote Port Partner or Cable Plug to omit the Chunking Layer. The Policy Engine will receive a Message Sent signal if the remote Port Partner or Cable Plug is present (GoodCRC Message received) but does not send a Chunk Request. After this the remote Port Partner will send a Not_Supported Message, or the Cable Plug will Ignore the Chunked Message. The Chunked Tx State Machine Shall transition to the TCH_Message_Received state when:  Any other Message than Chunk Request is received. 6.12.2.1.3.9 TCH_Message_Received State The Chunked Tx State Machine Shall enter the TCH_Message_Received state:  When any Message is received, and the Chunked Tx State Machine is not in the TCH_Wait_Chunk_Request state. On entry to the TCH_Message_Received state the Chunked Tx State Machine Shall:  Clear the Extended Message Buffers.  Pass the received Message to Chunked Rx Engine. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The received Message has been passed to the Chunked Rx Engine. 6.12.2.1.3.10 TCH_Report_Error State On entry to the TCH_Report_Error state the Chunked Tx State Machine Shall:  Report the error to the Policy Engine. Page 284 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The error has been reported. 6.12.2.1.4 Chunked Message Router State Diagram Figure 6.62, "Chunked Message Router State Diagram" shows the state behavior for the Chunked Message Router. This determines to which state machine an incoming Message is routed to (Chunked Rx, Chunked Tx or direct to Policy Engine). Figure 6.62 Chunked Message Router State Diagram 6.12.2.1.4.1 RTR_Wait_for_Message_From_Protocol_Layer State In the RTR_Wait_for_Message_From_Protocol_Layer state the Chunked Message Router waits until the Protocol Layer sends it a received Message. The Chunked Message Router Shall transition to the RTR_Rx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is not doing Tx Chunks. The Chunked Message Router Shall transition to the RTR_Tx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is doing Tx Chunks. 6.12.2.1.4.2 RTR_Rx_Chunks State On entry to the RTR_Rx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Rx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. RTR_Wait_for_Message_From_Protocol_Layer Actions on entry: RTR_Rx_Chunks Actions on entry: Send message to Rx Chunk Machine RTR_Tx_Chunks Actions on entry: Send message to Tx Chunk Machine Message Received from Protocol Layer & Not Doing Tx Chunks1 Message Received from Protocol Layer & Doing Tx Chunks1 Sent Soft Reset occured | Exit from Hard Reset Start Sent 1) Doing Tx Chunks means that Chunked Tx State Machine is not in the TCH_Wait_For_Message_Request_From_Policy_Engine state. 2) Messages are taken to include notification about transmission success or otherwise of Messages. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 285 6.12.2.1.4.3 RTR_Tx_Chunks State On entry to the RTR_Tx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Tx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. Page 286 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2 Protocol Layer Message Transmission 6.12.2.2.1 Common Protocol Layer Message Transmission State Diagram Figure 6.63, "Common Protocol Layer Message Transmission State Diagram" shows the state behavior, common between the Source and the Sink, for the Protocol Layer when transmitting a Message. Figure 6.63 Common Protocol Layer Message Transmission State Diagram 6.12.2.2.1.1 PRL_Tx_PHY_Layer_Reset State The Protocol Layer Shall enter the PRL_Tx_PHY_Layer_Reset state:  At startup.  As a result of a Soft Reset request being received by the PHY Layer.  On exit from a Hard Reset. On entry to the PRL_Tx_PHY_Layer_Reset state the Protocol Layer Shall reset the PHY Layer (clear any outstanding Messages and enable communications). The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  When the PHY Layer reset is complete. 6.12.2.2.1.2 PRL_Tx_Wait_for_Message_Request State In the PRL_Tx_Wait_for_Message_Request state the Protocol Layer waits until the Policy Engine directs it to send a Message.  On entry to the PRL_Tx_Wait_for_Message_Request state the Protocol Layer Shall reset the RetryCounter. Message request received from Policy Engine (except Soft Reset) Message sent to PHY Layer CRCReceiveTimer Timeout | Message discarded bus Idle2 GoodCRC response received from PHY Layer MessageID mismatch (RetryCounter ” nRetryCount) & not Cable Plug & small Extended Message3 (RetryCounter > nRetryCount) | Cable Plug | large Extended Message3 Policy Engine informed of Transmission Error MessageID match Policy Engine informed message sent PRL_Tx_Check_RetryCounter Actions on entry: If DFP or UFP increment and check RetryCounter PRL_Tx_Transmission_Error Actions on entry: Increment MessageIDCounter Inform Policy Engine of Transmission Error PRL_Tx_Construct_Message Actions on entry: Construct message Pass message to PHY Layer PRL_Tx_Wait_for_PHY_response Actions on entry: Initialize and run CRCReceiveTimer1 PRL_Tx_Match_MessageID Actions on entry: Match MessageIDCounter and response MessageID Soft Reset Message request received from Policy Engine Layer Reset Complete PRL_Tx_Message_Sent Actions on entry: Increment MessageIDCounter Inform Policy Engine message sent PRL_Tx_Layer_Reset_for_Transmit Actions on entry: Reset MessageIDCounter. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. PRL_Tx_Wait_for_Message_Request Actions on entry: Reset RetryCounter PRL_Tx_Discard_Message Actions on entry: If any message is currently awaiting transmission Discard4 and increment MessageID Counter Discarding complete Protocol Layer message reception in PRL_Rx_Store_MessageID state | Fast Role Swap signal transmitted | Fast Role Swap signal detected Start Soft Reset Message from PHY Layer | Exit from Hard Reset PRL_Tx_PHY_Layer_Reset Actions on entry: Reset PHY Layer PHY Layer reset complete 1) The CRCReceiveTimer is only started after the PHY has sent the message. If the message is not sent due to a busy channel, then the CRCReceiveTimer will not be started (see Section 6.6.1 “CRCReceiveTimer”). 2) This indication is sent by the PHY Layer when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). The CRCReceiveTimer is not running in this case since no message has been sent. 3) A “small” Extended Message is either an Extended Message with Data Size ζMaxExtendedMsgLegacyLen bytes or an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has been Chunked. A “large” Extended Message is an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has not been Chunked. 4) See Section 6.11 “Message Discarding” for details of when Messages are Discarded . Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 287 The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message request is received from the Policy Engine which is not a Soft_Reset Message. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Message request is received from the Policy Engine which is a Soft_Reset Message. 6.12.2.2.1.3 PRL_Tx_Layer_Reset_for_Transmit State On entry to the PRL_Tx_Layer_Reset_for_Transmit state the Protocol Layer Shall reset the MessageIDCounter. The Protocol Layer Shall transition Protocol Layer Message reception to the PRL_Rx_Wait_for_PHY_Message state (see Section 6.12.2.3.1, "PRL_Rx_Wait_for_PHY_Message state") in order to reset the stored MessageID. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The layer reset actions in this state have been completed. 6.12.2.2.1.4 PRL_Tx_Construct_Message State On entry to the PRL_Tx_Construct_Message state the Protocol Layer Shall construct the Message requested by the Policy Engine, or resend a previously constructed Message, and then pass this Message to the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_PHY_Response state when:  The Message has been sent to the PHY Layer. 6.12.2.2.1.5 PRL_Tx_Wait_for_PHY_Response State On entry to the PRL_Tx_Wait_for_PHY_Response state, once the Message has been sent, the Protocol Layer Shall initialize and run the CRCReceiveTimer (see Section 6.6.1, "CRCReceiveTimer"). The Protocol Layer Shall transition to the PRL_Tx_Match_MessageID state when:  A GoodCRC Message response is received from the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The CRCReceiveTimer times out.  Or the PHY Layer indicates that a Message has been Discarded due to the channel being busy but the channel is now Idle (see Section 5.7, "Collision Avoidance"). 6.12.2.2.1.6 PRL_Tx_Match_MessageID State On entry to the PRL_Tx_Match_MessageID state the Protocol Layer Shall compare the MessageIDCounter and the MessageID of the received GoodCRC Message. The Protocol Layer Shall transition to the PRL_Tx_Message_Sent state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message match. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message do not match. 6.12.2.2.1.7 PRL_Tx_Message_Sent State On entry to the PRL_Tx_Message_Sent state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine that the Message has been sent. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed that the Message has been sent. Page 288 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.1.8 PRL_Tx_Check_RetryCounter State On entry to the PRL_Tx_Check_RetryCounter state the Protocol Layer in a DFP or UFP Shall increment the value of the RetryCounter and then check it in order to determine whether it is necessary to retry sending the Message. Note: Cable Plugs do not retry Messages and so do not use the RetryCounter. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state in order to retry Message sending when:  RetryCounter ≤ nRetryCount and  This is not a Cable Plug and  This is an Extended Message with Data Size ≤ MaxExtendedMsgLegacyLen or  This is an Extended Message that has been Chunked. The Protocol Layer Shall transition to the PRL_Tx_Transmission_Error state when:  RetryCounter > nRetryCount or  This is a Cable Plug, which does not retry.  This is an Extended Message with Data Size > MaxExtendedMsgLegacyLen that has not been Chunked. 6.12.2.2.1.9 PRL_Tx_Transmission_Error State On entry to the PRL_Tx_Transmission_Error state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine of the transmission error. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed of the transmission error. 6.12.2.2.1.10 PRL_Tx_Discard_Message State Protocol Layer Message transmission Shall enter the PRL_Tx_Discard_Message state whenever:  Protocol Layer Message reception receives an incoming Message or  The Fast Role Swap Request is being transmitted (see Section 5.8.5.6, "Fast Role Swap Transmission")  The Fast Role Swap Request is detected (see Section 5.8.6.3, "Fast Role Swap Detection"). On entry to the PRL_Tx_Discard_Message state, if there is a Message queued awaiting transmission, the Protocol Layer Shall Discard the Message according to the rules in Section 6.11, "Message Discarding" and increment the MessageIDCounter. The Protocol Layer Shall transition to the PRL_Tx_PHY_Layer_Reset state when:  Discarding is complete i.e., the Message queue is empty. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 289 6.12.2.2.2 Source Protocol Layer Message Transmission State Diagram Figure 6.64, "Source Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Source when transmitting a Message. Figure 6.64 Source Protocol Layer Message Transmission State Diagram PRL_Tx_Wait_for_Message_Request PRL_Tx_Src_Sink_Tx Actions on entry: Set Rp = SinkTxOk End of AMS notification received from Policy Engine Start of AMS notification received from Policy Engine PRL_Tx_Src_Pending Actions on entry: Start SinkTxTimer PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending & SinkTxTimer timeout Message pending (except Soft Reset) & SinkTxTimer timeout Rp set PRL_Tx_Src_Source_Tx Actions on entry: Set Rp = SinkTxNG Message request from Policy Engine Page 290 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.2.1 PRL_Tx_Src_Sink_Tx State In the PRL_Tx_Src_Sink_Tx state the Source sets Rp to SinkTxOK allowing the Sink to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Sink_Tx state when:  A notification is received from the Policy Engine that the end of an AMS has been reached. On entry to the PRL_Tx_Src_Sink_Tx state the Protocol Layer Shall request the PHY Layer to Rp to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  Rp has been set. 6.12.2.2.2.2 PRL_Tx_Src_Source_Tx State In the PRL_Tx_Src_Source_Tx state the Source sets Rp to SinkTxNG allowing the Source to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Source_Tx state when:  A notification is received from the Policy Engine that an AMS will be starting. On entry to the PRL_Tx_Src_Source_Tx state the Protocol Layer Shall set Rp to SinkTxNG. The Protocol Layer Shall transition to the PRL_Tx_Src_Pending state when:  A Message request is received from the Policy Engine. 6.12.2.2.2.3 PRL_Tx_Src_Pending State In the PRL_Tx_Src_Pending state the Protocol Layer has a Message buffered ready for transmission. On entry to the PRL_Tx_Src_Pending state the SinkTxTimer Shall be initialized and run. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The pending Message request from the Policy Engine is not a Soft_Reset Message and  The SinkTxTimer times out. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  The pending Message request from the Policy Engine is a Soft_Reset Message and  The SinkTxTimer times out. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 291 6.12.2.2.3 Sink Protocol Layer Message Transmission State Diagram Figure 6.65, "Sink Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Sink when transmitting a Message. Figure 6.65 Sink Protocol Layer Message Transmission State Diagram 6.12.2.2.3.1 PRL_Tx_Snk_Start_of_AMS State In the PRL_Tx_Snk_Start_of_AMS state the Protocol Layer waits for the first Message in a Sink initiated AMS. The Protocol Layer in a Sink Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Snk_Start_of_AMS state when:  A notification is received from the Policy Engine that the next Message the Sink will send is the start of an AMS. The Protocol Layer Shall transition to the PRL_Tx_Snk_Pending state when:  A Message request is received from the Policy Engine. PRL_Tx_Wait_for_Message_Request First Message in AMS notification received from Policy Engine PRL_Tx_Snk_Pending Actions on entry: PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending Message pending (except Soft Reset) & Rp = SinkTxOk PRL_Tx_Snk_Start_of_AMS Actions on entry: Message Request from Policy Engine Page 292 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.3.2 PRL_Tx_Snk_Pending State In the PRL_Tx_Snk_Pending state the Protocol Layer has the first Message in a Sink initiated AMS ready to send and is waiting for Rp to transition to SinkTxOK before sending the Message. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message is Pending that is not a Soft_Reset Message and  Rp is set to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Soft_Reset Message is pending. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 293 6.12.2.3 Protocol Layer Message Reception Figure 6.66, "Protocol layer Message reception" shows the state behavior for the Protocol Layer when receiving a Message. Figure 6.66 Protocol layer Message reception 6.12.2.3.1 PRL_Rx_Wait_for_PHY_Message state The Protocol Layer Shall enter the PRL_Rx_Wait_for_PHY_Message state:  At startup.  As a result of a Soft Reset request from the Policy Engine.  On exit from a Hard Reset. In the PRL_Rx_Wait_for_PHY_Message state the Protocol Layer waits until the PHY Layer passes up a received Message. The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC state when:  A Message is passed up from the PHY Layer. The Protocol Layer Shall transition to the PRL_Rx_Layer_Reset_for_Receive state when:  A Soft_Reset Message is received from the PHY Layer. Message received from PHY (except Soft Reset) Message passed to Policy Engine (GoodCRC sent | Message discarded bus Idle1) MessageID <> stored MessageID | no stored value MessageID = stored MessageID Start PRL_Rx_Send_GoodCRC Actions on entry: Send GoodCRC message to PHY PRL_Rx_Store_MessageID Actions on entry: Protocol Layer message transmission transitions to PRL_Tx_Discard_Message state2. Store new MessageID Pass message to Policy Engine3 PRL_Rx_Wait_for_PHY_message Actions on entry: PRL_Rx_Check_MessageID Actions on entry: If there is a stored value compare MessageID with stored value. Soft Reset Message received from PHY Soft Reset complete PRL_Rx_Layer_Reset_for_Receive Actions on entry: Reset MessageIDCounter and clear stored MessageID value Protocol Layer message transmission transitions to PRL_Tx_PHY_Layer_Reset state. Soft Reset request from Policy Engine | Exit from Hard Reset Message discarded bus Idle1 1) This indication is sent by the PHY when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). Two alternate allowable transitions are shown. 2) In the case of a Ping message being received, in order to maintain robust communications in the presence of collisions, the outgoing message Should Not be Discarded. 3) See Section 6.11 “Message Discarding” for details of when Messages are discarded. Page 294 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.3.2 PRL_Rx_Layer_Reset_for_Receive state On entry to the PRL_Rx_Layer_Reset_for_Receive state the Protocol Layer Shall reset the MessageIDCounter and clear the stored MessageID. The Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Wait_for_Message_Request state (see Section 6.12.2.2.1.2, "PRL_Tx_Wait_for_Message_Request State"). The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC State when:  The Soft Reset actions in this state have been completed. 6.12.2.3.3 PRL_Rx_Send_GoodCRC state On entry to the PRL_Rx_Send_GoodCRC state the Protocol Layer Shall construct a GoodCRC Message and request the PHY Layer to transmit it. The Protocol Layer Shall transition to the PRL_Rx_Check_MessageID state when:  The GoodCRC Message has been passed to the PHY Layer. When the PHY Layer indicates that a Message has been Discarded due to CC being busy but CC is now Idle (see Section 5.7, "Collision Avoidance"), the Protocol Layer Shall either:  Transition to the PRL_Rx_Check_MessageID state or  Transition to the PRL_Rx_Wait_for_PHY_Message state. 6.12.2.3.4 PRL_Rx_Check_MessageID state On entry to the PRL_Rx_Check_MessageID state the Protocol Layer Shall compare the MessageID of the received Message with its stored value if a value has previously been stored. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The MessageID of the received Message equals the stored MessageID value since this is a Message retry which Shall be Discarded. The Protocol Layer Shall transition to the PRL_Rx_Store_MessageID state when:  The MessageID of the received Message does not equal the stored MessageID value since this is a new Message or  This is the first received Message and no MessageID value is currently stored. 6.12.2.3.5 PRL_Rx_Store_MessageID state On entry to the PRL_Rx_Store_MessageID state the Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Discard_Message state, replace the stored value of MessageID with the value of MessageID in the received Message and pass the Message up to the Policy Engine. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The Message has been passed up to the Policy Engine. 6.12.2.4 Hard Reset operation Figure 6.57, "Outline of States" shows the state behavior for the Protocol Layer when receiving a Hard Reset or Cable Reset request from the Policy Engine or Hard Reset Signaling or Cable Reset Signaling from the PHY Layer (see also Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 295 Figure 6.67 Hard/Cable Reset 6.12.2.4.1 PRL_HR_Reset_Layer state The PRL_HR_Reset_Layer State defines the mode of operation of both the Protocol Layer transmission and reception state machines during a Hard Reset or Cable Reset. During Hard Reset no USB Power Delivery Protocol Messages are sent or received; only Hard Reset Signaling is present after which the communication channel is assumed to have been disabled by the PHY Layer until completion of the Hard Reset. During Cable Reset no USB Power Delivery Protocol Messages are sent to or received by the Cable Plug but other USB Power Delivery communication May continue. The Protocol Layer Shall enter the PRL_HR_Reset_Layer state from any other state when:  A Hard Reset Request is received from the Policy Engine or  Hard Reset Signaling is received from the PHY Layer or Hard Reset request received from Policy Engine2 | Cable Reset request received from Policy Engine4 | Hard Reset signalling received By PHY Layer | Cable Reset signalling received By PHY Layer3 PHY Hard Reset request sent | PHY Cable Reset request sent Hard Reset complete from Policy Engine | Cable Reset complete from Policy Engine Physical Layer informed PRL_HR_Request_Hard_Reset Actions on entry: Request PHY to perform a Hard Reset or Cable Reset PRL_HR_Reset_Layer Actions on entry: Reset MessageIDCounter. Protocol Layer message transmission transitions to PRL_Tx_Wait_For_Message_Request state. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. Protocol Layer reset complete & (Hard Reset was Initiated by Policy Engine | Cable Reset was Initiated by Policy Engine) Policy Engine informed Protocol Layer reset complete & (Hard Reset was initiated by Port Partner | Cable Reset received by Cable Plug) PRL_HR_Indicate_Hard_Reset Actions on entry: Inform the Policy Engine of the Hard Reset or Cable Reset Exit from Hard Reset Policy Engine informed PRL_HR_PHY_Hard_Reset_Requested Actions on entry: Inform Policy Engine Hard Reset or Cable Reset request has been sent PRL_HR_Wait_For_PE_Hard_Reset_Complete Actions on entry: Wait for Hard Reset or Cable Reset complete indication from Policy Engine. PRL_HR_PE_Hard_Reset_Complete Actions on entry: Inform Physical Layer Hard Reset or Cable Reset is complete PRL_HR_Wait_For_PHY_Hard_Reset_Complete Actions on entry: Start HardResetCompleteTimer Wait for Hard Reset or Cable Reset complete indication from PHY Hard Reset complete from PHY | Cable Reset complete from PHY | HardResetCompleteTimer timeout1 1) If the HardResetCompleteTimer timeout occurs this means that the PHY is still waiting to send the Hard Reset due to a non-idle channel. This condition will be cleared once the PE Hard Reset is completed. 2) Cable Plugs do not generate Hard Reset signaling but are required to monitor for Hard Reset signaling between the Port Partners and respond by resetting. 3) Cable Reset signaling is only recognized by a Cable Plug. 4) Cable Reset signaling cannot be generated by Cable Plugs. Page 296 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Cable Reset Request is received from the Policy Engine or  Cable Reset Signaling is received from the PHY Layer. On entry to the PRL_HR_Reset_Layer state the Protocol Layer Shall reset the MessageIDCounter. It Shall also reset the states of the Protocol Layer transmission and reception state machines to their starting points. The Protocol Layer transmission state machine Shall transition to the PRL_Tx_Wait_for_Message_Request state. The Protocol Layer reception state machine Shall transition to the PRL_Rx_Wait_for_PHY_Message state. The Protocol Layer Shall transition to the PRL_HR_Request_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has originated from the Policy Engine or  The Cable Reset request has originated from the Policy Engine. The Protocol Layer Shall transition to the PRL_HR_Indicate_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has been passed up from the PHY Layer or  A Cable Reset request has been passed up from the PHY Layer (Cable Plug only). 6.12.2.4.2 PRL_HR_Indicate_Hard_Reset state On entry to the PRL_HR_Indicate_Hard_Reset state the Protocol Layer Shall indicate to the Policy Engine that either Hard Reset Signaling or Cable Reset Signaling has been received. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when:  The indication to the Policy Engine has been sent. 6.12.2.4.3 PRL_HR_Request_Hard_Reset state On entry to the PRL_HR_Request_Hard_Reset state the Protocol Layer Shall request the PHY Layer to send either Hard Reset Signaling or Cable Reset Signaling. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state when:  The PHY Layer Hard Reset Signaling request has been sent or  The PHY Layer Cable Reset Signaling request has been sent. 6.12.2.4.4 PRL_HR_Wait_for_PHY_Hard_Reset_Complete state In the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state the Protocol Layer Shall start the HardResetCompleteTimer and wait for the PHY Layer to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PHY_Hard_Reset_Requested state when:  A Hard Reset complete indication is received from the PHY Layer or  A Cable Reset complete indication is received from the PHY Layer or  The HardResetCompleteTimer times out. 6.12.2.4.5 PRL_HR_PHY_Hard_Reset_Requested state On entry to the PRL_HR_PHY_Hard_Reset_Requested state the Protocol Layer Shall inform the Policy Engine that the PHY Layer has been requested to perform a Hard Reset or Cable Reset. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 297  The Indication to the Policy Engine has been sent. 6.12.2.4.6 PRL_HR_Wait_for_PE_Hard_Reset_Complete state In the PRL_HR_Wait_for_PE_Hard_Reset_Complete state the Protocol Layer Shall wait for the Policy Engine to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PE_Hard_Reset_Complete state when:  A Hard Reset complete indication is received from the Policy Engine or  A Cable Reset complete indication is received from the Policy Engine. 6.12.2.4.7 PRL_HR_PE_Hard_Reset_Complete On entry to the PRL_HR_PE_Hard_Reset_Complete state the Protocol Layer Shall inform the PHY Layer that the Hard Reset or Cable Reset is complete. The Protocol Layer Shall exit from the Hard Reset and return to normal operation when:  The PHY Layer has been informed that the Hard Reset is complete so that it will re-enable the communications channel. If Hard Reset Signaling is still pending due to a non-Idle channel this Shall be cleared and not sent or  The PHY Layer has been informed that the Cable Reset is complete. Page 298 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.3 List of Protocol Layer States Table 6.75, "Protocol Layer States" lists the states used by the various state machines. Table 6.75 Protocol Layer States State Name Section Protocol Layer Message Transmission Common Protocol Layer Message Transmission PRL_Tx_PHY_Layer_Reset Section 6.12.2.2.1.1 PRL_Tx_Wait_for_Message_Request Section 6.12.2.2.1.2 PRL_Tx_Layer_Reset_for_Transmit Section 6.12.2.2.1.3 PRL_Tx_Construct_Message Section 6.12.2.2.1.4 PRL_Tx_Wait_for_PHY_Response Section 6.12.2.2.1.5 PRL_Tx_Match_MessageID Section 6.12.2.2.1.6 PRL_Tx_Message_Sent Section 6.12.2.2.1.7 PRL_Tx_Check_RetryCounter Section 6.12.2.2.1.8 PRL_Tx_Transmission_Error Section 6.12.2.2.1.9 PRL_Tx_Discard_Message Section 6.12.2.2.1.10 Source Protocol Layer Message Transmission PRL_Tx_Src_Sink_Tx Section 6.12.2.2.2.1 PRL_Tx_Src_Source_Tx Section 6.12.2.2.2.2 PRL_Tx_Src_Pending Section 6.12.2.2.2.3 Sink Protocol Layer Message Transmission PRL_Tx_Snk_Start_of_AMS Section 6.12.2.2.3.1 PRL_Tx_Snk_Pending Section 6.12.2.2.3.2 Protocol Layer Message Reception PRL_Rx_Wait_for_PHY_Message Section 6.12.2.3.1 PRL_Rx_Layer_Reset_for_Receive Section 6.12.2.3.2 PRL_Rx_Send_GoodCRC Section 6.12.2.3.3 PRL_Rx_Check_MessageID Section 6.12.2.3.4 PRL_Rx_Store_MessageID Section 6.12.2.3.5 Hard Reset Operation PRL_HR_Reset_Layer Section 6.12.2.4.1 PRL_HR_Indicate_Hard_Reset Section 6.12.2.4.2 PRL_HR_Request_Hard_Reset Section 6.12.2.4.3 PRL_HR_Wait_for_PHY_Hard_Reset_Complete Section 6.12.2.4.4 PRL_HR_PHY_Hard_Reset_Requested Section 6.12.2.4.5 PRL_HR_Wait_for_PE_Hard_Reset_Complete Section 6.12.2.4.6 PRL_HR_PE_Hard_Reset_Complete Section 6.12.2.4.7 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 299 Chunking Chunked Rx RCH_Wait_For_Message_From_Protocol_Layer Section 6.12.2.2.1.1 RCH_Pass_Up_Message Section 6.12.2.2.1.1 RCH_Processing_Extended_Message Section 6.12.2.2.1.1 RCH_Requesting_Chunk Section 6.12.2.2.1.1 RCH_Waiting_Chunk Section 6.12.2.2.1.1 RCH_Report_Error Section 6.12.2.2.1.1 Chunked Tx TCH_Wait_For_Message_Request_From_Policy_Engine Section 6.12.2.1.3.1 TCH_Pass_Down_Message Section 6.12.2.1.3.2 TCH_Wait_For_Transmision_Complete Section 6.12.2.1.3.3 TCH_Message_Sent Section 6.12.2.1.3.4 TCH_Prepare_To_Send_Chunked_Message Section 6.12.2.1.3.5 TCH_Construct_Chunked_Message Section 6.12.2.1.3.6 TCH_Sending_Chunked_Message Section 6.12.2.1.3.7 TCH_Wait_Chunk_Request Section 6.12.2.1.3.8 TCH_Message_Received Section 6.12.2.1.3.9 TCH_Report_Error Section 6.12.2.1.3.10 Chunked Message Router RTR_Wait_for_Message_From_Protocol_Layer Section 6.12.2.1.4.1 RTR_Rx_Chunks Section 6.12.2.1.4.2 RTR_Tx_Chunks Section 6.12.2.1.4.3 Table 6.75 Protocol Layer States (Continued) State Name Section Page 300 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13 Message Applicability The following tables outline the Messages supported by a given Port, depending on its capability. When a Message is supported the feature and the AMS implied by the Message Shall also be supported. The abbreviations in Table 6.76, "Message Applicability Abbreviations" are used in this section to denote the level of support required. For the case of Conditional Normative a note has been added to indicate the condition. "CN/" notation is used to indicate the level of support when the condition is not present. "R/" and "O/" notation is used to indicate the response when the Recommended or Optional Message is not supported. Note: Where NS/R/NK is indicated for Received Messages this Shall apply to the PE_CBL_Ready, PE_SNK_Ready or PE_SRC_Ready states only since unexpected Messages received during an AMS are Pro- tocol Errors (see Section 6.8.1, "Soft Reset and Protocol Error"). This section covers Control Message and Data Message support for Sources, Sink and Cable Plugs. It also covers VDM Command support for DFPs, UFPs and Cable Plugs. Table 6.76 Message Applicability Abbreviations Abbreviation Meaning Description N Normative Shall be supported by this Port/Cable Plug. CN Conditional Normative Shall supported by a given Port/Cable Plug based on features. R Recommended Should be supported by this Port/Cable Plug. O Optional May be supported by this Port/Cable Plug. NS Not Supported Shall result in a Not_Supported Message response by this Port/Cable Plug when received. I Ignore Shall be Ignored by this Port/Cable Plug when received. NK NAK This Port/Cable Plug Shall return Responder NAK to this Command when received. NA Not allowed Shall Not be transmitted by this Port/Cable Plug. DR Don’t Recognize There Shall be no response at all (i.e., not even a GoodCRC Message) from this Port/Cable Plug when received. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 301 6.13.1 Applicability of Control Messages Table 6.77, "Applicability of Control Messages" details Control Messages that Shall/Should/Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.77 Applicability of Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 Transmitted Message Accept N N N N Data_Reset CN10/R CN10/R NA NA DR_Swap O O N NA NA FR_Swap NA NA R NA NA Get_Country_Codes CN7/NA CN7/NA NA NA Get_PPS_Status NA CN6 NA NA Get_Sink_Cap R NA N NA NA Get_Sink_Cap_Extended R NA R NA NA Get_Source_Cap NA R N NA NA Get_Source_Cap_Extended NA R R NA NA Get_Source_Info NA R R NA NA Get_Revision R R NA NA Get_Status R R NA NA GoodCRC N N N N GotoMin (Deprecated) NA NA NA NA Not_Supported N N NA NA Ping (Deprecated) NA NA NA NA PR_Swap NA NA N NA NA PS_RDY N CN1/NA N NA NA Reject N O O O CN10/NA NA Soft_Reset N N NA NA VCONN_Swap R R NA NA Wait O NA O O NA NA 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Page 302 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Received Message Accept N N N N I I Data_Reset CN10/R CN10/R I I DR_Swap O/NS O/NS N I I FR_Swap NS NS CN4/NS I I Get_Country_Codes CN7/NS CN7/NS I I Get_PPS_Status CN6/NS NS I I Get_Sink_Cap NS N N I I Get_Sink_Cap_Extended NS N N I I Get_Source_Cap N NS N I I Get_Source_Cap_Extended CN2/NS NS CN2/NS I I Get_Source_Info CN11 NS N I I Get_Revision N N O/I O/I Get_Status CN3/NS CN3/NS CN3/NS CN8/I I GoodCRC N N N N GotoMin (Deprecated) NS NS I I Not_Supported N N CN8/I I Ping (Deprecated) NS NS/I I I PR_Swap NS NS N I I PS_RDY CN1/NS N N I I Reject CN5/NS N N N I I Soft_Reset N N N N VCONN_Swap CN1/ NS CN1/ NS I I Wait CN5/NS N N N I I Table 6.77 Applicability of Control Messages (Continued) Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 303 6.13.2 Applicability of Data Messages Table 6.78, "Applicability of Data Messages" details Data Messages (except for VDM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.78 Applicability of Data Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 Transmitted Message Source_Capabilities N NA N NA NA NA Request NA N NA NA NA Get_Country_Info CN5/O CN5/O NA NA NA BIST N1 N1 NA NA NA Sink_Capabilities NA N N NA NA NA Battery_Status CN2 CN2 NA NA NA Alert CN11/R CN11/R NA NA NA Enter_USB CN7/O CN7/O NA NA NA EPR_Request NA CN9 NA NA NA EPR_Mode CN9 CN9 NA NA NA Source_Info CN10 NA N NA NA NA Revision N N CN12/O/I NA O Received Message Source_Capabilities NS N N I I I Request N NS I I I Get_Country_Info CN5/NS CN5/NS I I I BIST N1 N1 N1 N1 N1 Sink_Capabilities CN4 NS CN4 I I I Battery_Status CN3/NS CN3/NS I I I Alert R/NS R/NS I I I Enter_USB CN7/O CN7/O CN8/I CN8/I I 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Page 304 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 EPR_Request CN9 NA I I I EPR_Mode CN9 CN9 I I I Source_Info NA N N I I I Revision N N I I I Table 6.78 Applicability of Data Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 305 6.13.3 Applicability of Extended Messages Table 6.79, "Applicability of Extended Messages" details Extended Messages (except for VDEM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual- Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.79 Applicability of Extended Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 Transmitted Message Battery_Capabilities CN1/NA CN1/NA NA NA NA Country_Codes CN10/NA CN10/NA NA NA NA Country_Info CN10/NA CN10/NA NA NA NA EPR_Source_Capabilities CN14/NA NA CN14/NA NA NA NA EPR_Sink_Capabilities NA CN14/NA CN14/NA NA NA NA Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NA CN7/NA NA NA NA Firmware_Update_Response CN7/NA CN7/NA CN7/NA O NA Get_Battery_Cap R R NA NA NA Get_Battery_Status R R NA NA NA Get_Manufacturer_Info R R NA NA NA Manufacturer_Info R R R NA NA PPS_Status CN8/NA NA NA NA NA Security_Request CN6/NA CN6/NA NA NA NA Security_Response CN6/NA CN6/NA CN6/NA NA NA Sink_Capabilities_Extended NA N N NA NA NA Source_Capabilities_Extended R NA R NA NA NA 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 306 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Status CN15/R CN15/R CN15/R CN12/NA CN12/NA NA Vendor_Defined_Extended O O O O O Received Message Battery_Capabilities CN4/NS CN4/NS I I I Country_Codes CN10/NS CN10/NS I I I Country_Info CN10/NS CN10/NS I I I EPR_Source_Capabilities NS CN14/NS CN14/NS I I I EPR_Sink_Capabilities CN14/NS NS CN14/NS I I I Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NS CN7/NS CN7/I O I Firmware_Update_Response CN7/NS CN7/NS I I I Get_Battery_Cap CN1/NS CN1/NS I I I Get_Battery_Status CN1/NS CN1/NS I I I Get_Manufacturer_Info R/NS R/NS R/I I I Manufacturer_Info CN5/NS CN5/NS I I I PPS_Status NS CN9/NS I I I Security_Request CN6/NS CN6/NS CN6/I I I Security_Response CN6/NS CN6/NS I I I Sink_Capabilities_Extended CN11/NS NS CN11/NS I I I Source_Capabilities_Extended NS CN2/NS CN2/NS I I I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 307 Status CN33/NS CN3/NS I I I Vendor_Defined_Extended O/NS O/NS O/I O/I O/I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 308 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.4 Applicability of Extended Control Messages Table 6.80, "Applicability of Extended Control Messages" details Extended Control Messages that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.80 Applicability of Extended Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD2 Transmitted Message EPR_Get_Source_Cap NA CN1 CN1 NA NA EPR_Get_Sink_Cap CN1 NA CN1 NA NA EPR_KeepAlive NA CN1 NA NA EPR_KeepAlive_Ack CN1 NA NA NA Received Message EPR_Get_Source_Cap CN1 NS CN1 I I EPR_Get_Sink_Cap NS CN1 CN1 I I EPR_KeepAlive CN1 NS I I EPR_KeepAlive_Ack NS CN1 I I 1) Shall be supported by products that support EPR Mode. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 309 6.13.5 Applicability of Structured VDM Commands Table 6.81, "Applicability of Structured VDM Commands" details Structured VDM Commands that Shall/Should/ Shall Not be transmitted and received by a DFP, UFP, Cable Plug or VPD. If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. Table 6.81 Applicability of Structured VDM Commands Command Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD4 Transmitted Command Request Discover Identity CN1,6/R R2 NA NA NA Discover SVIDs CN1/O O NA NA NA Discover Modes CN1/O O NA NA NA Enter Mode CN1/NA NA NA NA NA Exit Mode CN1/NA NA NA NA NA Attention O O NA NA NA Received Command Request/Transmitted Command Response Discover Identity CN5,6/R/ NK3 CN1,6/R/ NK3 N I N Discover SVIDs O/NK3 CN1/NK3 CN1/NK I NK Discover Modes O/NK3 CN1/NK3 CN1/NK I NK Enter Mode NK3 CN1/NK3 CN1/NK O NK Exit Mode NK3 CN1/NK3 CN1/NK O NK Attention O/I3 O/I3 I I I 1) Shall be supported when Modal Operation is supported. 2) May be transmitted by a UFP/Source during discovery (see Section 6.4.4.3.1, "Discover Identity" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 3) If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. 4) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT- VPD Shall only take place when not Connected to a Charger. 5) Shall be supported by products with more than one DFP. 6) Shall be supported by products that support [USB4]. Page 310 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.6 Applicability of Reset Signaling Table 6.82, "Applicability of Reset Signaling" details the Reset that Shall/Should/ Shall Not be transmitted and received by a DFP/UFP or Cable Plug. 6.13.7 Applicability of Fast Role Swap Request Table 6.83, "Applicability of Fast Role Swap Request" details the Fast Role Swap Request that Shall/Should/ Shall Not be transmitted and received by a Source or Sink. Table 6.82 Applicability of Reset Signaling Reset Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD2 Transmitted Message/Signaling Soft_Reset N N NA NA NA Hard Reset N N NA NA NA Cable Reset CN1 NA NA NA NA Received Message/Signaling Soft_Reset N N N N N Hard Reset N N N N N Cable Reset DR DR N N N 1) Shall be supported when transmission of SOP’ Packets are supported, and the Port can supply VCONN. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Table 6.83 Applicability of Fast Role Swap Request Command Type Source Sink Dual-Role Power Transmitted Message/Signaling Fast Role Swap NA NA R Received Message/Signaling Fast Role Swap NA NA R Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 311 6.14 Value Parameters Table 6.84, "Value Parameters" contains value parameters used in this section. Table 6.84 Value Parameters Parameter Description Value Unit Reference MaxExtendedMsgLen Maximum length of an Extended Message as expressed in the Data Size field. 260 Byte Section 6.2.1.2 MaxExtendedMsgChunkLen Maximum length of an Extended Message Chunk. 26 Byte Section 6.2.1.2 MaxExtendedMsgLegacyLen Maximum length of an Extended Message that can be sent without Chunking. 26 Byte Section 6.2.1.2 Page 312 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7 Power Supply 7.1 Source Requirements 7.1.1 Behavioral Aspects A PDUSB Source exhibits the following behaviors:  Shall supply [USB Type-C 2.4] USB Type-C® current to VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS voltage transitions as bound by undershoot, overshoot and transition time requirements. 7.1.2 Source Bulk Capacitance The Source bulk capacitance Shall Not be placed between the transceiver isolation impedance and the USB receptacle. The Source bulk capacitance consists of C1 and C2 as shown in Figure 7.1, "Placement of Source Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect might also be part of the circuit implemented by the Source to limit its VBUS Output Voltage Limit (OVL) as described in Section 7.1.7.5, "Output Voltage Limit". Though a Source Shall limit its output voltage, a Sink Shall implement Sink OVP as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. If the power supply is shared across multiple ports, the bulk capacitance is defined as cSrcBulkShared. If the power supply is dedicated to a single Port, the minimum bulk capacitance is defined as cSrcBulk. The Source bulk capacitance is allowed to change for a newly Negotiated power level. The capacitance change Shall occur before the Source is ready to operate at the new power level. During a Power Role Swap, the Initial Source Shall transition to Swap Standby before operating as the New Sink. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.1 Placement of Source Bulk Capacitance 7.1.3 Types of Sources Consistent with the Power Data Objects discussed in Section 6.4.1, "Capabilities Message", the power supply types that are available as Sources in a USB Power Delivery System are:  The Fixed Supply PDO exposes well-regulated fixed voltage power supplies. Sources Shall support at least one Fixed Supply capable of supplying vSafe5V. The output voltage of a Fixed Supply Shall remain C2 Ohmic Interconnect GND SHIELD VBUS ... Data Lines GND SHIELD VBUS ... Data Lines SOURCE CABLE C1 Power Supply Source Bulk Capacitance OVL Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 313 within the range defined by the relative tolerance vSrcNew and the absolute band vSrcValid as listed in Table 7.23, "Source Electrical Parameters" and described in Section 7.1.8, "Output Voltage Tolerance and Range".  The Variable Supply (non-Battery) PDO exposes less well-regulated Sources. The output voltage of a Variable Supply (non-Battery) Shall remain within the absolute maximum output voltage and the absolute minimum output voltage exposed in the Variable Supply PDO.  The Battery Supply PDO exposes Batteries than can be connected directly as a Source to VBUS. The output voltage of a Battery Supply Shall remain within the absolute maximum output voltage and the absolute minimum output exposed in the Battery Supply PDO.  The Programmable Power Supply (PPS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the Programmable Power Supply Shall remain within a range defined by the relative tolerance vPpsNew and the absolute band vPpsValid.  The Adjustable Voltage Supply (AVS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the AVS Shall remain within a range defined by the relative tolerance vAvsNew and the absolute band vAvsValid. 7.1.4 Source Transitions 7.1.4.1 Fixed Supply 7.1.4.1.1 Fixed Supply Positive Voltage Transitions The Source Shall transition VBUS from the starting voltage to the higher new voltage in a controlled manner. The Negotiated new voltage (e.g., 5V, 9V, 15V, …) defines the nominal value for vSrcNew. During the positive transition the Source Should be able to supply the Sink Standby current and the transient current to charge the total bulk capacitance on VBUS. The slew rate of the positive transition Shall Not exceed vSrcSlewPos. The transitioning Source output voltage Shall settle within vSrcNew by tSrcSettle. The Source Shall be able to supply the Negotiated power level at the new voltage by tSrcReady. The positive voltage transition Shall remain above vSrcValid min of the previous Explicit Contract and below vSrcValid max of the new Explicit Contract (Figure 7.2, "Transition Envelope for Positive Voltage Transitions"). The voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.2, "Transition Envelope for Positive Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.2 Transition Envelope for Positive Voltage Transitions At the start of the positive voltage transition the VBUS voltage level Shall Not droop vSrcValid min below either vSrcNew (i.e., if the starting VBUS voltage level is not vSafe5V) or vSafe5V as applicable. Starting voltage vSrcNew(typ) t0 vSrcSlewPos tSrcSettle vSrcValid(max) Upper bound of valid Source range vSrcNew(max) vSrcNew(min) tSrcReady Lower bound of valid Source range § § vSrcValid(min) beyond min/max limits of starting voltage Page 314 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewPos limit. 7.1.4.1.2 Fixed Supply Negative Voltage Transitions Negative voltage transitions are defined as shown in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" and are specified in a similar manner to positive voltage transitions. Figure 7.3, "Transition Envelope for Negative Voltage Transitions" does not apply to vSafe0V transitions. The slew rate of the negative transition Shall Not exceed vSrcSlewNeg. The negative voltage transition Shall remain below vSrcValid max of the previous Explicit Contract and above vSrcValid min of the new Explicit Contract, as shown in FFigure 7.3, "Transition Envelope for Negative Voltage Transitions". The transitioning Source output voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.3 Transition Envelope for Negative Voltage Transitions If the newly Negotiated voltage is vSafe5V, then the vSrcValid limits Shall determine the transition window and the transitioning Source Shall settle within the vSafe5V limits by tSrcSettle. Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewNeg limit. 7.1.4.2 SPR Programmable Power Supply (PPS) 7.1.4.2.1 SPR Programmable Power Supply Voltage Transitions The Programmable Power Supply (PPS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the Programmable RDO defines the nominal value of the PPS output voltage after completing a voltage change and Shall settle within the limits defined by vPpsNew by tPpsSrcTransSmall for steps smaller than or equal to vPpsSmallStep, or else, within the limits defined by vPpsNew by tPpsSrcTransLarge, but only in case the Programmable Power Supply is not in CL mode. Any overshoot beyond vPpsNew Shall Not exceed vPpsValid at any time. Any undershoot beyond vPpsNew Shall Not exceed vPpsValid for currents not resulting in CL mode. The PPS output voltage May change in a step-wise or linear manner and the slew rate of either type of change Shall Not exceed vPpsSlewPos for voltage increases or vPpsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the PPS output voltage is defined as vPpsStep. A PPS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level. All PPS voltage increases Shall Starting voltage Lower bound of valid Source range Upper bound of valid Source range t0 tSrcSettle tSrcReady vSrcNew(typ) vSrcValid(min) vSrcNew(max) vSrcNew(min) § vSrcSlewNeg § vSrcValid(max) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 315 result in a voltage that is greater than or equal to the previous PPS output voltage. Likewise, all PPS voltage decreases Shall result in a voltage that is less than or equal to the previous PPS output voltage. Since a Sink can draw current up to the Negotiated APDO current level in case of a voltage step, the voltage might not increase to the requested level due to the power supply operating in CL mode. Likewise, since a Sink can have a Battery connected to VBUS, the voltage might not decrease to the requested level due to the Battery voltage being higher than the output voltage set point the Source is transitioning to. Were the Source to rely on checking the voltage on VBUS, in either case, to determine when its power supply is ready a PS_RDY Message would never be sent. When the PPS voltage steps up or down, a PS_RDY Message Shall be sent within:  tPpsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vPpsSmallStep.  tPpsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vPpsSmallStep provided that either the voltage on VBUS has reached vPpsNew or the power supply is in CL mode. When vPpsNew is lower than the Battery voltage, or the Source's primary power is cut off the Sink Shall immediately disconnect its Battery from VBUS. In these situations, the output current could reverse polarity and the Sink is not allowed to source current (see Section 7.2.1, "Behavioral Aspects" and Section 7.2.9, "Robust Sink Operation"). Figure 7.4, "PPS Positive Voltage Transitions" and Figure 7.5, "PPS Negative Voltage Transitions" below show the output voltage behavior of a Programmable Power Supply in response to positive and negative voltage change requests. The parameters vPpsMinVoltage and vPpsMaxVoltage define the lower and upper limits of the PPS range respectively (see Table 10.11, "SPR Programmable Power Supply Voltage Ranges" for required ranges). vPpsMinVoltage corresponds to the Minimum Voltage field in the PPS APDO and vPpsMaxVoltage corresponds to Maximum Voltage field in the PPS APDO. If the Sink negotiates for a new PPS APDO, then the transition between the two PPS APDOs Shall occur as described in Section 7.3.1, "Transitions caused by a Request Message". Figure 7.4 PPS Positive Voltage Transitions vPpsMinVoltage V(2) = 1 + vPpsMinVoltage vPpsMinVoltage V(1) § § Programmable Power Supply Output Range § vPpsSlewPos V(3) = 1+n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § vPpsSlewPos vPpsSlewPos § § § § vPpsValid vPpsNew § § vPpsValid vPpsValid vPpsNew § § vPpsValid Nominal V(2) Nominal V(3) vPpsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) Page 316 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.5 PPS Negative Voltage Transitions Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vPpsSlewNeg and vPpsSlewPos limits. See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage and current DNL step adjustments. 7.1.4.2.2 SPR Programmable Power Supply Current Limit The Programmable Power Supply operating in SPR PPS Mode Shall limit its output current to the Operating Current field value in the RDO when the Sink attempts to draw more current than the Operating Current field value level. The programming step size for the Operating Current is iPpsCLStep. All programming changes of the Operating Current Shall settle to the new Operating Current field value within tPpsCLProgramSettle. The SPR PPS Operating Current regulation accuracy during Current Limit is defined as iPpsCLNew. The minimum programmable Current Limit level is iPpsCLMin. A Source that supports SPR PPS Mode Shall support Current Limit programmability between iPpsCLMin and the Maximum Current value in the SPR PPS APDO. A Source which receives a request for current below iPpsCLMin Should reject the request. A Source that accepts a request for current below iPpsCLMin Shall set its current limit at 1A. The response of an SPR PPS to a load change depends on the Operating mode of the SPR PPS and the magnitude of the load change. These dependencies lead to one of four possible responses of an SPR PPS to any load change. They are differentiated by the value of the PPS Status OMF before and after the load change:  If the PPS Status OMF is cleared both before and after the load change, the SPR PPS responds solely by maintaining the output voltage. The SPR PPS output voltage Shall remain within vPpsValid range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsTransient. The Operating Mode Flag Shall remain cleared during the load change response of the SPR PPS.  If the PPS Status OMF is cleared before the load change and set after the load change, the SPR PPS responds by reducing its output voltage to limit the SPR PPS output current. The SPR PPS output current Shall stay within the iPpsCVCLTransient range once it reaches the iPpsCVCLTransient range. The SPR vPpsMinVoltage V(c) = 1 + vPpsMinVoltage vPpsMinVoltage V(d) § § Programmable Power Supply Output Range § V(b) = 1 + n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § § § § vPpsValid vPpsNew § § vPpsValid Nominal V(c) Nominal V(b) vPpsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vPpsValid vPpsNew § § vPpsValid § vPpsSlewNeg vPpsSlewNeg vPpsSlewNeg Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 317 PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCVCLTransient. The Operating Mode Flag Shall be set when the SPR PPS load change response settles.  If the PPS Status OMF is set both before and after the load change, the SPR PPS responds by adjusting its output voltage to maintain the output current. The SPR PPS output current Shall stay within the iPpsCLTransient range. The SPR PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCLSettle. The Operating Mode Flag Shall remain set during the load change response of the SPR PPS.  If the PPS Status OMF is set before the load change and cleared after the load change, the PPS responds to the load change by increasing its output voltage to vPpsNew and then maintaining it. The SPR PPS output voltage Shall stay within the vPpsCLCVTransient range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsCLCVTransient. The Operating Mode Flag Shall be cleared when the PPS load change response settles. The SPR PPS Source Shall maintain its output voltage at the value requested in the PPS RDO for all static and dynamic load conditions except when in Current Limit operation. In response to any static or dynamic load condition during Current Limit operation that causes the SPR PPS output voltage to drop below vPpsShutdown the Source May send Hard Reset Signaling and Shall discharge VBUS to vSafe0V then resumes USB Default Operation at vSafe5V. When the Sink attempts to draw more current than the Operating Current in the RDO, the Source Shall limit its output current. The current available from the Source during Current Limit mode Shall meet iPpsCLNew. The Sink May Not reduce its Operating Current request in the RDO when the PPS Status OMF is set. Current limiting Shall be performed by the SPR PPS Source. Sinks that rely on PPS Current Limiting Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The Source Shall Not shutdown or otherwise disrupt the available output power while in Current Limit mode unless another protection mechanism as outlined in Section 7.1.7, "Robust Source Operation" is engaged to protect the Source from damage. An SPR PPS Source that is operating in Current Limit Shall Not change its set-point in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The relationship between SPR PPS programmable output voltage and SPR PPS programmable Current Limit Shall be as shown in Figure 7.6, "SPR PPS Programmable Voltage and Current Limit". The transition between the Constant Voltage mode and the Current Limit mode occurs between points a and b. The PPS Status OMF Shall be set or cleared within this region. In Current Limit mode when the load resistance changes, the output current of the Source Shall stay within iPpsCLNew. The proper behavior is represented by point c. Page 318 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.6 SPR PPS Programmable Voltage and Current Limit 7.1.4.2.3 SPR PPS Constant Power Mode In Constant Power mode (when the PPS Power Limited bit is set) the Source May supply power that exceeds the Source's PDP Rating. Sinks May limit their Operating Current request in the RDO and Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The tolerances along the Constant Power Curve Shall Not extend into the Guaranteed Capability Area of Figure 7.7, "SPR PPS Constant Power". Current Voltage PPS APDO Min Voltage (max) PPS APDO Max Voltage iPpsCLMin PPS APDO Max Current vPpsNew PPS RDO Operating Current PPS RDO Output Voltage Programmable Voltage Only Region Programmable Voltage & Programmable Current Limit Region Valid Current Limit Response Invalid Current Limit Response iPpsCLNew a Current Limit Flag set Current Limit Flag cleared b c c c Source Disconnect Region vPpsShutdown (min) Point a represents entry into the transition region between Constant Voltage mode and Current Limit mode. Point b represents exit from the transition region between Constant Voltage mode and Current Limit mode. Point c represents the exit from the iPpsCLNew region as the voltage drops below the PPS APDO Min Voltage. The Source May disconnect at any point inside the tolerance range of the minimum voltage defined in the PPS APDO. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 319 Figure 7.7 SPR PPS Constant Power Current Voltage Nominal limits as pr. the APDO Guaranteed operating capability as pr. the APDO Tolerance area for actual voltages (only static tolerances are shown) vPpsNew PDP constant power curve Max APDO Voltage Capabilities when the Power Limited bit is set The figure shows only the steady state after the transition vPpsNew 0A 0V iPpsCLNew (X = PPS APDO Max Current, Y = Prog Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • Prog Voltage = 9V • PPS APDO Max Current = 3 A Coordinate = (3, 9) vPpsNew Min APDO Voltage vPpsNew iPpsCLMin(1A) Min Current Limit PPS APDO Max Current Valid Current Limit Range (X = PDP/PPS APDO Max Current, Y = PPS APDO Max Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • PPS APDO Max Voltage = 11 V Coordinate = (2.45, 11) Page 320 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3 Adjustable Voltage Supply (AVS) 7.1.4.3.1 Adjustable Voltage Supply Voltage Transitions The Adjustable Voltage Supply (AVS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the AVS RDO defines the nominal value of the AVS output voltage after completing a voltage change and Shall settle within the limits defined by vAvsNew by tAvsSrcTransSmall for steps smaller than or equal to vAvsSmallStep, or else, within the limits defined by vAvsNew by tAvsSrcTransLarge for steps larger than vAvsSmallStep. Any overshoot beyond vAvsNew Shall Not exceed vAvsValid at any time. Any undershoot beyond vAvsNew Shall Not exceed vAvsValid at any time. The AVS output voltage May change in a stepwise or linear manner and the slew rate of either type of change Shall Not exceed vAvsSlewPos for voltage increases or vAvsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the AVS output voltage is defined as vAvsStep. An AVS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level if the change of output voltage is less than or equal to vAvsSmallStep relative to vAvsNew. All AVS voltage increases Shall result in a voltage that is greater than or equal to the previous AVS output voltage. Likewise, all AVS voltage decreases Shall result in a voltage that is less than or equal to the previous AVS output voltage. Any time the Source enters the AVS range of operation that voltage transition is considered a voltage step larger than vAvsSmallStep. When the AVS voltage steps up or down, a PS_RDY Message Shall be sent within:  tAvsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vAvsSmallStep.  tAvsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vAvsSmallStep provided the voltage on VBUS has reached vAvsNew. Figure 7.8, "AVS Positive Voltage Transitions" and Figure 7.9, "AVS Negative Voltage Transitions" below show the output voltage behavior of an AVS in response to positive and negative voltage change requests. The parameters vAvsMinVoltage and vAvsMaxVoltage define the lower and upper limits of the AVS range respectively:  For SPR AVS Sources there are two possible voltage ranges where the vAvsMinVoltage is always 9V and vAvsMaxVoltage is either 15V or 20V depending on the Source's PDP. See Table 10.9, "SPR Adjustable Voltage Supply (AVS) Voltage Ranges".  For EPR AVS Sources vAvsMinVoltage corresponds to Minimum Voltage field (always 15V) in the EPR AVS APDO and vAvsMaxVoltage corresponds to Maximum Voltage field in the EPR AVS APDO. See Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" for required ranges. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 321 Figure 7.8 AVS Positive Voltage Transitions Figure 7.9 AVS Negative Voltage Transitions See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage DNL step adjustments. vAvsMinVoltage V(2) = 1 + vAvsMinVoltage vAvsMinVoltage V(1) § § Adjustable Voltage Supply Output Range § vAvsSlewPos V(3) = 1+n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § vAvsSlewPos vAvsSlewPos § § § § vAvsValid vAvsNew § § vAvsValid vAvsValid vAvsNew § § vAvsValid Nominal V(2) Nominal V(3) vAvsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) vAvsMinVoltage V(c) = 1 + vAvsMinVoltage vAvsMinVoltage V(d) § § Adjustable Voltage Supply Output Range § V(b) = 1 + n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § § § § vAvsValid vAvsNew § § vAvsValid Nominal V(c) Nominal V(b) vAvsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vAvsValid vAvsNew § § vAvsValid § vAvsSlewNeg vAvsSlewNeg vAvsSlewNeg Page 322 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3.2 Adjustable Voltage Supply Current The AVS Shall maintain its output voltage at the value requested in the AVS RDO for all static and dynamic load conditions that do not exceed the Operating Current in the RDO. Unlike the SPR PPS programmable current, the AVS programmable power May range from zero to the PDP. The maximum operating current:  For SPR Sources, the maximum operating current is defined in the SPR Source_Capabilities Message Maximum Current 15V/Maximum Current 20V fields.  For EPR Sources, the maximum operating current has to be calculated as the lower of the PDP field value/Output Voltage or 5A whichever is lower. See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" 7.1.5 Response to Hard Resets Hard Reset Signaling indicates a communication failure has occurred and the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall drive VBUS to vSafe0V as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". The USB connection May reset during a Hard Reset since the VBUS voltage will be less than vSafe5V for an extended period of time. After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform to the VCONN timing as specified in [USB Type-C 2.4]. A Sink that enters Hard Reset can have cSnkBulkPd present until VBUS drops below vSafe0V. The Source Shall take this into consideration. Device operation during and after a Hard Reset is defined as follows:  Self-powered devices Should Not disconnect from USB during a Hard Reset (see Section 9.1.2, "Mapping to USB Device States").  Self-powered devices operating at more than vSafe5V May Not maintain full functionality after a Hard Reset.  Bus powered devices will disconnect from USB during a Hard Reset due to the loss of their power source. When a Hard Reset occurs the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall start to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. The Source Shall meet both tSafe5V and tSafe0V relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 323 Figure 7.10 Source VBUS and VCONN Response to Hard Reset VCONN will meet tVCONNDischarge relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset" due to the discharge circuitry in the Cable Plug. VCONN Shall meet tVCONNOn relative to VBUS reaching vSafe5V. Note: tVCONNOn and tVCONNDischarge are defined in [USB Type-C 2.4]. 7.1.6 Changing the Output Power Capability Some USB Power Delivery Negotiations will require the Source to adjust its output power capability without changing the output voltage. In this case the Source Shall be able to supply a higher or lower load current within tSrcReady. 7.1.7 Robust Source Operation 7.1.7.1 Output Over Current Protection Sources Shall implement over current protection to prevent damage from output current that exceeds the current handling capability of the Source. The definition of current handling capability is left to the discretion of the Source implementation and Shall take into consideration the current handling capability of the connector contacts. If the over current protection implementation does not use a Hard Reset or Error Recovery, it Shall Not interfere with the Negotiated VBUS current level. After three consecutive over current events Source Shall go to ErrorRecovery. Sources Should attempt to send Hard Reset Signaling when over current protection engages followed by an Alert Message indicating an OCP event once an Explicit Contract has been established. The over current protection response May engage at either the Port or system level. Systems or ports that have engaged over current protection Should attempt to resume USB Default Operation after determining that the cause of over current is no longer present and May latch off to protect the Port or system. The definition of how to detect if the cause of over current is still present is left to the discretion of the Source implementation. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over current event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over current protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over current. During the over current response and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. Old voltage 0V vSafe0V(max) vSrcNeg(max) t0 tSafe5V tSafe0V tSrcTurnOn vSafe5V(max), VCONN(max) § vVconnDischarge tVconnDischarge tVconnOn tSrcRecover Page 324 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.7.2 Over Temperature Protection Sources Shall implement Over Temperature Protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Source. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Source implementation. In order to avoid reaching an OTP event, Sources May proactively reduce the available power being offered to the Sink, even though these offers might be lower than the Source would be expected to offer during normal thermal operating conditions. Prior to reducing power, the Source Should generate Alert Message indicating an Operating Condition Change and set the Temperature Status bit in the SOP Status Message to Warning (10b). Sources Should attempt to send Hard Reset Signaling when OTP engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The OTP response May engage at either the Port or system level. Systems or ports that have engaged OTP Should attempt to resume USB Default Operation and May latch off to protect the Port or system. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over temperature event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. During the OTP and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. 7.1.7.3 vSafe5V Externally Applied to Ports Supplying vSafe5V Safe operation mandates that Power Delivery Sources Shall be tolerant of vSafe5V being present on VBUS when simultaneously applying power to VBUS. Normal USB PD communication Shall be supported when this vSafe5V to vSafe5V connection exists. 7.1.7.4 Detach A USB Detach is detected electrically using CC detection on the USB Type-C connector. When the Source is Detached the Source Shall transition to vSafe0V by tSafe0V relative to when the Detach event occurred. During the transition to vSafe0V the VBUS voltage Shall be below vSafe5V max by tSafe5V relative to when the Detach event occurred and Shall Not exceed vSafe5V max after this time. Sources operating in EPR Mode need to avoid creating large differential voltages at the connector. See Appendix H in the [USB Type-C 2.4] specification for background information. To achieve this, Sources operating in EPR Mode, upon detecting a disconnect, Shall stop sourcing current and minimize VBUS capacitance. There May continue to be current sourced from the Source bulk capacitance, but that Should also be minimized by disconnecting as much of the Source bulk capacitance as possible. For example, the Source can stop sourcing from the Power Supply and the C1 portion of the Source bulk capacitance in Figure 7.1, "Placement of Source Bulk Capacitance" by disabling the Ohmic Interconnect switch. The Source Should detect the disconnect, stop sourcing current, and minimize the VBUS capacitance as quickly as practical. If this is done after the CC contacts disconnect and before the VBUS contacts disconnect there is less risk of large differential voltages at the connector. Note: A USB-PD transmission by the Source during a disconnect event will delay disconnect detection by the Source. 7.1.7.5 Output Voltage Limit The output voltage of Sources Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid or vAvsNew, vAvsValid as determined by the Negotiated VBUS value. Sources Shall meet applicable safety and regulatory requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 325 7.1.8 Output Voltage Tolerance and Range After a voltage transition is complete (i.e., after tSrcReady) and during static load conditions the Source output voltage Shall remain within the vSrcNew or vSafe5V limits as applicable. The ranges defined by vSrcNew and vSafe5V account for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e., after tSrcReady) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vSrcValid. The amount of time the Source output voltage can be in the band between either vSrcNew or vSafe5V and vSrcValid Shall Not exceed tSrcTransient. Refer to Table 7.23, "Source Electrical Parameters" for the output voltage tolerance specifications. Figure 7.11, "Application of vSrcNew and vSrcValid limits after tSrcReady" illustrates the application of vSrcNew and vSrcValid after the voltage transition is complete. The vSrcNew and vSrcValid limits Shall Not apply to VBUS during the VBUS discharge and switchover that occurs during a Fast Role Swap as described in Section 7.1.13, "Fast Role Swap". Figure 7.11 Application of vSrcNew and vSrcValid limits after tSrcReady The Source output voltage Shall be measured at the connector receptacle. The stability of the Source Shall be tested in 25% load step increments from minimum load to maximum load and also from maximum load to minimum load. The transient behavior of the load current is defined in Section 7.2.6, "Transient Load Behavior". The time between each step Shall be sufficient to allow for the output voltage to settle between load steps. In some systems it might be necessary to design the Source to compensate for the voltage drop between the output stage of the power supply electronics and the receptacle contact. The determination of whether compensation is necessary is left to the discretion of the Source implementation. 7.1.8.1 AVS/PPS Output Voltage Ripple The AVS/PPS output voltage ripple is expected to exceed the magnitude of one or more LSB as show in the Figure 7.12, "Expected AVS/PPS Ripple Relative to an LSB". Sink Load I1 vSrcNew(typ) tSrcReady iLoadStepRate vSrcValid(max) vSrcValid(min) vSrcNew(max) vSrcNew(min) tSrcTransient window у tSrcTransient windows у у iLoadReleaseRate Sink Load I2 Page 326 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.12 Expected AVS/PPS Ripple Relative to an LSB 7.1.8.2 AVS/PPS DNL Errors and Output Voltage/Current Tolerance The PPS voltage and current discrete LSB steps have a DNL tolerance as shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode" below. In absolute terms the step size of the LSB for both voltage and current is defined by vPpsStep/vAvsStep for voltage and iPpsCLStep for current. Several examples of Valid LSB steps are shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode":  The upper end of the DNL error (+1 LSB) shows the case where one step is effectively skipped.  The lower end of the DNL error (-1 LSB) shows the case where the voltage or current set-point remained the same. The ideal scenario for the DNL error (=0) matches the typical step size for the voltage or current. The intent of DNL is to guarantee that changes to the voltage/current have the correct directionality, and that the maximum step size is clearly defined. Note: The Source Should avoid scenarios where multiple consecutive steps have errors close to the Maximum and Minimum DNL. time voltage +1 LSB +1 LSB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 327 Figure 7.13 Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode 7.1.8.3 Programmable Power Supply Output Voltage Tolerance and Range After a voltage transition of a Programmable Power Supply is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vPpsNew limits. The range defined by vPpsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vPpsValid. The amount of time the Source output voltage can be in the band between vPpsNew and vPpsValid Shall Not exceed tPpsTransient. 7.1.8.4 Adjustable Voltage Supply Output Voltage tolerance and Range After a voltage transition of an AVS is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vAvsNew limits. The range defined by vAvsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vAvsValid. The amount of time the Source output voltage can be in the band between vAvsNew and vAvsValid Shall Not exceed tAvsTransient. Code Voltage, Current 1 LSB DNL < 0 LSB Max DNL = 1 LSB vPpsNew,vAvsNew, iPpsNew (max) vPpsNew,vAvsNew, iPpsNew (min) vPpsNew,vAvsNew, iPpsNew DNL = -1 LSB Page 328 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.9 Charging and Discharging the Bulk Capacitance on VBUS The Source Shall charge and discharge the bulk capacitance on VBUS whenever the Source voltage is Negotiated to a different value. The charging or discharging occurs during the voltage transition and Shall Not interfere with the Source's ability to meet tSrcReady. 7.1.10 Swap Standby for Sources Sources and Sinks of a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Source after the Source power supply has discharged the bulk capacitance on VBUS to vSafe0V as part of the Power Role Swap transition. While in Swap Standby:  The Source Shall Not drive VBUS that is therefore expected to remain at vSafe0V.  Any discharge circuitry that was used to achieve vSafe0V Shall be removed from VBUS.  The Dual-Role Power Port Shall be configured as a Sink.  The USB connection Shall Not reset even though vSafe5V is no longer present on VBUS (see Section 9.1.2, "Mapping to USB Device States"). The PS_RDY Message associated with the Source being in Swap Standby Shall be sent after the VBUS drive is removed. The time for the Source to transition to Swap Standby Shall Not exceed tSrcSwapStdby. Upon entering Swap Standby, the Source has relinquished its Power Role as Source and is ready to become the New Sink. The transition time from Swap Standby to being the New Sink Shall be no more than tNewSnk. The New Sink May start using power after the new Source sends the PS_RDY Message. 7.1.11 Source Peak Current Operation A Source that has the Fixed Supply PDO or AVS APDO Peak Current bits set to 01b, 10b and 11b Shall be designed to support one of the overload Capabilities defined in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability" respectively. The overload conditions are bound in magnitude, duration and duty cycle as listed in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability". Sources are not required to support continuous overload operation. When overload conditions occur, the Source is allowed the range of vSrcPeak (instead of vSrcNew) relative to the nominal value (see Figure 7.14, "Source Peak Current Overload"). When the overload capability is exceeded, the Source is expected take whatever action is necessary to prevent electrical or thermal damage to the Source. The Source May send a new Source_Capabilities Message with the Fixed Supply PDO or AVS APDO Peak Current bits set to 00b to prohibit overload operation even if an overload capability was previously Negotiated with the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 329 Figure 7.14 Source Peak Current Overload 7.1.12 Source Capabilities Extended Parameters Implementers can choose to make available certain characteristics of a PDUSB Source as a set of Static and/or dynamic parameters to improve interoperability between external power sources and portable computing devices. The complete list of reportable Static parameters is described in full in Section 6.5.1, "Source_Capabilities_Extended Message" and listed in Figure 6.37, "Source_Capabilities_Extended Message". The subset of parameters listed below directly represent Source Capabilities and are described in the rest of this section.  Voltage Regulation.  Holdup Time.  Compliance.  Peak Current.  Source Inputs.  Batteries. 7.1.12.1 Voltage Regulation Field The power consumption of a device can change dynamically. The ability of the Source to regulate its voltage output might be important if the device is sensitive to fluctuations in voltage. The Voltage Regulation bit field is used to convey information about the Sources output regulation and tolerance to various load steps. 7.1.12.1.1 Load Step Slew Rate The default load step slew rate is established at 150mA/µs. A Source Shall meet the following requirements under the load step reported in the Source_Capabilities_Extended Message:  The Source Shall maintain VBUS regulation within the vSrcValid range.  The noise on the CC line Shall remain below vNoiseIdle and vNoiseActive. Sink Port Current Source Port Voltage vSrcNew(max)/ vSrcPeak(max) Nominal Voltage vSrcNew(min) vSrcPeak(min) IOC level as requested in the Operating Current field of an RDO % level with respect to IOC as advertised in the Peak Current field of Fixed Supply PDO Additional operating range for Fixed Supply that supports overload capability Operating range for supply that DOES NOT support overload capability Page 330 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Test conditions require a change in both positive and negative load steps from 1Hz to 5000Hz, up to the Advertised Load Step Magnitude of the full load output including from both 10 mA and 10% initial load. The Source Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks" under all load conditions. 7.1.12.1.2 Load Step Magnitude The default load step magnitude rate Shall be 25% of IoC. The Source May report higher capability tolerating a load step of 90% of IoC. 7.1.12.2 Holdup Time Field The Holdup Time field Shall return a numeric value of the number of milliseconds the output voltage stays in regulation upon a short interruption of the AC Supply. An AC Supplied Source Shall report its holdup time in this field. The holdup time is measured with the load at rated maximum, with the AC Supply at 115VAC rms and 60Hz (or at 230VAC rms and 50Hz for a Source that does not support 115VAC AC Supply). The reported time describes the minimum length of time from the last completed AC Supply input cycle (zero-degree phase angle) until when the output voltage decays below vSrcValid (min). Sources are recommended to support a minimum of 3ms and are preferred to support over 10 milliseconds holdup time (equivalent to a half cycle drop from the AC Supply). See Figure 7.15, "Holdup Time Measurement". Figure 7.15 Holdup Time Measurement 7.1.12.3 Compliance Field An SPR Source claiming LPS, PS1 or PS2 compliance (see [IEC 62368-1]) Shall report its Capabilities in the Compliance field. Since the SPR Source May have several potential output voltage and current settings, every SPR Source supply (each indicated by a PDO) Shall be compliant to LPS requirements. Note: According to the requirements of [IEC 60950-1] and/or [IEC 62368-3], a device tested and certified with an LPS Source (SPR Source or EPR Source operating in SPR Mode) is prohibited from using a non-LPS Source (EPR Source operating in EPR Mode). Alternatively, [IEC 62368-1], classifies power sources according to their maximum, constrained power output (15watts or 100watts). 7.1.12.4 Peak Current The Source reports its ability to source peak current delivery in excess of the Negotiated amount in the Peak Current field. The duration of peak current Shall be followed by a current consumption below the Operating Current (IoC) in order to maintain average power delivery below the IoC current. vSrcValid(min) Hold Up Time у VBUS AC mains voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 331 A Source May have greater capability to source peak current than can be reported using the Peak Current field in the Fixed Supply PDO or AVS APDO. In this case the Source Shall report its additional capability in the Peak Current1/Peak Current2/Peak Current3 fields in the Source_Capabilities_Extended Message. Each overload period Shall be followed by a period of reduced current draw such that the rolling average current over the Overload Period field value with the specified Duty Cycle field value (see Section 6.5.1.10, "Peak Current Field") Shall Not exceed the Negotiated current. This is calculated as: Period of reduced current = (1 - value in Duty Cycle field/100) * value in Overload Period field 7.1.12.5 Source Inputs The Source Inputs field identifies the possible inputs that provide power to the Source. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. 7.1.12.6 Batteries The Number of Batteries/Battery Slots field Shall report the number of Batteries the Source supports. The Source Shall independently report the number of Hot Swappable Batteries and the number of Fixed Batteries. 7.1.13 Fast Role Swap A Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port supporting DRP as shown in Figure 7.16, "VBUS Power during Fast Role Swap". Figure 7.16 VBUS Power during Fast Role Swap When the power source connected to the Hub UFP stops sourcing power and VBUS at the Hub DRP connector discharges below vSrcValid(min), if VBUS has been Negotiated to a higher voltage than vSafe5V, or vSafe5V (min) the Fast Role Swap Request Shall be sent from the Hub DRP to the Host DRP and the Hub DRP Shall sink power. In the Fast Role Swap use case, the Hub DRP behaves like a bidirectional power path. The Hub DRP Shall Not enable VBUS discharge circuitry when changing operation from Initial Source to New Sink. The Hub DFP Port(s) Shall support default USB Type-C Current (see [USB Type-C 2.4]) until a new Explicit Contract is Negotiated. After sending the Fast Role Swap Request and while VBUS > vSafe5V (min), the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. The New Sink Shall Not draw more than iSnkStdby from VBUS until tSnkFRSwap after it has started sending the Fast Role Swap Request or VBUS has fallen below vSafe5V (min). The tSnkFRSwap time Shall start at the beginning of the Fast Role Swap Request or when VBUS falls below vSafe5V (min), whichever comes later. After waiting for tSnkFRSwap, the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. After the New Source has applied its Rp, the New Sink Shall be limited to USB Type-C Current (see [USB Type-C 2.4]) in an Implicit Contract until a new Explicit Contract is Negotiated. All Sink requirements Shall apply to the New Sink after the Fast Role Swap is complete. The Fast Role Swap response of the Host DRP is described in Section 7.2.10, "Fast Role Swap" since the Host DRP is operating as the Initial Sink prior to the Fast Role Swap. After the VBUS voltage level at the Hub DRP connector drops below vSafe5V a PS_RDY Message Shall be sent to the Host DRP as shown in the Fast Role Swap transition diagram of Section 7.3.4, "Transitions Caused by Fast Role Swap". USB PD Capable Hub DRP UFP DFP Power Source Bus Powered Accessory USB PD Capable Host DRP Power flow before the Fast Role Swap Power flow after the Fast Role Swap Page 332 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.17, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min)" and Figure 7.18, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min)" show the VBUS detection and timing for the New Source during a Fast Role Swap after the Fast Role Swap Request has been received. The New Source May turn on the VBUS output switch once VBUS is below vSafe5V (max). In this case, the New Source prevents VBUS from falling below vSafe5V (min). The new source Shall turn on the VBUS output switch within tSrcFRSwap of falling below vSafe5V (min). VBUS might have started at vSafe5V or at higher voltage. When the Fast Role Swap Request is detected, VBUS could therefore be either above vSafe5V (max), within the vSafe5V range, or below vSafe5V (min). If the Fast Role Swap Request is detected when VBUS is below vSafe5V (min), then the new source Shall turn on the VBUS output switch within tSrcFRSwap of detecting the Fast Role Swap Request. In this case, the maximum time from the beginning of the Fast Role Swap Request to VBUS being sourced May be tSrcFRSwap (max) + tFRSwapRx (max). Figure 7.17 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min) Figure 7.18 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min) 7.1.14 Non-application of VBUS Slew Rate Limits Scenarios where vSrcSlewPos and vPpsSlewPos VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When first applying VBUS after an Attach.  When applying VBUS as part of a Power Role Swap to Source Power Role.  When increasing VBUS from vSafe0V to vSafe5V during a Hard Reset.  During a Fast Role Swap when the Initial Sink applies VBUS. Old Voltage 0V vSafe5V(min) tSrcFRSwap vSafe5V(max) § New Source may turn on at any time after VBUS falls below vSafe5V(max) VBUS Old Source detects power loss and signals Fast Role Swap Old Voltage 0V vSafe5V(min) tSrcFRSwap VBUS is below vSafe5V(min) before FRS signal is finished Old Source detects power loss and signals Fast Role Swap tFRSwapRx (max) VBUS at new Source CC New Source may turn on after detecting Fast Role Swap signal Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 333 Scenarios where vSrcSlewNeg and vPpsSlewNeg VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When discharging VBUS to vSafe0V during a Hard Reset.  When discharging VBUS to vSafe0V as part of a Power Role Swap to Sink Power Role.  When discharging VBUS to vSafe0V after a Detach.  During a Fast Role Swap when the VBUS power source connected to the Hub UFP stops sourcing power. 7.1.15 VCONN Power Cycle 7.1.15.1 UFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the UFP is the VCONN Source, the following steps Shall be followed:  Following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message, the UFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type- C 2.4]) within tVCONNZero.  When VCONN is below vRaReconnect, the UFP Shall send a PS_RDY Message. Note: If the UFP was not sourcing VCONN, it still sends the PS_RDY Message.  The DFP Shall wait tVCONNReapplied following the last bit of the GoodCRC Message acknowledging the PS_RDY Message before sourcing VCONN. The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.19, "Data Reset UFP VCONN Power Cycle" below illustrates the UFP VCONN Power Cycle process. Figure 7.19 Data Reset UFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied PS_RDY (UFP) UFP DFP Page 334 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.15.2 DFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the DFP is the VCONN Source, the following steps Shall be followed: 1) If the DFP sent the Data_Reset Message and is sourcing VCONN then it Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero of the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 2) If the UFP sent the Data_Reset Message then the DFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 3) When VCONN is below vRaReconnect, the DFP Shall wait tVCONNReapplied before sourcing VCONN. 4) The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.20, "Data Reset DFP VCONN Power Cycle" below illustrates the DFP VCONN Power Cycle process. Figure 7.20 Data Reset DFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied UFP DFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 335 7.2 Sink Requirements 7.2.1 Behavioral Aspects A PDUSB Sink exhibits the following behaviors:  Shall Not draw more than [USB Type-C 2.4] USB Type-C Current from VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS in-rush current when increasing current consumption according to [USB 2.0] or [USB 3.2] as appropriate. 7.2.2 Sink Bulk Capacitance The Sink bulk capacitance consists of C3 and C4 as shown in Figure 7.21, "Placement of Sink Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect is expected to be part of an input Over Voltage Protection (Sink OVP) circuit implemented by the Sink as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. A Sink Shall implement OVP. The Sink Shall Not rely on the Source output voltage limit for its input OVP. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. An upper bound of cSnkBulkPd Shall Not be exceeded so that the transient charging, or discharging, of the total bulk capacitance on VBUS can be accounted for during voltage transitions. The Sink bulk capacitance that is within the cSnkBulk max or cSnkBulkPd max limits is allowed to change to support a newly Negotiated power level. The capacitance can be changed when the Sink enters Sink Standby or during a voltage transition or when the Sink begins to operate at the new power level. Changing the Sink bulk capacitance Shall Not cause a transient current on VBUS that violates the present Contract. During a Power Role Swap the Default Sink Shall transition to Swap Standby before operating as the New Source. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.21 Placement of Sink Bulk Capacitance 7.2.3 Sink Standby The Sink Shall transition to Sink Standby before a positive voltage transition of VBUS. During Sink Standby the Sink Shall reduce the current drawn to iSnkStdby. This allows the Source to manage the voltage transition as well as supply sufficient operating current to the Sink to maintain PD operation during the transition. The Sink Shall complete this transition to Sink Standby within tSnkStdby after evaluating the Accept Message from the Source. The transition when returning to Sink operation from Sink Standby Shall be completed within tSnkNewPower. The iSnkStdby requirement Shall only apply if the Sink current draw is higher than this level. See Section 7.3, "Transitions" for details. GND SHIELD VBUS ... Data Lines C3 GND SHIELD VBUS ... Data Lines SINK CABLE C4 Load Sink Bulk Capacitance Ohmic Interconnect OVP Page 336 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.3.1 Programmable Power Supply Sink Standby A Sink is not required to transition to Sink Standby when operating within the Negotiated PPS APDO. A Sink May consume the Operating Current value in the PPS RDO during PPS output voltage changes. However, prior to operating the SPR PPS in Current Limit, the Sink Shall program the PPS Operating Voltage to the lowest practical level that satisfies the Sink load requirement. Doing so will minimize the inrush current that occurs when the transition to Current Limit occurs. When operating with an SPR PPS Source that is in Current Limit, the Sink Shall Not change its load in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The load change magnitude Shall Not request a change to the Current Limit set-point that exceeds iPpsCLLoadStep. If the Sink Negotiates for a new PPS APDO, that is expected to increase VBUS voltage, then the Sink Shall transition to Sink Standby while changing between PPS APDOs as described in Section 7.3.1, "Transitions caused by a Request Message". 7.2.4 Suspend Power Consumption When Source has set its USB Suspend Supported flag (see Section 6.4.1.2.1.2, "USB Suspend Supported"), a Sink Shall go to the lowest power state during USB suspend. The lowest power state Shall be pSnkSusp or lower for a PDUSB Peripheral and pHubSusp or lower for a PDUSB Hub. There is no requirement for the Source voltage to be changed during USB suspend. 7.2.5 Zero Negotiated Current When a Sink Requests zero current as part of a power Negotiation with a Source, the Sink Shall go to the lowest power state, pSnkSusp or lower, where it can still communicate using PD signaling. 7.2.6 Transient Load Behavior When a Sink's operating current changes due to a load step, load release or any other change in load level, the positive or negative overshoot of the new load current Shall Not exceed the range defined by iOvershoot. For the purposes of measuring iOvershoot the new load current value is defined as the average steady state value of the load current after the load step has settled. The rate of change of any shift in Sink load current during normal operation Shall Not exceed iLoadStepRate (for load steps) and iLoadReleaseRate (for load releases) as measured at the Sink receptacle. The Sink's operating current Shall Not change faster than the value reported in the Source's Load Step Slew Rate in its Voltage Regulation bit field and Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks". 7.2.7 Swap Standby for Sinks The Sink functionality in a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Sink after evaluating the Accept Message from the Source during a Power Role Swap. While in Swap Standby the Sink's current draw Shall Not exceed iSnkSwapStdby from VBUS and the Dual-Role Power Port Shall be configured as a Source after VBUS has been discharged to vSafe0V by the existing Initial Source. The Sink's USB connection Should Not be reset even though vSafe5V is not present on the VBUS conductor (see Section 9.1.2, "Mapping to USB Device States"). The time for the Sink to transition to Swap Standby Shall be no more than tSnkSwapStdby. When in Swap Standby the Sink has relinquished its Power Role as Sink and will prepare to become the New Source. The transition time from Swap Standby to New Source Shall be no more than tNewSrc. 7.2.8 Sink Peak Current Operation Sinks Shall only make use of a Source overload capability when the corresponding Fixed Supply PDO Peak Current (see Section 6.4.1.2.1.8, "Peak Current") or AVS APDO Peak Current (see Section 6.4.1.2.4.3.2, "Peak Current") bits are set to 01b, 10b and 11b. Sinks Shall manage thermal aspects of the overload event by not exceeding the average Negotiated output of a Fixed Supply or AVS that supports Peak Current operation. Sinks that depend on the Peak Current capability for enhanced system performance Shall also function correctly when Attached to a Source that does not offer the Peak Current capability or when the Peak Current capability has been inhibited by the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 337 7.2.9 Robust Sink Operation 7.2.9.1 Sink Bulk Capacitance Discharge at Detach When a Source is Detached from a Sink, the Sink Shall continue to draw power from its input bulk capacitance until VBUS is discharged to vSafe5V or lower by no longer than tSafe5V from the Detach event. This safe Sink requirement Shall apply to all Sinks operating with a Negotiated VBUS level greater than vSafe5V and Shall apply during all low power and high-power operating modes of the Sink. If the Detach is detected during a Sink low power state, such as USB Suspend, the Sink can then draw as much power as needed from its bulk capacitance since a Source is no longer Attached. In order to achieve a successful Detach detect based on VBUS voltage level droop, the Sink power consumption Shall be high enough so that VBUS will decay below vSrcValid(min) well within tSafe5V after the Source bulk capacitance is removed due to the Detach. Once adequate VBUS droop has been achieved, a discharge circuit can be enabled to meet the safe Sink requirement. To illustrate the point, the following set of Sink conditions will not meet the safe Sink requirement without additional discharge circuitry:  Negotiated VBUS = 20V.  Maximum allowable supplied VBUS voltage = 21.55V.  Maximum bulk capacitance = 30µF.  Power consumption at Detach = 12.5mW. When the Detach occurs (hence removal of the Source bulk capacitance) the 12.5mW power consumption will draw down the VBUS voltage from the worst-case maximum level of 21.55V to 17V in approximately 205ms. At this point, with VBUS well below vSrcValid (min) an approximate 100mW discharge circuit can be enabled to increase the rate of Sink bulk capacitance discharge and meet the safe Sink requirement. The power level of the discharge circuit is dependent on how much time is left to discharge the remaining voltage on the Sink bulk capacitance. If a Sink has the ability to detect the Detach in a different manner and in much less time than tSafe5V, then this different manner of detection can be used to enable a discharge circuit, allowing even lower power dissipation during low power modes such as USB Suspend. In most applications, the safe Sink requirement will limit the maximum Sink bulk capacitance well below the cSnkBulkPd limit. A Detach occurring during Sink high power operating modes must quickly discharge the Sink bulk capacitance to vSafe5V or lower as long as the Sink continues to draw adequate power until VBUS has decayed to vSafe5V or lower. 7.2.9.2 Input Over Voltage Protection Sinks Shall implement input Over-Voltage Protection (OVP) to prevent damage from input voltage that exceeds the voltage handling capability of the Sink. The definition of voltage handling capability is left to the discretion of the Sink implementation. The over voltage response of Sinks Shall Not interfere with normal PD operation and Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid as determined by the Negotiated VBUS value. SPR Sinks Should tolerate input voltages as high as vSprMax and Shall meet applicable safety requirements if vSprMax is exceeded. Likewise, EPR Sinks Should tolerate input voltages as high as vEprMax and Shall meet applicable safety requirements if vEprMax is exceeded. Sinks Should attempt to send Hard Reset Signaling when OVP engages followed by an Alert Message indicating an OVP event once an Explicit Contract has been established. The OVP response May engage at either the Port or system level. Systems or ports that have engaged OVP Shall resume USB Default Operation when the Source has re- established vSafe5V on VBUS. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an OVP event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if OVP continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over voltage. Page 338 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.9.3 Over Temperature Protection Sinks Shall implement over temperature protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Sink. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Sink implementation. Sinks Shall attempt to send Hard Reset Signaling when over temperature protection engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The over temperature protection response May engage at either the Port or system level. Systems or ports that have engaged over temperature protection Should attempt to resume USB Default Operation after sufficient cooling is achieved and May latch off to protect the Port or system. The definition of sufficient cooling is left to the discretion of the Sink implementation. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an over temperature event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. 7.2.9.4 Over Current Protection Sinks that operate with a Programmable Power Supply Shall implement their own internal current protection mechanism to protect against internal VBUS current faults as well as erratic Source current regulation. The Sink Shall never draw higher current than the Maximum Current value in the PPS APDO. 7.2.10 Fast Role Swap As described in Section 7.1.13, "Fast Role Swap" a Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port that supports DRP. This configuration is shown in Figure 7.16, "VBUS Power during Fast Role Swap". The Host DRP, upon establishing an Explicit Contract, Shall query the Initial Source's Sink Capabilities to determine whether the Initial Source supports Fast Role Swap, and what level of current it requires. If the Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap required USB Type-C Current bits set, and the Host DRP is able to source the requested current at 5V, the Host DRP May arm itself for Fast Role Swap. If the Host DRP has not queried the Sink Capabilities from the Initial Source, or if the Sink_Capabilities Message reports no Fast Role Swap support or a current that is beyond what the Host DRP is able or willing to source in the event of a Fast Role Swap, the Host DRP Shall Not arm itself for Fast Role Swap and Shall Ignore any Fast Role Swap Requests that are detected. When the Host DRP that supports Fast Role Swap detects the FFast Role Swap Request, the Host DRP Shall stop sinking current and Shall be ready and able to source vSafe5V if the residual VBUS voltage level at the Host DRP connector is greater than vSafe5V. When the residual VBUS voltage level at the Host DRP connector discharges below vSafe5V(min) the Host DRP as the New Source Shall supply vSafe5V to the Hub DRP within tSrcFRSwap. The Host DRP Shall Not enable VBUS discharge circuitry when changing Power Roles from Initial Sink to New Source. The New Source Shall supply vSafe5V at USB Type-C Current (see [USB Type-C 2.4]) at the value Advertised in the Fast Role Swap required USB Type-C Current field (see Section 6.4.1.3.1.6, "Fast Role Swap USB Type-C Current"). All Source requirements Shall apply to the New Source after the Fast Role Swap is complete The Fast Role Swap response of the Hub DRP is described in Section 7.1.13, "Fast Role Swap" since the Hub DRP is operating as the Initial Source prior to the Fast Role Swap. After the Host DRP is providing VBUS power to the Hub DRP, a PS_RDY Message Shall be sent to the Hub DRP as defined by the Fast Role Swap Request and the AMS detailed in Section 7.3.4, "Transitions Caused by Fast Role Swap". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 339 7.3 Transitions The following sections illustrate the power supply's response to various types of Negotiations. The Negotiations are triggered by certain Messages or Signaling. It provides examples of the transitions and is organized around each of the Messages and Signals that result in a response from the power supply. The response to a Message or Signal can result in different transitions depending upon the power supply's starting conditions and the requested change.  Transitions caused by a Request Message:  Generic transition between (A)PDO s:  Increase the current.  Increase the voltage.  Increase the voltage and the current.  Increase the voltage and decrease the current.  Decrease the voltage and increase the current.  Decrease the voltage and the current.  No change in Current or voltage.  Transitions within the same PDO (Fixed Supply, Battery Supply, Variable Supply):  Increase the current.  Decrease the current.  No change in current.  Transitions within the same PPS APDO:  Increasing the Programmable Power Supply (PPS) voltage.  Decreasing the Programmable Power Supply (PPS) voltage.  Increasing the Programmable Power Supply (PPS) Current.  Decreasing the Programmable Power Supply (PPS) Current.  Same Request Programmable Power Supply (PPS).  Transitions within the same AVS APDO:  Increasing the Adjustable Voltage Supply (AVS) voltage  Decreasing the Adjustable Voltage Supply (AVS) voltage  Same Request Adjustable Voltage Supply (AVS)  Transitions caused by the PR_Swap Message:  Source requests a Power Role Swap  Sink requests a Power Role Swap  Transitions caused by Hard Reset Signaling:  Source issues Hard Reset Signaling.  Sink issues Hard Reset Signaling.  Transitions caused by the Fast Role Swap Request:  Source asserts Rd at its preferred [USB Type-C 2.4] current. Page 340 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1 Transitions caused by a Request Message This section describes transitions that are caused by a Request Message. 7.3.1.1 Changing the Source between Different (A)PDOs In these transition descriptions the term (A)PDO is used to describe any Power Data Object, regardless of whether it is a PDO or an APDO in the Capabilities Message. This section describes transitions in response to a Request Message:  From one (A)PDO to another (A)PDO  From an Implicit Contract to an Explicit Contract  From [USB Type-C 2.4]operation to the First Explicit Contract These transitions usually result in a voltage change but is not required. The interaction of the Device Policy Manager, the Port Policy Engine and the Power Supply that Shall be followed when increasing the current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current" and Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The Source voltage as the transition starts Shall be any voltage within the Valid VBUS range of the previous Source PDO or APDO. The Source voltage after the transition is complete Shall be any voltage within the Valid VBUS range of the New Source PDO or APDO. The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current" and Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In this figure, the Sink has previously sent a Request Message to the Source. The voltage is considered to increase if the change from VOLD to VNEW is greater than vSmallStep. The determination Shall be based on the nominal (A)PDO voltage before and after, unless either (A)PDO is Battery Supply or Variable Supply when the worst case of the following is assumed in making this determination.  Minimum voltage to voltage.  Minimum voltage to Maximum voltage.  Voltage to Maximum voltage. The following sections begin with a description of the generic process followed by more specific examples of the most common transitions. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 341 7.3.1.1.1 Examples of changes from one (A)PDO to another (A)PDO The seven examples of (A)PDO change transitions below illustrate the most common transitions. 7.3.1.1.1.1 Increasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage is shown in Figure 7.22, "Transition Diagram for Increasing the Voltage". The sequence that Shall be followed is described in Table 7.1, "Sequence Description for Increasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.22, "Transition Diagram for Increasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 342 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.22 Transition Diagram for Increasing the Voltage t3 t1 t2 Source VOLD Source VNEW Source × V 4 3 7 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply 8 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,2/' Sink ” IOLD ” IOLD ” IOLD Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) VNEW I1 ... § Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 343 Table 7.1 Sequence Description for Increasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 344 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.2 Increasing the Voltage and Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current". The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.23, "Transition Diagram for Increasing the Voltage and Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 345 Figure 7.23 Transition Diagram for Increasing the Voltage and Current t3 Source VOLD Source VNEW Source × V × I 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ”INEW Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD VNEW 3 7 I1 § ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) t2 t1 Page 346 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.2 Sequence Diagram for Increasing the Voltage and Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out, the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 347 7.3.1.1.1.3 Increasing the Voltage and Decreasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and decreasing the current is shown in Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current". The sequence that Shall be followed is described in Table 7.3, "Sequence Description for Increasing the Voltage and Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current", the Sink has previously sent a Request Message to the Source. Page 348 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.24 Transition Diagram for Increasing the Voltage and Decreasing the Current t3 t1 Source VOLD Source VNEW Source × V ØI 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW I1 Sink to Sink Standby Sink Standby to Sink Sink iSnkStdBy VNEW VOLD 3 7 ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) § t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 349 Table 7.3 Sequence Description for Increasing the Voltage and Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 350 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.4 Decreasing the Voltage and Increasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and increasing the current is shown in Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The sequence that Shall be followed is described in Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 351 Figure 7.25 Transition Diagram for Decreasing the Voltage and Increasing the Current t2 Source VOLD Source VNEW Source Ø V × I 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW VNEW VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink × I ... 6 7 t1 Page 352 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.4 Sequence Description for Decreasing the Voltage and Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the PS_RDY Message from the Source and tells the Device Policy Manager it is okay to operate at the new power level. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 353 7.3.1.1.1.5 Decreasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage is shown in Figure 7.26, "Transition Diagram for Decreasing the Voltage". The sequence that Shall be followed is described in Table 7.5, "Sequence Description for Decreasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.26, "Transition Diagram for Decreasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 354 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.26 Transition Diagram for Decreasing the Voltage t Source VOLD Source Ø V 3 Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”IOLD VOLD ” IOLD ” IOLD VNEW Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 355 Table 7.5 Sequence Description for Decreasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 356 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.6 Decreasing the Voltage and the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and current is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.6, "Sequence Description for Decreasing the Voltage and the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.27, "Transition Diagram for Decreasing the Voltage and the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 357 Figure 7.27 Transition Diagram for Decreasing the Voltage and the Current t1 t2 Source Ø V Ø I 4 Source VOLD Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”INEW Sink ”IOLD ” IOLD ” INEW Sink Ø I VNEW VOLD 3 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Page 358 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.6 Sequence Description for Decreasing the Voltage and the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 359 7.3.1.1.1.7 No change in Current or Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while the Sink requests the same voltage and Current as it is currently operating at is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.7, "Sequence Description for no change in Current or Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.28, "Transition Diagram for no change in Current or Voltage", the Sink has previously sent a Request Message to the Source. Page 360 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.28 Transition Diagram for no change in Current or Voltage Table 7.7 Sequence Description for no change in Current or Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine waits tSrcTransition then sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine evaluates the PS_RDY Message. Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink ”IOLD VBUS doesn’t change Source VOLD Current doesn’t change Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tSrcTransition Good CRC Good CRC tSrcTransReq Vold Source VOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 361 7.3.1.2 Transitions within the same Fixed, Battery or Variable PDO or between Different (A)PDOs 7.3.1.2.1 Increasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current without changing the voltage is shown in Figure 7.29, "Transition Diagram for Increasing the Current". The sequence that Shall be followed is described in Table 7.8, "Sequence Description for Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.29, "Transition Diagram for Increasing the Current", the Sink has previously sent a Request Message to the Source. Page 362 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.29 Transition Diagram for Increasing the Current Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Sink ”INEW Source Port Voltage Sink Port Current Sink ”IOLD ” IOLD ” INEW Sink × I VBUS doesn’t change Source × I 3 6 ... 7 § Source VOLD Source VOLD Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Port to Port Messaging Good CRC tSrcTransReq Good CRC Sink Port Policy Engine t1 t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 363 Table 7.8 Sequence Description for Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t2) depends on the magnitude of the load change. Page 364 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.2.2 Decreasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current without changing the voltage is shown in Figure 7.30, "Transition Diagram for Decreasing the Current". The sequence that Shall be followed is described in Table 7.9, "Sequence Description for Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.30, "Transition Diagram for Decreasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 365 Figure 7.30 Transition Diagram for Decreasing the Current Source VOLD Source VOLD Sink ”IOLD Sink ”INEW VBUS does not change Source Ø I 4 3 ” IOLD ” INEW Sink Ø I Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC t1 t2 Page 366 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.9 Sequence Description for Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. Policy Engine tells the Device Policy Manager to instruct the power supply to reduce power consumption. 3 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 367 7.3.1.3 Changing Voltage or Current within the same PPS APDO 7.3.1.3.1 Increasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.10, "Sequence Description for Increasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Page 368 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.31 Transition Diagram for Increasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Current may change (not to exceed negotiated current) Source CL Current Sink VBUS Current Sink Port Current VOLD Source Port Voltage VNEW Source VBUS Voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 369 Table 7.10 Sequence Description for Increasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to increase its output voltage. The Programmable Power Supply new voltage set- point Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new set-point and whether VBUS is at the corresponding new level, or if the supply is operating in CL mode. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 370 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.2 Decreasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.11, "Sequence Description for Decreasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 371 Figure 7.32 Transition Diagram for Decreasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Source CL Current Current may change (not to exceed negotiated current) Sink VBUS Current Sink Port Current Page 372 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.11 Sequence Description for Decreasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to decrease its output voltage. The Programmable Power Supply new voltage set- point (corresponding to vPpsNew) Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 373 7.3.1.3.3 Increasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current limit in the same APDO, not exceeding the maximum for that APDO and without changing the requested voltage is shown in Figure 7.33, "Transition Diagram for increasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.12, "Sequence Description for increasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.33, "Transition Diagram for increasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. The Sink May draw current equal to the increasing Current Limit of the Source before it has received the PS_RDY Message for the new Request. Page 374 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.33 Transition Diagram for increasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ĺ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 375 Table 7.12 Sequence Description for increasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Power Supply increases its Current Limit set- point to the new requested value. The Sink draws current according to the increased Current Limit of the Source. 4 The Policy Engine waits tPpsSrcTransSmall then sends the PS_RDY Message to the Sink starting within tPpsCLProgramSettle of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. 6 Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message and tells the Device Policy Manager it can increase the current up to the requested value without the Source going into CL mode. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink increases its current. Page 376 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.4 Decreasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current limit in the same APDO, not exceeding the minimum for that APDO and without changing the requested voltage is shown in Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.13, "Sequence Description for decreasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 377 Figure 7.34 Transition Diagram for decreasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ļ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Set-point V does not change, only resulting V Page 378 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.13 Sequence Description for decreasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and instructs the Sink to reduce its current to below the new Negotiated current level and starts the PSTransitionTimer. 3 The Power Supply decreases its Current Limit set- point to the new Negotiated value. The Sink reduces its current to less than the new Negotiated current to prevent the Source from going into Current Limit. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Policy Engine receives the PS_RDY Message. 6 Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink is allowed to draw INEW but must be aware the voltage on VBUS can drop doing so. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 379 7.3.1.3.5 Same Request Programmable Power Supply (PPS) The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current is shown in Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode". The sequence that Shall be followed is described in Table 7.14, "Sequence Description for no change in Current or Voltage in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode", the Sink has previ- ously sent a Request Message to the Source. Page 380 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.35 Transition Diagram for no change in Current or Voltage in PPS mode Table 7.14 Sequence Description for no change in Current or Voltage in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and starts the PSTransitionTimer. 3 The Policy Engine then sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Source IOLD Sink ” IOLD Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD Sink Port Current Source CL Current CL doesn’t change Current doesn’t change VBUS doesn’t change Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 381 7.3.1.4 Changing Voltage or Current within the same AVS APDO 7.3.1.4.1 Increasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.15, "Sequence Description for Increasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed inTable 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage", the Sink has pre- viously sent a Request Message to the Source. Page 382 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.36 Transition Diagram for Increasing the Adjustable Power Supply Voltage AVS Transition Interval Source VOLD Source VNEW Sink draws current continuously for voltage changes less than or equal to vAvsSmallStep. For larger voltage changes, the Sink reduces to iSnkStdby. IOLD VOLD Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Depends on magnitude of AVS voltage change Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 383 Table 7.15 Sequence Description for Increasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. If the voltage increase is larger than vAvsSmallStep, the Sink Shall reduce its current draw to iSnkStdby within tSnkStdby. The reduction to iSnkStdby is not required if the voltage increase is less than or equal to vAvsSmallStep. 3 After sending the Accept Message, the AVS starts to increase its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point. The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 384 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.4.2 Decreasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage". The sequence that Shall be followed is described in Table 7.16, "Sequence Description for Decreasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 385 Figure 7.37 Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage AVS Transition Interval Source VOLD Source VNEW ”IOLD VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Sink ”IOLD Page 386 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.16 Sequence Description for Decreasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the AVS starts to decrease its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vAvsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 387 7.3.1.4.3 Same Request Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current as shown in Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode". The sequence that Shall be followed is described in Table 7.17, "Sequence Description for no change in Current or Voltage in AVS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode", the Sink has previ- ously sent a Request Message to the Source. Figure 7.38 Transition Diagram for no change in Current or Voltage in AVS mode Table 7.17 Sequence Description for no change in Current or Voltage in AVS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 4 Protocol Layer receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Current doesn’t change VBUS doesn’t change Source Port Policy Engine Sink Port Policy Engine Source Port Voltage Sink Port Current Port to Port Messaging Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Page 388 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2 Transitions Caused by Power Role Swap 7.3.2.1 Sink Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink requested Power Role Swap is shown in Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.18, "Sequence Description for a Sink Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap", the Sink has previously sent a PR_Swap Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 389 Figure 7.39 Transition Diagram for a Sink Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 3 4 7 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSSourceOffTimer tSrcTransition Good CRC tSrcTransOff Good CRC PSSourceOnTimer Send PS_RDY Evaluate PS_RDY Good CRC 8 9 tSrcTransOn Page 390 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.18 Sequence Description for a Sink Requested Power Role Swap Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port 1 Policy Engine sends the Accept Message to the Initial Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Initial Source. Policy Engine then starts the PSSourceOffTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition min. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 5 The power supply is ready, and the Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. 6 Protocol Layer receives the GoodCRC Message from the device that will become the New Source. Policy Engine starts the PSSourceOnTimer. Upon sending the PS_RDY Message and receiving the GoodCRC Message the Initial Source is ready to be the New Sink. The Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine the stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 8 Policy Engine receives the PS_RDY Message from the Source. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 391 9 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 10 The power supply as the New Sink transitions from Swap Standby and begins to drawing the current allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.18 Sequence Description for a Sink Requested Power Role Swap (Continued) Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port Page 392 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2.2 Source Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source requested Power Role Swap is shown in Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.19, "Sequence Description for a Source Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap", the Source has previously sent a PR_Swap Message to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 393 Figure 7.40 Transition Diagram for a Source Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 2a 4 6 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSSourceOffTimer (running) tSrcTransition Good CRC Good CRC PSSourceOnTimer (running) Send PS_RDY Evaluate PS_RDY Good CRC 7 9 Page 394 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.19 Sequence Description for a Source Requested Power Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port 1 Policy Engine receives the Accept Message. Policy Engine sends the Accept Message to the Initial Source. 2 Protocol Layer sends the GoodCRC Message to the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer receives the GoodCRC Message from the Initial Source. Policy Engine starts the PSSourceOffTimer. 2a The Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby. The power supply Shall complete the transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). 3 tSrcTransition after the GoodCRC Message was sent the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY. 5 Protocol Layer receives the GoodCRC Message from the soon to be New Source. Policy Engine starts the PSSourceOnTimer. At this point the Initial Source is ready to be the New Sink. Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine then stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before the PSSourceOffTimer times out the Sink starts sending Hard Reset Signaling. 6 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 7 Policy Engine receives the PS_RDY Message. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 395 8 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 9 The power supply as the New Sink transitions from Swap Standby to drawing the power allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The New Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.19 Sequence Description for a Source Requested Power Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 396 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3 Transitions Caused by Hard Reset 7.3.3.1 Source Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source Initiated Hard Reset is shown in Figure 7.41, "Transition Diagram for a Source Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.20, "Sequence Description for a Source Initiated Hard Reset". The timing parameters that Shall be applied are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 397 Figure 7.41 Transition Diagram for a Source Initiated Hard Reset Table 7.20 Sequence Description for a Source Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Sink. Sink receives Hard Reset Signaling. 2 Policy Engine is informed of the Hard Reset. Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine waits tPSHardReset after sending Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 5 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 Source VOLD Send Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 vSafe5V Default current draw § § Source vSafe5V 4 Source vSafe0V Sink ” IOLD Ready to recover and power up Source Recover tSrcRecover 5 Process Hard Reset tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current 2 t2 t1 Page 398 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3.2 Sink Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink Initiated Hard Reset is shown in Figure 7.42, "Transition Diagram for a Sink Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.21, "Sequence Description for a Sink Initiated Hard Reset". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 399 Figure 7.42 Transition Diagram for a Sink Initiated Hard Reset Table 7.21 Sequence Description for a Sink Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Source. 2 Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager. The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine is informed of the Hard Reset. 5 Policy Engine waits tPSHardReset after receiving Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 6 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 t2 Send Hard Reset Evaluate Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 4 vSafe5V Defalt current draw § § Source vSafe5V 5 Source vSafe0V Sink ” IOLD Source VOLD Ready to recover and power up Source Recover tSrcRecover 6 tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Process Hard Reset 2 t1 Page 400 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.4 Transitions Caused by Fast Role Swap 7.3.4.1 Fast Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Fast Role Swap is shown in Figure 7.43, "Transition Diagram for Fast Role Swap". The parallel sequences that Shall be followed are described in Table 7.22, "Sequence Description for Fast Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Negotiations between the New Source and the New Sink May occur after the New Source sends the final PS_RDY Message. Note: In Figure 7.43, "Transition Diagram for Fast Role Swap". and Table 7.22, "Sequence Description for Fast Role Swap" numbers are used to indicate Message related steps and letters are used to indicate other events. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 401 Figure 7.43 Transition Diagram for Fast Role Swap Rp Changed to Rd Signal Fast Swap Detect Fast Swap Old Sink New Sink Old Source A B 2 C Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Path Sink Port Device Policy Mgr Sink Port Power Path Source Port Voltage Sink Port Current Port to Port Signaling & Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Stops Send FR_Swap 1 Send Accept Evaluate FR_Swap New Source = vSafe5V Evaluate Accept 3 4 Send PS_RDY Evaluate PS_RDY D1 Sink 5 6 Source VBUS< vSafe5V Send PS_RDY 7 VBUS< vSafe5V Source VBUS Source vSafe5V D2 E Ready & Able to Source vSafe5V Evaluate PS_RDY 8 tFRSwapInit Rd Changed to Rp F G 0 A < tSrcFRSwap discharging Sink 0 V Any voltage > vSafe5V No current may be drawn while VBUS is below vSafe5V Page 402 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.22 Sequence Description for Fast Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Fast Role Swap Request and Power Transition A The Source connected to the Hub UFP (see Figure 7.16, "VBUS Power during Fast Role Swap") stops sourcing VBUS. B Policy Engine sends the Fast Role Swap Request to the Initial Sink on the CC wire. When VBUS < vSafe5V (min), it tells the Device Policy Manager not to draw more than iSnkStdby until the tSnkFRSwap timer has elapsed. C Policy Engine detects the Fast Role Swap Request on the CC wire from the Initial Source and Shall send the FR_Swap Message back to the Initial Source (that is no longer powering VBUS) within time tFRSwapInit. D1 The Policy Engine monitors for VBUS ≤ vSafe5V so that a PS_RDY Message can be sent to the New Source at Step 5 of the messaging sequence. D2 The Policy Engine monitors for VBUS ≤ vSafe5V so the Initial Sink can assume the Power Role of New Source and begin to source VBUS. E When VBUS = vSafe5V the New Source May provide power to VBUS. When VBUS < vSafe5V the New Source Shall provide power to VBUS within tSrcFRSwap. Once the New Source is providing power, the PS_RDY Message can be sent to the New Sink at Step 7 of the messaging sequence. F The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]) before the New Sink sends the PS_RDY Message at Step 5 to the New Source. G The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]) before the New Source sends the PS_RDY Message at Step 7 to the New Sink. Fast Role Swap Message Sequence 1 Policy Engine receives the FR_Swap Message from the Initial Sink that is transitioning to be the New Source. Policy Engine sends the FR_Swap Message to the Initial Source (that is no longer powering VBUS) after detecting the Fast Role Swap Request at Step C. 2 Protocol Layer sends the GoodCRC Message to the Initial Sink. Policy Engine then evaluates the FR_Swap Message. Protocol Layer receives the GoodCRC Message from the Initial Source. 3 Policy Engine sends an Accept Message to the Initial Sink that is transitioning to be the New Source. Policy Engine receives the Accept Message from the Initial Source that is transitioning to be the New Sink. 4 Protocol Layer receives the GoodCRC Message from the Initial Sink that is transitioning to be the New Source. Protocol Layer sends the GoodCRC Message to the Initial Source that is transitioning to be the New Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 403 5 Policy Engine sends a PS_RDY Message to the Initial Sink that is transitioning to be the New Source. The Policy Engine Shall start the PS_RDY Message at least tFRSwap5V after it has sent the Accept Message, and when Step D1 has also been completed. Policy Engine receives the PS_RDY Message from the New Sink. 6 Protocol Layer receives the GoodCRC Message from the New Source. Protocol Layer sends the GoodCRC Message from the Initial Sink that has completed the transition to New Source. Policy Engine then evaluates the PS_RDY Message. 7 Policy Engine receives the PS_RDY Message from the New Source. Policy Engine sends a PS_RDY Message to the New Sink. The Policy Engine Shall wait for Step E before sending the PS_RDY Message, and Shall send the PS_RDY Message within tFRSwapComplete of receiving the PS_RDY Message from the Initial Source Port. Table 7.22 Sequence Description for Fast Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 404 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.4 Electrical Parameters 7.4.1 Source Electrical Parameters The Source Electrical Parameters that Shall be followed are specified in Table 7.23, "Source Electrical Parameters". Table 7.23 Source Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSrcBulk Source bulk capacitance when a Port is powered from a dedicated supply.1 10 µF Section 7.1.2 cSrcBulkShared Source bulk capacitance when a Port is powered from a shared supply.1 120 µF Section 7.1.2 DNL (Differential Non- Linearity) Deviation between ideal analog values corresponding to adjacent input digital values -1 0 +1 LSB Section 7.1.4.2.1 iPpsCLMin SPR PPS Minimum Current Limit setting. 1 A Section 7.1.4.2.2 iPpsCLNew Current Limit accuracy Section 7.1.4.2.2 1A ≤ Operating Current ≤ 3A -150 150 mA Operating current > 3A -5 5 % iPpsCLStep SPR PPS Current Limit programming step size (1 LSB). 50 mA Section 7.1.4.2.2 iPpsCLLoadReleaseRate Maximum load decrease slew rate during Current Limit set-point changes. -150 mA/µs Section 7.1.4.2.2 iPpsCLLoadStepRate Maximum load increase slew rate during Current Limit set-point changes. 150 mA/µs Section 7.1.4.2.2 iPpsCLTransient Allowed output current overshoot when a load increase occurs while in CL mode. New load + 100 mA Section 7.1.4.2.2 Allowed output current undershoot when a load decrease occurs while in CL mode. New load – 100 mA 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 405 iPpsCVCLTransient CV to CL transient current bounds assuming the Operating Voltage reduction of Section 7.2.3.1, "Programmable Power Supply Sink Standby". iPpsCLNe w - 100 New load + 500 mA Section 7.1.4.2.2 tAvsTransient The maximum time for the AVS to be between vAvsNew and vAvsValid in response to a load transient. 5 ms Section 7.1.8.4 tAvsSrcTransLarge The time the AVS set- point Shall transition between requested voltages for steps larger than vAvsSmallStep. 0 700 ms Section 7.1.4.3.1 tAvsSrcTransSmall The time the AVS set- point Shall transition between requested voltages for steps smaller than vAvsSmallStep. 0 50 ms Section 7.1.4.3.1 tNewSnk Time allowed for an Initial Source in Swap Standby to transition New Sink operation. 15 ms Section 7.1.10 Figure 7.39 Figure 7.40 tPpsCLCVTransient CL to CV transient voltage settling time. 275 ms Section 7.1.4.2.2 tPpsCLProgramSettle SPR PPS Current Limit programming settling time. 250 ms Section 7.1.4.2.2 tPpsCLSettle CL load transient current settling time. 250 ms Section 7.1.4.2.2 tPpsCVCLTransient CV to CL transient settling time. 250 ms Section 7.1.8.3 tPpsSrcTransLarge The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps larger than vPpsSmallStep. 0 275 ms Section 7.3.1.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 406 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tPpsSrcTransSmall The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps less than or equal to vPpsSmallStep. 0 25 ms Section 7.3.1.3 tPpsTransient The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is greater than or equal to 60mA. 5 ms Section 7.1.8.3 The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8.3 tSrcFRSwap Time from the Initial Sink detecting that VBUS has dropped below vSafe5V until the Initial Sink/new Source is able to supply USB Type-C Current (see [USB Type-C 2.4]) 150 µs Section 7.1.13 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 407 tSrcReady SPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies only to SPR Mode voltage transitions. 285 ms Figure 7.2 Figure 7.3 EPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 720 tSrcRecover SPR Mode Time allotted for the Source to recover. 0.66 1.0 s Section 7.1.5 EPR Mode 1.085 1.425 tSrcSettle SPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vSrcNew. Applies only to SPR Mode voltage transitions. 275 ms Figure 7.2 EPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vAvsNew. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 700 tSrcSwapStdby The maximum time for the Source to transition to Swap Standby. 650 ms Section 7.1.10 Figure 7.17 Figure 7.18 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 408 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tSrcTransient The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is greater or equal to than 60mA. 5 ms Section 7.1.8 The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8 tSrcTransition The time the Source Shall wait before transitioning the power supply to ensure that the Sink has sufficient time to prepare (does not apply to transitions within the same PPS or AVS APDO). 25 35 ms Section 7.3 tSrcTransOff SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the PR_Swap Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 690 ms Section 7.3.2 tSrcTransOn Time from the last bit of the GoodCRC Message acknowledging the PS_RDY Message sent by the new Source, in response to the PR_Swap Message until the PS_RDY Message must be started. 280 ms Section 7.3.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 409 tSrcTransReq SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 325 ms Section 7.3 EPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 760 ms Section 7.3 tSrcTurnOn Transition time from vSafe0V to vSafe5V. 275 ms Figure 7.10 Table 7.20 Table 7.21 vAvsMaxVoltage Maximum Voltage Field in the AVS APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.3.1 vAvsMinVoltage Minimum Voltage Field in the AVS APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.3.1 vAvsNew Adjustable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.4 vAvsSlewNeg AVS maximum slew rate for negative voltage changes. -30 mV/µs Section 7.1.8.4 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 410 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vAvsSlewPos AVS maximum slew rate for positive voltage changes. 30 mV/µs Section 7.1.8.4 vAvsSmallStep AVS step size defined as a small step relative to the previous vAvsNew. -1.0 1.0 V Section 7.1.4.3.1 vAvsStep AVS voltage programming step size. 100 mV Section 7.1.8.4 vAvsValid The range in addition to vAvsNew which the AVS output is considered Valid during and after a transition as well as in response to a transient load condition. -0.5 0.5 V Section 7.1.8.4 vPpsCLCVTransient CL to CV load transient voltage bounds. Operating Voltage * 0.95 – 0.1V Operating Voltage * 1.05 + 0.1V V Section 7.1.4.2.2 vPpsMaxVoltage Maximum Voltage Field in the Programmable Power Supply APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.2.1 vPpsMinVoltage Minimum Voltage Field in the Programmable Power Supply APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.2.1 vPpsNew Programmable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.3 vPpsShutdown The voltage at which the SPR PPS shuts down when operating in CL. APDO Minimum Voltage * 0.85 APDO Minimum Voltage * 0.95 V Section 7.1.4.2.2 vPpsSlewNeg Programmable Power Supply maximum slew rate for negative voltage changes -30 mV/µs Section 7.1.8.3 vPpsSlewPos Programmable Power Supply maximum slew rate for positive voltage changes 30 mV/µs Section 7.1.8.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 411 vPpsSmallStep PPS Step size defined as a small step relative to the previous vPpsNew. -500 500 mV Section 7.1.4.2.2 vPpsStep PPS voltage programming step size (1 LSB). 20 mV Section 7.1.8.3 vPpsValid The range in addition to vPpsNew which the Programmable Power Supply output is considered Valid in response to a load step. -0.1 0.1 V Section 7.1.8.3 vSmallStep VBUS step size increase defined as a small step relative to the previous VBUS when Requesting a different (A)PDO. 500 mV Section 7.1.4.3.1 vSrcNeg Most negative voltage allowed during transition. -0.3 V Figure 7.10 vSrcNew Fixed Supply output measured at the Source receptacle. PDO Voltage *0.95 PDO Voltage PDO Voltage *1.05 V Table 7.2 Variable Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V Battery Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V vSrcPeak The range that a Fixed Supply or EPR AVS in Peak Current operation is allowed when overload conditions occur. PDO Voltage *0.90 PDO Voltage *1.05 V Table 6.10 Table 6.16 Figure 7.14 vSrcSlewNeg Maximum slew rate allowed for negative voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. -30 mV/µs Section 7.1.4.2 Table 7.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 412 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vSrcSlewPos Maximum slew rate allowed for positive voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. 30 mV/µs Section 7.1.4 Figure 7.2 vSrcValid The range in addition to vSrcNew which a newly Negotiated voltage is considered Valid during and after a transition as well as in response to a transient load condition. This range also applies to vSafe5V. -0.5 0.5 V Figure 7.2 Figure 7.3 Section 7.1.8 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 413 7.4.2 Sink Electrical Parameters The Sink Electrical Parameters that Shall be followed are specified in Table 7.24, "Sink Electrical Parameters". Table 7.24 Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSnkBulk Sink bulk capacitance on VBUS at Attach and during FRS after the Initial Source stops sourcing and prior to establishing the First Explicit Contract (see Appendix E, "FRS System Level Example" for an example).1 See [USB 3.2] Section 7.2.2 [USB 3.2] cSnkBulkPd Bulk capacitance on VBUS a Sink is allowed after a successful Negotiation.1 100 µF Section 7.2.2 iLoadReleaseRate Load release di/dt. -150 mA/ µs Section 7.2.6 iLoadStepRate Load step di/dt. 150 mA/ µs Section 7.2.6 iNewFrsSink Maximum current the New Sink can draw during a Fast Role Swap until the New Source applies Rp. Matches the required Fast Role Swap required USB Type-C Current Current field of the Fixed Supply PDO of the Initial Source’s Sink_Capabilities Message. Default USB current or 1.5 or 3.0 A Section 7.1.13 iOvershoot Positive or negative overshoot when a load change occurs less than or equal to iLoadStepRate; relative to the settled value after the load change. -230 230 mA Section 7.2.6 iPpsCLLoadStep Maximum Current set-point change while operating in CL mode. -500 500 mA Section 7.2.3.1 iSafe0mA Maximum current a Sink is allowed to draw when VBUS is driven to vSafe0V. 1.0 mA Figure 7.29 Figure 7.30 iSnkStdby Maximum current during voltage transition. 500 mA Section 7.2.3 iSnkSwapStdby Maximum current a Sink can draw during Swap Standby. Ideally this current is very near to 0 mA largely influenced by Port leakage current. 2.5 mA Section 7.2.7 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Page 414 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 pHubSusp Suspend power consumption for a Hub. 25mW + 25mW per downstream Port for up to 4 ports. 125 mW Section 7.2.3 pSnkSusp Suspend power consumption for a peripheral device. 25 mW Section 7.2.3 tNewSrc Maximum time allowed for an Initial Sink in Swap Standby to transition to New Source operation. 275 ms Section 7.2.7 Table 7.18 Table 7.19 tSnkFRSwap Time during a Fast Role Swap when the New Sink can draw no more than iSnkStdby. 200 µs Section 7.1.13 tSnkHardResetPrepare Time allotted for the Sink power electronics to prepare for a Hard Reset. 15 ms Table 7.12 tSnkNewPower Maximum transition time between power levels. 15 ms Section 7.2.3 tSnkRecover Time for the Sink to resume USB Default Operation. 150 ms Table 7.20 tSnkStdby Time to transition to Sink Standby from Sink. 15 ms Section 7.2.3 tSnkSwapStdby Maximum time for the Sink to transition to Swap Standby. 15 ms Section 7.2.7 vEprMax Highest voltage an EPR Sink is expected to tolerate 55 V Section 7.2.9.2 vSprMax Highest voltage an SPR Sink is expected to tolerate 24 V Section 7.2.9.2 Table 7.24 Sink Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 415 7.4.3 Common Electrical Parameters Electrical Parameters that are common to both the Source and the Sink that Shall be followed are specified in Table 7.25, "Common Source/Sink Electrical Parameters"”. Table 7.25 Common Source/Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference tSafe0V Time to reach vSafe0V max. 650 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tSafe5V Time to reach vSafe5V max. 275 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tVCONNReapplied When the UFP is the VCONN Source: time from the last bit of the GoodCRC acknowledging the PS_RDY Message before reapplying VCONN. When the DFP is the VCONN Source: time from when VCONN drops below vRaReconnect. 10 20 ms Figure 7.19 Figure 7.20 tVCONNValid Time from tVCONNReapplied until VCONN is within vVconnValid (see [USB Type-C 2.4]).1 0 5 ms Figure 7.19 Figure 7.20 tVCONNZero Time from the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message until VCONN is below vRaReconnect (see [USB Type-C 2.4]). 125 ms Figure 7.19 Figure 7.20 vSafe0V Safe operating voltage at “zero volts”. 0 0.8 V Section 7.1.5 vSafe5V Safe operating voltage at 5V. See [USB 2.0] and [USB 3.2] for allowable VBUS voltage range. 4.75 5.5 V Section 7.1.5 1) tVCONNStable (See [USB Type-C 2.4]) still applies. Page 416 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy 8.1 Overview This section describes the Device Policy and Policy Engine that implements it. For an overview of the architecture and how the Device Policy Manager fits into this architecture, please see Section 2.6, "Architectural Overview". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 417 8.2 Device Policy Manager The Device Policy Manager is responsible for managing the power used by one or more USB Power Delivery ports. In order to have sufficient knowledge to complete this task it needs relevant information about the device it resides in. Firstly, it has a priori knowledge of the device including the Capabilities of the power supply and the receptacles on each Port since these will for example have specific current ratings. It also has to know information from the USB-C® Port Control module regarding cable insertion, type and rating of cable etc. It also has to have information from the power supply about changes in its Capabilities as well as being able to request power supply changes. With all of this information the Device Policy Manager is able to provide up to date information regarding the Capabilities available to a specific Port and to manage the power resources within the device. When working out the Capabilities for a given Source Port the Device Policy Manager will take into account firstly the current rating of the Port's receptacle and whether the inserted cable is PD or non-PD rated and if so, what is the capability of the plug. This will set an upper bound for the Capabilities which might be offered. After this the Device Policy Manager will consider the available power supply resources since this will bound which voltages and currents might be offered. Finally, the Device Policy Manager will consider what power is currently allocated to other ports, which power is in the Power Reserve and any other amendments to Policy from the System Policy Manager. The Device Policy Manager will offer a set of Capabilities within the bounds detailed above. When selecting a capability for a given Sink Port the Device Policy Manager will look at the Capabilities offered by the Source. This will set an upper bound for the Capabilities which might be requested. The Device Policy Manager will also consider which Capabilities are required by the Sink in order to operate. If an appropriate match for voltage and Current can be found within the limits of the receptacle and cable, then this will be requested from the Source. If an appropriate match cannot be found then a request for an offered voltage and current will be made, along with an indication of a Capabilities Mismatch. USB PD defines two types of power sources:  Predefined voltage sources (Fixed Supply, Variable Supply and Battery Supply)  Programmable voltage sources:  Programmable Power Supply (PPS)  Adjustable Voltage Supply (AVS) The first are generally used for classic charging wherein the Charger electronics reside inside the Sink. The Device Policy Manager in the Sink requests a fixed voltage from the list of PDOs offered by the Source and which is converted internally to charge the Sink's Battery and/or power its function. The second moves the Charger electronics that manage the voltage control outside the Sink and back into the Source itself. When in SPR PPS Mode, the Device Policy Manager in the Sink requests a specific voltage with a 20mV accuracy and sets a current limit. Unlike traditional USB where Sinks are responsible for limiting the current, they consume, the SPR PPS Source limits the current to what the Sink has requested. When operating in, the Device Policy Manager in the Sink requests a specific voltage with a 100mV accuracy and requests a maximum current it is allowed to draw. Note: The AVS Sources unlike SPR PPS Sources do not support current limit mode. A Sink operating in is respon- sible not to draw more current than it requests. The process to request power is the same for both types of power Sources although the actual format and contents of the request are slightly different. The primary operational differences are:  A Sink that is using SPR PPS is required to periodically sent requests to let the Source know it is still alive and communicating. When this communication fails a Hard Reset results.  A Sink operating in SPR Mode has no special timing requirements.  A Sink operating in EPR Mode is required to periodically communicate with the Source to let it know it is still operational. If the communication fails, a Hard Reset results. For Dual-Role Power Ports the Device Policy Manager manages the functionality of both a Source and a Sink. In addition, it is able to manage the Power Role Swap process between the two. In terms of power management this Page 418 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 could mean that a Port which is initially consuming power as a Sink is able to become a power resource as a Source. Conversely, Attached Sources might request that power be provided to them. The functionality within the Device Policy Manager (and to a certain extent the Policy Engine) is scalable depending on the complexity of the device, including the number of different power supply Capabilities and the number of different features supported for example System Policy Manager interface or Capabilities Mismatch, and the number of ports being managed. Within these parameters it is possible to implement devices from very simple power supplies to more complex power supplies or devices such as USB Hubs or Hard Drives. Within multi-Port devices it is also permitted to have a combination of USB Power Delivery and non-USB Power Delivery ports which Should all be managed by the Device Policy Manager. As noted in Section 2.6, "Architectural Overview" the logical architecture used in the PD specification will vary depending on the implementation. This means that different implementations of the Device Policy Manager might be relatively small or large depending on the complexity of the device, as indicated above. It is also possible to allocate different responsibilities between the Policy Engine and the Device Policy Manager, which will lead to different types of architectures and interfaces. The Device Policy Manager is responsible for the following:  Maintaining the Local Policy for the device.  For a Source, monitoring the present Capabilities and triggering notifications of the change.  For a Sink, evaluating and responding to Capabilities related requests from the Policy Engine for a given Port.  Control of the Source/Sink in the device.  Control of the USB-C® Port Control module for each Port.  Interface to the Policy Engine for a given Port. The Device Policy Manager is responsible for the following Optional features when implemented:  Communications with the System Policy over USB.  For Sources with multiple ports monitoring and balancing power requirements across these ports.  Monitoring of batteries and AC power supplies.  Managing Modes in its Port Partner and Cable Plug(s). 8.2.1 Capabilities The Device Policy Manager in a Provider Shall know the power supplies available in the device and their Capabilities. In addition, it Shall be aware of any other PD sources of power such as batteries and AC inputs. The available power sources and existing demands on the device Shall be taken into account when presenting Capabilities to a Sink. The Device Policy Manager in a Consumer Shall know the requirements of the Sink and use this to evaluate the Capabilities offered by a Source. It Shall be aware of its own power sources e.g., Batteries or AC supplies where these have a bearing on its operation as a Sink. The Device Policy Manager in a Dual-Role Power Device Shall combine the above Capabilities and Shall also be able to present the dual-role nature of the device to an Attached PD Capable device. 8.2.2 System Policy A given PD Capable device might have no USB capability, or PD might have been added to a USB device in such a way that PD is not integrated with USB. In these two cases there Shall be no requirement for the Device Policy Manager to interact with the USB interface of the device. The following requirements Shall only apply to PD devices that expose PD functionality over USB. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 419 The Device Policy Manager Shall communicate over USB with the System Policy Manager according to the requirements detailed in [UCSI]. Whenever requested the Device Policy Manager Shall implement a Local Policy according to that requested by the System Policy Manager. For example, the System Policy Manager might request that a Battery powered Device temporarily stops charging so that there is sufficient power for an HDD to spin up. Note: Due to timing constraints, a PD Capable device Shall be able to respond autonomously to all time-critical PD related requests. 8.2.3 Control of Source/Sink The Device Policy Manager for a Provider Shall manage the power supply for each PD Source Port and Shall know at any given time what the Negotiated power is. It Shall request transitions of the supply and inform the Policy Engine whenever a transition completes. The Device Policy Manager for a Consumer Shall manage the Sink for each PD Sink Port and Shall know at any given time what the Negotiated power is. The Device Policy Manager for a Dual-Role Power Device Shall manage the transition between Source/Sink Power Roles for each PD Dual-Role Power Port and Shall know at any given time what Power Role the Port is in. 8.2.4 Cable Detection 8.2.4.1 Device Policy Manager in a Provider The Device Policy Manager in the Provider Shall control the USB-C® Port Control module and Shall be able to use the USB-C® Port Control module to determine the Attachment status. Note: It might be necessary for the Device Policy Manager to also initiate additional discovery using the Discov- er Identity Command in order to determine the full Capabilities of the cabling (see Section 6.4.4.3.1, "Dis- cover Identity"). 8.2.4.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer controls the USB-C® Port Control module and Shall be able to use the USB- C® Port Control module to determine the Attachment status. 8.2.4.3 Device Policy Manager in a Consumer/Provider The Device Policy Manager in a Consumer/Provider inherits characteristics of Consumers and Providers and Shall control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Attachment of a USB Power Delivery Provider/Consumer which supports Dead Battery back-powering.  Presence of VBUS. 8.2.4.4 Device Policy Manager in a Provider/Consumer The Device Policy Manager in a Provider/Consumer inherits characteristics of Consumers and Providers and May control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Presence of VBUS. Page 420 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.2.5 Managing Power Requirements It is the responsibility of the Device Policy Manager in a Provider to be aware of the power requirements of all devices connected to its Source Ports. This includes being aware of any reserve power that might be required by devices in the future and ensuring that power is shared optimally amongst Attached PD Capable devices. This is a key function of the Device Policy Manager; whose implementation is critical to ensuring that all PD Capable devices get the power they require in a timely fashion in order to facilitate smooth operation. This is balanced by the fact that the Device Policy Manager is responsible for managing the sources of power that are, by definition, finite. The Consumer's Device Policy Manager Shall ensure that it takes no more power than is required to perform its functions and when its requirements change, it Should make a new Request. The Provider, after satisfying the Request, Should reclaim any unused power to ensure that it can meet total power requirements of Attached Sinks on at least one Port. Note: It is expected that a future design guide will provide additional guidance. 8.2.5.1 Managing the Power Reserve There might be some products where a Device has certain functionality at one power level and a greater functionality at another, for example a Printer/Scanner that operates only as a printer with one power level and as a scanner if it can get more power. While the visibility of the linkage between power and functionality might only be apparent to the USB Host; the Device Policy Manager Should provide mechanisms to manage the power requirements of such Devices. It is the Device Policy Manager's responsibility to allocate power and maintain a power reserve so as not to over- subscribe its available power resource. A Device with multiple ports such as a Hub Shall always attempt to meet the incremental demands of the Port requiring the highest incremental power from its power reserve. 8.2.5.2 Power Capability Mismatch A Capabilities Mismatch occurs when a Consumer cannot obtain required power from a Provider (or the Source is not PD Capable) and the Consumer requires such Capabilities to operate. Different actions are taken by the Device Policy Manager and the System Policy Manager in this case. 8.2.5.2.1 Local device handling of mismatch The Consumer's Device Policy Manager Shall cause a notification to be displayed to the end user that a power Capabilities Mismatch has occurred. Examples of such feedback can include:  For a simple Device an LED May be used to indicate the failure. For example, during connection the LED could be solid amber. If the connection is successful, the LED could change to green. If the connection fails, it could be red or alternately blink amber.  A more sophisticated Device with a user interface, e.g., a mobile device or monitor, Should provide no- tification through the user interface on the Device. The Provider's Device Policy Manager May cause a notification to be displayed to the user of the power Capabilities Mismatch. Because the Capabilities Mismatch might not cause operational failure, the Provider's Device Policy Manager Should Not display a notification to the user if the power offered to the Sink meets or exceeds the SPR Sink Minimum PDP/ EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). If a notification is displayed, it Should Not be shown as an error unless the power offered to the Sink is less than the SPR Sink Minimum PDP/EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message. 8.2.5.2.2 Device Policy Manager Communication with System Policy In a USB Power Delivery aware system with an active System Policy Manager (see Section 8.2.2, "System Policy"), the Device Policy Manager Shall notify the System Policy Manager of the mismatch. This information Shall be passed back to the System Policy Manager using the mechanisms described in [UCSI]. The System Policy Manager Should Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 421 ensure that the user is informed of the condition. When another Port in the system could satisfy the Consumer's power requirements the user Should be directed to move the Device to the alternate Port. In order to identify a more suitable Source Port for the Consumer the System Policy Manager Shall communicate with the Device Policy Manager in order to determine the Consumer's requirements. The Device Policy Manager Shall use a Get_Sink_Cap Message (see Section 6.3.8, "Get_Sink_Cap Message") to discover which power levels can be utilized by the Consumer. 8.2.6 Use of "Unconstrained Power" bit with Batteries and AC supplies The Device Policy Manager in a Provider or Consumer May monitor the status of any variable sources of power that could have an impact on its Capabilities as a Source such as Batteries and AC supplies and reflect this in the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") provided as part of the Source_Capabilities or Sink_Capabilities Message (see Section 6.4.1, "Capabilities Message"). When monitored, and a USB interface is supported, the External Power status (see [UCSI]) and the Battery state (see Section 9.4.1, "GetBatteryStatus") Shall also be reported to the System Policy Manager using the USB interface. 8.2.6.1 AC Supplies The Unconstrained Power bit provided by Sources and Sinks (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") notifies a connected device that it is acceptable to use the Advertised power for charging as well as for what is needed for normal operation. A device that sets the Unconstrained Power bit has either an external source of power that is sufficient to adequately power the system while charging external devices or expects to charge external devices as a primary state of function (such as a battery pack). In the case of the external power source, the power can either be from an AC Supply directly connected to the device or from an AC Supply connected to an Attached device, which is also getting unconstrained power from its power supply. The Unconstrained Power bit is in this way communicated through a PD system indicating that the origin of the power is from a single or multiple AC supplies, from a battery bank, or similar:  If the "Unconstrained Power" bit is set, then that power is originally sourced from an AC Supply.  Devices capable of consuming on multiple ports can only claim that they have "Unconstrained Power" for the power Advertised as a Provider Port if there is unconstrained power beyond that needed for nor- mal operation coming from external supplies, (e.g., multiple AC supplies).  This concept applies as the power is routed through multiple Provider and Consumer tiers, so, as an ex- ample. Power provided out of a monitor that is connected to a monitor that gets power from an AC Sup- ply, will claim it has "Unconstrained Power" even though it is not directly connected to the AC Supply. An example use case is a Tablet computer that is used with two USB A/V displays that are daisy chained (see Figure 8.1, "Example of daisy chained displays"). The tablet and 1st display are not externally powered, (meaning, they have no source of power outside of USB PD). The 2nd display has an external supply Attached which could either be a USB PD based supply or some other form of external supply. When the displays are connected as shown, the power adapter Attached to the 2nd display is able to power both the 1st display and the tablet. In this case the 2nd display will indicate the presence of a sufficiently sized Charger to the 1st display, by setting its "Unconstrained Power" bit. The 1st display will then in turn assess and indicate the presence of the extra power to the tablet by setting its "Unconstrained Power" bit. Power is transmitted through the system to all devices, provided that there is sufficient power available from the external supply. Page 422 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.1 Example of daisy chained displays Another example use case is a laptop computer that is Attached to both an external supply and a Tablet computer. In this situation, if the external supply is large enough to power the laptop in its normal state as well as charge an external device, the laptop would set its "Unconstrained Power" bit and the tablet will allow itself to charge at its peak rate. If the external supply is small, however, and would not prevent the laptop from discharging if maximal power is drawn by the external device, the laptop would not set its "Unconstrained Power" bit, and the tablet can choose to draw less than what is offered. This amount could be just enough to prevent the tablet from discharging, or none at all. Alternatively, if the tablet determines that the laptop has significantly larger battery with more charge than the tablet has, the tablet can still choose to charge itself, although possibly not at the maximal rate. In this way, Sinks that do not receive the Unconstrained Power bit from the connected Source can still choose to charge their batteries, or charge at a reduced rate, if their policy determines that the impact to the Source is minimal -- such as in the case of a phone with a small battery charging from a laptop with a large battery. These policies can be decided via further USB PD communication. 8.2.6.2 Battery Supplies When monitored, and a USB interface is supported, the Battery state Shall be reported to the System Policy Manager using the USB interface. If the device is Battery-powered but is in a state that is primarily for charging external devices, the device is considered to be an unconstrained source of power and thus Should set the "Unconstrained Power" bit. A simplified algorithm is detailed below to ensure that Battery powered devices will get charge from non-Battery powered devices when possible, and also to ensure that devices do not constantly Power Role Swap back and forth. When two devices are connected that do not have Unconstrained Power, they Should define their own policies so as to prevent constant Power Role Swapping. This algorithm uses the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power"), thus the decisions are based on the availability and sufficiency of an external supply, not the full Capabilities of a system or device or product. Recommendations:  Provider/Consumers using large external sources ("Unconstrained Power" bit set) Should always deny Power Role Swap requests from Consumer/Providers not using external sources ("Unconstrained Pow- er" bit cleared). AC Tablet Display 1 Display 2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 423  Provider/Consumers not using large external sources ("Unconstrained Powered" bit cleared) Should al- ways accept a Power Role Swap request from a Consumer/Provider using large external power sources ("Unconstrained Power" bit set) unless the requester is not able to provide the requirements of the present Provider/Consumer. 8.2.7 Interface to the Policy Engine The Device Policy Manager Shall maintain an interface to the Policy Engine for each Port in the device. 8.2.7.1 Device Policy Manager in a Provider The Device Policy Manager in a Provider Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/ device Attachment status for a given cable.  Inform the Policy Engine whenever the Source Capabilities available for a Port change.  Evaluate requests from an Attached Consumer and provide responses to the Policy Engine.  Respond to requests for power supply transitions from the Policy Engine.  Indication to Policy Engine when power supply transitions are complete.  Maintain a power reserve for devices operating on a Port at less than maximum power. 8.2.7.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/device Attachment status.  Inform the Policy Engine whenever the power requirements for a Port change.  Evaluate Source Capabilities and provide suitable responses:  Request from offered Capabilities.  Indicate whether additional power is required.  Respond to requests for Sink transitions from the Policy Engine. 8.2.7.3 Device Policy Manager in a Dual-Role Power Device The Device Policy Manager in a Dual-Role Power Device Shall provide the following functions to the Policy Engine:  Provider Device Policy Manager  Consumer Device Policy Manager  Interface for the Policy Engine to request power supply transitions from Source to Sink and vice versa.  Indications to Policy Engine during Power Role Swap transitions. 8.2.7.4 Device Policy Manager in a Dual-Role Power Device Dead Bat- tery handling The Device Policy Manager in a Dual-Role Power Device with a Dead Battery Should:  Switch Ports to Sink-only or Sink DFP operation to obtain power from the next Attached Source.  Use VBUS from the Attached Source to power the USB Power Delivery communications as well as charging to enable the Negotiation of higher input power. Page 424 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3 Policy Engine 8.3.1 Introduction There is one Policy Engine instance per Port that interacts with the Device Policy Manager in order to implement the present Local Policy for that particular Port. This section includes:  AMSs for various operations.  State diagrams covering operation of Sources, Sinks and Cable Plugs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 425 8.3.2 Atomic Message Sequence Diagrams 8.3.2.1 Introduction The Policy Engine drives the Atomic Message Sequences (AMS) and responses based on both the expected AMSs and the present Local Policy. An AMS Shall be defined as a Message sequence that starts and/or ends in either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states (see Section 8.3.3.2, "Policy Engine Source Port State Diagram", Section 8.3.3.3, "Policy Engine Sink Port State Diagram" and Section 8.3.3.25, "Cable Plug Specific State Diagrams"). In addition, the Cable Plug discovery sequence specified in Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram" Shall be defined as an AMS. The Source and Sink indicate to the Protocol Layer when an AMS starts and ends on entry to/exit from PE_SRC_Ready or PE_SNK_Ready (see Section 8.3.3.2, "Policy Engine Source Port State Diagram" and Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). An AMS Shall be considered to have been started by the Initiator when the protocol engine signals the Policy Engine that transmission is a success (the GoodCRC Message has been received in response to the initial Message). For the receiving Port the AMS Shall be considered to have started when the initial Message has arrived. An AMS Shall be considered to have ended:  When the Protocol Layer signals the Policy Engine that transmission of the final Message in the AMS is a success and for the opposite Port when the final Message has been received.  A Soft_Reset Message, Hard Reset Signaling for SOP’ or SOP’’ or Cable Reset Signaling has been sent or received. Section 8.3.2.1.3, "Atomic Message Sequences" gives details of these AMS's. This section contains sequence diagrams that highlight some of the more interesting transactions. It is by no means a complete summary of all possible combinations but is Informative in nature. Page 426 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.1 Basic Message Exchange Figure 8.2, "Basic Message Exchange (Successful)" below illustrates how a Message is sent. Table 8.1, "Basic Message Flow" details the steps in the flow. Note that the sender might be either a Source or Sink while the receiver might be either a Sink or Source. The basic Message sequence is the same. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. Figure 8.2 Basic Message Exchange (Successful) Table 8.1 Basic Message Flow Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 7 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Protocol Layer checks and increments the MessageIDCounter and stops CRCReceiveTimer. 9 Protocol Layer informs the Policy Engine that the Message was successfully sent. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 427 8.3.2.1.2 Errors in Basic Message flow There are various points during the Message flow where failures in communication or other issues can occur. Figure 8.3, "Basic Message flow indicating possible errors" is an annotated version of Figure 8.2, "Basic Message Exchange (Successful)" indicating at which point issues can occur. Table 8.2, "Potential issues in Basic Message Flow" details the steps in the flow. Figure 8.3 Basic Message flow indicating possible errors Table 8.2 Potential issues in Basic Message Flow Point Possible issues A 1) There is an incoming Message on the channel meaning that the PHY Layer is unable to send. In this case the outgoing Message is removed from the queue and the incoming Message processed. 2) Due to some sort of noise on the line it is not possible to transmit. In this case the outgoing Message is Discarded by the PHY Layer. Retransmission is via the Protocol Layer’s normal mechanism. B 1) Message does not arrive at the PHY Layer due to noise on the channel. 2) Message arrives but has been corrupted and has a bad CRC. There is no Message to pass up to the Protocol Layer on the receiver which means a GoodCRC Message is not sent. This leads to a CRCReceiveTimer timeout in the Message Sender. C 1) MessageID of received Message matches stored MessageID so this is a retry. Message is not passed up to the Policy Engine. D 1) Policy Engine receives a known Message that it was not expecting. 2) Policy Engine receives an Unrecognized Message. These cases are errors in the protocol which could lead to the generation of a Soft_Reset Message. E Same as point A but at the Message Receiver side. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver • Message currently being received • Channel unavailable • Message does not arrive • Message has bad CRC • Message is a retry • Message is unexpected • Message is unknown • Message currently being received • Channel unavailable • GoodCRC does not arrive • GoodCRC has a bad CRC • GoodCRC has the wrong MessageID • Response is not GoodCRC A B C D E F G Page 428 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.4, "Basic Message Flow with Bad followed by a Retry" illustrates one of these cases; the basic Message flow with a retry due to a bad CRC at the Message Receiver. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. The Protocol Layer is responsible for retries on a “'n' strikes and you are out" basis (nRetryCount). Table 8.3, "Basic Message Flow with CRC failure" details the steps in the flow. Figure 8.4 Basic Message Flow with Bad followed by a Retry F 1) GoodCRC Message response does not arrive at the Message Sender side due to the noise on the channel. 2) GoodCRC Message response arrives but has a bad CRC. A GoodCRC Message is not received by the Message Sender’s Protocol Layer. This leads to a CRCReceiveTimer timeout in the Message Sender. G 1) GoodCRC Message is received but does contain the same MessageID as the transmitted Message. 2) A Message is received but it is not a GoodCRC Message (similar case to that of an unexpected or unknown Message but this time detected in the Protocol Layer). Both of these issues indicate errors in receiving an expected GoodCRC Message which will lead to a CRCReceiveTimer timeout in the Protocol Layer and a subsequent retry (except for communications with Cable Plugs). Table 8.2 Potential issues in Basic Message Flow Point Possible issues : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine 4: Message 5: Message + CRC 6: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 7: Message received Consume message 8: GoodCRC 9: GoodCRC + CRC 10: GoodCRC Check and increment MessageIDCounter Reset RetryCounter Stop CRCReceiveTimer 11: Message sent 1: Send message 2: Message 3: Message + CRC Start CRCReceiveTimer CRCReceiveTimer expires Retry and increment RetryCounter Message is not received or CRC is bad so message is not passed to the protocol layer Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 429 Table 8.3 Basic Message Flow with CRC failure Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives no Message or a Message with an incorrect CRC. Nothing is passed to Protocol Layer. 4 Since no response is received, the CRCReceiveTimer will expire and trigger the first retry by the Protocol Layer. The RetryCounter is incremented. Protocol Layer passes the Message to the PHY Layer. 5 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 6 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 7 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 8 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 9 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 10 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 11 Protocol Layer verifies the MessageID, stops CRCReceiveTimer and resets the RetryCounter. Protocol Layer informs the Policy Engine that the Message was successfully sent. Page 430 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3 Atomic Message Sequences The types of Atomic Message Sequences (AMS) are listed in Table 8.4, "Atomic Message Sequences". The following tables list sequences of either Messages or combinations of Messages and one or more embedded AMSes which are Non-interruptible. Where there is an embedded AMS the entire Message sequence is treated as an AMS and the Rp value used for Collision Avoidance (see Section 5.7, "Collision Avoidance") Shall only be changed on leaving or entering the ready state at the beginning or end of the entire Message sequence, and not at the start or end of the embedded AMS. Note: An AMS is has not started until the first Message in the sequence has been successfully sent (i.e., a GoodCRC Message has been received acknowledging the Message). Table 8.31, "AMS: Hard Reset" details a Hard Reset (which is Signaling not an AMS) followed by an SPR Contract Negotiation AMS which Shall be treated as Non-interruptible. Table 8.4 Atomic Message Sequences Type of AMS Table Reference Section Reference Power Negotiation (SPR) Table 8.5, "AMS: Power Negotiation (SPR)" Section 8.3.2.2.1 Power Negotiation (EPR) Table 8.6, "AMS: Power Negotiation (EPR)" Section 8.3.2.2.2 Unsupported Message Table 8.7, "AMS: Unsupported Message" Section 8.3.2.3 Soft Reset Table 8.8, "AMS: Soft Reset" Section 8.3.2.4 Data Reset Table 8.9, "AMS: Data Reset" Section 8.3.2.5 Hard Reset Table 8.31, "AMS: Hard Reset" Section 8.3.2.6 Power Role Swap Table 8.10, "AMS: Power Role Swap" Section 8.3.2.7 Fast Role Swap Table 8.11, "AMS: Fast Role Swap" Section 8.3.2.8 Data Role Swap Table 8.12, "AMS: Data Role Swap" Section 8.3.2.9 VCONN Swap Table 8.13, "AMS: VCONN Swap" Section 8.3.2.10 Alert Table 8.14, "AMS: Alert" Section 8.3.2.11.1 Status Table 8.15, "AMS: Status" Section 8.3.2.11.2 Source Capabilities/ Sink Capabilities (SPR) Table 8.16, "AMS: Source/Sink Capabilities (SPR)" Section 8.3.2.11.3.1 Source Capabilities/ Sink Capabilities (EPR) Table 8.17, "AMS: Source/Sink Capabilities (EPR)" Section 8.3.2.11.3.2 Extended Capabilities Table 8.18, "AMS: Extended Capabilities" Section 8.3.2.11.4 Battery Capabilities and Status Table 8.19, "AMS: Battery Capabilities" Section 8.3.2.11.5 Manufacturer Information Table 8.20, "AMS: Manufacturer Information" Section 8.3.2.11.6 Country Codes Table 8.21, "AMS: Country Codes" Section 8.3.2.11.7 Country Information Table 8.22, "AMS: Country Information" Section 8.3.2.11.8 Revision Information Table 8.23, "AMS: Revision Information" Section 8.3.2.11.9 Source Information Table 8.24, "AMS: Source Information" Section 8.3.2.11.10 Security Table 8.25, "AMS: Security" Section 8.3.2.12 Firmware Update Table 8.26, "AMS: Firmware Update" Section 8.3.2.13 Structured VDM Table 8.27, "AMS: Structured VDM" Section 8.3.2.14 Built-In Self-Test (BIST) Table 8.28, "AMS: Built-In Self-Test (BIST)" Section 8.3.2.15 Enter USB Table 8.29, "AMS: Enter USB" Section 8.3.2.16 Unstructured VDM Table 8.30, "AMS: Unstructured VDM" Section 8.3.2.17 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 431 8.3.2.1.3.1 AMS: Power Negotiation (SPR) Table 8.5 AMS: Power Negotiation (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref SPR Explicit Contract Negotiation (Accept) 1. Source_Capabilities Message 2. Request Message 3. Accept Message 4. PS_RDY Message Started by Source, SPR Mode Section 8.3.2.2.1.1.1 Section 8.3.3.2, Section 8.3.3.3 SPR Explicit Contract Negotiation (Reject) 1. Source_Capabilities Message 2. Request Message 3. Reject Message Section 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Wait) 1. Source_Capabilities Message 2. Request Message 3. Wait Message Section 8.3.2.2.1.1.3 SPR PPS Keep Alive 1. Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, SPR Mode Section 8.3.2.2.1.2 Section 8.3.3.3 SPR Sink Makes Request (Accept) 1. Request Message 2. Accept Message 3. PS_RDY Message Section 8.3.2.2.1.3.1 Section 8.3.3.2, Section 8.3.3.3 SPR Sink Makes Request (Reject) 1. Request Message 2. Reject Message Section 8.3.2.2.1.3.2 SPR Sink Makes Request (Wait) 1. Request Message 2. Wait Message Section 8.3.2.2.1.3.3 Page 432 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.2 AMS: Power Negotiation (EPR) Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Entering EPR Mode (Success) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS (Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Succeeded) Message 6. EPR Explicit Contract Negotiation AMS Started by Sink, SPR Mode Section 8.3.2.2.2.1, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3, Section 8.3.2.2.2.4 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1, Section 8.3.3.2, Section 8.3.3.3 Entering EPR Mode (Failure due to non-EPR Cable) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS(Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.2, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1 Entering EPR Mode (Failure of VCONN Swap) 1. EPR_Mode (Enter) Message. 2. EPR_Mode (Enter Acknowledge) Message. 3. VCONN Source Swap, initiated by non- VCONN Source (Reject) AMS(Optional). 4. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.3, Section 8.3.2.10.1, Section 8.3.2.10.2 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 433 EPR Explicit Contract Negotiation (Accept) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Accept Message 4. PS_RDY Message Started by Source, EPR Mode Section 8.3.2.2.2.2.1 Section 8.3.3.2, Section 8.3.3.3 EPR Explicit Contract Negotiation (Reject) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Reject Message Section 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Wait) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Wait Message Section 8.3.2.2.2.2.3 EPR Keep Alive 1. EPR_KeepAlive Message 2. EPR_KeepAlive_Ack Message Started by Sink, EPR Mode Section 8.3.2.2.2.3 Exiting EPR Mode (Sink Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Sink, EPR Mode Section 8.3.2.2.2.4.1, Section 8.3.2.2.1.1 Section 8.3.3.25.3, Section 8.3.3.25.4, Section 8.3.3.2, Section 8.3.3.3 Exiting EPR Mode (Source Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Source, EPR Mode Section 8.3.2.2.2.4.2, Section 8.3.2.2.1.1 EPR Sink Makes Request (Accept) 1. EPR_Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.1 Section 8.3.3.2, Section 8.3.3.3 EPR Sink Makes Request (Reject) 1. EPR_Request Message 2. Reject Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.2 EPR Sink Makes Request (Wait) 1. EPR_Request Message 2. Wait Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.3 Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Page 434 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.3 AMS: Unsupported Message 8.3.2.1.3.4 AMS: Soft Reset 8.3.2.1.3.5 AMS: Data Reset Table 8.7 AMS: Unsupported Message AMS Message Sequence Conditions AMS Ref State Machine Ref Unsupported Message 1. Any Message which is not supported by the Source or Sink 2. Not_Supported Message Started by Source or Sink Section 8.3.2.3 Section 8.3.3.6.2 Table 8.8 AMS: Soft Reset AMS Message Sequence Conditions AMS Ref State Machine Ref Soft Reset 1. Soft_Reset Message 2. Accept Message 3. In SPR Mode: SPR Explicit Contract Negotiation AMS 4. or in EPR Mode: EPR Explicit Contract Negotiation AMS. Started by Source or Sink Section 8.3.2.4, Section 8.3.2.2.1.1, Section 8.3.2.2.1.1, Section 8.3.2.2.2.2 Section 8.3.3.4.1, Section 8.3.3.4.2, Section 8.3.3.25.2.1, Section 8.3.3.25.2.3, Section 8.3.3.25.2.4, Section 8.3.3.2, Section 8.3.3.3 Table 8.9 AMS: Data Reset AMS Message Sequence Conditions AMS Ref State Machine Ref DFP Initiated Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.1 Section 8.3.3.5.1, Section 8.3.3.5.2 DFP Receives Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.2 DFP Initiated Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.3 DFP Receives Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 435 8.3.2.1.3.6 AMS: Power Role Swap 8.3.2.1.3.7 AMS: Fast Role Swap Table 8.10 AMS: Power Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.7.1.1, Section 8.3.2.2.1.1 Section 8.3.3.19.3, Section 8.3.3.19.4, Section 8.3.3.2, Section 8.3.3.3 Source Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.1.2 Source Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.1.1 Sink Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.7.2.1, Section 8.3.2.2.1.1 Sink Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.2.2 Sink Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.2.3 Table 8.11 AMS: Fast Role Swap AMS Message Sequence Conditio ns AMS Ref State Machine Ref Fast Role Swap 1. FR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.8, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3, Section 8.3.3.19.5, Section 8.3.3.19.6 Page 436 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.8 AMS: Data Role Swap Table 8.12 AMS: Data Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Data Role Swap, Initiated by UFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.1.1 Section 8.3.3.19.1, Section 8.3.3.19.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.2.3 Data Role Swap, Initiated by DFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.4.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 437 8.3.2.1.3.9 AMS: VCONN Swap 8.3.2.1.3.10 AMS: Alert Table 8.13 AMS: VCONN Swap AMS Message Sequence Conditions AMS Ref State Machine Ref VCONN Source Swap, initiated by VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by VCONN Source Section 8.3.2.10.1.1 Section 8.3.3.20 VCONN Source Swap, initiated by VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.1.3 VCONN Source Swap, initiated by non- VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by non-VCONN Source Section 8.3.2.10.2.1 VCONN Source Swap, initiated by non- VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.2.2 VCONN Source Swap, initiated by non- VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.2.3 Table 8.14 AMS: Alert AMS Message Sequence Conditions AMS Ref AMS Ref Source sends Alert to a Sink (SenderResponseTi mer Timeout) 1. Alert Message Started by Source Section 8.3.2.11.1.1 Section 8.3.3.7.1, Section 8.3.3.7.2 Source sends Alert to a Sink (Get_Status Message) 1. Alert Message 2. Sink Gets Source Status AMS Sink sends Alert to a Source (SenderResponseTi mer Timeout) 1. Alert Message Started by Sink Section 8.3.2.11.1.2 Section 8.3.3.7.3, Section 8.3.3.7.4 Sink sends Alert to a Source (Get_Status Message) 1. Alert Message 2. Source Gets Sink Status AMS Page 438 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.11 AMS: Status 8.3.2.1.3.12 AMS: Source/Sink Capabilities (SPR) Table 8.15 AMS: Status AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Status 1. Get_Status Message 2. Status Message Started by Sink Started by Source Section 8.3.2.11.2.1, Section 8.3.2.11.2.2 Section 8.3.3.10.1, Section 8.3.3.10.2 Source Gets Sink Status 1. Get_Status Message 2. Status Message VCONN Source Gets Cable Plug Status 1. Get_Status Message 2. Status Message Started by VCONN Source Started by Sink Section 8.3.2.11.2.3, Section 8.3.2.11.2.4 Sink Gets Source PPS Status 1. Get_PPS_Status Message 2. PPS_Status Message Section 8.3.3.10.3, Section 8.3.3.10.4 Table 8.16 AMS: Source/Sink Capabilities (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Capabilities (EPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Sink Section 8.3.2.11.3.1.1, Section 8.3.2.2.1.3.1, Section 8.3.2.2.1.3.2, Section 8.3.2.2.1.3.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets Source Capabilities (Accept in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Accept) AMS Sink Gets Source Capabilities (Reject in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Reject) AMS Sink Gets Source Capabilities (Wait in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Source Section 8.3.2.11.3.1.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink Capabilities 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Source Section 8.3.2.11.3.1.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.1.4 Section 8.3.3.19.9, Section 8.3.3.19.8 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 439 8.3.2.1.3.13 AMS: Source/Sink Capabilities (EPR) Table 8.17 AMS: Source/Sink Capabilities (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets EPR Source Capabilities (SPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Sink Section 8.3.2.11.3.2.1, Section 8.3.2.2.2.5.1, Section 8.3.2.2.2.5.2, Section 8.3.2.2.2.5.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets EPR Source Capabilities (Accept in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Accept) AMS Sink Gets EPR Source Capabilities (Reject in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Reject) AMS Sink Gets EPR Source Capabilities (Wait in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power EPR Sink 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Source Section 8.3.2.11.3.2.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink EPR Capabilities 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Source Section 8.3.2.11.3.2.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink EPR Capabilities from a Dual-Role Power Source 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.2.4 Section 8.3.3.19.8, Section 8.3.3.19.9 Page 440 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.14 AMS: Extended Capabilities 8.3.2.1.3.15 AMS: Battery Capabilities Table 8.18 AMS: Extended Capabilities AMS Interruptible Message Sequence Conditions AMS Ref Sink Gets Source Extended Capabilities 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.4.1 Section 8.3.3.8.1, Section 8.3.3.8.2 Dual-Role Power Source Gets Source Extended Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.4.2 Section 8.3.3.19.11, Section 8.3.3.19.12 Source Gets Sink Extended Capabilities 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Source Section 8.3.2.11.4.3 Section 8.3.3.8.3, Section 8.3.3.8.4 Dual-Role Power Sink Gets Sink Extended Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Sink Section 8.3.2.11.4.4 Section 8.3.3.19.13, Section 8.3.3.19.14 Table 8.19 AMS: Battery Capabilities AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Sink Section 8.3.2.11.5.1 Section 8.3.3.11.1, Section 8.3.3.11.2 Source Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Source Section 8.3.2.11.5.2 Sink Gets Battery Status 1. Get_Battery_Status Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.3 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Battery Status 1. Get_Battery_Cap Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 441 8.3.2.1.3.16 AMS: Manufacturer Information 8.3.2.1.3.17 AMS: Country Codes 8.3.2.1.3.18 AMS: Country Information Table 8.20 AMS: Manufacturer Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Port Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.1 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Port Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.2 Source Gets Battery Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.3 Sink Gets Battery Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.4 VCONN Source Gets Manufacturer Information from a Cable Plug 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by VCONN Source Section 8.3.2.11.6.5 Table 8.21 AMS: Country Codes AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Codes from a Sink 1. Get_Country_Codes Message 2. Country_Codes Message Started by Source Section 8.3.2.11.7.1 Section 8.3.3.14.1, Section 8.3.3.14.2 Sink Gets Country Codes from a Source 1. Get_Country_Codes Message 2. Country_Codes Message Started by Sink Section 8.3.2.11.7.2 VCONN Source Gets Country Codes from a Cable Plug 1. Get_Country_Codes Message 2. Country_Codes Message Started by VCONN Source Section 8.3.2.11.7.3 Table 8.22 AMS: Country Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Information from a Sink 1. Get_Country_Info Message 2. Country_Info Message Started by Source Section 8.3.2.11.8.1 Section 8.3.3.14.3, Section 8.3.3.14.4 Sink Gets Country Information from a Source 1. Get_Country_Info Message 2. Country_Info Message Started by Sink Section 8.3.2.11.8.2 VCONN Source Gets Country Information from a Cable Plug 1. Get_Country_Info Message 2. Country_Info Message Started by VCONN Source Section 8.3.2.11.8.3 Page 442 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.19 AMS: Revision Information 8.3.2.1.3.20 AMS: Source Information 8.3.2.1.3.21 AMS: Security Table 8.23 AMS: Revision Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Revision Information from a Sink 1. Get_Revision Message 2. Revision Message Started by Source Section 8.3.2.11.9.1 Section 8.3.3.15.1, Section 8.3.3.15.2 Sink Gets Revision Information from a Source 1. Get_Revision Message 2. Revision Message Started by Sink Section 8.3.2.11.9.2 VCONN Source Gets Revision Information from a Cable Plug 1. Get_Revision Message 2. Revision Message Started by VCONN Source Section 8.3.2.11.9.1 Table 8.24 AMS: Source Information AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Information 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.10.1 Section 8.3.3.9.1, Section 8.3.3.9.2 Dual-Role Power Source Gets Source Information from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.10.2 Section 8.3.3.19.15, Section 8.3.3.19.16 Table 8.25 AMS: Security AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests security exchange with Sink 1. Security_Request Message Started by Source Section 8.3.2.12.1 Section 8.3.3.17.1, Section 8.3.3.17.2, Section 8.3.3.17.3 Sink requests security exchange with Source 1. Security_Request Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Request Message Started by VCONN Source Section 8.3.2.12.3 Source responds to security exchange with Sink 1. Security_Response Message Started by Source Section 8.3.2.12.1 Sink responds to security exchange with Source 1. Security_Response Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Response Message Started by VCONN Source Section 8.3.2.12.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 443 8.3.2.1.3.22 AMS: Firmware Update Table 8.26 AMS: Firmware Update AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests firmware update exchange with Sink 1. Firmware_Update_Request Message Started by Source Section 8.3.2.13.1 Section 8.3.3.18.1, Section 8.3.3.18.2, Section 8.3.3.18.3 Sink requests firmware update exchange with Source 1. Firmware_Update_Request Message Started by Sink Section 8.3.2.13.2 VCONN Source requests firmware update exchange with Cable Plug 1. Firmware_Update_Request Message Started by VCONN Source Section 8.3.2.13.3 Source responds to firmware update exchange with Sink 1. Firmware_Update_Response Message Started by Source Section 8.3.2.13.1 Sink responds to firmware update exchange with Source 1. Firmware_Update_Response Message Started by Sink Section 8.3.2.13.2 VCONN Source responds to firmware update exchange with Cable Plug 1. Firmware_Update_Response Message Started by VCONN Source Section 8.3.2.13.3 Page 444 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.23 AMS: Structured VDM Table 8.27 AMS: Structured VDM AMS Message Sequence Conditions AMS Ref State Machine Ref Initiator to Responder Discover Identity (ACK) 1. Discover Identity REQ Command 2. Discover Identity ACK Command Started by Initiator Section 8.3.2.14.1.1 Section 8.3.3.21.1, Section 8.3.3.22.1 Initiator to Responder Discover Identity (NAK) 1. Discover Identity REQ Command 2. Discover Identity NAK Command Section 8.3.2.14.1.2 Initiator to Responder Discover Identity (BUSY) 1. Discover Identity REQ Command 2. Discover Identity BUSY Command Section 8.3.2.14.1.3 Initiator to Responder Discover SVIDs (ACK) 1. Discover SVIDs REQ Command 2. Discover SVIDs ACK Command Section 8.3.2.14.2.1 Section 8.3.3.21.2, Section 8.3.3.22.2 Initiator to Responder Discover SVIDs (NAK) 1. Discover SVIDs REQ Command 2. Discover SVIDs NAK Command Section 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (BUSY) 1. Discover SVIDs REQ Command 2. Discover SVIDs BUSY Command Section 8.3.2.14.2.3 Initiator to Responder Discover Modes (ACK) 1. Discover Modes REQ Command 2. Discover Modes ACK Command Section 8.3.2.14.3.1 Section 8.3.3.21.3, Section 8.3.3.22.3 Initiator to Responder Discover Modes (NAK) 1. Discover Modes REQ Command 2. Discover Modes NAK Command Section 8.3.2.14.3.2 Initiator to Responder Discover Modes (BUSY) 1. Discover Modes REQ Command 2. Discover Modes BUSY Command Section 8.3.2.14.3.3 DFP to UFP Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Started by DFP Section 8.3.2.14.4.1 Section 8.3.3.23.1, Section 8.3.3.24.1 DFP to UFP Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.2 Section 8.3.3.23.2, Section 8.3.3.24.2 DFP to Cable Plug Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Section 8.3.2.14.4.3 Section 8.3.3.23.1, Section 8.3.3.25.4.1 DFP to Cable Plug Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.4 Section 8.3.3.23.2, Section 8.3.3.25.4.2 Initiator to Responder Attention 1. Attention REQ Command Started by Initiator Section 8.3.2.14.4.5 Section 8.3.3.21.4, Section 8.3.3.22.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 445 8.3.2.1.3.24 AMS: Built-In Self-Test (BIST) 8.3.2.1.3.25 AMS: Enter USB 8.3.2.1.3.26 AMS: Unstructured VDM Table 8.28 AMS: Built-In Self-Test (BIST) AMS Message Sequence Conditions AMS Ref State Machine Ref BIST Carrier Mode 1. BIST (BIST Carrier Mode) Message Started by Tester Section 8.3.2.15.1 Section 8.3.3.27.1 BIST Test Data Mode 1. BIST (BIST Test Data) Message Section 8.3.2.15.2 Section 8.3.3.27.2 BIST Shared Capacity Test Mode 1. BIST (BIST Shared Test Mode Entry) Message 2. Series of Messages 3. BIST (BIST Shared Test Mode Exit) Message Section 8.3.2.15.3 Section 8.3.3.27.3 Table 8.29 AMS: Enter USB AMS Message Sequence Conditions AMS Ref State Machine Ref UFP Entering USB4® Mode (Accept) 1. Enter_USB Message 2. Accept Message Started by DFP Section 8.3.2.16.1.1 Section 8.3.3.16.1, Section 8.3.3.16.2 UFP Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.1.2 UFP Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.1.3 Cable Plug Entering USB4 Mode (Accept) 1. Enter_USB Message 2. Accept Message Section 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.2.3 Table 8.30 AMS: Unstructured VDM AMS Message Sequence AMS Ref State Machine Ref Unstructured VDM 1. Unstructured Vendor_Defined Message Section 8.3.2.17.1 VDEM 1. Vendor_Defined_Extended Message Section 8.3.2.17.2 Page 446 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.27 AMS: Hard Reset Table 8.31 AMS: Hard Reset AMS Interruptibl e Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.1, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3 Sink Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.6.2, Section 8.3.2.2.1.1 Source Initiated Hard Reset – Sink Long Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.3, Section 8.3.2.2.1.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 447 8.3.2.2 Power Negotiation 8.3.2.2.1 SPR 8.3.2.2.1.1 SPR Explicit Contract Negotiation 8.3.2.2.1.1.1 SPR Explicit Contract Negotiation (Accept) Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through 5 distinct phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  For SPR PPS operation:  the Source starts its keep alive timer.  the Sink starts its request timer to send periodic Request Messages. Page 448 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.5 Successful Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer For PPS operation start PPSRequestTimer New Power level Evaluate Capabilities Detect plug type Evaluate Request Prepare for new power Source Sink Cable Capabilities detected Plug type detected For PPS operation start PPSTimeoutTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 449 Table 8.32, "Steps for a successful Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.32 Steps for a successful Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 450 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.32 Steps for a successful Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 451 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. New Power Level Negotiated Table 8.32 Steps for a successful Power Negotiation Step Source Sink Page 452 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Reject) Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Reject Message. Figure 8.6 Rejected Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 453 Table 8.33, "Steps for a rejected Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 454 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 455 8.3.2.2.1.1.3 SPR Explicit Contract Negotiation (Wait) Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Wait Message. Figure 8.7 Wait response to Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Page 456 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.34, "Steps for a Wait response to a Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 457 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink Page 458 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.2 SPR PPS Keep Alive This is an example of SPR PPS keep alive operation during an Explicit Contract with SPR PPS as the APDO. Figure 8.8, "SPR PPS Keep Alive" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.8 SPR PPS Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer Stop PPSCommTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer Stop PPSRequestTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Send Ping if required to maintain activity Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer Start PPSRequestTimer New Power level Evaluate Request Prepare for new power Source Sink PPSRequestTimer Timeout Start PPSCommTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 459 Table 8.35, "Steps for SPR PPS Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.8, "SPR PPS Keep Alive" above. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink 1 The SinkPPSPeriodicTimer times out in the Policy Engine. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourcePPSCommTimer. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Page 460 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 27 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 461 8.3.2.2.1.3 SPR Sink Makes Request 8.3.2.2.1.3.1 SPR Sink Makes Request (Accept) This is an example of SPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.9, "SPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.9 SPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate Request Prepare for new power Source Sink Page 462 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.36, "Steps for SPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.9, "SPR Sink Makes Request (Accept)" above. Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 463 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink Page 464 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.3.2 SPR Sink Makes Request (Reject) This is an example of SPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.10, "SPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.10 SPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 465 Table 8.37, "Steps for SPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.10, "SPR Sink Makes Request (Reject)" above. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 466 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 467 8.3.2.2.1.3.3 SPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.11, "SPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.11 SPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate Request Source Sink Page 468 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.38, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.11, "SPR Sink Makes Request (Wait)" above. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 469 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 470 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2 EPR 8.3.2.2.2.1 Entering EPR Mode 8.3.2.2.2.1.1 Entering EPR Mode (Success) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process succeeds. Figure 8.12, "Entering EPR Mode (Success)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.12 Entering EPR Mode (Success) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode entered Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is EPR Capable 21: Send EPR_Mode (Enter Succeeded) 22: EPR_Mode (Enter Succeeded) 23: EPR_Mode (Enter Succeeded) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Succeeded) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Succeeded) 25: EPR_Mode (Enter Succeeded) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 471 Table 8.39, "Steps for Entering EPR Mode (Success)" below provides a detailed explanation of what happens at each labeled step in Figure 8.12, "Entering EPR Mode (Success)" above. Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter)Source_Capabilities Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 472 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source is now the VCONN Source and has determined that the Sink and the cable are EPR Capable. The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Succeeded) Message. 22 Protocol Layer creates the EPR_Mode (Enter Succeeded) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Succeeded) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Succeeded) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Succeeded) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Succeeded) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Entered Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 473 8.3.2.2.2.1.2 Entering EPR Mode (Failure due to non-EPR cable) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to the cable not being capable of EPR. Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.13 Entering EPR Mode (Failure due to non-EPR cable) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is not EPR Capable 21: Send EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) 23: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Failed) 25: EPR_Mode (Enter Failed) received Page 474 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.40, "Steps for Entering EPR Mode (Failure due to non-EPR cable)" below provides a detailed explanation of what happens at each labeled step in Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" above. Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 475 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR; cable is not EPR Capable. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 22 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source Page 476 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.1.3 Entering EPR Mode (Failure of VCONN Swap) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to a failure of the VCONN Swap process. Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.14 Entering EPR Mode (Failure of VCONN Swap) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source fails to become VCONN Source 20: Send EPR_Mode (Enter Failed) 21: EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 25: GoodCRC 26: GoodCRC + CRC 27: GoodCRC 28: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 23: EPR_Mode (Enter Failed) 24: EPR_Mode (Enter Failed) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 477 Table 8.41, "Steps for Entering EPR Mode (Failure of VCONN Swap)" below provides a detailed explanation of what happens at each labeled step in Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" above. Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 478 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". In this case the VCONN Swap process fails. 20 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 21 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 22 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 23 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 24 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 25 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 26 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 27 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 28 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 479 8.3.2.2.2.2 EPR Explicit Contract Negotiation 8.3.2.2.2.2.1 EPR Explicit Contract Negotiation (Accept) Figure 8.15, "Successful Fixed EPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  the Source starts its keep alive timer  the Sink starts its request timer to send periodic EPR_KeepAlive Messages Page 480 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.15 Successful Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer Start SinkEPRKeepAliveTimer New Power level Evaluate EPR Capabilities Evaluate EPR Request Prepare for new power Source Sink Cable EPR_Source_Capabilities detected Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 481 Table 8.42, "Steps for a successful EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.15, "Successful Fixed EPR Power Negotiation" above. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 482 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 483 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. The Policy Engine starts the SinkEPRKeepAliveTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in EPR operation the Policy Engine starts the SourceEPRKeepAliveTimer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Page 484 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Reject) Figure 8.16, "Rejected Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Reject Message. Figure 8.16 Rejected Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 485 Table 8.43, "Steps for a Rejected EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.16, "Rejected Fixed EPR Power Negotiation" above. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 486 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 487 8.3.2.2.2.2.3 EPR Explicit Contract Negotiation (Wait) Figure 8.17, "Wait response to Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Wait Message. Figure 8.17 Wait response to Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Page 488 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.44, "Steps for a Wait response to an EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.17, "Wait response to Fixed EPR Power Negotiation" above. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 489 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink Page 490 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.3 EPR Keep Alive This is an example of keep alive operation during an Explicit Contract in EPR Mode. Figure 8.18, "EPR Keep Alive"shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.18 EPR Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_KeepAlive 2: EPR_KeepAlive 3: EPR_KeepAlive + CRC 4: EPR_KeepAlive Check MessageID against local copy Store copy of MessageID 5: EPR_KeepAlive received Stop SourceEPRKeepAliveTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_KeepAlive sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send EPR_KeepAlive_Ack 11: EPR_KeepAlive_Ack 12: EPR_KeepAlive_Ack + CRC 13: EPR_KeepAlive_Ack Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: EPR_KeepAlive_Ack received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: EPR_KeepAlive_Ack sent Stop SenderResponseTimer Start SinkEPRKeepAliveTimer EPR Mode Continues Evaluate EPR_KeepAlive Source Sink SinkEPRKeepAliveTimer Timeout Stop SinkEPRKeepAliveTimer Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 491 Table 8.45, "Steps for EPR Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.18, "EPR Keep Alive" above. Table 8.45 Steps for EPR Keep Alive Step Source Sink 1 The SinkEPRKeepAliveTimer times out in the Policy Engine. The Policy Engine stops the SinkEPRKeepAliveTimer timer and tells the Protocol Layer to form an EPR_KeepAlive Message. 2 The Protocol Layer creates the EPR_KeepAlive Message and passes it to PHY Layer. The Protocol Layer. 3 PHY Layer receives the EPR_KeepAlive Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_KeepAlive Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourceEPRKeepAliveTimer. 6 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 9 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the SinkEPRKeepAliveTimer Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM to evaluate the SourceEPRKeepAliveTimer Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an EPR_KeepAlive_Ack Message. 11 The Protocol Layer forms the EPR_KeepAlive_Ack Message that is passed to the PHY Layer. 12 PHY Layer appends CRC and sends the EPR_KeepAlive_Ack Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_KeepAlive_Ack Message and compares the CRC it calculated with the one sent to verify the Message. 13 PHY Layer forwards the EPR_KeepAlive_Ack Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the SinkEPRKeepAliveTimer. Page 492 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 18 The Protocol Layer informs the Policy Engine that an EPR_KeepAlive_Ack Message was successfully sent. The Policy Engine starts the SourceEPRKeepAliveTimer. EPR Mode Continues Table 8.45 Steps for EPR Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 493 8.3.2.2.2.4 Exiting EPR Mode 8.3.2.2.2.4.1 Exiting EPR Mode (Sink Initiated) This is an example of an Exit EPR Mode operation where the Sink requests EPR Mode to be exited. Figure 8.19, "Exiting EPR Mode (Sink Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.19 Exiting EPR Mode (Sink Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Page 494 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.46, "Steps for Exiting EPR Mode (Sink Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.19, "Exiting EPR Mode (Sink Initiated)" above. Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 495 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source Page 496 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.4.2 Exiting EPR Mode (Source Initiated) This is an example of an Exit EPR Mode operation where the Source requests EPR Mode to be exited. Figure 8.20, "Exiting EPR Mode (Source Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.20 Exiting EPR Mode (Source Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 497 Table 8.47, "Steps for Exiting EPR Mode (Source Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.20, "Exiting EPR Mode (Source Initiated)" above. Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. Starts CRCReceiveTimer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Page 498 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 499 8.3.2.2.2.5 EPR Sink Makes Request 8.3.2.2.2.5.1 EPR Sink Makes Request (Accept) This is an example of EPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.21, "EPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.21 EPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate EPR_Request Prepare for new power Source Sink Page 500 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.48, "Steps for EPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.21, "EPR Sink Makes Request (Accept)" above. Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 501 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink Page 502 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.5.2 EPR Sink Makes Request (Reject) This is an example of EPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.22, "EPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.22 EPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 503 Table 8.49, "Steps for EPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.22, "EPR Sink Makes Request (Reject)" above. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 504 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 505 8.3.2.2.2.5.3 EPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.23, "EPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.23 EPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Page 506 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.50, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.23, "EPR Sink Makes Request (Wait)" above. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 507 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 508 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.3 Unsupported Message This is an example of the response to an Unsupported Message. Figure 8.24, "Unsupported message" shows the Messages as they flow across the bus and within the devices. Figure 8.24 Unsupported message : Protocol 1: Send Message : PHY : PHY : Protocol 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer 5: Message received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Message sent Start SenderResponseTimer 10: Send Not_supported 11: Not_supported 12: Not_supported + CRC 13: Not_supported 14: Not_supported received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Not_supported sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Message Initiator Message Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 509 Table 8.51, "Steps for an Unsupported Message" below provides a detailed explanation of what happens at each labeled step in Figure 8.24, "Unsupported message" above. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder 1 The Policy Engine directs the Protocol Layer to generate a Message. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Not_Supported Message. 11 Protocol Layer creates the Not_Supported Message and passes to PHY Layer. 12 PHY Layer receives the Not_Supported Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Not_Supported Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Not_Supported Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 510 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Not_Supported Message was successfully sent. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 511 8.3.2.4 Soft Reset This is an example of a Soft Reset operation. Figure 8.25, "Soft Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Soft Reset. Figure 8.25 Soft Reset : Protocol 1: Send Soft Reset : PHY : PHY : Protocol 2: Soft Reset 3: Soft Reset + CRC 4: Soft Reset Start CRCReceiveTimer 5: Soft Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Soft Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Reset Complete, Explicit Contract negotiation Reset Initiator Reset Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 512 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.52, "Steps for a Soft Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.25, "Soft Reset" above. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder 1 The Policy Engine directs the Protocol Layer to generate a Soft_Reset Message to request a Soft Reset. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Soft_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Soft_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Soft_Reset Message to the Protocol Layer. 5 Protocol Layer does not check the MessageID in the incoming Message and resets MessageIDCounter, stored MessageID and RetryCounter. The Protocol Layer forwards the received Soft_Reset Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Soft_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 513 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The reset is complete and protocol communication can restart. Port Partners perform an Explicit Contract Negotiation to re- synchronize their state machines. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder Page 514 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5 Data Reset 8.3.2.5.1 DFP Initiated Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP is also the VCONN Source and initiates a Data Reset. Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.26 DFP Initiated Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Tell DPM to perform Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete Start CRCReceiveTimer 23: Data_Reset_Complete received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 515 Table 8.53, "Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" above. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to perform a Data Reset. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 516 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The Data Reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 517 8.3.2.5.2 DFP Receives Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and is the VCONN Source. Figure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.27 DFP Receives Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Tell DPM to perform a Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete 23: Data_Reset_Complete received Inform DPM Data Reset is complete 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Page 518 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.54, "Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource" below provides a detailed explanation of what happens at each labeled step in FFigure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" above. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 519 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the DPM to perform a Data Reset. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Page 520 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.3 DFP Initiated Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP initiates a Data Reset and the UFP is the VCONN Source. Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.28 DFP Initiated Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Start VCONNDischargeTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset Request DPM to turn off VCONN DPM indicates VCONN is off 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete Start CRCReceiveTimer 32: Data_Reset_Complete received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 521 Table 8.55, "Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" above. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and starts the VCONNDischargeTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 522 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests the DPM to turn off VCONN. 19 When the DPM indicates VCONN has been turned off the Policy Engine tells the Protocol Layer to form an PS_RDY Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 22 Protocol Layer stores the MessageID of the incoming Message. 23 The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and tells the DPM to perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 523 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Page 524 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.4 DFP Receives Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and the UFP is the VCONN Source. Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.29 DFP Receives a Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer Tell DPM to turn off VCONN. 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Start VCONNDischargeTimer DPM indicates that VCONN has been turned off. 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete 32: Data_Reset_Complete received Inform DPM Data Reset is complete 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 525 Table 8.56, "Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" above. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to turn off VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 526 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNDischargeTimer. 19 When the DPM indicates that VCONN has been turned off the Policy Engine directs the Protocol Layer to generate a PS_RDY Message to request a Soft Reset. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and requests the DPM perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 527 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Page 528 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6 Hard Reset The following sections describe the steps required for a USB Power Delivery Hard Reset. The Hard Reset returns the operation of the USB Power Delivery to default Power Role/Data Role and operating voltage/current. During the Hard Reset USB Power Delivery PHY Layer communications Shall be disabled preventing communication between the Port Partner. Note: Hard Reset, in this case, is applied to the USB Power Delivery capability of an individual Port on which the Hard Reset is requested. A side effect of the Hard Reset is that it might reset other functions on the Port such as USB. 8.3.2.6.1 Source Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Source. Figure 8.30, "Source initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.30 Source initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink Hard Reset Complete Reset MessageIDCounter and RetryCounter Reset MessageIDCounter and RetryCounter 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN 9: Hard Reset Complete Channel enabled Channel enabled 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN Channel disabled Channel disabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 529 Table 8.57, "Steps for Source initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.30, "Source initiated Hard Reset" above. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter and RetryCounter. 5 The Protocol Layer informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation. and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Page 530 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 531 8.3.2.6.2 Sink Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Sink. Figure 8.31, "Sink Initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.31 Sink Initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 9: Hard Reset Complete Channel enabled 2: Send Hard Reset 5: Hard Reset received Channel enabled Page 532 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.58, "Steps for Sink initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.31, "Sink Initiated Hard Reset" above. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 533 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink Page 534 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6.3 Source Initiated Hard Reset - Sink Long Reset This is an example of a Hard Reset operation when initiated by a Source. In this example the Sink is slow responding to the reset causing the Source to send multiple Source_Capabilities Messages before it receives a GoodCRC Message response. Figure 8.32, "Source initiated reset - Sink long reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.32 Source initiated reset - Sink long reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 6: Power Supply Reset 11: Power Sink Reset 13: Send Capabilities 14: Capabilities 15: Capabilities + CRC 16: Capabilities Start CRCReceiveTimer Store copy of MessageID 17: Capabilities received 18: GoodCRC 19: GoodCRC + CRC 20: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 21: Capabilities sent Stop SourceCapabilitiesTimer Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 8: Send Capabilities 9: Capabilities 10: Capabilities + CRC Run SourceCapabilityTimer Send Capabilities messages until GoodCRC response is received. 12: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 7: Hard Reset Complete Channel enabled Channel enabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 535 Table 8.59, "Steps for Source initiated Hard Reset - Sink long reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.32, "Source initiated reset - Sink long reset" above. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 8 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Policy Engine starts the SourceCapabilityTimer. The SourceCapabilityTimer times out one or more times until a GoodCRC Message response is received. 9 Protocol Layer creates the Message and passes to PHY Layer. 10 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. Note: Source_Capabilities Message not received since channel is disabled. 11 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. Page 536 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 12 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 13 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Starts the SourceCapabilityTimer. 14 Protocol Layer creates the Message and passes to PHY Layer. 15 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 16 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 17 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 18 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 19 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 20 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 21 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the SourceCapabilityTimer, stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 537 8.3.2.7 Power Role Swap 8.3.2.7.1 Source Initiated Power Role Swap 8.3.2.7.1.1 Source Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap sequence. Page 538 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.33 Successful Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply stops sourcing power CC -> Rd 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Tell Power Supply to stop sourcing power Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Sink to start sinking power Reset Protocol Layer New Power Roles Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 539 Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" above. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine requests its power supply to stop supplying power and stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 540 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the PSSourceOffTimer and tells the power supply to stop sinking current. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Message to Sink, creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 541 30 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Page 542 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.1.2 Source Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  An Reject Message in response to the PR_Swap Message. Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.34 Rejected Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 543 Table 8.61, "Steps for a Rejected Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" above. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 544 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 545 8.3.2.7.1.3 Source Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, with a wait response, initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.35 Power Role Swap Sequence with wait Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 546 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.62, "Steps for a Source Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" above. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 547 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port Page 548 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2 Sink Initiated Power Role Swap 8.3.2.7.2.1 Sink Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 549 Figure 8.36 Successful Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Supply to start sinking power Reset Protocol Layer Tell Power Supply to stop sourcing power Power Supply stops sourcing power CC -> Rd Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 550 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" above. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer and tells the power supply to stop sinking current. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 551 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the power supply to stop supplying power. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 552 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer, informs the power supply that it can start consuming power. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 553 8.3.2.7.2.2 Sink Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Reject Message in response to the PR_Swap Message. Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.37 Rejected Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 554 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.64, "Steps for a Rejected Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" above. Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 555 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 556 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2.3 Sink Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, responded to with wait, initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.38 Power Role Swap Sequence with wait Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 557 Table 8.65, "Steps for a Sink Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" above. Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 558 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Wait Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 559 8.3.2.8 Fast Role Swap This is an example of a successful Fast Role Swap operation initiated by a Port that is initially a Source and therefore has Rp pulled up on its CC wire and which has lost power and needs to get vSafe5V quickly. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are several distinct phases to the Fast Role Swap Negotiation:  The Initial Source stops driving its power output which starts transitioning to vSafe0V and send the Fast Role Swap Request on the CC wire; these could occur in either order or simultaneously.  The Initial Sink stops sinking power. At this point the New Source still has Rd asserted and the New Sink still has Rp asserted.  An FR_Swap Message is sent by the New Source within tFRSwapInit of detecting the Fast Swap signal.  An Accept Message is sent by the New Sink in response to the FR_Swap Message.  The New Sink asserts Rd and sends a PS_RDY Message indicating that the voltage on VBUS is at or below vSafe5V.  The New Source asserts Rp and sends a PS_RDY Message indicating that it is acting as a Source and is sup- plying vSafe5V. Note: The New Source can start applying VBUS when VBUS is at or below vSafe5V (max) but will start driving VBUS to vSafe5V no later than tSrcFRSwap after detecting both the Fast Role Swap Request and that VBUS has dropped below vSafe5V (min). Figure 8.39, "Successful Fast Role Swap Sequence" shows the Messages as they flow across the bus and within the devices to accomplish the Fast Role Swap. Page 560 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.39 Successful Fast Role Swap Sequence : Protocol 1: Send FR_Swap : PHY : PHY : Protocol 2:FR_Swap 3: FR_Swap + CRC 4: FR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: FR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:FR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate FR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Stop PSSourceOnTimer Reset Protocol Layer Power Supply acting as a Sink and VBUS at or below vSafe5V CC -> Rd vSafe5V is being sourced by the new Source Stop PSSourceOffTimer CC -> Rp New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Tell Power Supply to Stop sourcing power and switch to Sink operation Signal Fast Swap on the CC Wire Fast Role Swap signal detected on CC Wire Tell Power Supply to stop sinking current. Fast Swap signal (CC driven to Gnd through rFRSwapTx or rFRSwapCableTx) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 561 Table 8.66, "Steps for a Successful Fast Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.39, "Successful Fast Role Swap Sequence" above. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. The DPM detects Fast Swap on the CC wire and tells the power supply to stop sinking current. The Policy Engine directs the Protocol Layer to send an FR_Swap Message within tFRSwapInit of detecting the Fast Swap signal. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. The DPM tells the Power Supply to stop sourcing power and switch to Sink operation. The DPM signals Fast Swap on the CC wire by driving CC to ground with a resistance of less than rFRSwapTx for at least tFRSwapTx. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the FR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the FR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received FR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the FR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer. Page 562 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The Policy Engine determines its power supply is no longer supplying VBUS and is acting as a Sink. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 563 28 The Policy Engine directs the DPM to apply the Rp pull up. Note: At some point (either before or after receiving the PS_RDY Message) the New Source has ap- plied vSafe5V no later than tSrcFRSwap after detecting the Fast Role Swap Request and that VBUS has dropped below vSafe5V. Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Fast Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Page 564 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9 Data Role Swap 8.3.2.9.1 Data Role Swap, Initiated by UFP Operating as Sink 8.3.2.9.1.1 Data Role Swap, Initiated by UFP Operating as Sink (Accept) Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.40 Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 565 Table 8.67, "Steps for Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" above. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 566 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 567 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.41 Rejected Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Page 568 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.68, "Steps for Rejected Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" above. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 569 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Page 570 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Sink (Wait) Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.42 Data Role Swap with Wait, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 571 Table 8.69, "Steps for Data Role Swap with Wait, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" above. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 572 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 573 8.3.2.9.2 Data Role Swap, Initiated by UFP Operating as Source 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Accept) Figure 8.43, "Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.43 Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 574 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.70, "Steps for Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.43, "Data Role Swap, UFP operating as Source initiates" above. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 575 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), and Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and still operating as a Sink (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 576 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Reject) Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.44 Rejected Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 577 Table 8.71, "Steps for Rejected Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" above. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 578 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 579 8.3.2.9.2.3 Data Role Swap, Initiated by UFP Operating as Source (Wait) Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.45 Data Role Swap with Wait, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Page 580 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.72, "Steps for Data Role Swap with Wait, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" above. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 581 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 582 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3 Data Role Swap, Initiated by DFP Operating as Source 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Accept) Figure 8.46, "Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.46 Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 583 Table 8.73, "Steps for Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.46, "Data Role Swap, DFP operating as Source initiates" above. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 584 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 585 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Reject) Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.47 Rejected Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 586 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.74, "Steps for Rejected Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" above. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 587 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Page 588 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Source (Wait) Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed by wait. Figure 8.48 Data Role Swap with Wait, DFP operating as Source initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 589 Table 8.75, "Steps for Data Role Swap with Wait, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" above. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 590 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 591 8.3.2.9.4 Data Role Swap, Initiated by DFP Operating as Sink 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Accept) Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.49 Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) Page 592 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.76, "Steps for Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" above. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 593 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP, still operating as a Sink (Rd asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 594 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Reject) Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.50 Rejected Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 595 Table 8.77, "Steps for Rejected Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" above. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 596 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 597 8.3.2.9.4.3 Data Role Swap, Initiated by DFP Operating as Sink (Wait) Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.51 Data Role Swap with Wait, DFP operating as Sink initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Page 598 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.78, "Steps for Data Role Swap with Wait, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" above. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 599 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 600 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10 VCONN Swap 8.3.2.10.1 VCONN Source Swap, initiated by VCONN Source 8.3.2.10.1.1 VCONN Source Swap, initiated by VCONN Source (Accept) Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source role. Figure 8.52 Successful VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Vconn is on 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Stop SenderResponseTimer Start VCONNOnTimer Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN has been swapped VCONN off VCONN Source Tell power supply to start supplying VCONN VCONN is off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 601 Table 8.79, "Steps for Source to Sink VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" above. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 602 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine asks the DPM to turn on VCONN. 19 The DPM informs the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Source it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 VCONN is off. Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Port Partners have swapped VCONN Source role. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 603 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Reject) Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.53 Rejected VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Page 604 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.80, "Steps for Rejected VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" above. Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 605 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off Page 606 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.1.3 VCONN Source Swap, initiated by VCONN Source (Wait) Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is told to wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.54 VCONN Source Swap with Wait, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 607 Table 8.81, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" above. Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 608 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 609 8.3.2.10.2 VCONN Source Swap, initiated by non-VCONN Source 8.3.2.10.2.1 VCONN Source Swap, initiated by non-VCONN Source (Accept) Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source. Figure 8.55 VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port Vconn is on Start VCONNOnTimer VCONN Source VCONN Off Stop SenderResponseTimer Tell power supply to start supplying VCONN 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Source is supplying VCONN Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN is off Page 610 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.82, "Steps for VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" above. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 611 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNOnTimer. 19 The DPM tells the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Sink it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. VCONN is off. The Port Partners have swapped VCONN Source role. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Page 612 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.2.2 VCONN Source Swap, initiated by non-VCONN Source (Reject) Figure 8.56, "Rejected VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap which is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.56 Rejected VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 613 Table 8.83, "Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.56, "Rejected VCONN Source Swap, initiated by non- VCONN Source" above. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 614 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 615 8.3.2.10.2.3 VCONN Source Swap (Wait) Figure 8.57, "VCONN Source Swap with Wait" shows an example where the Port requests a VCONN Swap which is delayed with a wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.57 VCONN Source Swap with Wait : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Page 616 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.84, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.57, "VCONN Source Swap with Wait" above. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 617 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source Page 618 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11 Additional Capabilities, Status and Information 8.3.2.11.1 Alert 8.3.2.11.1.1 Source sends Alert to a Sink Figure 8.58, "Source Alert to Sink" shows an example sequence between a Source and a Sink where the Source alerts the Sink that there has been a status change. This AMS will be followed by getting the Source status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.58 Source Alert to Sink : Sink Policy Engine : Protocol : PHY : PHY : Protocol : Source Policy Engine Sink Port Source Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 619 Table 8.85, "Steps for Source Alert to Sink" below provides a detailed explanation of what happens at each labeled step in Figure 8.58, "Source Alert to Sink" above. Table 8.85 Steps for Source Alert to Sink Step Sink Source 1 The DPM indicates a Source alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 620 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.1.2 Sink sends Alert to a Source Figure 8.59, "Sink Alert to Source" shows an example sequence between a Source and a Sink where the Sink alerts the Source that there has been a status change. This AMS will be followed by getting the Sink status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.59 Sink Alert to Source : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine Source Port Sink Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 621 Table 8.86, "Steps for Sink Alert to Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.59, "Sink Alert to Source" above. Table 8.86 Steps for Sink Alert to Source Step Source Sink 1 The DPM indicates a Sink alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 622 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2 Status 8.3.2.11.2.1 Sink Gets Source Status Figure 8.60, "Sink Gets Source Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Sink gets more details on the change. Figure 8.60 Sink Gets Source Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 623 Table 8.87, "Steps for a Sink getting Source Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.60, "Sink Gets Source Status" above. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 624 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Source has informed the Sink of its present status. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 625 8.3.2.11.2.2 Source Gets Sink Status Figure 8.61, "Source Gets Sink Status" shows an example sequence between a Source and a Sink where, after the Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Source gets more details on the change. Figure 8.61 Source Gets Sink Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink Status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Page 626 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.88, "Steps for a Source getting Sink Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.61, "Source Gets Sink Status" above. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 627 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Sink has informed the Source of its present status. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port Page 628 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2.3 VCONN Source Gets Cable Plug Status Figure 8.62, "VCONN Source Gets Cable Plug Status" shows an example sequence between a VCONN Source and a Cable Plug where, after the VCONN Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the VCONN Source gets more details on the change. Figure 8.62 VCONN Source Gets Cable Plug Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Status Information from DPM : Policy Engine : Policy Engine VCONN Source Port Cable Plug Stop SenderResponseTimer 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 629 Table 8.89, "Steps for a VCONN Source getting Cable Plug Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.62, "VCONN Source Gets Cable Plug Status" above. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug 1 Policy Engine directs the Protocol Layer to send a Get_Status Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 630 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Cable Plug has informed the VCONN Source of its present status. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 631 8.3.2.11.2.4 Sink Gets Source PPS Status Figure 8.63, "Sink Gets Source PPS Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a PPS status change, the Sink gets more details on the change. Figure 8.63 Sink Gets Source PPS Status : Protocol 1: Send Get_PPS_Status : PHY : PHY : Protocol 2:Get_PPS_Status 3: Get_PPS_Status + CRC 4: Get_PPS_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_PPS_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_PPS_Status sent Start SenderResponseTimer 10: Send PPS_Status 11: PPS_Status 12: PPS_Status + CRC 13: PPS_Status Check MessageID against local copy Store copy of MessageID 14: PPS_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source PPS Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: PPS_Status sent Page 632 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.90, "Steps for a Sink getting Source PPS status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.63, "Sink Gets Source PPS Status" above. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_PPS_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_PPS_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_PPS_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_PPS_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_PPS_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a PPS_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the PPS_Status Message. PHY Layer appends a CRC and sends the PPS_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PPS_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 633 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PPS_Status Message was successfully sent. The Source has informed the Sink of its present PPS status. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port Page 634 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3 Source/Sink Capabilities 8.3.2.11.3.1 SPR 8.3.2.11.3.1.1 Sink Gets Source Capabilities Figure 8.64, "Sink Gets Source's Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source Capabilities. Figure 8.64 Sink Gets Source's Capabilities : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Source_Capabilities sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 635 Table 8.91, "Steps for a Sink getting Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.64, "Sink Gets Source's Capabilities" above. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 636 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its capabilities. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 637 8.3.2.11.3.1.2 Dual-Role Source Gets Source Capabilities from a Dual-Role Sink Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as a Source. Figure 8.65 Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 638 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.92, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" above. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 639 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its capabilities. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 640 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.1.3 Source Gets Sink Capabilities Figure 8.66, "Source Gets Sink's Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink Capabilities. Figure 8.66 Source Gets Sink's Capabilities : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 641 Table 8.93, "Steps for a Source getting Sink Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.66, "Source Gets Sink's Capabilities" above. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 642 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its capabilities. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 643 8.3.2.11.3.1.4 Dual-Role Sink Get Sink Capabilities from a Dual-Role Source Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.67 Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 644 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.94, "Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" above. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 645 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as a Sink. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 646 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2 EPR 8.3.2.11.3.2.1 Sink Gets EPR Source Capabilities Figure 8.68, "Sink Gets Source's EPR Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's EPR Capabilities. Figure 8.68 Sink Gets Source's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 647 Table 8.95, "Steps for a Sink getting EPR Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.68, "Sink Gets Source's EPR Capabilities" above. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present EPR Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 648 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its EPR Capabilities. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 649 8.3.2.11.3.2.2 Dual-Role Source Gets Source Capabilities from a Dual-Role EPR Sink Figure 8.69, "Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as an EPR Source. Figure 8.69 Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 650 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.96, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.69, "Dual-Role Source Gets Dual- Role Sink's Capabilities as an EPR Source" above. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 651 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its EPR Capabilities. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 652 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2.3 Source Gets Sink EPR Capabilities Figure 8.70, "Source Gets Sink's EPR Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's EPR Capabilities. Figure 8.70 Source Gets Sink's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 653 Table 8.97, "Steps for a Source getting Sink EPR Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.70, "Source Gets Sink's EPR Capabilities" above. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 654 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its EPR Capabilities. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 655 8.3.2.11.3.2.4 Dual-Role Sink Get Sink EPR Capabilities from a Dual-Role Source Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.71 Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 656 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.98, "Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" above. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 657 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as an EPR Sink. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 658 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4 Extended Capabilities 8.3.2.11.4.1 Sink Gets Source Extended Capabilities Figure 8.72, "Sink Gets Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Extended Capabilities. Figure 8.72 Sink Gets Source's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 659 Table 8.99, "Steps for a Sink getting Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.72, "Sink Gets Source's Extended Capabilities" above. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 660 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Source has informed the Sink of its Extended Capabilities. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 661 8.3.2.11.4.2 Dual-Role Source Gets Source Capabilities Extended from a Dual- Role Sink Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Source gets the Dual-Role Power Sink's Extended Capabilities as a Source. Figure 8.73 Dual-Role Source Gets Dual-Role Sink's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 662 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.100, "Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" above. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Source which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 663 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its Extended Capabilities as a Source. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 664 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4.3 Source Gets Sink Extended Capabilities Figure 8.74, "Source Gets Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Extended Capabilities. Figure 8.74 Source Gets Sink's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 665 Table 8.101, "Steps for a Source getting Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.74, "Source Gets Sink's Extended Capabilities" above. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 666 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Sink has informed the Source of its Extended Capabilities. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 667 8.3.2.11.4.4 Dual-Role Sink Gets Sink Capabilities Extended from a Dual-Role Source Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Sink gets the Dual-Role Power Source's Extended Capabilities as a Sink. Figure 8.75 Dual-Role Sink Gets Dual-Role Source's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 668 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.102, "Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" above. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Sink which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 669 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Extended Capabilities as a Sink. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 670 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5 Battery Capabilities and Status 8.3.2.11.5.1 Sink Gets Battery Capabilities Figure 8.76, "Sink Gets Source's Battery Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery capabilities for a given Battery. Figure 8.76 Sink Gets Source's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 671 Table 8.103, "Steps for a Sink getting Source Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.76, "Sink Gets Source's Battery Capabilities" above. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 672 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Source has informed the Sink of the Battery capabilities for the requested Battery. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 673 8.3.2.11.5.2 Source Gets Battery Capabilities Figure 8.77, "Source Gets Sink's Battery Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery capabilities for a given Battery. Figure 8.77 Source Gets Sink's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 674 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.104, "Steps for a Source getting Sink Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.77, "Source Gets Sink's Battery Capabilities" above. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 675 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Sink has informed the Source of the Battery capabilities for the requested Battery. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port Page 676 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5.3 Sink Gets Battery Status Figure 8.78, "Sink Gets Source's Battery Status" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery status for a given Battery. Figure 8.78 Sink Gets Source's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 677 Table 8.105, "Steps for a Sink getting Source Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.78, "Sink Gets Source's Battery Status" above. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 678 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Source has informed the Sink of the Battery status for the requested Battery. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 679 8.3.2.11.5.4 Source Gets Battery Status Figure 8.79, "Source Gets Sink's Battery Status" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery status for a given Battery. Figure 8.79 Source Gets Sink's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 680 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.106, "Steps for a Source getting Sink Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.79, "Source Gets Sink's Battery Status" above. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 681 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Sink has informed the Source of the Battery status for the requested Battery. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port Page 682 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6 Manufacturer Information 8.3.2.11.6.1 Source Gets Port Manufacturer Information from a Sink Figure 8.80, "Source Gets Sink's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.80 Source Gets Sink's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 683 Table 8.107, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.80, "Source Gets Sink's Port Manufacturer Information" above. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 684 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 685 8.3.2.11.6.2 Sink Gets Port Manufacturer Information from a Source Figure 8.81, "Sink Gets Source's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.81 Sink Gets Source's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 686 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.108, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.81, "Sink Gets Source's Port Manufacturer Information" above. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 687 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port Page 688 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.3 Source Gets Battery Manufacturer Information from a Sink Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for one of its Batteries. Figure 8.82 Source Gets Sink's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 689 Table 8.109, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" above. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 690 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 691 8.3.2.11.6.4 Sink Gets Battery Manufacturer Information from a Source Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.83 Sink Gets Source's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 692 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.110, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" above. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 693 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port Page 694 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.5 VCONN Source Gets Manufacturer Information from a Cable Plug Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Manufacturer information. Figure 8.84 VCONN Source Gets Cable Plug's Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 695 Table 8.111, "Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" above. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 696 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Cable Plug has informed the Source of its manufacturer information. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 697 8.3.2.11.7 Country Codes 8.3.2.11.7.1 8.3.2.12.7.1Source Gets Country Codes from a Sink Figure 8.85, "Source Gets Sink's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's Country Codes. Figure 8.85 Source Gets Sink's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 698 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.112, "Steps for a Source getting Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.85, "Source Gets Sink's Country Codes" above. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 699 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port Page 700 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.7.2 Sink Gets Country Codes from a Source Figure 8.86, "Sink Gets Source's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.86 Sink Gets Source's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 701 Table 8.113, "Steps for a Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.86, "Sink Gets Source's Country Codes" above. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 702 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 703 8.3.2.11.7.3 VCONN Source Gets Country Codes from a Cable Plug Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Country Codes. Figure 8.87 VCONN Source Gets Cable Plug's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Codes sent Page 704 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.114, "Steps for a VCONN Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" above. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 705 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Cable Plug has informed the Source of its country codes. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug Page 706 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8 Country Information 8.3.2.11.8.1 Source Gets Country Information from a Sink Figure 8.88, "Source Gets Sink's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country information. Figure 8.88 Source Gets Sink's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 707 Table 8.115, "Steps for a Source getting Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.88, "Source Gets Sink's Country Information" above. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific Country Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 708 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 709 8.3.2.11.8.2 Sink Gets Country Information from a Source Figure 8.89, "Sink Gets Source's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.89 Sink Gets Source's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 710 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.116, "Steps for a Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.89, "Sink Gets Source's Country Information" above. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 711 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port Page 712 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8.3 VCONN Source Gets Country Information from a Cable Plug Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's country information. Figure 8.90 VCONN Source Gets Cable Plug's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 713 Table 8.117, "Steps for a VCONN Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" above. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 714 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Cable Plug has informed the Source of its country information. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 715 8.3.2.11.9 Revision Information 8.3.2.11.9.1 Source Gets Revision Information from a Sink Figure 8.91, "Source Gets Sink's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision information. Figure 8.91 Source Gets Sink's Revision Information : Protocol 1: Send Get_Revision : PHY : PHY : Protocol 2:Get_Revision 3: Get_Revision + CRC 4: Get_Revision Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Revision received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Revision sent Start SenderResponseTimer 10: Send Revision 11: Revision 12: Revision + CRC 13: Revision Check MessageID against local copy Store copy of MessageID 14: Revision received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Revision sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 716 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.118, "Steps for a Source getting Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.91, "Source Gets Sink's Revision Information" above. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 717 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port Page 718 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.9.2 Sink Gets Revision Information from a Source Figure 8.92, "Sink Gets Source's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision codes. Figure 8.92 Sink Gets Source's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 719 Table 8.119, "Steps for a Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.92, "Sink Gets Source's Revision Information" above. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 720 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 721 8.3.2.11.9.3 VCONN Source Gets Revision Information from a Cable Plug Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Revision information. Figure 8.93 VCONN Source Gets Cable Plug's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Page 722 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.120, "Steps for a VCONN Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" above. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 723 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Cable Plug has informed the Source of its Revision information. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug Page 724 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.10 Source Information 8.3.2.11.10.1 Sink Gets Source Information Figure 8.94, "Sink Gets Source's Information" shows an example sequence between a Source and a Sink when the Sink gets the Source's information. Figure 8.94 Sink Gets Source's Information : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 725 Table 8.121, "Steps for a Sink getting Source Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.94, "Sink Gets Source's Information" above. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 726 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Source has provided the Sink with its information. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 727 8.3.2.11.10.2 Dual-Role Source Gets Source Information from a Dual-Role Sink Figure 8.95, "Dual-Role Source Gets Dual-Role Sink's Information as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink's Information as a Source. Figure 8.95 Dual-Role Source Gets Dual-Role Sink's Information as a Source : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 728 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.122, "Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.95, "Dual-Role Source Gets Dual- Role Sink's Information as a Source" above. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 729 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Dual-Role Power Sink has provided the Dual-Role Power Source with its information. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 730 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12 Security 8.3.2.12.1 Source requests security exchange with Sink Figure 8.96, "Source requests security exchange with Sink" shows an example sequence for a security exchange between a Source and a Sink. Figure 8.96 Source requests security exchange with Sink : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 731 Table 8.123, "Steps for a Source requesting a security exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.96, "Source requests security exchange with Sink" above. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 732 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 733 8.3.2.12.2 Sink requests security exchange with Source Figure 8.97, "Sink requests security exchange with Source" shows an example sequence for a security exchange between a Sink and a Source. Figure 8.97 Sink requests security exchange with Source : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 734 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.124, "Steps for a Sink requesting a security exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.97, "Sink requests security exchange with Source" above. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 735 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port Page 736 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12.3 VCONN Source requests security exchange with Cable Plug Figure 8.98, "VCONN Source requests security exchange with Cable Plug" shows an example sequence for a security exchange between a VCONN Source and a Cable Plug. Figure 8.98 VCONN Source requests security exchange with Cable Plug : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Vconn Source Cable Plug 18: Security_Response sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 737 Table 8.125, "Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.98, "VCONN Source requests security exchange with Cable Plug" above. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 738 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 739 8.3.2.13 Firmware Update 8.3.2.13.1 Source requests firmware update exchange with Sink Figure 8.99, "Source requests firmware update exchange with Sink" shows an example sequence for a firmware update exchange between a Source and a Sink. Figure 8.99 Source requests firmware update exchange with Sink : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 740 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.126, "Steps for a Source requesting a firmware update exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.99, "Source requests firmware update exchange with Sink" above. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 741 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port Page 742 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.13.2 Sink requests firmware update exchange with Source Figure 8.100, "Sink requests firmware update exchange with Source" shows an example sequence for a firmware update exchange between a Sink and a Source. Figure 8.100 Sink requests firmware update exchange with Source : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 743 Table 8.127, "Steps for a Sink requesting a firmware update exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.100, "Sink requests firmware update exchange with Source" above. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Page 744 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 745 8.3.2.13.3 VCONN Source requests firmware update exchange with Cable Plug Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" shows an example sequence for a firmware update exchange between a VCONN Source and a Cable Plug. Figure 8.101 VCONN Source requests firmware update exchange with Cable Plug : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine VCONN Source Cable Plug 18: Firmware_Update_Response sent Page 746 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.128, "Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" above. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 747 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Page 748 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14 Structured VDM 8.3.2.14.1 Discover Identity 8.3.2.14.1.1 Initiator to Responder Discover Identity (ACK) Figure 8.102, "Initiator to Responder Discover Identity (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers identity information from the Responder. Figure 8.102 Initiator to Responder Discover Identity (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity ACK 11: Discover Identity ACK 12: Discover Identity ACK + CRC 13: Discover Identity ACK Check MessageID against local copy Store copy of MessageID 14: Discover Identity ACK received Stop VDMResponseTimer DPM evaluates Identity information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 749 Table 8.129, "Steps for Initiator to UFP Discover Identity (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.102, "Initiator to Responder Discover Identity (ACK)" above. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command ACK response. 11 Protocol Layer creates the Discover Identity Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 750 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command ACK response was successfully sent. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 751 8.3.2.14.1.2 Initiator to Responder Discover Identity (NAK) Figure 8.103, "Initiator to Responder Discover Identity (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a NAK. Figure 8.103 Initiator to Responder Discover Identity (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity NAK 11: Discover Identity NAK 12: Discover Identity NAK + CRC 13: Discover Identity NAK Check MessageID against local copy Store copy of MessageID 14: Discover Identity NAK received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Page 752 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.130, "Steps for Initiator to UFP Discover Identity (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.103, "Initiator to Responder Discover Identity (NAK)" above. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command NAK response. 11 Protocol Layer creates the Discover Identity Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 753 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder Page 754 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.1.3 Initiator to Responder Discover Identity (BUSY) Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a BUSY. Figure 8.104 Initiator to Responder Discover Identity (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity BUSY 11: Discover Identity BUSY 12: Discover Identity BUSY + CRC 13: Discover Identity BUSY Check MessageID against local copy Store copy of MessageID 14: Discover Identity BUSY received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 755 Table 8.131, "Steps for Initiator to UFP Discover Identity (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" above. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command BUSY response. 11 Protocol Layer creates the Discover Identity Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 756 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 757 8.3.2.14.2 Discover SVIDs 8.3.2.14.2.1 Initiator to Responder Discover SVIDs (ACK) Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers SVID information from the Responder. Figure 8.105 Initiator to Responder Discover SVIDs (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs ACK 11: Discover_SVIDs ACK 12: Discover_SVIDs ACK + CRC 13: Discover_SVIDs ACK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs ACK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 758 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.132, "Steps for DFP to UFP Discover SVIDs (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" above. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command ACK response. 11 Protocol Layer creates the Discover SVIDs Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 759 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command ACK response was successfully sent. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder Page 760 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (NAK) Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a NAK. Figure 8.106 Initiator to Responder Discover SVIDs (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs NAK 11: Discover_SVIDs NAK 12: Discover_SVIDs NAK + CRC 13: Discover_SVIDs NAK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs NAK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 761 Table 8.133, "Steps for DFP to UFP Discover SVIDs (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" above. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command NAK response. 11 Protocol Layer creates the Discover SVIDs Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 762 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command NAK response was successfully sent. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 763 8.3.2.14.2.3 Initiator to Responder Discover SVIDs (BUSY) Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a BUSY. Figure 8.107 Initiator to Responder Discover SVIDs (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs BUSY 11: Discover_SVIDs BUSY 12: Discover_SVIDs BUSY + CRC 13: Discover_SVIDs BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs BUSY received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 764 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.134, "Steps for DFP to UFP Discover SVIDs (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" above. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command BUSY response. 11 Protocol Layer creates the Discover SVIDs Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 765 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command BUSY response was successfully sent. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder Page 766 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3 Discover Modes 8.3.2.14.3.1 Initiator to Responder Discover Modes (ACK) Figure 8.108, "Initiator to Responder Discover Modes (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers Mode information from the Responder. Figure 8.108 Initiator to Responder Discover Modes (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes ACK 11: Discover_Modes ACK 12: Discover_Modes ACK + CRC 13: Discover_Modes ACK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes ACK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 767 Table 8.135, "Steps for DFP to UFP Discover Modes (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.108, "Initiator to Responder Discover Modes (ACK)". Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command ACK response. 11 Protocol Layer creates the Discover Modes Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 768 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command ACK response was successfully sent. Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 769 8.3.2.14.3.2 Initiator to Responder Discover Modes (NAK) Figure 8.109, "Initiator to Responder Discover Modes (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a NAK. Figure 8.109 Initiator to Responder Discover Modes (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes NAK 11: Discover_Modes NAK 12: Discover_Modes NAK + CRC 13: Discover_Modes NAK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes NAK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Page 770 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.136, "Steps for DFP to UFP Discover Modes (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.109, "Initiator to Responder Discover Modes (NAK)". Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 771 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP Page 772 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3.3 Initiator to Responder Discover Modes (BUSY) Figure 8.110, "Initiator to Responder Discover Modes (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a BUSY. Figure 8.110 Initiator to Responder Discover Modes (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes BUSY 11: Discover_Modes BUSY 12: Discover_Modes BUSY + CRC 13: Discover_Modes BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_Modes BUSY received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 773 Table 8.137, "Steps for DFP to UFP Discover Modes (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.110, "Initiator to Responder Discover Modes (BUSY)". Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 774 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 775 8.3.2.14.4 Enter/Exit Mode 8.3.2.14.4.1 DFP to UFP Enter Mode Figure 8.111, "DFP to UFP Enter Mode" shows an example sequence between a DFP and a UFP that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.111 DFP to UFP Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP Supported SVIDS/Modes discovered Enter USB Safe State 37: Send Enter Mode 38: Enter Mode 39: Enter Mode + CRC 40: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 41: Enter Mode received 42: GoodCRC 43: GoodCRC + CRC 44: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 45: Enter Mode sent Start VDMModeEntryTimer 46: Send Enter Mode ACK 47: Enter Mode ACK 48: Enter Mode ACK + CRC 49: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 50: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 51: GoodCRC 52: GoodCRC + CRC 53: GoodCRC 54: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Operation USB Operation Evaluate Enter Mode request Enter New Mode New Mode Entered Page 776 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.138, "Steps for DFP to UFP Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.111, "DFP to UFP Enter Mode" above. Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. The Policy Engine directs the Protocol Layer to send an Enter Mode Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. The Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 777 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and UFP are operating in the new Mode Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP Page 778 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.2 DFP to UFP Exit Mode Figure 8.112, "DFP to UFP Exit Mode" shows an example sequence between a DFP and a UFP, where the DFP commands the UFP to exit the only Active Mode. Figure 8.112 DFP to UFP Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 779 Table 8.139, "Steps for DFP to UFP Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.112, "DFP to UFP Exit Mode" above. Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The UFP is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. The Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 780 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and UFP are in USB Operation Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 781 8.3.2.14.4.3 DFP to Cable Plug Enter Mode Figure 8.113, "DFP to Cable Plug Enter Mode" shows an example sequence between a DFP and a Cable Plug that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.113 DFP to Cable Plug Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug Supported SVIDs/Modes Discovered Enter USB Safe Mode Wait tCableMessage before transmission 19: Send Enter Mode 20: Enter Mode 21: Enter Mode + CRC 22: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Enter Mode received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Enter Mode sent Start VDMModeEntryTimer 10: Send Enter Mode ACK 11: Enter Mode ACK 12: Enter Mode ACK + CRC 13: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 14: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Mode USB Mode Evaluate Enter Mode request Enter New Mode Wait tCableMessage before transmission New Mode Entered Page 782 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.140, "Steps for DFP to Cable Plug Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.113, "DFP to Cable Plug Enter Mode" above. Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. tCableMessage after the last GoodCRC Message was sent the Policy Engine directs the Protocol Layer to send an Enter Mode Command request. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 783 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and Cable Plug are operating in the new Mode Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug Page 784 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.4 DFP to Cable Plug Exit Mode Figure 8.114, "DFP to Cable Plug Exit Mode" shows an example sequence between a USB Type-C® DFP and a Cable Plug, where the DFP commands the Cable Plug to exit an Active Mode. Figure 8.114 DFP to Cable Plug Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation Wait tCableMessage before transmission USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 785 Table 8.141, "Steps for DFP to Cable Plug Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.114, "DFP to Cable Plug Exit Mode" above. Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The Cable Plug is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 786 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and Cable Plug are in USB Operation Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 787 8.3.2.14.4.5 Initiator to Responder Attention Figure 8.115, "Initiator to Responder Attention" shows an example sequence between an Initiator and a Responder, where the Initiator requests attention from the Responder. Figure 8.115 Initiator to Responder Attention : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Responder Initiator 1: Send Attention 2: Attention 3: Attention + CRC 4: Attention Check MessageID against local copy Store copy of MessageID 5: Attention received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Attention sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Page 788 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.142, "Steps for Initiator to Responder Attention" below provides a detailed explanation of what happens at each labeled step in Figure 8.115, "Initiator to Responder Attention" above. Table 8.142 Steps for Initiator to Responder Attention Step Responder Initiator 1 The DPM requests attention. The Policy Engine tells the Protocol Layer to form an Attention Command request. 2 Protocol Layer creates the Attention Command request and passes to PHY Layer. 3 PHY Layer receives the Attention Command request and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Attention Command request. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Attention Command request information to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Attention Command request was successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 789 8.3.2.15 Built in Self-Test (BIST) 8.3.2.15.1 BIST Carrier Mode The following is an example of a BIST Carrier Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.116, "BIST Carrier Mode Test" shows the Messages as they flow across the bus and within the devices. This test enables the measurement of power supply noise and frequency drift. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Carrier Mode BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT starts sending the Test Pattern. 5) Operator does the measurements. 6) The test ends after tBISTContMode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.1, "BIST Carrier Mode". Figure 8.116 BIST Carrier Mode Test : Protocol 1: Send BIST(Carrier Mode) : PHY : PHY : Protocol 2: BIST(Carrier Mode) 3: BIST(Carrier Mode) + CRC 4: BIST(Carrier Mode) Start CRCReceiveTimer 5: BIST(Carrier Mode) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Carrier Mode) sent : Policy Engine : Policy Engine Go to BIST Carrier Mode Tester UUT 12: Send Test Pattern 13: Send Test Pattern 14: Test Pattern Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (after tBISTContMode) Enter BIST Carrier Mode mode 10: Go to BIST Carrier Mode 11: Go to BIST Carrier Mode Page 790 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.143, "Steps for BIST Carrier Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.116, "BIST Carrier Mode Test" above. Table 8.143 Steps for BIST Carrier Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Carrier Mode, to put the UUT into BIST Carrier Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Carrier Mode. The Policy Engine goes to BIST Carrier Mode. 11 Protocol Layer tells PHY Layer to go into BIST Carrier Mode. UUT enters BIST Carrier Mode. 12 The Policy Engine directs the Protocol Layer to start generation of the Test Pattern. 13 Protocol Layer directs the PHY Layer to generate the Test Pattern. 14 PHY Layer receives the Test Pattern stream. PHY Layer generates a continuous Test Pattern stream. The UUT exits BIST Carrier Mode after tBISTContMode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 791 8.3.2.15.2 BIST Test Data Mode The following is an example of a BIST Test Data Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.117, "BIST Test Data Test" shows the Messages as they flow across the bus and within the devices. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Test Data BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) Steps 2and 3 are repeated any number of times. 5) The test ends after Hard Reset Signaling is issued. See also Section 5.9.2, "BIST Test Data Mode" and Section 6.4.3.2, "BIST Test Data Mode". Page 792 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.117 BIST Test Data Test : Protocol 1: Send BIST(Test Data) : PHY : PHY : Protocol 2: BIST(Test Data) 3: BIST(Test Data) + CRC 4: BIST(Test Data) Start CRCReceiveTimer 5: BIST(Test Data) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Test Data) sent : Policy Engine : Policy Engine Go to BIST Test Data mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (Hard Reset) Enter BIST Test Data mode 10: Send BIST(Test Data) 11: BIST(Test Data) 12: BIST(Test Data) + CRC 13: BIST(Test Data) Start CRCReceiveTimer 14: BIST(Test Data) received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: BIST(Test Data) sent Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 793 Table 8.144, "Steps for BIST Test Data Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.117, "BIST Test Data Test" above. Table 8.144 Steps for BIST Test Data Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. UUT enters BIST Test Data Mode. 10 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 13 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. Page 794 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. Repeat steps 10-18 any number of times The UUT exits BIST Test Data Mode after a Hard Reset Table 8.144 Steps for BIST Test Data Test Step Tester UUT Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 795 8.3.2.15.3 BIST Shared Capacity Test Mode The following is an example of a BIST Shared Capacity Test Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.118, "BIST Share Capacity Mode Test" shows the Messages as they flow across the bus and within the devices. This test places the UUT in a compliance test mode where the maximum Source capability is always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Shared Test Mode Entry BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT enters BIST Shared Capacity Test Mode. 5) Operator does the measurements. 6) Tester sends a BIST Message with a BIST Shared Test Mode Exit BIST Data Object. 7) UUT answers with a GoodCRC Message. 8) UUT exits BIST Shared Capacity Test Mode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.3, "BIST Shared Capacity Test Mode". Figure 8.118 BIST Share Capacity Mode Test 12: Send BIST(Shared Capacity Test Mode Exit) 13: BIST(Shared Capacity Test Mode Exit) 14: BIST(Shared Capacity Test Mode Exit) + CRC 15: BIST(Shared Capacity Test Mode Exit) Start CRCReceiveTimer 16: BIST(Shared Capacity Test Mode Exit) received 17: GoodCRC 18: GoodCRC + CRC 19: GoodCRC 20: BIST(Shared Capacity Test Mode) sent Go to BIST Shared Capacity Test Mode Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID EXit BIST Shared Capacity Test Mode mode 21: Exit BIST Shared Capacity Test Mode 22: Exit BIST Shared Capacity Test Mode : Protocol 1: Send BIST(Shared Capacity Test Mode Entry) : PHY : PHY : Protocol 2: BIST(Shared Capacity Test Mode Entry) 3: BIST(Shared Capacity Test Mode Entry) + CRC 4: BIST(Shared Capacity Test Mode Entry) Start CRCReceiveTimer 5: BIST(Shared Capacity Test Mode Entry) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Shared Capacity Test Mode) sent : Policy Engine : Policy Engine Go to BIST Shared Capacity Test Mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Enter BIST Shared Capacity Test Mode mode 10: Go to BIST Shared Capacity Test Mode 11: Go to BIST Shared Capacity Test Mode Tester Performs Tests Page 796 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.145, "Steps for BIST Shared Capacity Test Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.118, "BIST Share Capacity Mode Test" above. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Entry, to put the UUT into BIST Shared Capacity Test Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY LayerPHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Shared Capacity Test Mode. The Policy Engine goes to BIST Shared Capacity Test Mode. 11 Protocol Layer tells PHY Layer to go into BIST Shared Capacity Test Mode. UUT enters BIST Shared Capacity Test Mode. Tester performs tests. 12 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Exit, to take the UUT out of BIST Shared Capacity Test Mode. 13 Protocol Layer creates the Message and passes to PHY Layer. 14 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 15 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 16 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 797 17 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 18 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 19 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 20 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 21 Policy Engine tells Protocol Layer to exit BIST Shared Capacity Test Mode. The Policy Engine exits to BIST Shared Capacity Test Mode. 22 Protocol Layer tells PHY Layer to exit BIST Shared Capacity Test Mode. UUT exits BIST Shared Capacity Test Mode. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT Page 798 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16 Enter USB 8.3.2.16.1 UFP Entering USB4 Mode 8.3.2.16.1.1 UFP Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the UFP. Figure 8.119, "UFP Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.119 UFP Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 799 Table 8.146, "Steps for UFP USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.119, "UFP Entering USB4 Mode (Accept)" above. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 800 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Both Port Partners enter [USB4] operation. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 801 8.3.2.16.1.2 UFP Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the UFP. Figure 8.120, "UFP Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.120 UFP Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 802 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.147, "Steps for UFP USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.120, "UFP Entering USB4 Mode (Reject)" above. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 803 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP Page 804 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.1.3 UFP Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the UFP at this time. Figure 8.121, "UFP Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.121 UFP Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait 14: Wait received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 805 Table 8.148, "Steps for UFP USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.121, "UFP Entering USB4 Mode (Wait)" above. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 806 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 807 8.3.2.16.2 Cable Plug Entering USB4 Mode 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the Cable Plug. Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.122 Cable Plug Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 808 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.149, "Steps for Cable Plug USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" above. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 809 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Cable Plug enters [USB4] operation. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug Page 810 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the Cable Plug. Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.123 Cable Plug Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 811 Table 8.150, "Steps for Cable Plug USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" above. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 812 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 813 8.3.2.16.2.3 Cable Plug Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the Cable Plug at this time. Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.124 Cable Plug Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 814 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.151, "Steps for Cable Plug USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" above. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 815 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug Page 816 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.17 Unstructured Vendor Defined Messages 8.3.2.17.1 Unstructured VDM Figure 8.125, "Unstructured VDM Message Sequence" shows an example sequence of an Unstructured VDM Transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.125 Unstructured VDM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send Unstructured VDM Start CRCReceive Timer 21 : Unstructured VDM 22 : Unstructured VDM + CRC 23 : Unstructured VDM Check MessageID against local copy Store Copy of MessageID 23 : Unstructured VDM Received Evaluate Unstructured VDM Reply with the application specific response which can be again a Unstructured VDM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send Unstructured VDM 11: Unstructured VDM 18: Unstructured VDM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : Unstructured VDM + CRC 16: GoodCRC + CRC 11: Unstructured VDM 15: GoodCRC 14: Unstructured VDM Received Process Unstructured VDM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : Unstructured VDM Sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 817 Table 8.152, "Steps for Unstructured VDM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.125, "Unstructured VDM Message Sequence" above. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send an Unstructured Vendor_Defined Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. PHY Layer receives the Unstructured Vendor_Defined Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Unstructured Vendor_Defined Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form an Unstructured Vendor_Defined Message. 11 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 12 PHY Layer receives the Unstructured Vendor_Defined Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 818 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 819 8.3.2.17.2 VDEM Figure 8.126, "VDEM Message Sequence" shows an example sequence of an VDEM transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.126 VDEM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send VDEM Start CRCReceive Timer 21 : VDEM 22 : VDEM + CRC 23 : VDEM Check MessageID against local copy Store Copy of MessageID 23 : VDEM Received Evaluate VDEM Reply with the application specific response which can be again a VDEM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send VDEM 11: VDEM 18: VDEM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : VDEM + CRC 16: GoodCRC + CRC 11: VDEM 15: GoodCRC 14: VDEM Received Process VDEM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : VDEM Sent Page 820 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.153, "Steps for VDEM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.126, "VDEM Message Sequence" above. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send a Vendor_Defined_Extended Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Vendor_Defined_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Vendor_Defined_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY LayerPHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form a Vendor_Defined_Extended Message. 11 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 12 PHY Layer receives the Vendor_Defined_Extended Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 821 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP Page 822 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3 State Diagrams 8.3.3.1 Introduction to state diagrams used in Chapter 8 The state diagrams defined in Section 8.3.3, "State Diagrams" are Normative and Shall define the operation of the Power Delivery Policy Engine. Note: These state diagrams are not intended to replace a well written and robust design. Figure 8.127 Outline of States Figure 8.127, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state. If there are also "Actions on exit" a list of actions carried out on exiting the state, then these are listed as well; otherwise, this box is omitted from the state. At the bottom the status of PD is listed:  “Power" which indicates the present output power for a Source Port or input power for a Sink Port.  “PD" which indicates the present Attachment status either "Attached", "Detached", or "unknown". Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&". In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams (e.g., Source Port or Sink Port state diagrams). Figure 8.128, "References to states" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the state and whether the state is a DFP or UFP. It has also been necessary to indicate conditional entry to either Source Port or Sink Port state diagrams. This is achieved by the use of a bulleted list indicating the preconditions (see example in Figure 8.129, "Example of state reference with conditions"). It is also possible that the entry and return states are the same. Figure 8.130, "Example of state reference with the same entry and exit" indicates a state reference where each referenced state corresponds to either the entry state or the exit state. <Name of State> Actions on entry: “List of actions to carry out on entering the state” Power (VI) = “Present power level” PD = “attachment status” Actions on exit: “List of actions to carry out on exiting the state” Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 823 Figure 8.128 References to states Figure 8.129 Example of state reference with conditions Figure 8.130 Example of state reference with the same entry and exit Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the particular state it is referenced. As soon as the state is exited then the timer is no longer active. Where the timers continue to run outside of the state (such as the NoResponseTimer), this is called out in the text. Timeouts of the timers are listed as conditions on state transitions. The SenderResponseTimer is a special case, as it May be stopped and started from outside the states in which it is used. To allow this to be done without over-complicating the state diagrams, the SenderResponseTimer is described with its own state diagram (Figure 8.131, "SenderResponseTimer Policy Engine State Diagram"). The control of this Timer is shared between the Policy Engine and the Chunking Layer. <Name of reference state> (<DFP | UFP>) Hard Reset: • Consumer or Consumer/Provider -> PE_SNK_.... • Provider/Consumer in Source role -> PE_SRC_... <Name of reference state 1> or <Name of reference state 2> (<DFP | UFP>) Page 824 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Conditions listed on state transitions will come from one of three sources and, when there is a conflict, Should be serviced in the following order: 1) Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.). 2) Events triggered within the Policy Engine e.g., timer timeouts. 3) Information and requests coming from the Device Policy Manager relating either to Local Policy, or to other modules which the Device Policy Manager controls such as power supply and USB-C® Port Control. Note: The following state diagrams are not intended to cover all possible corner cases that could be encountered. For example, where an outgoing Message is Discarded, due to an incoming Message by the Protocol Layer (see Section 6.12.2.3, "Protocol Layer Message Reception") it will be necessary for the higher layers of the system to handle a retry of the AMS that was being initiated, after first handling the incoming Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 825 8.3.3.1.1 SenderResponseTimer State Diagram Figure 8.131, "SenderResponseTimer Policy Engine State Diagram" below shows the state diagram for the Policy Engine in a Source Port or a Sink Port. The following sections describe operation in each of the states. Figure 8.131 SenderResponseTimer Policy Engine State Diagram 8.3.3.1.1.1 SRT_Stopped State The SRT_Stopped State Shall be the starting state for the SenderResponseTimer either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall stop incrementing the SR_Timer. The Policy Engine Shall transition to the SRT_Running State:  When the SenderResponseTimer is started from within a Policy Engine state, or  When a Start_SRT is requested from the Chunking Layer. 8.3.3.1.1.2 SRT_Running State On entry to the SRT_Running State the SenderResponseTimer state machine Shall:  Set the SR_Timer to zero  Start running SR_Timer. The SenderResponseTimer state machine Shall transition to the SRT_Expired State:  When the SR_Timer reaches its maximum count The SenderResponseTimer state machine Shall transition to the SRT_Stopped State:  When the SenderResponseTimer is stopped by exiting a Policy Engine state, or  When a Stop_SRT is requested from the Chunking Layer SRT_Stopped Actions on entry: Stop Incrementing SR_Timer1 Power-up | Hard Reset | SenderResponseTimer stopped on exit from Policy Engine State | Stop_SRT requested from Chunking Layer Actions on entry: Zero SR_Timer Start Incrementing SR_Timer1 SRT_Running SenderResponseTimer started from within Policy Engine State | Start_SRT requested from Chunking Layer Actions on entry: Inform Policy Engine of SenderResponseTimer timeout SRT_Expired SR_Timer1 reached maximum count Policy Engine informed 1) The SR_Timer is regarded as the mechanism within the SenderResponseTimer state diagram that implements the SenderResponseTimer. Page 826 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.1.1.3 SRT_Expired State On entry to the SRT_Running State the SenderResponseTimer state machine Shall Inform Policy Engine of SenderResponseTimer timeout The Policy Engine Shall then transition to the SRT_Stopped state:  When the Policy Engine has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 827 8.3.3.2 Policy Engine Source Port State Diagram Figure 8.132, "Source Port State Diagram" below shows the state diagram for the Policy Engine in a Source Port. The following sections describe operation in each of the states. Figure 8.132 Source Port State Diagram 1) Implementation of the CapsCounter is Optional. In the case where this is not implemented the Source Shall continue to send Source_Capabilities Messages each time the SourceCapabilityTimer times out. 2) Since the Sink is required to make a Valid request from the offered capabilities the expected transition is via "Request can be met" unless the Source Capabilities have changed since the last offer. 3) “Contract Invalid" means that the previously Negotiated voltage and Current values are no longer included in the Source's new Capabilities. If the Sink fails to make a Valid Request in this case, then Power Delivery operation is no lon- ger possible and Power Delivery mode is exited with a Hard Reset. Protocol LayerReset4 | SwapSourceStartTimer timeout PE_SRC_Discovery Actions on entry: Initialize and run SourceCapabilityTimer Power = Default (5V) or Implicit Contract PD = not Connected PE_SRC_Ready Actions on entry: Notify Protocol Layer of end of AMS8 Initialize and run DiscoverIdentityTimer7 Initialize and run SourcePPSCommTimer10 Initialize and run SourceEPRKeepAliveTimer11 Power = Explicit Contract PD = Connected PE_SRC_Transition_Supply Actions on entry: Send Accept message (within tReceiverResponse) Request Device Policy Manager to transition Power Supply Power = transition PD = Connected Actions on exit: Send PS_RDY message (In SPR Mode & Request Message) | (In EPR Mode & EPR_Request Message) PE_SRC_Negotiate_Capability Actions on entry: Get Device Policy Manager evaluation of sink request: • Can be met • Can’t be met • Could be met later from Power Reserve If the sink request for Operating Current or Operating Power can be met, but the sink still requires more power (“Capability Mismatch”) this information will be passed to Device Policy Manager4 Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SRC_Capability_Response Actions on entry: Send Reject message if request can’t be met Send Wait message if request could be met later from the Power Reserve and present Contract is still valid Power = DefauIt (5V) or Implicit/ Explicit Contract PD = Connected Start Explicit Contract (Reject message sent & Contract still valid) | Wait message sent PE_SRC_Send_Capabilities Actions on entry: Request present source capabilities from Device Policy Manager In SPR Mode Send Source_Capabilities Message In EPR Mode Send EPR_Source_Capabilities Message Increment CapsCounter (optional)1 If GoodCRC received: • stop NoResponseTimer • reset HardResetCounter and CapsCounter • initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SRC_Hard_Reset Actions on entry: Generate Hard Reset signalling Initialize and start NoResponseTimer Start PSHardResetTimer Increment HardResetCounter Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Request can’t be met | Request met later from Power Reserve Explicit Contract & Reject message sent & Contract Invalid4 PSHardResetTimer timeout Request can be met Power supply ready Power source at default (SourceCapabilityTimer timeout & CapsCounter ” nCapsCount1) Capabilities message sending failure (without GoodCRC) ¬ presently PD Connected6 In SPR Mode Request Message received | In EPR Mode EPR_Request Message received PE_SRC_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager12 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Hard reset signalling received SenderResponseTimer timeout not previously PD Connected6& NoResponseTimer timeout & HardResetCounter > nHardResetCount1 PSHardResetTimer timeout (SourceCapabilityTimer timeout & CapsCounter > nCapsCount1) | (not previously PD Connected6 & NoResponseTimer timeout & HardResetCounter > nHardResetCount1) PE_SRC_Startup Actions on entry: Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer (only after Swap) Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SRC_Transition_to_default Actions on entry: Request Device Policy Manager to request power supply Hard Resets to vSafe5V via vSafe0V Reset local HW Request Device Policy Manager to set Port Data Role to DFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected PE_SRC_Disabled Actions on entry: Disable Power Delivery Power = DefauIt (5V) PD =not Connected Actions on exit: Request Device Policy Manager to turn on VCONN Inform Protocol Layer Hard Reset complete ErrorRecovery previously PD Connected6 & NoResponseTimer timeout & HardResetCount > nHardResetCount PE_SRC_Wait_New_Capabilities Actions on entry: Wait for new Source Capabilities9 Power = DefauIt (5V) PD =Connected PE_SRC_Hard_Reset_Received Actions on entry: Start PSHardResetTimer Initialize and start NoResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Source capability change (from Device Policy Manager) no Explicit Contract & (Reject message sent | Wait message sent) Source capability change (from Device Policy Manager) | (In SPR Mode & Get_Source_Cap Message) | (In EPR Mode & EPR_Get_Source_Cap Message) Protocol Error Actions on exit: If the Source is initiating an AMS then notify the Protocol Layer than the first Message in an AMS will follow8 SourcePPSCommTimer timeout | SourceEPRKeepAliveTimer timeout PE_SRC_EPR_Keep_Alive Actions on entry: Send EPR_Keep_Alive_Ack Message Power = Explicit Contract PD = Connected EPR_Keep_Alive Message EPR_Keep_Alive_Ack Sent Hard Reset request from Device Policy Manager | EPR Mode & Request Message received | EPR Capable & SPR Mode & EPR_Request Message received (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities message sent PE_SRC_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Page 828 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) After a Power Swap the New Source is required to wait an additional tSwapSourceStart before sending a Source_Capabilities Message. This delay is not required when first starting up a system. 5) PD Connected is defined as a situation when the Port Partners are actively communicating. The Port Partners remain PD Connected after a Swap until there is a transition to Disabled or the connector is able to identify a Detach. 6) Port Partners are no longer PD Connected after a Hard Reset, but consideration needs to be given as to whether there has been a PD Connection while the Ports have been Attached to prevent unnecessary USB Type-C Error Recovery. 7) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 8) See Section 5.7, "Collision Avoidance", Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". 9) In the PE_SRC_Wait_New_Capabilities State the Device Policy Manager Should either decide to send no further Source Capabilities or Should send a different set of Source Capabilities. Continuing to send the same set of Source Capabilities could result in a live lock situation. 10) The SourcePPSCommTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sourc- es that do not support SPR PPS do not need to implement the SourcePPSCommTimer. 11) The SourceEPRKeepAliveTimer is only initialized and run when the Source is in EPR Mode; Sources that do not support EPR Mode do not need to implement the SourceEPRKeepAliveTimer. 12) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. 8.3.3.2.1 PE_SRC_Startup State PE_SRC_Startup Shall be the starting state for a Source Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the CapsCounter and reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state:  When the Protocol Layer reset has completed if the PE_SRC_Startup state was entered due to the system first starting up.  When the SwapSourceStartTimer times out if the PE_SRC_Startup state was entered as the result of a Power Role Swap. Note: Sources Shall remain in the PE_SRC_Startup state, without sending any Source_Capabilities Messages until a plug is Attached. 8.3.3.2.2 PE_SRC_Discovery State On entry to the PE_SRC_Discovery state the Policy Engine Shall initialize and run the SourceCapabilityTimer in order to trigger sending a Source_Capabilities Message. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The SourceCapabilityTimer times out and CapsCounter ≤ nCapsCount. The Policy Engine May Optionally go to the PE_SRC_Disabled state when:  The Port Partners are not presently PD Connected  And the SourceCapabilityTimer times out  And CapsCounter > nCapsCount. The Policy Engine Shall go to the PE_SRC_Disabled state when:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 829  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. Note: In the PE_SRC_Disabled state the Attached device is assumed to be unresponsive. The Policy Engine operates as if the device is Detached until such time as a Detach/Re-attach is detected. 8.3.3.2.3 PE_SRC_Send_Capabilities State Note: This state can be entered from the PE_SRC_Soft_Reset state. On entry to the PE_SRC_Send_Capabilities state the Policy Engine Shall request the present Port capabilities from the Device Policy Manager. The Policy Engine Shall then request the Protocol Layer to send a capabilities Message containing these capabilities. The Policy Engine Shall request:  A Source_Capabilities Message if the Source is in SPR Mode or  An EPR_Source_Capabilities Message if the Source is in EPR Mode. The Policy Engine Shall then increment the CapsCounter (if implemented). If a GoodCRC Message is received, then the Policy Engine Shall:  Stop the NoResponseTimer.  Reset the HardResetCounter and CapsCounter to zero. Note: The HardResetCounter Shall only be set to zero in this state and at power up; its value Shall be maintained during a Hard Reset.  Initialize and run the SenderResponseTimer. Once a Source_Capabilities Message has been received and acknowledged by a GoodCRC Message, the Sink is required to then send a Request Message within tSenderResponse. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received from the Sink and the Source is operating in SPR Mode or  An EPR_Request Message is received from the Sink and the Source is operating in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Discovery state when:  The Protocol Layer indicates that the Message has not been sent and we are presently not Connected. This is part of the Capabilities sending process whereby successful Message sending indicates connection to a PD Sink Port. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The SenderResponseTimer times out. In this case a transition back to USB Default Operation is required. When:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment)  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. The Policy Engine Shall do one of the following:  Transition to the PE_SRC_Discovery state.  Transition to the PE_SRC_Disabled state. Page 830 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: That in either case the Attached device is assumed to be unresponsive. The Policy Engine Should operate as if the device is Detached until such time as a Detach/Re-attach is detected. The Policy Engine Shall go to the ErrorRecovery state when:  The Port Partners have previously been PD Connected (the Source Port remains Attached to a Port it has had a PD Connection with during this Attachment)  And the NoResponseTimer times out.  And the HardResetCounter > nHardResetCount. 8.3.3.2.4 PE_SRC_Negotiate_Capability State On entry to the PE_SRC_Negotiate_Capability state the Policy Engine Shall ask the Device Policy Manager to evaluate the Request from the Attached Sink. The response from the Device Policy Manager Shall be one of the following:  The Request can be met.  The Request cannot be met  The Request could be met later from the Power Reserve. The Policy Engine Shall transition to the PE_SRC_Transition_Supply state when:  The Request can be met. The Policy Engine Shall transition to the PE_SRC_Capability_Response state when:  The Request cannot be met.  Or the Request can be met later from the Power Reserve. 8.3.3.2.5 PE_SRC_Transition_Supply State The Policy Engine Shall be in the PE_SRC_Transition_Supply state while the power supply is transitioning from one power to another. On entry to the PE_SRC_Transition_Supply state, the Policy Engine Shall request the Protocol Layer to send an Accept Message and inform the Device Policy Manager that it Shall transition the power supply to the Requested power level. Note: If the power supply is currently operating at the requested power no change will be necessary. On exit from the PE_SRC_Transition_Supply state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The Device Policy Manager informs the Policy Engine that the power supply is ready. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.2.6 PE_SRC_Ready State In the PE_SRC_Ready state the PD Source Shall be operating at a stable power with no ongoing Negotiation. It Shall respond to requests from the Sink, events from the Device Policy Manager. On entry to the PE_SRC_Ready state the Source Shall notify the Protocol Layer of the end of the Atomic Message Sequence (AMS). If the transition into PE_SRC_Ready is the result of Protocol Error that has not caused a Soft Reset (see Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram") then the notification to the Protocol Layer of the end of the AMS Shall Not be sent since there is a Message to be processed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 831 On entry to the PE_SRC_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, the Policy Engine Shall:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). On entry to the PE_SRC_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SourcePPSCommTimer. On entry to the PE_SRC_Ready state if the current Explicit Contract is for EPR Mode, then the Policy Engine Shall do the following:  Initialize and run the SourceEPRKeepAliveTimer. On exit from the PE_SRC_Ready, if the Source is initiating an AMS, then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed or  A Get_Source_Cap Message is received, and the Source is in SPR Mode or  An EPR_Get_Source_Cap Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received, and the Source is in SPR Mode or  An EPR_Request Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap state when:  The Device Policy Manager asks for the Sink Capabilities. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Source is operating as an SPR PPS and the SourcePPSCommTimer Timer times-out or  The Source is in EPR Mode and the SourceEPRKeepAliveTimer Timer times-out. The Policy Engine Shall transition to the PE_SRC_EPR_Keep_Alive state when:  An EPR_KeepAlive Message is received. The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap State when:  In EPR Mode and a Get_Source_Cap Message is received or  In SPR Mode and an EPR_Get_Source_Cap Message is received. 8.3.3.2.7 PE_SRC_Disabled State In the PE_SRC_Disabled state the PD Source supplies default power and is unresponsive to USB Power Delivery messaging, but not to Hard Reset Signaling. 8.3.3.2.8 PE_SRC_Capability_Response State The Policy Engine Shall enter the PE_SRC_Capability_Response state if there is a Request received from the Sink that cannot be met based on the present capabilities. When the present Explicit Contract is not within the present capabilities it is regarded as Invalid and a Hard Reset will be triggered. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall request the Protocol Layer to send one of the following: Page 832 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Reject Message - if the request cannot be met or the present Explicit Contract is Invalid.  Wait Message - if the request could be met later from the Power Reserve. A Wait Message Shall Not be sent if the present Explicit Contract is Invalid. The Policy Engine Shall transition to the PE_SRC_Ready state when:  There is an Explicit Contract and  A Reject Message has been sent and the present Explicit Contract is still Valid or  A Wait Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  There is an Explicit Contract and  The Reject Message has been sent and the present Explicit Contract is Invalid (i.e., the Sink had to request a new value so instead we will return to USB Default Operation). The Policy Engine Shall transition to the PE_SRC_Wait_New_Capabilities state when:  There is no Explicit Contract and  A Reject Message has been sent or  A Wait Message has been sent. 8.3.3.2.9 PE_SRC_Hard_Reset State The Policy Engine Shall transition to the PE_SRC_Hard_Reset state from any state when:  Hard Reset request from Device Policy Manager or  In EPR Mode and a Request Message is received or  EPR Capable and in SPR Mode and an EPR_Request Message is received. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall:  request the generation of Hard Reset Signaling by the PHY Layer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out.  initialize and run the PSHardResetTimer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when:  The PSHardResetTimer times out. 8.3.3.2.10 PE_SRC_Hard_Reset_Received State The Policy Engine Shall transition from any state to the PE_SRC_Hard_Reset_Received state when:  Hard Reset Signaling is detected. On entry to the PE_SRC_Hard_Reset_Received state the Policy Engine Shall:  initialize and run the PSHardResetTimer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 833  The PSHardResetTimer times out. 8.3.3.2.11 PE_SRC_Transition_to_default State On entry to the PE_SRC_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the power supply Shall Hard Reset (see Section 7.1.5, "Response to Hard Resets").  request a reset of the local hardware  request the Device Policy Manager to set the Port Data Role to DFP and turn off VCONN. On exit from the PE_SRC_Transition_to_default state the Policy Engine Shall:  request the Device Policy Manager to turn on VCONN  inform the Protocol Layer that the Hard Reset is complete. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Device Policy Manager indicates that the power supply has reached the default level. 8.3.3.2.12 PE_SRC_Get_Sink_Cap State In this state the Policy Engine, due to a request from the Device Policy Manager, Shall request the capabilities from the Attached Sink. On entry to the PE_SRC_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SRC_Ready state when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. 8.3.3.2.13 PE_SRC_Wait_New_Capabilities State In this state the Policy Engine has been unable to Negotiate an Explicit Contract and is waiting for new Capabilities from the Device Policy Manager. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed. 8.3.3.2.14 PE_SRC_EPR_Keep_Alive State On entry to the PE_SRC_EPR_Keep_Alive State the Policy Engine Shall send a EPR_KeepAlive_Ack Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_KeepAlive_Ack Message has been sent. Page 834 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.2.15 8.3.3.2.15PE_SRC_Give_Source_Cap State  On entry to the PE_SRC_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Source Capabilities Message has been successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 835 8.3.3.3 Policy Engine Sink Port State Diagram Figure 8.133, "Sink Port State Diagram" below shows the state diagram for the Policy Engine in a Sink Port. The following sections describe operation in each of the states. Figure 8.133 Sink Port State Diagram 1) Source Capabilities Messages received in States other than PE_SNK_Wait_for_Capabilities, PE_SNK_Ready or PE_SNK_Get_Source_Cap constitute a Protocol Error. 2) The SinkRequestTimer Should Not be stopped if a Ping (Deprecated) Message is received in the PE_SNK_Ready state since it represents the maximum time between requests after a Wait Message which is not reset by a Ping (Deprecat- ed) Message. 3) During a Hard Reset the Source voltage will transition to vSafe0V and then transition to vSafe5V. Sinks need to ensure that VBUS present is not indicated until after the Source has completed the Hard Reset process by detecting both of these transitions. New power required | SinkRequestTimer Timeout | SinkPPSPeriodicTimer Timeout Start Explicit Contract & (Reject message received | Wait message received) Hard reset signalling received Power Sink at default Protocol Layer Reset Hard Reset complete VBUS 6 present3 ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source_Capabilities Message received))1 Device Policy Manager Response received Accept message received PS_RDY message received Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink capabilities message sent ((SinkWaitCapTimer timeout | PSTransitionTimer timeout) & (HardResetCounter ” nHardResetCount)) | Hard Reset request from Device Policy Manager | EPR Mode & (EPR_Source _Capabilites message with An EPR PDO in positions 1..7 | Source_Capabilities Message not requested by Get_Source_caps) PE_SNK_Startup Actions on entry: Reset Protocol Layer Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected SenderResponseTimer Timeout PE_SNK_Discovery Actions on entry: Wait for VBUS 6 Power = Default (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Wait_for_Capabilities Actions on entry: Initialize and run SinkWaitCapTimer Power = Default (5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Evaluate_Capability Actions on entry: Reset HardResetCounter to zero. Ask Device Policy Manager to evaluate the options based on supplied capabilities, any Power Reserve that it needs, and respond indicating the selected capability and, Optionally, a “Capability Mismatch”. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Select_Capability Actions on entry: Send Request based on Device Policy Manager response: • Request from present capabilities • Optionally Indicate that other capabilities would be preferred (“Capability Mismatch”) Initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Transition_Sink Actions on entry: Initialize and run PSTransitionTimer Power = transition PD = Connected Actions on exit: Request Device Policy Manager transitions sink power supply to new power (if required) PE_SNK_Ready Actions on entry: Initialize and run SinkRequestTimer2 (on receiving Wait) Initialize and run DiscoverIdentityTimer4 Initialize and run the SinkPPSPeriodicTimer5 In EPR Mode Initialize and run the SinkEPRKeepAliveTimer8 If Sink supports Fast Role Swap send Get_Sink_Cap Message7 Power = Explicit Contract PD = Connected PE_SNK_Give_Sink_Cap Actions on entry: Get present sink capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected PE_SNK_Hard_Reset Actions on entry: Generate Hard Reset signalling. Increment HardResetCounter. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SNK_Transition_to_default Actions on entry: Request Device Policy Manager to request power sink transition to default Reset local HW Set Port Data Role to UFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected Actions on exit: Inform Protocol Layer Hard Reset complete no Explicit Contract & (Reject message received | Wait message received) ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source Capabilities Message))1 Actions on exit: If the Sink is initiating an AMS then notify the Protocol Layer that the first Message in the AMS will follow. Protocol Error PE_SNK_EPR_Keep_Alive Actions on entry: Send EPR_KeepAlive Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected SinkEPRKeepAliveTimer Timeout EPR_KeepAlive_Ack Message SenderResponseTimer Timeout PE_SNK_Get_Source_Cap Actions on entry: If SPR Mode capabilities requested send Get_Source_Cap Message If EPR Mode capabilities requested send EPR_Get_Source_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get source capabilities request from Device Policy Manager (EPR Mode & SPR Source Capabilities requested & Source_Capabilities Message received) | (SPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message received) | SenderResponseTimer timeout Actions on exit: Pass Source capabilities/outcome to Device Policy Manager (SPR Mode & SPR Source Capabilities requested & Source_Capabilities Message) | (EPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message) Page 836 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 5) The SinkPPSPeriodicTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sinks that do not support PPS do not need to implement the SinkPPSPeriodicTimer. 6) A Sink that is a VPD May use VCONN as a proxy for VBUS. 7) To be sent once, and only required if Fast Role Swap is supported by the Sink. 8.3.3.3.1 PE_SNK_Startup State PE_SNK_Startup Shall be the starting state for a Sink Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). Once the reset process completes, the Policy Engine Shall transition to the PE_SNK_Discovery state. 8.3.3.3.2 PE_SNK_Discovery State In the PE_SNK_Discovery state the Sink Policy Engine waits for VBUS to be present. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Device Policy Manager indicates that VBUS has been detected. 8.3.3.3.3 PE_SNK_Wait_for_Capabilities State On entry to the PE_SNK_Wait_for_Capabilities state the Policy Engine Shall initialize and start the SinkWaitCapTimer. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  The Sink is in SPR Mode and a Source_Capabilities Message is received or  The Sink is in EPR Mode and an EPR_Source_Capabilities Message is received. When the SinkWaitCapTimer times out, the Policy Engine will perform a Hard Reset. 8.3.3.3.4 PE_SNK_Evaluate_Capability State The PE_SNK_Evaluate_Capability state is first entered when the Sink receives its first Source_Capabilities Message from the Source. At this point the Sink knows that it is Attached to and communicating with a PD capable Source. On entry to the PE_SNK_Evaluate_Capability state the Policy Engine Shall request the Device Policy Manager to evaluate the supplied Source Capabilities based on Local Policy. The Device Policy Manager Shall indicate to the Policy Engine the new power level required, selected from the present offered capabilities. The Device Policy Manager Shall also indicate to the Policy Engine a Capabilities Mismatch if the offered power does not meet the device's requirements. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A response is received from the Device Policy Manager. 8.3.3.3.5 PE_SNK_Select_Capability State On entry to the PE_SNK_Select_Capability state the Policy Engine Shall request the Protocol Layer to send a response Message, based on the evaluation from the Device Policy Manager. The Message Shall be one of the following:  A Request from the offered Source Capabilities. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 837  A Request from the offered Source Capabilities with an indication that another power level would be preferred (Capability Mismatch bit set). When in SPR Mode a Request Message Shall be sent. When in EPR Mode an EPR_Request Message Shall be sent. The Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Transition_Sink state when:  An Accept Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  There is no Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Ready state when:  There is an Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs. 8.3.3.3.6 PE_SNK_Transition_Sink State On entry to the PE_SNK_Transition_Sink state the Policy Engine Shall initialize and run the PSTransitionTimer (timeout will lead to a Hard Reset see Section 8.3.3.3.8, "PE_SNK_Hard_Reset State" and Shall then request the Device Policy Manager to transition the Sink's power supply to the new power level. Note: If there is no power level change the Device Policy Manager Should Not affect any change to the power supply. On exit from the PE_SNK_Transition_Sink state the Policy Engine Shall request the Device Policy Manager to transition the Sink's power supply to the new power level. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A PS_RDY Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.3.7 PE_SNK_Ready State In the PE_SNK_Ready state the PD Sink Shall be operating at a stable power level with no ongoing Negotiation. It Shall respond to requests from the Source, events from the Device Policy Manager. On entry to the PE_SNK_Ready state as the result of a wait the Policy Engine Should do the following:  Initialize and run the SinkRequestTimer. On entry to the PE_SNK_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, then the Policy Engine Shall do the following:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). Page 838 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SinkPPSPeriodicTimer. On entry to the PE_SNK_Ready state if the Sink supports Fast Role Swap, then the Policy Engine Shall do the following:  Send a Get_Sink_Cap Message. On exit from the PE_SNK_Ready state, if the transition is as a result of a DPM request to start a new Atomic Message Sequence (AMS) then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  In SPR Mode and a Source_Capabilities Message is received or  In EPR Mode and an EPR_Source_Capabilities Message is received. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A new power level is requested by the Device Policy Manager or  A SinkRequestTimer timeout occurs or  A SinkPPSPeriodicTimer timeout occurs. The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap state when:  Get_Sink_Cap Message is received or  EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap state when:  The Device Policy Manager requests an update of the remote Source Capabilities. The Policy Engine Shall transition to the PE_SNK_EPR_Keep_Alive state when:  The SinkEPRKeepAliveTimer timeouts out. 8.3.3.3.8 PE_SNK_Hard_Reset State The Policy Engine Shall transition to the PE_SNK_Hard_Reset state from any state when:  (PSTransitionTimer times out) and  (HardResetCounter ≤ nHardResetCount)) |  Hard Reset request from Device Policy Manager or  In EPR Mode and  An EPR_Source_Capabilities Message is received with an EPR (A)PDO in object positions 1…7 or  A Source_Capabilities Message is received that has not been requested using a Get_Source_Cap Message. The Policy Engine May transition to the PE_SNK_Hard_Reset state from any state when:  SinkWaitCapTimer times out Note: If the SinkWaitCapTimer times out and the HardResetCounter is greater than nHardResetCount the Sink Shall assume that the Source is non-responsive. Note: The HardResetCounter is reset on a power cycle or Detach. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 839 On entry to the PE_SNK_Hard_Reset state the Policy Engine Shall request the generation of Hard Reset Signaling by the PHY Layer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SNK_Transition_to_default state when:  The Hard Reset is complete. 8.3.3.3.9 PE_SNK_Transition_to_default State The Policy Engine Shall transition from any state to PE_SNK_Transition_to_default state when:  Hard Reset Signaling is detected. When Hard Reset Signaling is received or transmitted then the Policy Engine Shall transition from any state to PE_SNK_Transition_to_default. This state can also be entered from the PE_SNK_Hard_Reset state. On entry to the PE_SNK_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the Sink Shall transition to default  request a reset of the local hardware  request the Device Policy Manager that the Port Data Role is set to UFP. The Policy Engine Shall transition to the PE_SNK_Startup state when:  The Device Policy Manager indicates that the Sink has reached the default level. 8.3.3.3.10 PE_SNK_Give_Sink_Cap State  On entry to the PE_SNK_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Sink_Capabilities Message has been successfully sent. 8.3.3.3.11 PE_SNK_EPR_Keep_Alive On entry to the PE_SNK_EPR_Keep_Alive State the Policy Engine Shall send an EPR_KeepAlive Message and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A EPR_KeepAlive_Ack Message is received. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The SenderResponseTimer times out. 8.3.3.3.12 PE_SNK_Get_Source_Cap State  On entry to the PE_SNK_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. Page 840 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On exit from the PE_SNK_Get_Source_Cap State the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SNK_Ready state when:  In EPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In SPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability State when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 841 8.3.3.4 SOP Soft Reset and Protocol Error State Diagrams 8.3.3.4.1 SOP Source Port Soft Reset and Protocol Error State Diagram Figure 8.134, "SOP Source Port Soft Reset and Protocol Error State Diagram" below shows the state diagram for the Policy Engine in a Source Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.134 SOP Source Port Soft Reset and Protocol Error State Diagram 8.3.3.4.1.1 PE_SRC_Send_Soft_Reset State The PE_SRC_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during a Non-interruptible AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response or  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  The Source is in the PE_SRC_Send_Capabilities state, there is a Source_Capabilities Message sending failure on SOP (without a GoodCRC Message) and the Source is not presently Attached (as indicated in Figure 8.132, "Source Port State Diagram"). In this case, the PE_SRC_Discovery state is entered (see Section 8.3.3.2.2, "PE_SRC_Discovery State").  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.2, "Policy Engine Source Port State Diagram"). In this case Hard Reset Signaling will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case USB Type-C Error Recovery will be triggered directly.  During a Data Role Swap when there is a mismatch in the Port Data Role field (see Section 6.2.1.1.6, "Port Data Role"). In this case USB Type-C Error Recovery will be triggered directly. PE_SRC_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept message Received from SOP Accept message Sent to SOP Soft Reset message Received on SOP PE_SRC_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SRC_Send_Capabilities Transmission Error indication from Protocol Layer PE_SRC_Ready In Explicit Contract & Protocol Error2 before first Message in AMS sent (no GoodCRC received) PE_SRC_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message received on SOP will result in a Not_Supported Message response being generated on SOP (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Source during the EPR Mode entry process. Page 842 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SRC_Ready state where the Message received will be handled as if it had been received in the PE_SRC_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. On entry to the PE_SRC_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message to the Sink on SOP, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.1.2 PE_SRC_Soft_Reset State The PE_SRC_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SRC_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state (see Section 8.3.3.2.3, "PE_SRC_Send_Capabilities State") when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 843 8.3.3.4.2 SOP Sink Port Soft Reset and Protocol Error State Diagram Figure 8.135, "Sink Port Soft Reset and Protocol Error Diagram" below shows the state diagram for the Policy Engine in a Sink Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.135 Sink Port Soft Reset and Protocol Error Diagram 8.3.3.4.2.1 PE_SNK_Send_Soft_Reset State The PE_SNK_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during an AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response.  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). In this case a Hard Reset will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case a Hard Reset will be triggered directly.  During a Data Role Swap when the DFP/UFP Data Roles are changing. In this case USB Type-C Error Recovery will be triggered directly. Note: Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SNK_Ready state where the Message received will be handled as if it had been received in the PE_SNK_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. PE_SNK_Send_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Soft Reset Message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept Message Received on SOP Accept Message Sent to SOP Soft Reset Message Received on SOP PE_SNK_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Accept Message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SNK_Wait_for_Capabilities Transmission Error indication from Protocol Layer PE_SNK_Ready In Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message will result in a Not_Supported Message response being generated (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Sink during the EPR Mode entry process. Page 844 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP to the Source, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.2.2 PE_SNK_Soft_Reset State The PE_SNK_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SNK_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 845 8.3.3.5 Data Reset State Diagrams 8.3.3.5.1 DFP Data_Reset Message State Diagrams Figure 8.136, "DFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a DFP. Figure 8.136 DFP Data_Reset Message State Diagram 8.3.3.5.1.1 PE_DDR_Send_Data_Reset State The PE_DDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_DDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and start the SenderResponseTimer. On exit from the PE_DDR_Send_Data_Reset State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been received and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been received and PE_DDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and start SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_DDR_Wait_for_VCONN_Off Actions on entry: Initialize and start VCONNDischargeTimer Power = Explicit Contract PD = connected Accept Message Received & Not VCONN Source VCONNDischargeTimer Timeout | Protocol Error PS_RDY Received PE_DDR_Perform_Data_Reset Actions on entry: Tell Device Policy Manager to perform Data Reset Power = Explicit Contract PD = connected PE_SRC_Ready or PE_SNK_Ready (DFP) Data Reset process is complete Accept Message Sent & Not VCONN Source Protocol Error DataResetFailTimer Timeout | Protocol Error Actions on exit: Stop DataResetFailTimer Send Data_Reset_Complete Message Actions on exit: Initialize and start DataResetFailTimer1 Actions on exit: Initialize and start DataResetFailTimer1 1) Note that the DataResetFailTimer Shall continue to run in every state until it is stopped or times out. Page 846 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A SenderResponseTimer timeout occurs or  A Protocol Error occurs. 8.3.3.5.1.2 PE_DDR_Data_Reset_Received State The PE_DDR_Data_Reset_Received State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_DDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_DDR_Data_Reset_Received State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been sent and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been sent and  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.1.3 PE_DDR_Wait_For_VCONN_Off State On entry to the PE_DDR_Wait_For_VCONN_Off State the Policy Engine Shall initialize and start the VCONNDischargeTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  A PS_RDY Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The VCONNDischargeTimer has timed out or  A Protocol Error occurs. 8.3.3.5.1.4 PE_DDR_Perform_Data_Reset State On entry to the PE_DDR_Perform_Data_Reset State the Policy Engine Shall request the Device Policy Manager to complete the Data Reset process as defined in Section 6.3.14, "Data_Reset Message". On exit from the PE_DDR_Perform_Data_Reset State the Policy Engine Shall stop the DataResetFailTimer and send a Data_Reset_Complete Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the DFP's Power Role when:  The DPM indicates that Data Reset process is complete (see Section 6.3.14, "Data_Reset Message"). The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailTimer times out  A Protocol Error occurs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 847 8.3.3.5.2 UFP Data_Reset Message State Diagrams Figure 8.137, "UFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a UFP. Figure 8.137 UFP Data_Reset Message State Diagram 8.3.3.5.2.1 PE_UDR_Send_Data_Reset State The PE_UDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_UDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and run the SenderResponseTimer. On exit from the PE_UDR_Send_Data_Reset State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been received and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been received and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when: PE_UDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (UFP) PE_UDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_UDR_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = connected PE_UDR_Send_Ps_Rdy Actions on entry: Send PS_RDY Message Power = Explicit Contract PD = connected VCONN Off1 PE_SRC_Ready or PE_SNK_Ready (UFP) Accept Message Received & Not VCONN Source PS_RDY Message Sent Accept Message Sent & Not VCONN Source Protocol Error PE_UDR_Wait_For_Data_Reset_Complete Actions on entry: Wait for Data_Reset_Complete Message Power = Explicit Contract PD = connected Data_Reset_Complete Message received Protocol Error Protocol Error DataResetFailUFPTimer Timeout2 | Protocol Error Actions on exit: Stop DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 1) VCONN Shall be fully discharged see Section 7.1.15 “Vconn Power Cycle”. 2) Note that the DataResetFailUFPTimer Shall continue to run in every state until it is stopped or times out. Page 848 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The SenderResponseTimer has timed out or  A Protocol Error occurs. 8.3.3.5.2.2 PE_UDR_Data_Reset_Received State The PE_UDR_Data_Reset_Received State Shall be entered from either the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_UDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_UDR_Data_Reset_Received State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been sent and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been sent and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.3 PE_UDR_Turn_Off_VCONN State On entry to the PE_UDR_Turn_Off_VCONN State the Policy Engine Shall request the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition to the PE_UDR_Send_Ps_Rdy State when:  The DPM indicates that VCONN has been turned off (VCONN below vRaReconnect see [USB Type-C 2.4]). The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.4 PE_UDR_Send_Ps_Rdy State On entry to the PE_UDR_Send_Ps_Rdy State the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.5 PE_UDR_Wait_For_Data_Reset_Complete State On entry to the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall wait for the Data_Reset_Complete Message. On exit from the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall stop the DataResetFailUFPTimer. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the UFP's Power Role when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 849  The Data_Reset_Complete Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailUFPTimer times out or  A Protocol Error occurs. Page 850 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6 Not Supported Message State Diagrams 8.3.3.6.1 Source Port Not Supported Message State Diagram Figure 8.138, "Source Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Source Port. Figure 8.138 Source Port Not Supported Message State Diagram 8.3.3.6.1.1 PE_SRC_Send_Not_Supported State The PE_SRC_Send_Not_Supported state Shall be entered from the PE_SRC_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SRC_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SRC_Send_Not_Supported state (from the PE_SRC_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.1.2 PE_SRC_Not_Supported_Received State The PE_SRC_Not_Supported_Received state Shall be entered from the PE_SRC_Ready state when a Not_Supported Message is received. On entry to the PE_SRC_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.1.3 PE_SRC_Chunk_Received State The PE_SRC_Chunk_Received state Shall be entered from the PE_SRC_Ready state as a result of an Unsupported Message being received in the PE_SRC_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). PE_SRC_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SRC_Ready PE_SRC_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SRC_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SRC_Ready state directly (see also Section 8.3.3.4.1 “SOP Source Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 851 On entry to the PE_SRC_Chunk_Received state (from the PE_SRC_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SRC_Send_Not_Supported when:  The ChunkingNotSupportedTimer has timed out. Page 852 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6.2 Sink Port Not Supported Message State Diagram Figure 8.139, "Sink Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Sink Port. Figure 8.139 Sink Port Not Supported Message State Diagram 8.3.3.6.2.1 PE_SNK_Send_Not_Supported State The PE_SNK_Send_Not_Supported state Shall be entered from the PE_SNK_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SNK_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Send_Not_Supported state (from the PE_SNK_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.2.2 PE_SNK_Not_Supported_Received State The PE_SNK_Not_Supported_Received state Shall be entered from the PE_SNK_Ready state when a Not_Supported Message is received. On entry to the PE_SNK_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.2.3 PE_SNK_Chunk_Received State The PE_SNK_Chunk_Received state Shall be entered from the PE_SNK_Ready state as a result of an Unsupported Message being received in the PE_SNK_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Chunk_Received state (from the PE_SNK_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SNK_Send_Not_Supported when: PE_SNK_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SNK_Ready PE_SNK_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SNK_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SNK_Ready state directly (see also Section 8.3.3.4.2 “SOP Sink Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 853  The ChunkingNotSupportedTimer has timed out. Page 854 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7 Alert State Diagrams 8.3.3.7.1 Source Port Source Alert State Diagram Figure 8.140, "Source Port Source Alert State Diagram" shows the state diagram for an Alert Message sent by a Source Port. Figure 8.140 Source Port Source Alert State Diagram 8.3.3.7.1.1 PE_SRC_Send_Source_Alert State The PE_SRC_Send_Source_Alert state Shall be entered from the PE_SRC_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SRC_Send_Source_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SRC_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.1.2 PE_SRC_Wait_for_Get_Status State On entry to the PE_SRC_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The SenderResponseTimer times out. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 855 8.3.3.7.2 Sink Port Source Alert State Diagram Figure 8.141, "Sink Port Source Alert State Diagram" shows the state diagram for an Alert Message received by a Sink Port. Figure 8.141 Sink Port Source Alert State Diagram 8.3.3.7.2.1 PE_SNK_Source_Alert_Received State The PE_SNK_Source_Alert_Received state Shall be entered from the PE_SNK_Ready state when an Alert Message is received. On entry to the PE_SNK_Source_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SNK_Ready State (see Figure 8.133, "Sink Port State Diagram") when:  The DPM does not request status. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Page 856 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7.3 Sink Port Sink Alert State Diagram Figure 8.142, "Sink Port Sink Alert State Diagram" shows the state diagram for an Alert Message sent by a Sink Port. Figure 8.142 Sink Port Sink Alert State Diagram 8.3.3.7.3.1 PE_SNK_Send_Sink_Alert State The PE_SNK_Send_Sink_Alert state Shall be entered from the PE_SNK_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SNK_Send_Sink_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SNK_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.3.2 PE_SNK_Wait_for_Get_Status State On entry to the PE_SNK_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to the PE_SNK_Ready (see Figure 8.133, "Sink Port State Diagram") when:  The SenderResponseTimer times out. PE_SNK_Send_Sink_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Sink alert condition Alert Message sent PE_SNK_Ready SenderResponseTimer Timeout PE_SNK_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 857 8.3.3.7.4 Source Port Sink Alert State Diagram Figure 8.143, "Source Port Sink Alert State Diagram" shows the state diagram for an Alert Message received by a Source Port. Figure 8.143 Source Port Sink Alert State Diagram 8.3.3.7.4.1 PE_SRC_Sink_Alert_Received State The PE_SRC_Sink_Alert_Received state Shall be entered from the PE_SRC_Ready state when an Alert Message is received. On entry to the PE_SRC_Sink_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The DPM does not request status. PE_SRC_Sink_Alert_Received Actions on entry: Inform DPM of the detail of the alert Power = Explicit Contract PD = connected Sink Alert Message received DPM does not request status PE_SRC_Ready PE_Get_Status DPM Requests Status Page 858 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8 Source/Sink Capabilities Extended State Diagrams 8.3.3.8.1 Sink Port Get Source Capabilities Extended State Diagram Figure 8.144, "Sink Port Get Source Capabilities Extended State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.144 Sink Port Get Source Capabilities Extended State Diagram 8.3.3.8.1.1 PE_SNK_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 859 8.3.3.8.2 Source Give Source Capabilities Extended State Diagram Figure 8.145, "Source Give Source Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.145 Source Give Source Capabilities Extended State Diagram 8.3.3.8.2.1 PE_SRC_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_SRC_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SRC_Ready PE_SRC_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 860 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8.3 Source Port Get Sink Capabilities Extended State Diagram Figure 8.146, "Source Port Get Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.146 Source Port Get Sink Capabilities Extended State Diagram 8.3.3.8.3.1 PE_SRC_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Sink_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_SRC_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass sink extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 861 8.3.3.8.4 Sink Give Sink Capabilities Extended State Diagram Figure 8.147, "Sink Give Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.147 Sink Give Sink Capabilities Extended State Diagram 8.3.3.8.4.1 PE_SNK_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_SNK_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Sink_Capabilities_Extended Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SNK_Ready PE_SNK_Give_Sink_Cap_Ext Actions on entry: Get present extended Sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 862 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.9 Source Information State Diagrams 8.3.3.9.1 Sink Port Get Source Information State Diagram Figure 8.148, "Sink Port Get Source Information State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.148 Sink Port Get Source Information State Diagram 8.3.3.9.1.1 PE_SNK_Get_Source_Info State The Policy Engine Shall transition to the PE_SNK_Get_Source_Info state, from the PE_SNK_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Info Message is received  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 863 8.3.3.9.2 Source Give Source Information State Diagram Figure 8.149, "Source Give Source Information State Diagram" shows the state diagram for a Source on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.149 Source Give Source Information State Diagram 8.3.3.9.2.1 PE_SRC_Give_Source_Info State The Policy Engine Shall transition to the PE_SRC_Give_Source_Info state, from the PE_SRC_Ready state, when a Get_Source_Info Message is received. On entry to the PE_SRC_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SRC_Ready PE_SRC_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 864 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10 Status State Diagrams 8.3.3.10.1 Get Status State Diagram Figure 8.150, "Get Status State Diagram" shows the state diagram for a Port on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Status. See also Section 6.5.2, "Status Message". Figure 8.150 Get Status State Diagram 8.3.3.10.1.1 PE_Get_Status State The Policy Engine Shall transition to the PE_Get_Status state, from the PE_SRC_Ready or PE_SNK_Ready States, due to a request to get the Port Partner or Cable Plug's status from the Device Policy Manager. On entry to the PE_Get_Status state the Policy Engine Shall send a Get_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram" or Figure 8.133, "Sink Port State Diagram") when:  A Status Message is received  Or SenderResponseTimer times out. get status request from Device Policy Manager Status Message received | SenderResponseTimer Timeout PE_SNK_Ready, PE_SRC_Ready PE_Get_Status Actions on entry: Send Get_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 865 8.3.3.10.2 Give Status State Diagram Figure 8.151, "Give Status State Diagram" shows the state diagram for a Source on receiving a Get_Status Message. See also Section 6.5.2, "Status Message". Figure 8.151 Give Status State Diagram 8.3.3.10.2.1 PE_Give_Status State The Policy Engine Shall transition to the PE_Give_Status state, from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States, when a Get_Status Message is received. On entry to the PE_Give_Status state the Policy Engine Shall request the present Source status from the Device Policy Manager and then send a Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram"and Figure 8.203, "Cable Ready State Diagram") when:  The Status Message has been successfully sent. Get_Status Message received Status Message sent PE_SRC_Ready, PE_SNK_Ready, PE_CBL_Ready PE_Give_Status Actions on entry: Get present Status from Device Policy Manager Send Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 866 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10.3 Sink Port Get Source PPS Status State Diagram Figure 8.152, "Sink Port Get Source PPS Status State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source status when operating as a PPS. See also Section 6.5.10, "PPS_Status Message". Figure 8.152 Sink Port Get Source PPS Status State Diagram 8.3.3.10.3.1 PE_SNK_Get_PPS_Status State The Policy Engine Shall transition to the PE_SNK_Get_PPS_Status state, from the PE_SNK_Ready state, due to a request to get the remote Source PPS status from the Device Policy Manager. On entry to the PE_SNK_Get_PPS_Status state the Policy Engine Shall send a Get_PPS_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_PPS_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A PPS_Status Message is received  Or SenderResponseTimer times out. get PPS status request from Device Policy Manager PPS_Status Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_PPS_Status Actions on entry: Send Get_PPS_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 867 8.3.3.10.4 Source Give Source PPS Status State Diagram Figure 8.153, "Source Give Source PPS Status State Diagram" shows the state diagram for a Source on receiving a Get_PPS_Status Message. See also Section 6.5.10, "PPS_Status Message". Figure 8.153 Source Give Source PPS Status State Diagram 8.3.3.10.4.1 PE_SRC_Give_PPS_Status State The Policy Engine Shall transition to the PE_SRC_Give_PPS_Status state, from the PE_SRC_Ready state, when a Get_PPS_Status Message is received. On entry to the PE_SRC_Give_PPS_Status state the Policy Engine Shall request the present Source PPS status from the Device Policy Manager and then send a PPS_Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The PPS_Status Message has been successfully sent. Get_PPS_Status Message received PPS_Status Message sent PE_SRC_Ready PE_SRC_Give_PPS_Status Actions on entry: Get present Source PPS status from Device Policy Manager Send PPS_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 868 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.11 Battery Capabilities State Diagrams 8.3.3.11.1 Get Battery Capabilities State Diagram Figure 8.154, "Get Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery capabilities for a specified Battery. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.154 Get Battery Capabilities State Diagram 8.3.3.11.1.1 PE_Get_Battery_Cap State The Policy Engine Shall transition to the PE_Get_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery capabilities, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Cap state the Policy Engine Shall send a Get_Battery_Cap Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Capabilities Message is received  Or SenderResponseTimer times out. get Battery capabilities request from Device Policy Manager Battery_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Cap Actions on entry: Send Get_Battery_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 869 8.3.3.11.2 Give Battery Capabilities State Diagram Figure 8.155, "Give Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Cap Message. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.155 Give Battery Capabilities State Diagram 8.3.3.11.2.1 PE_Give_Battery_Cap State The Policy Engine Shall transition to the PE_Give_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Cap Message is received. On entry to the PE_Give_Battery_Cap state the Policy Engine Shall request the present Battery capabilities, for the requested Battery, from the Device Policy Manager and then send a Battery_Capabilities Message based on these capabilities. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Capabilities Message has been successfully sent. Get_Battery_Cap Message received Battery_Capabilities Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Cap Actions on entry: Get present Battery capabilities from Device Policy Manager Send Battery_Capabilities Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 870 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.12 Battery Status State Diagrams 8.3.3.12.1 Get Battery Status State Diagram Figure 8.156, "Get Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery status for a specified Battery. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.156 Get Battery Status State Diagram 8.3.3.12.1.1 PE_Get_Battery_Status State The Policy Engine Shall transition to the PE_Get_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery status, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Status state the Policy Engine Shall send a Get_Battery_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Status Message is received  Or SenderResponseTimer times out. get Battery status request from Device Policy Manager Battery_Status Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Status Actions on entry: Send Get_Battery_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 871 8.3.3.12.2 Give Battery Status State Diagram Figure 8.157, "Give Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Status Message. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.157 Give Battery Status State Diagram 8.3.3.12.2.1 PE_Give_Battery_Status State The Policy Engine Shall transition to the PE_Give_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Status Message is received. On entry to the PE_Give_Battery_Status state the Policy Engine Shall request the present Battery status, for the requested Battery, from the Device Policy Manager and then send a Battery_Status Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Status Message has been successfully sent. Get_Battery_Status Message received Battery_Status Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Status Actions on entry: Get present Battery status from Device Policy Manager Send Battery_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 872 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.13 Manufacturer Information State Diagrams 8.3.3.13.1 Get Manufacturer Information State Diagram Figure 8.158, "Get Manufacturer Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Manufacturer Information. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.158 Get Manufacturer Information State Diagram 8.3.3.13.1.1 PE_Get_Manufacturer_Info State The Policy Engine Shall transition to the PE_Get_Manufacturer_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Manufacturer_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Manufacturer_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Manufacturer_Info Message is received  Or SenderResponseTimer times out. get manufacturer information request from Device Policy Manager Manufacturer_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Manfacturer_Info Actions on entry: Send Get_Manfacturer_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Manufacturer Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 873 8.3.3.13.2 Give Manufacturer Information State Diagram Figure 8.159, "Give Manufacturer Information State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Manufacturer_Info Message. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.159 Give Manufacturer Information State Diagram 8.3.3.13.2.1 PE_Give_Manufacturer_Info State The Policy Engine Shall transition to the PE_Give_Manufacturer_Info state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Manufacturer_Info Message is received. On entry to the PE_Give_Manufacturer_Info state the Policy Engine Shall request the manufacturer information from the Device Policy Manager and then send a Manufacturer_Info Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Manufacturer_Info Message has been successfully sent. Get_Manufacturer_Info Message received Manufacturer_Info Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Manufacturer_Info Actions on entry: Get present Manufacturer Information from Device Policy Manager Send Manufacturer_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 874 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14 Country Codes and Information State Diagrams 8.3.3.14.1 Get Country Codes State Diagram Figure 8.160, "Get Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Codes. See also Section 6.5.11, "Country_Codes Message". Figure 8.160 Get Country Codes State Diagram 8.3.3.14.1.1 PE_Get_Country_Codes State The Policy Engine Shall transition to the PE_Get_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Country Codes from the Device Policy Manager. On entry to the PE_Get_Country_Codes state the Policy Engine Shall send a Get_Country_Codes Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Codes state the Policy Engine Shall inform the Device Policy Manager of the outcome (Country Codes or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Codes Message is received  Or SenderResponseTimer times out. get country codes request from Device Policy Manager Country_Codes Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Codes Actions on entry: Send Get_Country_Codes Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Codes/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 875 8.3.3.14.2 Give Country Codes State Diagram Figure 8.161, "Give Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Codes Message. See also Section 6.5.11, "Country_Codes Message". Figure 8.161 Give Country Codes State Diagram 8.3.3.14.2.1 PE_Give_Country_Codes State The Policy Engine Shall transition to the PE_Give_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Codes Message is received. On entry to the PE_Give_Country_Codes state the Policy Engine Shall request the country codes from the Device Policy Manager and then send a Country_Codes Message containing these codes. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Codes Message has been successfully sent. Get_Country_Codes Message received Country_Codes Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Codes Actions on entry: Get present Country Codes from Device Policy Manager Send Country_Codes Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 876 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14.3 Get Country Information State Diagram Figure 8.162, "Get Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Information. See also Section 6.5.12, "Country_Info Message". Figure 8.162 Get Country Information State Diagram 8.3.3.14.3.1 PE_Get_Country_Info State The Policy Engine Shall transition to the PE_Get_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Country_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (country information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Info Message is received  Or SenderResponseTimer times out. get country information request from Device Policy Manager Country_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Info Actions on entry: Send Get_Country_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 877 8.3.3.14.4 Give Country Information State Diagram Figure 8.163, "Give Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Info Message. See also Section 6.5.12, "Country_Info Message". Figure 8.163 Give Country Information State Diagram 8.3.3.14.4.1 PE_Give_Country_Info State The Policy Engine Shall transition to the PE_Give_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Info Message is received. On entry to the PE_Give_Country_Info state the Policy Engine Shall request the country information from the Device Policy Manager and then send a Country_Info Message containing this country information. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Info Message has been successfully sent. Get_Country_Info Message received Country_Info Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Info Actions on entry: Get present Country Information from Device Policy Manager Send Country_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 878 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.15 Revision State Diagrams 8.3.3.15.1 Get Revision State Diagram Figure 8.164, "Get Revision State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Revision Information. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.164 Get Revision State Diagram 8.3.3.15.1.1 PE_Get_Revision State The Policy Engine Shall transition to the PE_Get_Revision state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Revision Information from the Device Policy Manager. On entry to the PE_Get_Revision state the Policy Engine Shall send a Get_Revision Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Revision state the Policy Engine Shall inform the Device Policy Manager of the outcome (Revision information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Revision Message is received  Or SenderResponseTimer times out. get Revision request from Device Policy Manager Revision Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Revision Actions on entry: Send Get_Revision Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Revision Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 879 8.3.3.15.2 Give Revision State Diagram Figure 8.165, "Give Revision State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Revision Message. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.165 Give Revision State Diagram 8.3.3.15.2.1 PE_Give_Revision State The Policy Engine Shall transition to the PE_Give_Revision state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Revision Message is received. On entry to the PE_Give_Revision state the Policy Engine Shall request the Revision information from the Device Policy Manager and then send a Revision Message based on this information. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Revision Message has been successfully sent. Get_Revision Message received Revision Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Revision Actions on entry: Get present Revision Information from Device Policy Manager Send Revision Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 880 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.16 Enter_USB Message State Diagrams 8.3.3.16.1 DFP Enter_USB Message State Diagrams Figure 8.166, "DFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message sent by a DFP. Figure 8.166 DFP Enter_USB Message State Diagram 8.3.3.16.1.1 PE_DEU_Send_Enter_USB State The PE_DEU_Send_Enter_USB State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager and the Port is operating as a DFP. On entry to the PE_DEU_Send_Enter_USB State the Policy Engine Shall request the Protocol Layer to send an Enter_USB Message and then initialize and run the SenderResponseTimer. On exit from the PE_DEU_Send_Enter_USB state the Policy Engine Shall inform the Device Policy Manager of the outcome: Accept Message received, Reject Message received, SenderResponseTimer timeout. The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready State depending on the Ports Power Role when:  An Accept Message has been received or  A Wait Message has been received or  A Reject Message has been received  There is a SenderResponseTimer timeout. PE_DEU_Send_Enter_USB Actions on entry: Send Enter_USB Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Enter USB (USB Mode) request from DPM Accept Message Received | Reject Message Received | Wait Message Received | SenderResponseTimer timeout PE_SRC_Ready or PE_SNK_Ready (DFP) Actions on exit: Inform Device Policy Manager of Accept, Wait, Reject or timeout. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 881 8.3.3.16.2 UFP or Cable Plug Enter_USB Message State Diagrams Figure 8.167, "UFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message received by a UFP or Cable Plug. Figure 8.167 UFP Enter_USB Message State Diagram 8.3.3.16.2.1 PE_UEU_Enter_USB_Received State The PE_UEU_Enter_USB_Received state Shall be entered from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when an Enter_USB Message is received and the Port is operating as a UFP or is a Cable Plug. On entry to the PE_UEU_Enter_USB_Received state the Policy Engine Shall inform the Device Policy Manager. The Device Policy Manager responds with an indication of whether the Enter_USB Message is to be accepted or rejected. The Policy Engine Shall send either an Accept Message, a Wait Message or a Reject Message as appropriate. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate when:  Either an Accept Message, a Wait Message or a Reject Message has been sent. PE_SRC_Ready (UFP), PE_SNK_Ready (UFP) or PE_CBL_Ready PE_UEU_Enter_USB_Received Actions on entry: Inform Device Policy Manager of Enter_USB Message Send Accept/Wait/Reject Message based on DPM response Power = Explicit Contract PD = connected Enter_USB Message Received Accept/Wait/Reject Message sent Page 882 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17 Security State Diagrams 8.3.3.17.1 Send Security Request State Diagram Figure 8.168, "Send security request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a security request. See also Section 6.5.8, "Security Messages". Figure 8.168 Send security request State Diagram 8.3.3.17.1.1 PE_Send_Security_Request State The Policy Engine Shall transition to the PE_Send_Security_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a security request from the Device Policy Manager. On entry to the PE_Send_Security_Request state the Policy Engine Shall send a Security_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Security_Request Message has been sent. Send security request from Device Policy Manager Security_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Security_Request Actions on entry: Send Security_Request Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 883 8.3.3.17.2 Send Security Response State Diagram Figure 8.169, "Send security response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Security_Request Message. See also Section 6.5.8, "Security Messages". Figure 8.169 Send security response State Diagram 8.3.3.17.2.1 PE_Send_Security_Response State The Policy Engine Shall transition to the PE_Send_Security_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Security_Request Message is received. On entry to the PE_Send_Security_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Security_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Security_Response Message has been successfully sent. Security_Request Message received Security_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Security_Response Actions on entry: Get present Security response from Device Policy Manager Send Security_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 884 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17.3 Security Response Received State Diagram Figure 8.170, "Security response received State Diagram" shows the state diagram for a Source or Sink on receiving a Security_Response Message. See also Section 6.5.8, "Security Messages". Figure 8.170 Security response received State Diagram 8.3.3.17.3.1 PE_Security_Response_Received State The Policy Engine Shall transition to the PE_Security_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Security_Response Message is received. On entry to the PE_Security_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the security response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Security_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Security_Response_Received Actions on entry: Inform Device Policy Manager of the security response details. Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 885 8.3.3.18 Firmware Update State Diagrams 8.3.3.18.1 Send Firmware Update Request State Diagram Figure 8.171, "Send firmware update request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a firmware update request. See also Section 6.5.9, "Firmware Update Messages". Figure 8.171 Send firmware update request State Diagram 8.3.3.18.1.1 PE_Send_Firmware_Update_Request State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a firmware update request from the Device Policy Manager. On entry to the PE_Send_Firmware_Update_Request state the Policy Engine Shall send a Firmware_Update_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Firmware_Update_Request Message has been sent. Send firmware update request from Device Policy Manager Firmware_Update_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Firmware_Update_Request Actions on entry: Send Firmware_Update_Request Message Power = Explicit Contract PD = Connected Page 886 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.18.2 Send Firmware Update Response State Diagram Figure 8.172, "Send firmware update response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Firmware_Update_Request Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.172 Send firmware update response State Diagram 8.3.3.18.2.1 PE_Send_Firmware_Update_Response State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Firmware_Update_Request Message is received. On entry to the PE_Send_Firmware_Update_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Firmware_Update_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Firmware_Update_Response Message has been successfully sent. Firmware_Update_Request Message received Firmware_Update_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Firmware_Update_Response Actions on entry: Get present firmware update response from Device Policy Manager Send Firmware_Update_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 887 8.3.3.18.3 Firmware Update Response Received State Diagram Figure 8.173, "Firmware update response received State Diagram" shows the state diagram for a Source or Sink on receiving a Firmware_Update_Response Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.173 Firmware update response received State Diagram 8.3.3.18.3.1 PE_Firmware_Update_Response_Received State The Policy Engine Shall transition to the PE_Firmware_Update_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Firmware_Update_Response Message is received. On entry to the PE_Firmware_Update_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the firmware update response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Firmware_Update_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Firmware_Update_Response_Received Actions on entry: Inform Device Policy Manager of the firmware update response details. Power = Explicit Contract PD = Connected Page 888 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19 Dual-Role Port State Diagrams Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition they Shall have the capability to perform a Power Role Swap from the PE_SRC_Ready or PE_SNK_Ready states and Shall return to USB Default Operation on a Hard Reset. The State Diagrams in this section Shall apply to every [USB Type-C 2.4] DRP. 8.3.3.19.1 DFP to UFP Data Role Swap State Diagram Figure 8.174, "DFP to UFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DFP to UFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.174 DFP to UFP Data Role Swap State Diagram 8.3.3.19.1.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Evaluate_Swap state when:  A DR_Swap Message is received and PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DRS_DFP_UFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_DFP_UFP_ Change_to_UFP Actions on entry: Request Device Policy Manager to change port to UFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_DFP_UFP_ Send_Swap Actions on entry: Send Swap DR message Initialize and run SenderResponseTimer Reject message received | Wait message received | SenderResponseTimer timeout PE_DRS_DFP_UFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_DFP_UFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept message sent Port changed to UFP PE_SRC_Ready or PE_SNK_Ready (UFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap message received & in Modal Operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 889  There are no Active Modes (not in Modal Operation). The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.1.2 PE_DRS_DFP_UFP_Evaluate_Swap State On entry to the PE_DRS_DFP_UFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.1.3 PE_DRS_DFP_UFP_Accept_Swap State On entry to the PE_DRS_DFP_UFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  The Accept Message has been sent. 8.3.3.19.1.4 PE_DRS_DFP_UFP_Change_to_UFP State On entry to the PE_DRS_DFP_UFP_Change_to_UFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a DFP to a UFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a UFP. 8.3.3.19.1.5 PE_DRS_DFP_UFP_Send_Swap State On entry to the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  An Accept Message is received. 8.3.3.19.1.6 PE_DRS_DFP_UFP_Reject_Swap State On entry to the PE_DRS_DFP_UFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send: Page 890 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Reject Message if the device is unable to perform a Data Role Swap at this time.  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 891 8.3.3.19.2 UFP to DFP Data Role Swap State Diagram Figure 8.175, "UFP to DFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DRP UFP to DFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.175 UFP to DFP Data Role Swap State Diagram 8.3.3.19.2.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from the either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Evaluate_Swap state when:  A DR_Swap Message is received and  There are no Active Modes (not in Modal Operation). PE_SRC_Ready or PE_SNK_Ready (UFP) PE_DRS_UFP_DFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_UFP_DFP_ Change_to_DFP Actions on entry: Request Device Policy Manager to change port to DFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_UFP_DFP_ Send_Swap Actions on entry: Send Swap DR Message Initialize and run SenderResponseTimer Reject Message received | Wait Message received | SenderResponseTimer timeout PE_DRS_UFP_DFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_UFP_DFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap Message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept Message sent Port changed to DFP PE_SRC_Ready or PE_SNK_Ready (DFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap Message received & in Modal Operation Page 892 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.2.2 PE_DRS_UFP_DFP_Evaluate_Swap State On entry to the PE_DRS_UFP_DFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.2.3 PE_DRS_UFP_DFP_Accept_Swap State On entry to the PE_DRS_UFP_DFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  The Accept Message has been sent. 8.3.3.19.2.4 PE_DRS_UFP_DFP_Change_to_DFP State On entry to the PE_DRS_UFP_DFP_Change_to_DFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a UFP to a DFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a DFP. 8.3.3.19.2.5 PE_DRS_UFP_DFP_Send_Swap State On entry to the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a UFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  An Accept Message is received. 8.3.3.19.2.6 PE_DRS_UFP_DFP_Reject_Swap State On entry to the PE_DRS_UFP_DFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Data Role Swap at this time. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 893  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a UFP and Shall transition to the either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Page 894 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.3 Policy Engine in Source to Sink Power Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.176, "Dual-Role Port in Source to Sink Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Figure 8.176 Dual-Role Port in Source to Sink Power Role Swap State Diagram PE_SRC_Ready PE_PRS_SRC_SNK_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SRC_SNK_ Transition_to_off Actions on entry: Tell Device Policy Manager to turn off power supply Power = Transition to stop sourcing PD = Connected PE_PRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Source off PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SRC_SNK_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected Accept received PE_PRS_SRC_SNK_ Reject_PR_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PS_RDY Message received PE_SNK_Startup PE_PRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Source off PD = Connected Source turned off Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 895 8.3.3.19.3.1 PE_SRC_Ready State The Power Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Evaluate_Swap state when:  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.3.2 PE_PRS_SRC_SNK_Evaluate_Swap State On entry to the PE_PRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK.  Or further evaluation of the Power Role Swap request is needed. 8.3.3.19.3.3 PE_PRS_SRC_SNK_Accept_Swap State On entry to the PE_PRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.3.4 PE_PRS_SRC_SNK_Transition_to_off State On entry to the PE_PRS_SRC_SNK_Transition_to_off state the Policy Engine Shall request the Device Policy Manager to turn off the Source. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that the Source has been turned off. 8.3.3.19.3.5 PE_PRS_SRC_SNK_Assert_Rd State On entry to the PE_PRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.3.6 PE_PRS_SRC_SNK_Wait_Source_on State On entry to the PE_PRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the remote Source is now supplying power. The Policy Engine Shall transition to the ErrorRecovery state when: Page 896 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.3.7 PE_PRS_SRC_SNK_Send_Swap State On entry to the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.3.8 PE_PRS_SRC_SNK_Reject_Swap State On entry to the PE_PRS_SRC_SNK_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SRC_Ready when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 897 8.3.3.19.4 Policy Engine in Sink to Source Power Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.177, "Dual-role Port in Sink to Source Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 898 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.177 Dual-role Port in Sink to Source Power Role Swap State Diagram 8.3.3.19.4.1 PE_SNK_Ready State The Power Role Swap process Shall start only from the PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Evaluate_Swap state when: PE_SNK_Ready PE_PRS_SNK_SRC_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Tell Device Policy Manager to turn off Power Sink. Power = Transition to stop sinking PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SNK_SRC_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SNK_SRC_Accept_Swap Actions on entry: Send Accept Message Disable Fast Role Swap Receiver if enabled Power = Explicit Contract PD = Connected Accept Message received PE_PRS_SNK_SRC_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PE_PRS_SNK_SRC_ Source_on Actions on entry: Tell Device Policy Manager to turn on Source Power = Transition to source on PD = Connected VBUS is at vSafe5V Actions on exit: Send PS_RDY Message PE_SRC_Startup Message sent PE_PRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Source off PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 899  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.4.2 PE_PRS_SNK_SRC_Evaluate_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK. 8.3.3.19.4.3 PE_PRS_SNK_SRC_Accept_Swap State On entry to the PE_PRS_SNK_SRC_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message and Shall disable the Fast Role Swap receiver if this is enabled. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.4.4 PE_PRS_SNK_SRC_Transition_to_off State On entry to the PE_PRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Assert_Rp state when:  A PS_RDY Message is received. 8.3.3.19.4.5 PE_PRS_SNK_SRC_Assert_Rp State On entry to the PE_PRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.4.6 PE_PRS_SNK_SRC_Source_on State On entry to the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Source Port VBUS is at vSafe5V. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Page 900 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.4.7 PE_PRS_SNK_SRC_Send_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.4.8 PE_PRS_SNK_SRC_Reject_Swap State On entry to the PE_PRS_SNK_SRC_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 901 8.3.3.19.5 Policy Engine in Source to Sink Fast Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.178, "Dual-Role Port in Source to Sink Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Page 902 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.178 Dual-Role Port in Source to Sink Fast Role Swap State Diagram PE_SRC_Ready PE_FRS_SRC_SNK_ Evaluate_Swap Actions on entry: Ask Device Policy Manager if Fast Role Swap signaled on CC wire Power = Implicit Contract PD = Connected PE_FRS_SRC_SNK_ Transition_to_off Actions on entry: Wait for VBUS to reach vSafe5V Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Implicit Contract PD = Connected Fast Role Swap signaled Accept Message sent PS_RDY Message received PE_SNK_Startup PE_FRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Implicit contract PD = Connected VBUS at vSafe5V Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Accept Message not sent after retries (no GoodCRC received) PE_SRC_Hard_Reset FR_Swap Message received Fast Role Swap not signaled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 903 8.3.3.19.5.1 PE_SRC_Ready State The Fast Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Evaluate_Swap state when:  An FR_Swap Message is received. 8.3.3.19.5.2 PE_FRS_SRC_SNK_Evaluate_Swap State On entry to the PE_FRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether Fast Role Swap has been signaled on the CC wire. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Fast Role Swap has been signaled. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Device Policy Manager indicates that a Fast Role Swap is not being signaled. 8.3.3.19.5.3 PE_FRS_SRC_SNK_Accept_Swap State On entry to the PE_FRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Accept Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.5.4 PE_FRS_SRC_SNK_Transition_to_off State On entry to the PE_FRS_SRC_SNK_Transition_to_off state the Policy Engine Shall wait until VBUS has discharged to vSafe5V. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that VBUS has discharged to vSafe5V. 8.3.3.19.5.5 PE_FRS_SRC_SNK_Assert_Rd State On entry to the PE_FRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.5.6 PE_FRS_SRC_SNK_Wait_Source_on State On entry to the PE_FRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the New Source is now applying Rp. The Policy Engine Shall transition to the ErrorRecovery state when: Page 904 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 905 8.3.3.19.6 Policy Engine in Sink to Source Fast Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.179, "Dual-role Port in Sink to Source Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 906 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.179 Dual-role Port in Sink to Source Fast Role Swap State Diagram PE_FRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Power = Implicit Contract PD = Connected Fast Swap signal detected on CC Wire PE_FRS_SNK_SRC_ Send_Swap Actions on entry: Send FR_Swap Message Initialize and run SenderResponseTimer Power = Implicit Contract PD = Connected Accept Message received PE_FRS_SNK_SRC_ Source_on Actions on entry: Send PS_RDY Message Power = Transition to source on PD = Connected PS_RDY Message sent PE_SRC_Startup PE_FRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Implicit Contract PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout SenderResponseTimer timeout | FR_Swap Message not sent after retries (no GoodCRC received) PE_FRS_SNK_SRC_Vbus_Applied Actions on entry: Request Device Policy Manager to notify when vSafe5v is being applied by the local power source. Power = Implicit Contract PD = Connected New Source is applying vSafe5V PE_FRS_SNK_SRC_ Start_AMS Actions on entry: Notify the Protocol Layer that the first Message in the AMS will follow. Power = Implicit Contract PD = Connected Protocol Layer notified Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 907 8.3.3.19.6.1 PE_FRS_SNK_SRC_Start_AMS State The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Start_AMS state from any other state provided there is an Explicit Contract in place when:  The Sink Capabilities received from the Initial Source by the Policy Engine has at least one of the Fast Role Swap bits set.  The system has sufficient reserve power to provide the requested current to the Initial Source, as requested in the Fast Role Swap bits in the Sink Capabilities, and is willing to dedicate it to the Port  The Device Policy Manager indicates that a Fast Role Swap signal has been detected on the CC wire. On entry to the PE_FRS_SNK_SRC_Start_AMS state the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Send_Swap state when:  The Protocol Layer has been notified. 8.3.3.19.6.2 PE_FRS_SNK_SRC_Send_Swap State On entry to the PE_FRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send an FR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. The Policy Engine Shall transition to the ErrorRecovery state when:  The SenderResponseTimer times out or  The FR_Swap Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. 8.3.3.19.6.3 PE_FRS_SNK_SRC_Transition_to_off State On entry to the PE_FRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_VBUS_Applied state when:  A PS_RDY Message is received. 8.3.3.19.6.4 PE_FRS_SNK_SRC_VBUS_Applied State On entry to the PE_FRS_SNK_SRC_VBUS_Applied state the Policy Engine waits for a notification from the Device Policy Manager that the local power source has applied vSafe5V to VBUS (see Section 5.8.6.3, "Fast Role Swap Detection"). Note: This could have already been applied prior to entering this state or could be applied while waiting in this state. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Assert_Rp state when:  The Device Policy Manager indicates that vSafe5V is being applied. 8.3.3.19.6.5 PE_FRS_SNK_SRC_Assert_Rp State On entry to the PE_FRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. Page 908 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rp is asserted. 8.3.3.19.6.6 PE_FRS_SNK_SRC_Source_on State On entry to the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 909 8.3.3.19.7 Dual-Role (Source Port) Get Source Capabilities State Diagram Figure 8.180, "Dual-Role (Source) Get Source Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.180 Dual-Role (Source) Get Source Capabilities diagram 8.3.3.19.7.1 PE_DR_SRC_Get_Source_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap state, from the PE_SRC_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready State (see Figure 8.132, "Source Port State Diagram") when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. get source capabilities request from Device Policy Manager SPR Souce Capabilities requested & Source_Capabilities Message received | EPR Souce Capabilities requested & EPR_Source_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap Actions on entry: If SPR Source Capabilities requested Send Get_Source_Cap Message1 If EPR Source Capabilities requested Send EPR_Get_Source_Cap Message1 Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source capabilities/outcome to Device Policy Manager 1) Either SPR or EPR Source Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. Page 910 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.8 Dual-Role (Source Port) Give Sink Capabilities State Diagram Figure 8.181, "Dual-Role (Source) Give Sink Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a Get_Sink_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.181 Dual-Role (Source) Give Sink Capabilities diagram 8.3.3.19.8.1 PE_DR_SRC_Give_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap state, from the PE_SRC_Ready state, when a Get_Sink_Cap Message or EPR_Get_Sink_Cap Message is received.  On entry to the PE_DR_SRC_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Sink_Capabilities Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap_Ext Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 911 8.3.3.19.9 Dual-Role (Sink Port) Get Sink Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's Sink Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.182 Dual-Role (Sink) Get Sink Capabilities State Diagram 8.3.3.19.9.1 PE_DR_SNK_Get_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap state, from the PE_SNK_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SNK_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). If Fast Role Swap is supported, request Device Policy Manager prepare or disable 5V source and configure the Fast Role Swap receiver based on the Fast Role Swap required USB Type- C Current bits in the received Sink Capabilities. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager1 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Request Device Policy Manager to configure Fast Role Swap if supported 1) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Sink is currently operating in SPR or EPR Mode. Page 912 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.10 Dual-Role (Sink Port) Give Source Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.183 Dual-Role (Sink) Give Source Capabilities State Diagram 8.3.3.19.10.1 PE_DR_SNK_Give_Source_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap state, from the PE_SNK_Ready state, when a Get_Source_Cap Message is received.  On entry to the PE_DR_SNK_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities.  The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source Capabilities Message has been successfully sent. (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities Message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 913 8.3.3.19.11 Dual-Role (Source Port) Get Source Capabilities Extended State Diagram Figure 8.184, "Dual-Role (Source) Get Source Capabilities Extended State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.184 Dual-Role (Source) Get Source Capabilities Extended State Diagram 8.3.3.19.11.1 PE_DR_SRC_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Page 914 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.12 Dual-Role (Sink Port) Give Source Capabilities Extended State Diagram Figure 8.185, "Dual-Role (Sink) Give Source Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.185 Dual-Role (Sink) Give Source Capabilities Extended diagram 8.3.3.19.12.1 PE_DR_SNK_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_DR_SNK_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 915 8.3.3.19.13 Dual-Role (Sink Port) Get Sink Capabilities Extended State Dia- gram Figure 8.186, "Dual-Role (Sink) Get Sink Capabilities Extended State Diagram" shows the state diagram for a Dual- Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.186 Dual-Role (Sink) Get Sink Capabilities Extended State Diagram 8.3.3.19.13.1 PE_DR_SNK_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Sink_Capabilities_Extended Message is received.  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Sink extended capabilities/outcome to Device Policy Manager Page 916 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.14 Dual-Role (Source Port) Give Sink Capabilities Extended State Diagram Figure 8.187, "Dual-Role (Source) Give Sink Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.187 Dual-Role (Source) Give Sink Capabilities Extended diagram 8.3.3.19.14.1 PE_DR_SRC_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_DR_SRC_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Sink Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram")when:  The Sink_Capabilities_Extended Message has been successfully sent. _Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink Capabilities Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 917 8.3.3.19.15 Dual-Role (Source Port) Get Source Information State Diagram Figure 8.188, "Dual-Role (Source) Get Source Information State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.188 Dual-Role (Source) Get Source Information State Diagram 8.3.3.19.15.1 PE_DR_SRC_Get_Source_Info State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Info state, from the PE_SRC_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Info Message is received.  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Page 918 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.16 Dual-Role (Sink Port) Give Source Information State Diagram Figure 8.189, "Dual-Role (Source) Give Source Information diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.189 Dual-Role (Source) Give Source Information diagram 8.3.3.19.16.1 PE_DR_SNK_Give_Source_Info State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Info state, from the PE_SNK_Ready state, when a Get_Source_Info Message is received. On entry to the PE_DR_SNK_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 919 8.3.3.20 VCONN Swap State Diagram The State Diagram in this section Shall apply to Ports that supply VCONN. Figure 8.190, "VCONN Swap State Diagram" shows the state operation for a Port on sending or receiving a VCONN Swap request. Figure 8.190 VCONN Swap State Diagram 8.3.3.20.1 PE_VCS_Send_Swap State The PE_VCS_Send_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a request from the Device Policy Manager to perform a VCONN Swap. On entry to the PE_VCS_Send_Swap state the Policy Engine Shall send a VCONN_Swap Message and start the SenderResponseTimer. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  An Accept Message is received and  The Port is presently the VCONN Source. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  An Accept Message is received and  The Port is not presently the VCONN Source. PE_VCS_Evaluate_Swap Actions on entry: Get evaluation of VCONN swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_VCS_Turn_On_VCONN Actions on entry: Tell Device Policy Manager to turn on VCONN PE_VCS_Send_PS_Rdy Actions on entry: Send PS_RDY Message PE_VCS_Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected PE_VCS_Reject_VCONN_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent VCONN_Swap Message received VCONN Swap ok (Not Presently VCONN SOURCE & VCONN Swap not ok) | Further evaluation Required Accept Message sent & Not presently VCONN Source1 VCONN turned on PS_RDY Message sent VCONNOnTimer Timeout Hard Reset: Consumer/Provider -> PE_SNK_Hard_Reset Provider/Consumer -> PE_SRC_Hard_Reset Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_VCS_Wait_for_VCONN Actions on entry: Start VCONNOnTimer Power = Explicit Contract PD = Connected Accept Message sent & Presently VCONN Source1 PE_VCS_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = Connected PS_RDY Message received Device Policy Manager Informed VCONN Swap required (indication from Device Policy Manager) PE_VCS_Send_Swap Actions on entry: Send VCONN_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout Accept Message received & Presently VCONN Source1 Accept Message received & Not presently VCONN Source1 PE_VCS_Force_VCONN2 Actions on entry: Tell Device Policy Manager to turn on VCONN Power = Explicit Contract PD = Connected Not_Supported Message received & Not presently VCONN Source1 VCONN turned on PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Entry_ACK PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_SNK_EPR_Mode_Entry_Wait_For_Response PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable 1) A Port is presently the VCONN Source if it has the responsibility for supplying VCONN even if VCONN has been turned off. 2) The PE_VCS_Force_VCONN state is Optional. Page 920 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  A Reject Message is received or  A Wait Message is received or  The SenderResponseTimer times out. The Policy Engine May transition to the PE_VCS_Force_VCONN state when:  A Not_Supported Message is received and  The Port is not presently the VCONN Source. 8.3.3.20.2 PE_VCS_Evaluate_Swap State The PE_VCS_Evaluate_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a VCONN_Swap Message. On entry to the PE_VCS_Evaluate_Swap state the Policy Engine Shall request the Device Policy Manager for an evaluation of the VCONN Swap request. The Policy Engine Shall transition to the PE_VCS_Accept_Swap state when:  The Device Policy Manager indicates that a VCONN Swap is OK. The Policy Engine Shall transition to the PE_VCS_Reject_Swap state when:  The Port is not presently the VCONN Source and the Device Policy Manager indicates that a VCONN Swap is not OK or  The Device Policy Manager indicates that a VCONN Swap cannot be done at this time. 8.3.3.20.3 PE_VCS_Accept_Swap State On entry to the PE_VCS_Accept_Swap state the Policy Engine Shall send an Accept Message. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is on. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is off. 8.3.3.20.4 PE_VCS_Reject_Swap State On entry to the PE_VCS_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a VCONN Swap at this time.  A Wait Message if further evaluation of the VCONN Swap request is required. Note: In this case it is expected that the Port will send a VCONN_Swap Message at a later time. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 921 8.3.3.20.5 PE_VCS_Wait_for_VCONN State On entry to the PE_VCS_Wait_For_VCONN state the Policy Engine Shall start the VCONNOnTimer. The Policy Engine Shall transition to the PE_VCS_Turn_Off_VCONN state when:  A PS_RDY Message is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state when:  The VCONNOnTimer times out. 8.3.3.20.6 PE_VCS_Turn_Off_VCONN State On entry to the PE_VCS_Turn_Off_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Device Policy Manager has been informed. 8.3.3.20.7 PE_VCS_Turn_On_VCONN State On entry to the PE_VCS_Turn_On_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition to the PE_VCS_Send_Ps_Rdy state when:  The Port's VCONN is on. 8.3.3.20.8 PE_VCS_Send_PS_Rdy State On entry to the PE_VCS_Send_Ps_Rdy state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The PS_RDY Message has been sent. 8.3.3.20.9 PE_VCS_Force_VCONN State On entry to the PE_VCS_Force_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Port's VCONN is on. 8.3.3.21 Initiator Structured VDM State Diagrams The State Diagrams in this section Shall apply to all Initiators. Page 922 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.1 Initiator Structured VDM Discover Identity State Diagram Figure 8.191, "Initiator to Port VDM Discover Identity State Diagram" shows the state diagram for an Initiator when discovering the identity of its Port Partner or Cable Plug. Figure 8.191 Initiator to Port VDM Discover Identity State Diagram 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_Request State The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the identity of the Port Partner or Cable Plug or  The DiscoverIdentityTimer times out. The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from the PE_SRC_EPR_Mode_Discover_Cable state when:  The Cable Plug Discovery Process has been initiated. PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_INIT_PORT_VDM_Identity_Request Actions on entry: Send Discover Identity request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests identity discovery1 | DiscoverIdentityTimer timeout Discover Identity ACK received PE_INIT_PORT_VDM_Identity_ACKed Actions on entry: Inform DPM of identity Power = Explicit Contract PD = Connected PE_INIT_PORT_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR 1) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 923 On entry to the PE_INIT_PORT_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out. 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_ACKed State On entry to the PE_INIT_PORT_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. 8.3.3.21.1.3 PE_INIT_PORT_VDM_Identity_NAKed State On entry to the PE_INIT_PORT_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. Page 924 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.2 Initiator Structured VDM Discover SVIDs State Diagram Figure 8.192, "Initiator VDM Discover SVIDs State Diagram" shows the state diagram for an Initiator when discovering SVIDs of its Port Partner or Cable Plug. Figure 8.192 Initiator VDM Discover SVIDs State Diagram 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_Request State The Policy Engine transitions to the PE_INIT_VDM_SVIDs_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the SVIDs of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_SVIDs_Request state the Policy Engine Shall send a Structured VDM Discover SVIDs Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_ACKed state when:  A Structured VDM Discover SVIDs ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_NAKed state when:  A Structured VDM Discover SVIDs NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_SVIDs_Request Actions on entry: Send Discover SVIDs request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests SVIDs discovery Discover SVIDs ACK received PE_INIT_VDM_SVIDs_ACKed Actions on entry: Inform DPM of SVIDs Power = Explicit Contract PD = Connected PE_INIT_VDM_SVIDs_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover SVIDs NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 925 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_ACKed State On entry to the PE_INIT_VDM_SVIDs_ACKed state the Policy Engine Shall inform the Device Policy Manager of the SVIDs information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. 8.3.3.21.2.3 PE_INIT_VDM_SVIDs_NAKed State On entry to the PE_INIT_VDM_SVIDs_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. Page 926 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.3 Initiator Structured VDM Discover Modes State Diagram Figure 8.193, "Initiator VDM Discover Modes State Diagram" shows the state diagram for an Initiator when discovering Modes of its Port Partner or Cable Plug. Figure 8.193 Initiator VDM Discover Modes State Diagram 8.3.3.21.3.1 PE_INIT_VDM_Modes_Request State The Policy Engine transitions to the PE_INIT_VDM_Modes_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the Modes of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_Modes_Request state the Policy Engine Shall send a Structured VDM Discover Modes Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_ACKed state when:  A Structured VDM Discover Modes ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_NAKed state when:  A Structured VDM Discover Modes NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Modes_Request Actions on entry: Send Discover Modes request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests Modes discovery Discover Modes ACK received PE_INIT_VDM_Modes_ACKed Actions on entry: Inform DPM of Modes Power = Explicit Contract PD = Connected PE_INIT_VDM_Modes_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Modes NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 927 8.3.3.21.3.2 PE_INIT_VDM_Modes_ACKed State On entry to the PE_INIT_VDM_Modes_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Modes information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. 8.3.3.21.3.3 PE_INIT_VDM_Modes_NAKed State On entry to the PE_INIT_VDM_Modes_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Page 928 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.4 Initiator Structured VDM Attention State Diagram Figure 8.194, "Initiator VDM Attention State Diagram" shows the state diagram for an Initiator when sending an Attention Command request. Figure 8.194 Initiator VDM Attention State Diagram 8.3.3.21.4.1 PE_INIT_VDM_Attention_Request State The Policy Engine transitions to the PE_INIT_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  When the Device Policy Manager requests attention from its Port Partner. On entry to the PE_INIT_VDM_Attention_Request state the Policy Engine Shall send an Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Attention Command request has been sent. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Attention_Request Actions on entry: Send Attention Command request Power = Explicit Contract PD = Connected Attention request from DPM Attention Command request sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 929 8.3.3.22 Responder Structured VDM State Diagrams 8.3.3.22.1 Responder Structured VDM Discover Identity State Diagram Figure 8.195, "Responder Structured VDM Discover Identity State Diagram" shows the state diagram for a Responder receiving a Discover Identity Command request. Figure 8.195 Responder Structured VDM Discover Identity State Diagram 8.3.3.22.1.1 PE_RESP_VDM_Get_Identity State The Policy Engine transitions to the PE_RESP_VDM_Get_Identity state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Identity Command request is received. On entry to the PE_RESP_VDM_Get_Identity state the Responder Shall request identity information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Identity state when:  Identity information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Identity_NAK state when:  The Device Policy Manager indicates that the response to the Discover Identity Command request is NAK or BUSY. 8.3.3.22.1.2 PE_RESP_VDM_Send_Identity State On entry to the PE_RESP_VDM_Send_Identity state the Responder Shall send the Structured VDM Discover Identity ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Discover Identity ACK Command response has been sent. 8.3.3.22.1.3 PE_RESP_VDM_Get_Identity_NAK State On entry to the PE_RESP_VDM_Get_Identity_NAK state the Policy Engine Shall send a Structured VDM Discover Identity NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Identity NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Identity Actions on entry: Send Discover Identity ACK Power = Explicit Contract PD = Connected Discover Identity request Discover Identity ACK sent PE_RESP_VDM_Get_Identity Actions on entry: Request Identity information from DPM Power = Explicit Contract PD = Connected Identity information from DPM PE_RESP_VDM_Get_Identity_NAK Actions on entry: Send Discover Identity NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Identity NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 930 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.2 Responder Structured VDM Discover SVIDs State Diagram Figure 8.196, "Responder Structured VDM Discover SVIDs State Diagram" shows the state diagram for a Responder when receiving a Discover SVIDs Command. Figure 8.196 Responder Structured VDM Discover SVIDs State Diagram 8.3.3.22.2.1 PE_RESP_VDM_Get_SVIDs State The Policy Engine transitions to the PE_RESP_VDM_Get_SVIDs state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover SVIDs Command request is received. On entry to the PE_RESP_VDM_Get_SVIDs state the Responder Shall request SVIDs information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_SVIDs state when:  SVIDs information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_SVIDs_NAK state when:  The Device Policy Manager indicates that the response to the Discover SVIDs Command request is NAK or BUSY. 8.3.3.22.2.2 PE_UFP_VDM_Send_SVIDs State On entry to the PE_RESP_VDM_Send_SVIDs state the Responder Shall send the Structured VDM Discover SVIDs ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs ACK Command response has been sent. 8.3.3.22.2.3 PE_UFP_VDM_Get_SVIDs_NAK State On entry to the PE_RESP_VDM_Get_SVIDs_NAK state the Policy Engine Shall send a Structured VDM Discover SVIDs NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_SVIDs Actions on entry: Send Discover SVIDs ACK Power = Explicit Contract PD = Connected Discover SVIDs request Discover SVIDs ACK sent PE_RESP_VDM_Get_SVIDs Actions on entry: Request SVIDs information from DPM Power = Explicit Contract PD = Connected SVIDs information from DPM PE_RESP_VDM_Get_SVIDs_NAK Actions on entry: Send Discover SVIDs NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover SVIDs NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 931 8.3.3.22.3 Responder Structured VDM Discover Modes State Diagram Figure 8.197, "Responder Structured VDM Discover Modes State Diagram" shows the state diagram for a Responder on receiving a Discover Modes Command. Figure 8.197 Responder Structured VDM Discover Modes State Diagram 8.3.3.22.3.1 PE_RESP_VDM_Get_Modes State The Policy Engine transitions to the PE_RESP_VDM_Get_Modes state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Modes Command request is received. On entry to the PE_RESP_VDM_Get_Modes state the Responder Shall request Modes information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Modes state when:  Modes information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Modes_NAK state when:  The Device Policy Manager indicates that the response to the Discover Modes Command request is NAK or BUSY. 8.3.3.22.3.2 PE_RESP_VDM_Send_Modes State On entry to the PE_RESP_VDM_Send_Modes state the Responder Shall send the Structured VDM Discover Modes ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes ACK Command response has been sent. 8.3.3.22.3.3 PE_RESP_VDM_Get_Modes_NAK State On entry to the PE_RESP_VDM_Get_Modes_NAK state the Policy Engine Shall send a Structured VDM Discover Modes NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Modes Actions on entry: Send Discover Modes ACK Power = Explicit Contract PD = Connected Discover Modes request Discover Modes ACK sent PE_RESP_VDM_Get_Modes Actions on entry: Request Modes information from DPM Power = Explicit Contract PD = Connected Modes information from DPM PE_RESP_VDM_Get_Modes_ NAK Actions on entry: Send Discover Modes NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Modes NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 932 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.4 Receiving a Structured VDM Attention State Diagram Figure 8.198, "Receiving a Structured VDM Attention State Diagram" shows the state diagram when receiving an Attention Command request. Figure 8.198 Receiving a Structured VDM Attention State Diagram 8.3.3.22.4.1 PE_RCV_VDM_Attention_Request State The Policy Engine transitions to the PE_RCV_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  An Attention Command request is received. On entry to the PE_RCV_VDM_Attention_Request state the Policy Engine Shall inform the Device Policy Manager of the Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. PE_SRC_Ready or PE_SNK_Ready PE_RCV_VDM_Attention_Request Actions on entry: Inform Device Policy Manager of Attention Command request Power = Explicit Contract PD = Connected Attention Command request received DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 933 8.3.3.23 DFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all DFPs that support Structured VDMs. 8.3.3.23.1 DFP Structured VDM Mode Entry State Diagram Figure 8.199, "DFP VDM Mode Entry State Diagram" shows the state operation for a DFP when entering a Mode. Figure 8.199 DFP VDM Mode Entry State Diagram 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Entry_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug enter a Mode. On entry to the PE_DFP_VDM_Mode_Entry_Request state the Policy Engine Shall send a Structured VDM Enter Mode Command request and Shall start the VDMModeEntryTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Enter Mode ACK Command response is received. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_NAKed state when:  A Structured VDM Enter Mode NAK or BUSY Command response is received or  The VDMModeEntryTimer times out. PE_SRC_Ready or PE_SNK_Ready (DFP) DPM requests Mode entry1 PE_DFP_VDM_Mode_Entry_ACKed Actions on entry: Request DPM to enter the mode Power = Explicit Contract PD = Connected PE_DFP_VDM_Mode_Entry_Request Actions on entry: Send Mode Entry request Start VDMModeEntryTimer Power = Explicit Contract PD = Connected Mode Entry ACK received Mode entered PE_DFP_VDM_Mode_Entry_NAKed Actions on entry: Inform DPM of reason for failure Power = Explicit Contract PD = Connected Mode Entry NAK/BUSY Received | VDMModeEntryTimer timeout | Protocol Error3 DPM informed2 1) The Device Policy Manager Shall have placed the system into USB Safe State before issuing this request when entering Modal operation. 2) The Device Policy Manager Shall have returned the system to USB operation if not in Modal operation at this point. 3) Protocol Errors are handled by informing the DPM, returning to USB Safe State and then processing the Message once the PE_SRC_Ready or PE_SNK_Ready state has been entered. Page 934 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_ACKed State On entry to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall request the Device Policy Manager to enter the Mode. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Mode has been entered. 8.3.3.23.1.3 PE_DFP_VDM_Mode_Entry_NAKed State On entry to the PE_DFP_VDM_Mode_Entry_NAKed state the Policy Engine Shall inform the Device Policy Manager of the reason for failure (NAK, BUSY, timeout or Protocol Error). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 935 8.3.3.23.2 DFP Structured VDM Mode Exit State Diagram Figure 8.200, "DFP VDM Mode Exit State Diagram" shows the state diagram for a DFP when exiting a Mode. Figure 8.200 DFP VDM Mode Exit State Diagram 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Exit_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug exit a Mode. On entry to the PE_DFP_VDM_Mode_Exit_Request state the Policy Engine Shall send a Structured VDM Exit Mode Command request and Shall start the VDMModeExitTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Exit Mode ACK or NAK Command response is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state depending on the present Power Role when:  A Structured VDM Exit Mode BUSY Command response is received or  The VDMModeExitTimer times out. 8.3.3.23.2.2 PE_DFP_VDM_DFP_Mode_Exit_ACKed State On Exit to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall inform the Device Policy Manager Of the result: ACK or NAK. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when: PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DFP_VDM_Mode_Exit_Request Actions on entry: Send Exit Mode request Start VDMModeExitTimer Power = Explicit Contract PD = Connected DPM indicates Mode exit PE_DFP_VDM_Exit_Mode_ACKed Actions on entry: Inform DPM of ACK or NAK Power = Explicit Contract PD = Connected Exit Mode ACK/NAK received DPM informed1 PE_SRC_Hard_Reset or PE_SNK_Hard_Reset (DFP) Exit Mode BUSY Received | VDMModeExitTimer Timeout 1) The Device Policy Manager is required to return the system to USB operation at this point when exiting Modal Operation. Page 936 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 937 8.3.3.24 UFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all UFPs that support Structured VDMs. 8.3.3.24.1 UFP Structured VDM Enter Mode State Diagram Figure 8.201, "UFP Structured VDM Enter Mode State Diagram" shows the state diagram for a UFP in response to an Enter Mode Command. Figure 8.201 UFP Structured VDM Enter Mode State Diagram 8.3.3.24.1.1 PE_UFP_VDM_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_UFP_VDM_Evaluate_Mode_Entry state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_UFP_VDM_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected Enter Modes request1 PE_UFP_VDM_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_UFP_VDM_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_UFP_VDM_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 938 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_ACK State On entry to the PE_UFP_VDM_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.24.1.3 PE_UFP_VDM_Mode_Entry_NAK State On entry to the PE_UFP_VDM_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 939 8.3.3.24.2 UFP Structured VDM Exit Mode State Diagram Figure 8.202, "UFP Structured VDM Exit Mode State Diagram" shows the state diagram for a UFP in response to an Exit Mode Command. Figure 8.202 UFP Structured VDM Exit Mode State Diagram 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit State The Policy Engine transitions to the PE_UFP_VDM_Mode_Exit state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_UFP_VDM_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. PE_UFP_VDM_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Power = Explicit Contract PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_UFP_VDM_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Power = Explicit Contract PD = Connected Mode exited PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected PE_UFP_VDM_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Power = Explicit Contract PD = Connected DPM says NAK Exit Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 940 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_ACK State On entry to the PE_UFP_VDM_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.24.2.3 PE_UFP_VDM_Mode_Exit_NAK State On entry to the PE_UFP_VDM_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 941 8.3.3.25 Cable Plug Specific State Diagrams The State Diagrams in this section Shall apply to all Cable Plugs that support Structured VDMs. 8.3.3.25.1 Cable Plug Cable Ready State Diagram Figure 8.203, "Cable Ready State Diagram" shows the Cable Ready state diagram for a Cable Plug. Figure 8.203 Cable Ready State Diagram 8.3.3.25.1.1 PE_CBL_Ready State The PE_CBL_Ready state shown in the following sections is the normal operational state for a Cable Plug and where it starts after power up or a Hard/Cable Reset. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Power up | Hard Reset Complete | Cable Reset Complete Page 942 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2 Soft/Hard/Cable Reset 8.3.3.25.2.1 Cable Plug Soft Reset State Diagram Figure 8.204, "Cable Plug Soft Reset State Diagram" shows the Cable Plug state diagram on reception of a Soft_Reset Message. Figure 8.204 Cable Plug Soft Reset State Diagram 8.3.3.25.2.1.1 PE_CBL_Soft_Reset State The PE_CBL_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received from the Protocol Layer. On entry to the PE_CBL_Soft_Reset state the Policy Engine Shall reset the Protocol Layer in the Cable Plug and Shall then request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Accept Message has been sent or  The Protocol Layer indicates that a transmission error has occurred. Accept Message sent | Transmission Error indication from Protocol Layer Soft Reset Message received PE_CBL_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept Message Cable = Awake PD = Connected PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 943 8.3.3.25.2.2 Cable Plug Hard Reset State Diagram Figure 8.205, "Cable Plug Hard Reset State Diagram" shows the Cable Plug state diagram for a Hard Reset or Cable Reset. Figure 8.205 Cable Plug Hard Reset State Diagram 8.3.3.25.2.2.1 PE_CBL_Hard_Reset State The PE_CBL_Hard_Reset state Shall be entered from any state when either Hard Reset Signaling or Cable Reset Signaling is detected. On entry to the PE_CBL_Hard_Reset state the Policy Engine Shall reset the Cable Plug (equivalent to a power cycle). The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Cable Plug reset is complete. Hard Reset signalling Received | Cable Reset Command PE_CBL_Hard_Reset Actions on entry: Reset Cable Plug Cable = Awake/Asleep PD = Not Connected Cable reset complete PE_CBL_Ready Page 944 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.3 DFP/VCONN Source SOP'/SOP'' Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram Figure 8.206, "DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the Policy Engine in a VCONN Source when performing a Soft Reset or Cable Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.206 DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Soft_Reset State The PE_DFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_DFP_VCS_CBL_Send_Soft_Reset state the DFP Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug/VPD, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the DFP VCONN Source's Power Role, when:  There is no Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Send_Capabilities state or PE_SRC_Discovery state, depending on the DFP's VCONN Source's Power Role, when:  There is an Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to the PE_DFP_VCS_CBL_Send_Cable_Reset state when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_DFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered| Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error In Explicit Contract & Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_DFP_VCS_CBL_Send_Cable_Reset Actions on entry: Send Cable Reset Message Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Cable Reset Request from Device Policy Manager Cable Reset sent PE_SRC_Send_Capabilities or PE_SRC_Discovery2 (VCONN Source) Not in Explicit Contract & Accept Message Received on SOP’/SOP’’ 1) Excludes the Soft_Reset Message itself. 2) Sink only communicates with the Cable Plug when in an Explicit Contract. If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 945 8.3.3.25.2.3.2 PE_DFP_VCS_CBL_Send_Cable_Reset State The PE_DFP_VCS_CBL_Send_Cable_Reset state Shall be entered from any state when the Device Policy Manager requests a Cable Reset. On entry to the PE_DFP_VCS_CBL_Send_Cable_Reset state the DFP Policy Engine Shall request the Protocol Layer to send Cable Reset Signaling. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the VCONN Source's Power Role, when:  Cable Reset Signaling has been sent. Page 946 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.4 UFP/VCONN Source SOP'/SOP'' Soft Reset of a Cable Plug or VPD State Diagram Figure 8.207, "UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the UFP Policy Engine in a VCONN Source when performing a Soft Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.207 UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.4.1 PE_UFP_VCS_CBL_Send_Soft_Reset State The PE_UFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_UFP_VCS_CBL_Send_Soft_Reset state the Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the UFP VCONN Source's Power Role, when:  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state, depending on the UFP VCONN Source's Power Role, when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_UFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered | Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_SRC_Hard_Reset or PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 947 8.3.3.25.3 Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" shows the state diagram for Source discovery of identity information from a Cable Plug during the startup sequence. Figure 8.208 Source Startup Structured VDM Discover Identity State Diagram 8.3.3.25.3.1 PE_SRC_VDM_Identity_Request State The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Startup state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Discovery state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug and  The DiscoverIdentityCounter < nDiscoverIdentityCount. Even though there has been a transition out of the PE_SRC_Discovery state the SourceCapabilityTimer Shall continue to run during the states shown in Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" and Shall Not be initialized on re-entry to PE_SRC_Discovery. PE_SRC_Send_Capabilities or PE_SRC_Discovery1 PE_SRC_VDM_Identity_Request Actions on entry: Send Discover Identity request Increment the DiscoverIdentityCounter Start VDMResponseTimer Power = No or Implicit Contract Cable Plug = Not PD Connected DPM requests identity discovery3 & Protocol Layer Reset Complete Discover Identity ACK received PE_SRC_VDM_Identity_ACKed Actions on entry: Inform DPM of identity PE_SRC_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power =No or Implicit Contract Cable Plug = PD Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout | Discover Identity request sending failure (without GoodCRC) DPM informed DPM informed PE_SRC_Startup DPM requests identity discovery & DiscoverIdentityCounter < nDiscoverIdentityCount2 PE_SRC_Discovery Power = No or Implicit Contract Cable Plug = PD Connected 1) If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. 2) The SourceCapabilityTimer continues to run during the states defined in this diagram even though there has been an exit from the PE_SRC_Discovery state. This ensures that Source_Capabilities Messages are sent out at a regular rate. 3) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Page 948 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: An EPR Source is required to discover the identity of the Cable Plug prior to entering the First Explicit Contract (see Section 6.4.10.1, "Process to enter EPR Mode") On entry to the PE_SRC_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request, Shall increment the DiscoverIdentityCounter and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out or  The Structured VDM Discover Identity Command request Message sending fails (no GoodCRC Message received after retries). 8.3.3.25.3.2 PE_SRC_VDM_Identity_ACKed State On entry to the PE_SRC_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. 8.3.3.25.3.3 PE_SRC_VDM_Identity_NAKed State On entry to the PE_SRC_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 949 8.3.3.25.4 Cable Plug Mode Entry/Exit 8.3.3.25.4.1 Cable Plug Structured VDM Enter Mode State Diagram Figure 8.209, "Cable Plug Structured VDM Enter Mode State Diagram" shows the state diagram for a Cable Plug in response to an Enter Mode Command. Figure 8.209 Cable Plug Structured VDM Enter Mode State Diagram 8.3.3.25.4.1.1 PE_CBL_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_CBL_Evaluate_Mode_Entry state from the PE_CBL_Ready state when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_CBL_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_ACK State On entry to the PE_CBL_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Enter Modes request1 PE_CBL_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_CBL_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_CBL_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 950 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.25.4.1.3 PE_CBL_Mode_Entry_NAK State On entry to the PE_CBL_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 951 8.3.3.25.4.2 Cable Plug Structured VDM Exit Mode State Diagram Figure 8.210, "Cable Plug Structured VDM Exit Mode State Diagram" shows the state diagram for a Cable Plug in response to an Exit Mode Command. Figure 8.210 Cable Plug Structured VDM Exit Mode State Diagram 8.3.3.25.4.2.1 PE_CBL_Mode_Exit State The Policy Engine transitions to the PE_CBL_Mode_Exit state from the PE_CBL_Ready state when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_CBL_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_ACK State On entry to the PE_CBL_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. PE_CBL_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Cable = Awake PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_CBL_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Cable = Awake PD = Connected Mode exited PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected PE_CBL_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Cable = Awake PD = Connected DPM says NAK Exit Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 952 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.25.4.2.3 PE_CBL_Mode_Exit_NAK State On entry to the PE_CBL_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 953 8.3.3.26 EPR Mode State Diagrams 8.3.3.26.1 Source EPR Mode Entry State Diagram Figure 8.211, "Source EPR Mode Entry State Diagram" shows the state diagram for an EPR Source in response to an EPR_Mode Message. Figure 8.211 Source EPR Mode Entry State Diagram 8.3.3.26.1.1 PE_SRC_Evaluate_EPR_Mode_Entry State The Policy Engine transitions to the PE_SRC_Evaluate_EPR_Mode_Entry state from the PE_SRC_Ready state when:  An EPR_Mode (Enter) Message is received from the Sink. On Entry to the PE_SRC_Evaluate_EPR_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the EPR_Mode (Enter) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Ack state when:  The Device Policy Manager indicates that EPR Mode can be entered. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Device Policy Manager indicates that the EPR Mode is not to be entered. EPR_Mode (Enter) received PE_SRC_EPR_Mode_Entry_ACK Actions on entry: Send EPR Enter Mode Acknowledge If Source is not the VCONN Source initiate VCONN Swap process PE_SRC_Evaluate_EPR Mode_Entry Actions on entry: Request DPM to evaluate request to enter EPR Mode Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Failed Actions on entry: Send Enter Mode (Enter Failed) with appropriate failure code. DPM says enter EPR Mode EPR Enter Mode (Enter Failed) sent PE_SRC_Ready PE_VCS_Send_Swap PE_VCS_Force_VCONN or PE_VCS_Send_PS_RDY VCONN Swap Process DPM says don’t enter EPR Mode PE_SRC_EPR_Mode_Discover_Cable Actions on entry: Check Vconn Swap Result if Vconn Swap Process carried out. Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected EPR Enter Mode (Enter Acknowledged) Sent & Source is VCONN Source & Unknown Cable PE_INIT_PORT_VDM_Identity_Request PE_INIT_PORT_VDM_Identity_ACKed or PE_INIT_PORT_VDM_Identity_NAKed Source is the VCONN Source Cable Discovery Process PE_SRC_EPR_Mode_Evaluate_Cable_EPR Actions on entry: Ask DPM to evaluate Cable Discovery results Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Succeeded Actions on entry: Send EPR Mode (Enter Succeeded) Enter EPR Mode. Power = Explicit Contract PD = Connected VCONN Swap Process Complete Cable Discovery Process Complete Cable Plug is EPR capable PE_SRC_Send_Capabilities EPR Mode Entered Cable Plug is not EPR capable EPR Enter Mode (Enter Acknowledged) Sent & (captive cable | known EPR Capable Cable) EPR Enter Mode (Enter Acknowledged) Sent & Source is not VCONN Source & Unknown Cable Page 954 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.1.2 PE_SRC_EPR_Mode_Entry_Ack State On entry to the PE_SRC_EPR_Mode_Entry_Ack state the Policy Engine Shall send a EPR_Mode (Enter Acknowledged) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is a captive cable or a known EPR Cable. The Policy Engine Shall transition to the PE_VCS_Send_Swap state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is unknown. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Discover_Cable state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is the VCONN Source and  The cable is unknown. 8.3.3.26.1.3 PE_SRC_EPR_Mode_Discover_Cable State The Policy Engine transitions to the PE_SRC_EPR_Mode_Discover_Cable state from the PE_VCS_Force_VCONN state or PE_VCS_Send_Ps_Rdy state when:  A Source initiated VCONN Swap process has completed. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_Request state in order to perform Cable Plug discovery when:  The Source is the VCONN Source. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The VCONN Swap process failed (the Source is not the VCONN Source). 8.3.3.26.1.4 PE_SRC_EPR_Mode_Evaluate_Cable_EPR State In the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state the Policy Engine requests the DPM to evaluate the Cable Discovery results. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Succeeded state when:  The Cable Plug is capable of EPR Mode. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Cable Plug is not capable of EPR Mode. 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Succeeded State On entry to the PE_SRC_EPR_Mode_Entry_Succeeded state the Policy Engine Shall send a EPR_Mode (Enter Succeeded) Message and enter EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  EPR Mode has been entered. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 955 8.3.3.26.1.6 PE_SRC_EPR_Mode_Entry_Failed State On entry to the PE_SRC_EPR_Mode_Entry_Failed state the Policy Engine Shall send a EPR_Mode (Enter Failed) Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_Mode (Enter Failed) Message has been sent. Page 956 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.2 Sink EPR Mode Entry State Diagram Figure 8.212, "Sink EPR Mode Entry State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode Entry process. Figure 8.212 Sink EPR Mode Entry State Diagram 8.3.3.26.2.1 PE_SNK_Send_EPR_Mode_Entry State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Entry state from the PE_SNK_Ready state when:  The DPM requests entry into EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Entry state the Policy Engine Shall send an EPR_Mode (Enter) Message and starts the SenderResponseTimer and the SinkEPREnterTimer. Note: The SinkEPREnterTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SNK_EPR_Mode_Wait_For_Response state when:  An EPR_Mode (Enter Acknowledge) Message is received. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or DPM Request EPR Mode Entry PE_SNK_EPR_Mode_Entry_Wait_For_Response Actions on entry: Wait for EPR Enter Mode response PE_SNK_Send_EPR Mode_Entry Actions on entry: Send EPR Mode Entry Message Start SenderResponse Timer Start SinkEPREnterTimer Power = Explicit Contract PD = Connected EPR Enter Mode Acknowledge received PE_SNK_Ready EPR Enter Mode Succeeded received Power = Explicit Contract PD = Connected PE_SNK_Send_Soft_Reset EPR Enter Mode received (!Succceded) | SenderResponseTimer timeout | SinkEPREnterTimer timeout EPR Enter Mode received (!Succceded) | SinkEPREnterTimer timeout Actions on exit: Stop the SinkEPRTimer Enter EPR Mode PE_SNK_Wait_For_Capabilities PE_VCS_Evaluate_Swap VCONN Swap Process VCONN_Swap Message Received VCONN Swap Process completed PE_VCS_Turn_Off_VCONN Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 957  The SenderResponseTimer times out or  The SinkEPREnterTimer times out. 8.3.3.26.2.2 PE_SNK_EPR_Mode_Wait_For_Response State In the State the Policy Engine waits for a confirmation that the EPR Mode entry request has succeeded. On exit from the PE_SNK_EPR_Mode_Wait_For_Response state the Policy Engine Shall stop the SinkEPREnterTimer and enter EPR Mode. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or  The SinkEPREnterTimer times out. The Policy Engine Shall transition to the PE_VCS_Evaluate_Swap State when:  A VCONN_Swap Message is received. The Policy Engine Shall transition back from the PE_VCS_Turn_Off_VCONN State to the PE_SNK_EPR_Mode_Wait_For_Response State when:  The VCONN Swap process has completed. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An EPR_Mode (Enter Succeeded) Message has been received. Page 958 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.3 Source EPR Mode Exit State Diagram Figure 8.213, "Source EPR Mode Exit State Diagram" shows the state diagram for an EPR Source initiating the EPR Mode exit process. Figure 8.213 Source EPR Mode Exit State Diagram 8.3.3.26.3.1 PE_SRC_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SRC_Send_EPR_Mode_Exit state from the PE_SRC_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.3.2 PE_SRC_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SRC_EPR_Mode_Exit_Received state from the PE_SRC_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SRC_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SRC_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SRC_Ready Actions on exit: Exit EPR Mode PE_SRC_Send_Capabilities PE_SRC_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explict Contract with SPR PDO & EPR Mode Exited PE_SRC_Hard_Reset Not in an Explicit Contract with an SPR PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 959 8.3.3.26.4 Sink EPR Mode Exit State Diagram Figure 8.214, "Sink EPR Mode Exit State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode exit process. Figure 8.214 Sink EPR Mode Exit State Diagram 8.3.3.26.4.1 PE_SNK_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Exit state from the PE_SNK_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.4.2 PE_SNK_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SNK_EPR_Mode_Exit_Received state from the PE_SNK_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SNK_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SNK_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SNK_Ready Actions on exit: Exit EPR Mode PE_SNK_Wait_for_Capabilities PE_SNK_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explicit Contract with SPR PDO & EPR Mode Exited PE_SNK_Hard_Reset Not in an Explicit Contract with an SPR PDO Page 960 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27 BIST State diagrams 8.3.3.27.1 BIST Carrier Mode State Diagram Figure 8.215, "BIST Carrier Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Carrier Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.215 BIST Carrier Mode State Diagram 8.3.3.27.1.1 PE_BIST_Carrier_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Carrier_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Carrier Mode BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Carrier_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Carrier Mode (see Section 6.4.3.1, "BIST Carrier Mode") and Shall initialize and run the BISTContModeTimer. BIST message received with Data Object BIST Carrier Mode & VBUS = vSafe5V BISTContModeTimer timeout PE_BIST_Carrier_Mode Actions on entry: Tell Protocol Layer to go to BIST Carrier Mode Initialize and run BISTContModeTimer PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 961 The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  The BISTContModeTimer times out. Page 962 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.2 BIST Test Data Mode State Diagram Figure 8.216, "BIST Test Data Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Test Data Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.216 BIST Test Data Mode State Diagram 8.3.3.27.2.1 PE_BIST_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Test Data BIST Data Object and  VBUS is at vSafe5V. BIST message received with Data Object BIST Test Mode & VBUS = vSafe5V Hard Reset PE_BIST_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Test Mode PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 963 On entry to the PE_BIST_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go into BIST Test Data Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A Hard Reset occurs. Page 964 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.3 BIST Shared Capacity Test Mode State Diagram Figure 8.217, "BIST Shared Capacity Test Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Shared Capacity Test Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.217 BIST Shared Capacity Test Mode State Diagram 8.3.3.27.3.1 PE_BIST_Shared_Capacity_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Shared_Capacity_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Shared Test Mode Entry BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Shared_Capacity_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Shared Capacity Test Mode (see Section 6.4.3.3, "BIST Shared Capacity Test Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A BIST Message is received with a BIST Shared Test Mode Exit BIST Data Object. BIST message received with Data Object BIST Shared Test Mode Entry BIST message received with Data Object BIST Shared Test Mode Exit PE_BIST_Shared Capacity_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Shared Capacity Test Mode1. PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected 1) The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off. The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs: Hard Reset, Cable Reset, Soft Reset, Data Role Swap, Power Role Swap, Fast Role Swap, VCONN Swap. The UUT May leave test mode if the tester makes a request that exceeds the capabilities of the UUT. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 965 8.3.3.28 USB Type-C Referenced States This section contains states cross-referenced from the [USB Type-C 2.4] specification. 8.3.3.28.1 ErrorRecovery state The ErrorRecovery state is used to electronically disconnect Port Partners using the USB Type-C connector. The ErrorRecovery state Shall be entered when there are errors on USB Type-C Ports which cannot be recovered by Hard Reset. The ErrorRecovery state Shall map to USB Type-C ErrorRecovery state operation as defined in the [USB Type-C 2.4] specification. Bus powered Sinks Shall Not be required to meet this requirement as removal of their power will serve the same purpose. On entry to the ErrorRecovery state the Explicit Contract and PD Connection Shall be ended. On exit from the ErrorRecovery state a new Explicit Contract Should be established once the Port Partners have re-connected over the CC wire. Page 966 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.29 Policy Engine States Table 8.154, "Policy Engine States" lists the states used by the various state machines. Table 8.154 Policy Engine States State name Reference SenderResponseTimer SRT_Stopped Section 8.3.3.1.1.1 SRT_Running Section 8.3.3.1.1.2 SRT_Expired Section 8.3.3.1.1.3 Source Port PE_SRC_Startup Section 8.3.3.2.1 PE_SRC_Discovery Section 8.3.3.2.2 PE_SRC_Send_Capabilities Section 8.3.3.2.3 PE_SRC_Negotiate_Capability Section 8.3.3.2.4 PE_SRC_Transition_Supply Section 8.3.3.2.5 PE_SRC_Ready Section 8.3.3.2.6 PE_SRC_Disabled Section 8.3.3.2.7 PE_SRC_Capability_Response Section 8.3.3.2.8 PE_SRC_Hard_Reset Section 8.3.3.2.9 PE_SRC_Hard_Reset_Received Section 8.3.3.2.10 PE_SRC_Transition_to_default Section 8.3.3.2.11 PE_SRC_Give_Source_Cap Section 8.3.3.2.15 PE_SRC_Get_Sink_Cap Section 8.3.3.2.12 PE_SRC_Wait_New_Capabilities Section 8.3.3.2.13 PE_SRC_EPR_Keep_Alive Section 8.3.3.2.14 Sink Port PE_SNK_Startup Section 8.3.3.3.1 PE_SNK_Discovery Section 8.3.3.3.2 PE_SNK_Wait_for_Capabilities Section 8.3.3.3.3 PE_SNK_Evaluate_Capability Section 8.3.3.3.4 PE_SNK_Select_Capability Section 8.3.3.3.5 PE_SNK_Transition_Sink Section 8.3.3.3.6 PE_SNK_Ready Section 8.3.3.3.7 PE_SNK_Hard_Reset Section 8.3.3.3.8 PE_SNK_Transition_to_default Section 8.3.3.3.9 PE_SNK_Give_Sink_Cap Section 8.3.3.3.10 PE_SNK_Get_Source_Cap Section 8.3.3.3.12 PE_SNK_EPR_Keep_Alive Section 8.3.3.3.11 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 967 Soft Reset and Protocol Error Source Port Soft Reset PE_SRC_Send_Soft_Reset Section 8.3.3.4.1.1 PE_SRC_Soft_Reset Section 8.3.3.4.1.2 Sink Port Soft Reset PE_SNK_Send_Soft_Reset Section 8.3.3.4.2.1 PE_SNK_Soft_Reset Section 8.3.3.4.2.2 Data Reset DFP Data Reset PE_DDR_Send_Data_Reset Section 8.3.3.5.1.1 PE_DDR_Data_Reset_Received Section 8.3.3.5.1.2 PE_DDR_Wait_For_VCONN_Off Section 8.3.3.5.1.3 PE_DDR_Perform_Data_Reset Section 8.3.3.5.1.4 UFP Data Reset PE_UDR_Send_Data_Reset Section 8.3.3.5.2.1 PE_UDR_Data_Reset_Received Section 8.3.3.5.2.2 PE_UDR_Turn_Off_VCONN Section 8.3.3.5.2.3 PE_UDR_Send_Ps_Rdy Section 8.3.3.5.2.4 PE_UDR_Wait_For_Data_Reset_Complete Section 8.3.3.5.2.5 Not Supported Message Source Port Not Supported PE_SRC_Send_Not_Supported Section 8.3.3.6.1.1 PE_SRC_Not_Supported_Received Section 8.3.3.6.1.2 PE_SRC_Chunk_Received Section 8.3.3.6.1.3 Sink Port Not Supported PE_SNK_Send_Not_Supported Section 8.3.3.6.2.1 PE_SNK_Not_Supported_Received Section 8.3.3.6.2.2 PE_SNK_Chunk_Received Section 8.3.3.6.2.3 Source Alert Source Port Source Alert PE_SRC_Send_Source_Alert Section 8.3.3.7.1.1 PE_SRC_Wait_for_Get_Status Section 8.3.3.7.1.2 Sink Port Source Alert PE_SNK_Source_Alert_Received Section 8.3.3.7.2.1 Sink Port Sink Alert PE_SNK_Send_Sink_Alert Section 8.3.3.7.3.1 PE_SNK_Wait_for_Get_Status Section 8.3.3.7.3.2 Source Port Sink Alert PE_SRC_Sink_Alert_Received Section 8.3.3.7.4.1 Table 8.154 Policy Engine States State name Reference Page 968 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Source/Sink Extended Capabilities Sink Port Get Source Capabilities Extended PE_SNK_Get_Source_Cap_Ext Section 8.3.3.8.1.1 Source Port Give Source Capabilities Extended PE_SRC_Give_Source_Cap_Ext Section 8.3.3.8.2.1 Source Port Get Sink Capabilities Extended PE_SRC_Get_Sink_Cap_Ext Section 8.3.3.8.3.1 Source Port Give Source Capabilities Extended PE_SNK_Give_Sink_Cap_Ext Section 8.3.3.8.4.1 Source Information Sink Port Get Source Information PE_SNK_Get_Source_Info Section 8.3.3.9.1.1 Source Port Give Source Information PE_SRC_Give_Source_Info Section 8.3.3.9.2.1 Status Get Status PE_Get_Status Section 8.3.3.10.1.1 Give Status PE_Give_Status Section 8.3.3.10.1.1 Sink Port Get PPS Status PE_SNK_Get_PPS_Status Section 8.3.3.10.3.1 Source Port Give PPS Status PE_SRC_Give_PPS_Status Section 8.3.3.10.4.1 Battery Capabilities Get Battery Capabilities PE_Get_Battery_Cap Section 8.3.3.11.1.1 Give Battery Capabilities PE_Give_Battery_Cap Section 8.3.3.11.2.1 Battery Status Get Battery Status PE_Get_Battery_Status Section 8.3.3.12.1.1 Give Battery Status PE_Give_Battery_Status Section 8.3.3.12.2.1 Manufacturer Information Get Manufacturer Information PE_Get_Manufacturer_Info Section 8.3.3.13.1.1 Give Manufacturer Information PE_Give_Manufacturer_Info Section 8.3.3.13.2.1 Country Codes and Information Get Country Codes PE_Get_Country_Codes Section 8.3.3.14.1.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 969 Give Country Codes PE_Give_Country_Codes Section 8.3.3.14.2.1 Get Country Information PE_Get_Country_Info Section 8.3.3.14.3.1 Give Country Information PE_Give_Country_Info Section 8.3.3.14.4.1 Revision Get Revision PE_Get_Revision Section 8.3.3.15.1.1 Give Revision PE_Give_Revision Section 8.3.3.15.2.1 Enter USB DFP Enter USB PE_DEU_Send_Enter_USB Section 8.3.3.16.1.1 UFP Enter USB PE_UEU_Enter_USB_Received Section 8.3.3.16.2.1 Security Request/Response Send Security Request PE_Send_Security_Request Section 8.3.3.17.1.1 Send Security Response PE_Send_Security_Response Section 8.3.3.17.2.1 Security Response Received PE_Security_Response_Received Section 8.3.3.17.3.1 Firmware Update Request/Response Send Firmware Update Request PE_Send_Firmware_Update_Request Section 8.3.3.18.1.1 Send Firmware Update Response PE_Send_Firmware_Update_Response Section 8.3.3.18.2.1 Firmware Update Response Received PE_Firmware_Update_Response_Received Section 8.3.3.18.3.1 Dual-Role Port DFP to UFP Data Role Swap PE_DRS_DFP_UFP_Evaluate_Swap Section 8.3.3.19.1.2 PE_DRS_DFP_UFP_Accept_Swap Section 8.3.3.19.1.3 PE_DRS_DFP_UFP_Change_to_UFP Section 8.3.3.19.1.4 PE_DRS_DFP_UFP_Send_Swap Section 8.3.3.19.1.5 PE_DRS_DFP_UFP_Reject_Swap Section 8.3.3.19.1.6 Table 8.154 Policy Engine States State name Reference Page 970 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 UFP to DFP Data Role Swap PE_DRS_UFP_DFP_Evaluate_Swap Section 8.3.3.19.2.2 PE_DRS_UFP_DFP_Accept_Swap Section 8.3.3.19.2.3 PE_DRS_UFP_DFP_Change_to_DFP Section 8.3.3.19.2.4 PE_DRS_UFP_DFP_Send_Swap Section 8.3.3.19.2.5 PE_DRS_UFP_DFP_Reject_Swap Section 8.3.3.19.2.6 Source to Sink Power Role Swap PE_PRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.3.2 PE_PRS_SRC_SNK_Accept_Swap Section 8.3.3.19.3.3 PE_PRS_SRC_SNK_Transition_to_off Section 8.3.3.19.3.4 PE_PRS_SRC_SNK_Assert_Rd Section 8.3.3.19.3.5 PE_PRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.3.6 PE_PRS_SRC_SNK_Send_Swap Section 8.3.3.19.3.7 PE_PRS_SRC_SNK_Reject_Swap Section 8.3.3.19.3.8 Sink to Source Power Role Swap PE_PRS_SNK_SRC_Evaluate_Swap Section 8.3.3.19.4.2 PE_PRS_SNK_SRC_Accept_Swap Section 8.3.3.19.4.3 PE_PRS_SNK_SRC_Transition_to_off Section 8.3.3.19.4.4 PE_PRS_SNK_SRC_Assert_Rp Section 8.3.3.19.4.5 PE_PRS_SNK_SRC_Source_on Section 8.3.3.19.4.6 PE_PRS_SNK_SRC_Send_Swap Section 8.3.3.19.4.7 PE_PRS_SNK_SRC_Reject_Swap Section 8.3.3.19.4.8 Source to Sink Fast Role Swap PE_FRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.5.2 PE_FRS_SRC_SNK_Accept_Swap Section 8.3.3.19.5.3 PE_FRS_SRC_SNK_Transition_to_off Section 8.3.3.19.5.4 PE_FRS_SRC_SNK_Assert_Rd Section 8.3.3.19.5.5 PE_FRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.5.6 Sink to Source Fast Role Swap PE_FRS_SNK_SRC_Start_AMS Section 8.3.3.19.6.1 PE_FRS_SNK_SRC_Send_Swap Section 8.3.3.19.6.2 PE_FRS_SNK_SRC_Transition_to_off Section 8.3.3.19.6.3 PE_FRS_SNK_SRC_VBUS_Applied Section 8.3.3.19.6.4 PE_FRS_SNK_SRC_Assert_Rp Section 8.3.3.19.6.5 PE_FRS_SNK_SRC_Source_on Section 8.3.3.19.6.6 Dual-Role Source Port Get Source Capabilities PE_DR_SRC_Get_Source_Cap Section 8.3.3.19.7.1 Dual-Role Source Port Give Sink Capabilities PE_DR_SRC_Give_Sink_Cap Section 8.3.3.19.8.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 971 Dual-Role Sink Port Get Sink Capabilities PE_DR_SNK_Get_Sink_Cap Section 8.3.3.19.9.1 Dual-Role Sink Port Give Source Capabilities PE_DR_SNK_Give_Source_Cap Section 8.3.3.19.10.1 Dual-Role Source Port Get Source Capabilities Extended PE_DR_SRC_Get_Source_Cap_Ext Section 8.3.3.19.11.1 Dual-Role Sink Port Give Source Capabilities Extended PE_DR_SNK_Give_Source_Cap_Ext Section 8.3.3.19.12.1 Dual-Role Sink Port Get Sink Capabilities Extended PE_DR_SNK_Get_Sink_Cap_Ext Section 8.3.3.19.13.1 Dual-Role Source Port Give Sink Capabilities Extended PE_DR_SRC_Give_Sink_Cap_Ext Section 8.3.3.19.14.1 Dual-Role Source Port Get Source Information PE_DR_SRC_Get_Source_Info Section 8.3.3.19.15.1 Dual-Role Sink Port Give Source Information PE_DR_SNK_Give_Source_Info Section 8.3.3.19.16.1 USB Type-C VCONN Swap PE_VCS_Send_Swap Section 8.3.3.20.1 PE_VCS_Evaluate_Swap Section 8.3.3.20.2 PE_VCS_Accept_Swap Section 8.3.3.20.3 PE_VCS_Reject_Swap Section 8.3.3.20.4 PE_VCS_Wait_For_VCONN Section 8.3.3.20.5 PE_VCS_Turn_Off_VCONN Section 8.3.3.20.6 PE_VCS_Turn_On_VCONN Section 8.3.3.20.7 PE_VCS_Send_Ps_Rdy Section 8.3.3.20.8 PE_VCS_Force_VCONN Section 8.3.3.20.9 Initiator Structured VDM Initiator to Port Structured VDM Discover Identity PE_INIT_PORT_VDM_Identity_Request Section 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_ACKed Section 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_NAKed Section 8.3.3.21.1.3 Initiator Structured VDM Discover SVIDs PE_INIT_VDM_SVIDs_Request Section 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_ACKed Section 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_NAKed Section 8.3.3.21.2.3 Initiator Structured VDM Discover Modes PE_INIT_VDM_Modes_Request Section 8.3.3.21.3.1 PE_INIT_VDM_Modes_ACKed Section 8.3.3.21.3.2 PE_INIT_VDM_Modes_NAKed Section 8.3.3.21.3.3 Table 8.154 Policy Engine States State name Reference Page 972 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Initiator Structured VDM Attention PE_INIT_VDM_Attention_Request Section 8.3.3.21.4.1 Responder Structured VDM Responder Structured VDM Discovery Identity PE_RESP_VDM_Get_Identity Section 8.3.3.22.1.1 PE_RESP_VDM_Send_Identity Section 8.3.3.22.1.2 PE_RESP_VDM_Get_Identity_NAK Section 8.3.3.22.1.3 Responder Structured VDM Discovery SVIDs PE_RESP_VDM_Get_SVIDs Section 8.3.3.22.2.1 PE_RESP_VDM_Send_SVIDs Section 8.3.3.22.2.2 PE_RESP_VDM_Get_SVIDs_NAK Section 8.3.3.22.2.3 Responder Structured VDM Discovery Modes PE_RESP_VDM_Get_Modes Section 8.3.3.22.3.1 PE_RESP_VDM_Send_Modes Section 8.3.3.22.3.2 PE_RESP_VDM_Get_Modes_NAK Section 8.3.3.22.3.3 Receiving a Structured VDM Attention PE_RCV_VDM_Attention_Request Section 8.3.3.22.4.1 DFP Structured VDM DFP Structured VDM Mode Entry PE_DFP_VDM_Mode_Entry_Request Section 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_ACKed Section 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_NAKed Section 8.3.3.23.1.3 DFP Structured VDM Mode Exit PE_DFP_VDM_Mode_Exit_Request Section 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_ACKed Section 8.3.3.23.2.2 UFP Structure VDM UFP Structured VDM Enter Mode PE_UFP_VDM_Evaluate_Mode_Entry Section 8.3.3.24.1.1 PE_UFP_VDM_Mode_Entry_ACK Section 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_NAK Section 8.3.3.24.1.3 UFP Structured VDM Exit Mode PE_UFP_VDM_Mode_Exit Section 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit_ACK Section 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_NAK Section 8.3.3.24.2.3 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 973 Cable Plug Specific Cable Ready PE_CBL_Ready Section 8.3.3.25.1.1 Mode Entry PE_CBL_Evaluate_Mode_Entry Section 8.3.3.25.4.1.1 PE_CBL_Mode_Entry_ACK Section 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_NAK Section 8.3.3.25.4.1.3 Mode Exit PE_CBL_Mode_Exit Section 8.3.3.25.4.2.1 PE_CBL_Mode_Exit_ACK Section 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_NAK Section 8.3.3.25.4.1.3 Cable Soft Reset PE_CBL_Soft_Reset Section 8.3.3.25.2.1.1 Cable Hard Reset PE_CBL_Hard_Reset Section 8.3.3.25.2.2.1 DFP/VCONN Source Soft Reset or Cable Reset PE_DFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Cable_Reset Section 8.3.3.25.2.3.2 UFP/VCONN Source Soft Reset or Cable Reset PE_UFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.4.1 Source Startup Structured VDM Discover Identity PE_SRC_VDM_Identity_Request Section 8.3.3.25.3.1 PE_SRC_VDM_Identity_ACKed Section 8.3.3.25.3.2 PE_SRC_VDM_Identity_NAKed Section 8.3.3.25.3.3 EPR Mode Source EPR Mode Entry PE_SRC_Evaluate_EPR_Mode_Entry Section 8.3.3.26.1.1 PE_SRC_EPR_Mode_Entry_Ack Section 8.3.3.26.1.2 PE_SRC_EPR_Mode_Discover_Cable Section 8.3.3.26.1.3 PE_SRC_EPR_Mode_Evaluate_Cable_EPR Section 8.3.3.26.1.4 PE_SRC_EPR_Mode_Entry_Succeeded Section 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Failed Section 8.3.3.26.1.6 Sink EPR Mode Entry PE_SNK_Send_EPR_Mode_Entry Section 8.3.3.26.2.1 PE_SNK_EPR_Mode_Wait_For_Response Section 8.3.3.26.2.2 Source EPR Mode Exit PE_SRC_Send_EPR_Mode_Exit Section 8.3.3.26.3.1 PE_SRC_EPR_Mode_Exit_Received Section 8.3.3.26.3.2 Table 8.154 Policy Engine States State name Reference Page 974 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Sink EPR Mode Exit PE_SNK_Send_EPR_Mode_Exit Section 8.3.3.26.4.1 PE_SNK_EPR_Mode_Exit_Received Section 8.3.3.26.4.2 BIST BIST Carrier Mode PE_BIST_Carrier_Mode Section 8.3.3.27.1.1 BIST Carrier Mode PE_BIST_Test_Mode Section 8.3.3.27.2.1 BIST Shared Capacity Test Mode PE_BIST_Shared_Capacity_Test_Mode Section 8.3.3.27.3.1 USB Type-C referenced states ErrorRecovery Section 8.3.3.28.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 975 9 States and Status Reporting 9.1 Overview This chapter describes the Status reporting mechanisms for devices with data connections (e.g., D+/D- and or SSTx+/- and SSRx+/-). It also describes the corresponding USB state a device that supports USB PD Shall transition to as a result of changes to the USB PD state that the device is in. This chapter does not define the System Policy or the System Policy Manager. That is defined in [UCSI]. In addition, the Policies themselves are not described here; these are left to the implementers of the relevant products and systems to define. All PD Capable USB (PDUSB) Devices Shall report themselves as self-powered devices (over USB) when plugged into a PD capable Port even if they are entirely powered from VBUS. However, there are some differences between PD and [USB 2.0] / [USB 3.2]; for example, the presence of VBUS alone does not mean that the device (Consumer) moves from the USB Attached State to the USB Powered State. Similarly, the removal of VBUS alone does not move the device (Consumer) from any of the USB states to the USB Attached State. See Section 9.1.2, "Mapping to USB Device States" for details. PDUSB Devices Shall follow the PD requirements when it comes to suspend (see Section 6.4.1.2.1.2, "USB Suspend Supported"), configured, and operational power. The PD requirements when the device is configured or operational are defined in this section (see Table 9.4, "PD Consumer Port Descriptor"). Note: The power requirements reported in the PD Consumer Port descriptor of the device Shall override the power draw reported in the bMaxPower field in the configuration descriptor. A PDUSB Device Shall report zero in the bMaxPower field after successfully negotiating a mutually agreeable Explicit Contract and Shall disconnect and re-enumerate when it switches operation back to operating in standard [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. When operating in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] mode it Shall report its power draw via the bMaxPower field. Each Provider and Consumer will have their own Local Policies which operate between Port Partners. An example of a typical PD system is shown in Figure 9.1, "Example PD Topology". This example consists of a Provider, Consumer/Providers and Consumers connected together in a tree topology. Between directly connected devices there is both a flow of Power and also Communication consisting of both Status and Control information. Page 976 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.1 Example PD Topology Consumer Consumer Consumer/ Provider Consumer/ Provider Provider AC/Battery AC/Battery Power PD Communication P/C P/C P/C P/C Provider/Consumer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 977 Figure 9.2, "Mapping of PD Topology to USB" shows how this same topology can be mapped to USB. Figure 9.2 Mapping of PD Topology to USB Device Device Device Root Hub AC/Battery AC/Battery Power PD Communication Hub Page 978 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 In a USB based system, policy is managed by the host and communication of system level policy information is via standard USB data line communication. This is a separate mechanism to the USB Power Delivery VBUS protocol which is used to manage Local Policy. When USB Communication is used, status information and control requests are passed directly between the System Policy Manager (SPM) on the host and the Provider or Consumer. See Figure 9.3, "Use of SPM in the PD System". Figure 9.3 Use of SPM in the PD System Status information comes from a Provider or Consumer to the SPM so it can better manage the resources on the host and provide feedback to the end user. Real systems will be a mixture of devices which in terms of power management support might have implemented PD, [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] or they might even just be non-compliant “power sucking devices”. The level of communication of system status to the SPM will therefore not necessarily be comprehensive. The aim of the status mechanisms described here is to provide a mechanism whereby each connected entity in the system provides as much information as possible on the status of itself. Information described in this section that is communicated to the SPM is as follows:  Versions of USB Type-C®, PD and BC supported.  Capabilities as a Provider/Consumer.  Current operational state of each Port e.g. Standard, USB Type-C Current, BC, PD and Negotiated power level.  Status of AC or Battery Power for each PDUSB Device in the system. The SPM can Negotiate with Providers or Consumers in the system in order to request a different Local Policy, or to request the amount of power to be delivered by the Provider to the Consumer. Any change in Local Policy could Device Device Device Host (SPM) AC/Battery AC/Battery Power PD Communication USB Communication Hub Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 979 trigger a Re-negotiation of the Explicit Contract, using USB Power Delivery protocols, between a directly connected Provider and Consumer. A change in how much power is available can, for example, cause a Re-negotiation. 9.1.1 PDUSB Device and Hub Requirements All PDUSB Devices Shall return all relevant descriptors mentioned in this chapter. PDUSB Hubs Shall also support a PD bridge as defined in [UCSI]. Page 980 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.2 Mapping to USB Device States As mentioned in Section 9.1, "Overview" a PDUSB Device reports itself as a self-powered device. However, the device Shall determine whether or not it is in the USB Attached State or USB Powered States as described in Figure 9.4, "USB Attached to USB Powered State Transition", Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" and Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" All other USB states of the PDUSB Device Shall be as described in Chapter 9 of [USB 2.0] and [USB 3.2]. Figure 9.4, "USB Attached to USB Powered State Transition" shows how a PDUSB Device determines when to transition from the USB Attached State to the USB Powered State. USB Type-C Dead Battery operation does not require special handling since the default state at Attach or after a Hard Reset is that the USB Device is a Sink. Figure 9.4 USB Attached to USB Powered State Transition Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Consumer. A PDUSB Device determines that it is performing a Power Role Swap as described in Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present No Yes Can enumerate? Yes Device is a Source? Attached Sink? USB Attached Yes Device in Sink Mode No Negotiate enough Power? No USB Powered No No Yes Device in Source Mode (5V) Yes Hard Reset Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 981 Figure 9.5 Any USB State to USB Attached State Transition (When operating as a Consumer) Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Provider. Figure 9.6 Any USB State to USB Attached State Transition (When operating as a Provider) Figure 9.7, "Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap)" shows how a PDUSB Device using the USB Type-C connector determines when to transition from the USB Powered State to the USB Attached State after a Data Role Swap has been performed i.e., it has just changed from operation as a PDUSB Host to operation as a PDUSB Device. The Data Role Swap is described in Section 6.3.9, "DR_Swap Message". A Hard Reset will also return a Sink acting as a PDUSB Host to PDUSB Device operation as described in Section 6.8.3, "Hard Reset". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present Yes No Swapping Power Roles? Any USB State USB Attached Yes No Hard Reset and Can Operate Hard Reset and Can’t Operate Hard Reset and Bus Powered Lack of PD comms? No Yes Any USB State USB Attached Local Power Source Lost Hard Reset Page 982 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.7 Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap) VBUS Present Yes Swapping Data Roles? Any USB State USB Attached No Yes Hard Reset Changes Data Role Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 983 9.1.3 PD Software Stack Figure 9.8, "Software stack on a PD aware OS" gives an example of the software stack on a PD aware OS. In this stack we are using the example of a system with an xHCI based controller. The USB Power Delivery hardware May or May Not be a part of the xHC. Figure 9.8 Software stack on a PD aware OS Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager Page 984 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.4 PDUSB Device Enumeration As described earlier, a PDUSB Device acts as a self-powered device with some caveats with respect to how it transitions from the USB Attached State to USB Powered State. Figure 9.9, "Enumeration of a PDUSB Device" gives a high-level overview of the enumeration steps involved due to this change. A PDUSB Device will first (Step1) interact with the Power Delivery hardware and the Local Policy manager to determine whether or not it can get sufficient power to enumerate/operate. PD is likely to have established a Explicit Contract prior to enumeration. The SPM will be notified (Step 2) of the result of this Negotiation between the Power Delivery hardware and the PDUSB Device. After successfully negotiating a mutually agreeable Explicit Contract the device will signal a connect to the xHC. The standard USB enumeration process (Steps 3, 4 and 5) is then followed to load the appropriate driver for the function(s) that the PDUSB Device exposes. Figure 9.9 Enumeration of a PDUSB Device If a PDUSB Device cannot perform its intended function with the amount of power that it can get from the Port it is connected to, then the host system Should display a notification (on a PD aware OS) about the failure to provide sufficient power to the device. In addition, the device Shall follow the requirements listed in Section 8.2.5.2.1, "Local device handling of mismatch". Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager 5 4 3 2 1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 985 9.2 PD Specific Descriptors A PDUSB Device Shall return all relevant descriptors mentioned in this section. The device Shall return its capability descriptors as part of the device's Binary Object Store (BOS) descriptor set. Table 9.1, "USB Power Delivery Type Codes" lists the type of PD device capabilities. Table 9.1 USB Power Delivery Type Codes Capability Code Value Description POWER_DELIVERY_CAPABILITY 06H Defines the various PD Capabilities of this device BATTERY_INFO_CAPABILITY 07H Provides information on each Battery supported by the device PD_CONSUMER_PORT_CAPABILITY 08H The Consumer characteristics of a Port on the device PD_PROVIDER_PORT_CAPABILITY 09H The Provider characteristics of a Port on the device Page 986 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.1 USB Power Delivery Capability Descriptor Table 9.2, "USB Power Delivery Capability Descriptor" details the fields in the USB POWER_DELIVERY_CAPABILITY Descriptor. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: POWER_DELIVERY_CAPABILITY 3 bReserved 1 Reserved Shall be set to zero. 4 bmAttributes 4 Bitmap Bitmap encoding of supported device level features. A value of one in a bit location indicates a feature is supported; a value of zero indicates it is not supported. Encodings are: Bit Description 0 Reserved. Shall be set to zero. 1 Battery Charging. This bit Shall be set to one to indicate this device supports [USBBC 1.2] as per the value reported in the bcdBCVersion field. 2 USB Power Delivery. This bit Shall be set to one to indicate this device supports the USB Power Delivery Specification as per the value reported in the bcdPDVersion field. 3 Provider. This bit Shall be set to one to indicate this device is capable of providing power. This field is only Valid if Bit 2 is set to one. 4 Consumer. This bit Shall be set to one to indicate that this device is a consumer of power. This field is only Valid if Bit 2 is set to one. 5 This bit Shall be set to 1 to indicate that this device supports the feature CHARGING_POLICY. Note: Supporting the CHARGING_POLICY feature does not require a BC or PD mechanism to be implemented. 6 USB Type-C Current. This bit Shall be set to one to indicate this device supports power capabilities defined in[USB Type-C 2.4] as per the value reported in the bcdUSBTypeCVersion field 7 Reserved. Shall be set to zero. 15:8 bmPowerSource. At least one of the following bits 8, 9 and 14 Shall be set to indicate which power sources are supported. Bit Description 8 AC Supply 9 Battery 10 Other 13:11 NumBatteries. This field Shall only be Valid when the Battery field is set to one and Shall be used to report the number of batteries in the device. 14 Uses VBUS 15 Reserved and Shall be set to zero. 13:16 Reserved. Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 987 9.2.2 Battery Info Capability Descriptor A PDUSB Device Shall support the capability descriptor shown in Table 9.3, "Battery Info Capability Descriptor" if it reported that one of its power sources was a Battery in the bmPowerSource field in its Power Deliver Capability Descriptor. It Shall return one BATTERY_INFO_CAPABILITY Descriptor per Battery it supports. 8 bcdBCVersion 2 BCD Battery Charging Specification Release Number in Binary-Coded Decimal (e.g., V1.20 is 120H). This field Shall only be Valid if the device indicates that it supports [USBBC 1.2] in the bmAttributes field. 10 bcdPDVersion 2 BCD USB Power Delivery Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports PD in the bmAttributes field. 12 bcdUSBTypeCVersion 2 BCD USB Type-C Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports USB Type-C in the bmAttributes field. Table 9.3 Battery Info Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: BATTERY_INFO_CAPABILITY 3 iBattery 1 Index Index of string descriptor Shall contain the user-friendly name for this Battery. 4 iSerial 1 Index Index of string descriptor Shall contain the Serial Number String for this Battery. 5 iManufacturer 1 Index Index of string descriptor Shall contain the name of the Manufacturer for this Battery. 6 bBatteryId 1 Number Value Shall be used to uniquely identify this Battery in status Messages. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 dwChargedThreshold 4 mWh Shall contain the Battery charge value above which this Battery is considered to be fully charged but not necessarily “topped off.” 12 dwWeakThreshold 4 mWh Shall contain the minimum charge level of this Battery such that above this threshold, a device can be assured of being able to power up successfully (see [USBBC 1.2]). 16 dwBatteryDesignCapacity 4 mWh Shall contain the design capacity of the Battery. 20 dwBatteryLastFullchargeCapacity 4 mWh Shall contain the maximum capacity of the Battery when fully charged. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description Page 988 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.3 PD Consumer Port Capability Descriptor A PDUSB Device Shall support the PD_CONSUMER_PORT_CAPABILITY descriptor shown in Table 9.4, "PD Consumer Port Descriptor" if it is a Consumer. Table 9.4 PD Consumer Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_CONSUMER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Consumer Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 wMinVoltage 2 Number Shall contain the minimum voltage in 50mV units that this Consumer is capable of operating at. 8 wMaxVoltage 2 Number Shall contain the maximum voltage in 50mV units that this Consumer is capable of operating at. 10 wReserved 2 Number Reserved and Shall be set to zero. 12 dwMaxOperatingPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw when it is in a steady state operating mode. 16 dwMaxPeakPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw for a short duration of time (dwMaxPeakPowerTime) before it falls back into a steady state. 20 dwMaxPeakPowerTime 4 Number Shall contain the time in 100ms units that this Consumer can draw peak current. A device Shall set this field to 0xFFFF if this value is unknown. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 989 9.2.4 PD Provider Port Capability Descriptor A PDUSB Device Shall support the PD_PROVIDER_PORT_CAPABILITY descriptor shown in Table 9.5, "PD Provider Port Descriptor" if it is a Provider. Table 9.5 PD Provider Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_PROVIDER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Provider Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 bNumOfPDObjects 1 Number Shall indicate the number of Power Data Objects. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 wPowerDataObject1 4 Bitmap Shall contain the first Power Data Object supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. ... ... ... ... ... 4*(N+1) wPowerDataObjectN 4 Bitmap Shall contain the 2nd and subsequent Power Data Objects supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. Page 990 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.3 PD Specific Requests and Events A PDUSB Device that is compliant to this specification Shall support the Battery related requests if it has a Battery. A PDUSB Hub that is compliant to this specification Shall support a USB PD Bridge as described in [UCSI] irrespective of whether the PDUSB Hub is a Provider, a Consumer, or both. 9.3.1 PD Specific Requests PD defines requests to which PDUSB Devices Shall respond as outlined in Table 9.6, "PD Requests". All Valid requests in Table 9.6, "PD Requests" Shall be implemented by PDUSB Devices. Table 9.7, "PD Request Codes" gives the bRequest values for Commands that are not listed in the hub/device framework chapters of [USB 2.0], [USB 3.2]. Table 9.8, "PD Feature Selectors" gives the Valid feature selectors for the PD class. Refer to Section 9.4.2.1, "BATTERY_WAKE_MASK Feature Selector", and Section 9.4.2.2, "CHARGING_POLICY Feature Selector" for a description of the features. Table 9.6 PD Requests Request bmRequestType bRequest wValue wIndex wLength Data GetBatteryStatus 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status SetPDFeature 00000000B set_feature Feature Selector Feature Specific Zero None Table 9.7 PD Request Codes bRequest Value GET_BATTERY_STATUS 21 Table 9.8 PD Feature Selectors Feature Selector Recipient Value BATTERY_WAKE_MASK Device 40 CHARGING_POLICY Device 54 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 991 9.4 PDUSB Hub and PDUSB Peripheral Device Requests 9.4.1 GetBatteryStatus The request shown in Table 9.9, "Get Battery Status Request" returns the current status of the Battery in a PDUSB Hub/Peripheral, with Battery Status information as shown in Table 9.10, "Battery Status Structure". Table 9.9 Get Battery Status Request bmRequestType bRequest wValue wIndex wLength Data 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status Table 9.10 Battery Status Structure Offset Field Size Value Description 0 bBatteryAttributes 1 Number Shall indicate whether a Battery is installed and whether this is charging or discharging. Value Description 0 There is no Battery 1 The Battery is charging 2 The Battery is discharging 3 The Battery is neither discharging nor charging 255...4 Reserved and Shall Not be used 1 bBatterySOC 1 Number Shall indicate the Battery State of Charge given as percentage value from Battery Remaining Capacity. 2 bBatteryStatus 1 Number If a Battery is present Shall indicate the present status of the Battery. Value Description 0 No error 1 Battery required and not present 2 Battery non-chargeable/wrong chemistry 3 Over-temp shutdown 4 Over-voltage shutdown 5 Over-current shutdown 6 Fatigued Battery 7 Unspecified error 255...8 Reserved and Shall Not be used Page 992 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 If wValue or wLength are not as specified above, then the behavior of the PDUSB Device is not specified. If wIndex refers to a Battery that does not exist, then the PDUSB Device Shall respond with a Request Error. If the PDUSB Device is not configured, the PDUSB Hub's response to this request is undefined. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. 9.4.2 SetPDFeature The request shown in Table 9.11, "Set PD Feature" sets the value requested in the PDUSB Hub/Peripheral. Setting a feature enables that feature or starts a process associated with that feature; see Table 9.8, "PD Feature Selectors" for the feature selector definitions. Features that May be set with this request are:  BATTERY_WAKE_MASK.  CHARGING_POLICY. 3 bRemoteWakeCapStatus 1 Bitmap If the device supports remote wake, then the device Shall support Battery Remote wake events. The default value for the Remote wake events Shall be turned off (set to zero) and can be enable/disabled by the host as required. If set to one the device Shall generate a wake event when a change of status occurs. See Section 9.4.2, "SetPDFeature" for more details. Value Description 0 Battery present event 1 Charging flow 2 Battery error 7:3 Reserved and Shall be set to zero 4 wRemainingOperatingTime 2 Number Shall contain the operating time (in minutes) until the Weak Battery threshold is reached, based on Present Battery Strength and the device's present operational power needs. Note: This value Shall exclude any additional power re- ceived from charging. A Battery that is not capable of returning this information Shall return a value of 0xFFFF. 6 wRemainingChargeTime 2 Number Shall contain the remaining time (in minutes) until the Charged Battery threshold is reached based on Present Battery Strength, charging power and the device's present operational power needs. Value Shall only be Valid if the Charging Flow is "Charging". A Battery that is not capable of returning this information Shall return a value of 0xFFFF. Table 9.11 Set PD Feature bmRequestType bRequest wValue wIndex wLength Data 00000000B set_ feature Feature Selector Feature Specific Zero None Table 9.10 Battery Status Structure Offset Field Size Value Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 993 9.4.2.1 BATTERY_WAKE_MASK Feature Selector When the feature selector is set to BATTERY_WAKE_MASK, then the wIndex field is structured as shown in Table 9.12, "Battery Wake Mask". The SPM May Enable or Disable the wake events associated with one or more of the above events by using this feature. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. Table 9.12 Battery Wake Mask Bit Description 0 Battery Present: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery has been inserted. 1 Charging Flow: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery switched from charging to discharging or vice versa. 2 Battery Error: When this bit is set then the PDUSB Device Shall generate a wake event if the Battery has detected an error condition. 15:3 Reserved and Shall Not be used Page 994 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.4.2.2 CHARGING_POLICY Feature Selector When the feature selector is set to CHARGING_POLICY, the wIndex field Shall be set to one of the values defined in Table 9.13, "Charging Policy Encoding". If the device is using USB Type-C Current above the default value or is using PD then this feature setting has no effect and the rules for power levels specified in the [USB Type-C 2.4] or USB PD specifications Shall apply. This is a Valid Command for the PDUSB Hub/Peripheral in the Address or Configured USB states. Further, it is only Valid if the device reports a USB PD capability descriptor in its BOS descriptor and Bit 5 of the bmAttributes in that descriptor is set to 1. The device will go back to the wIndex default value of 0 whenever it is reset. Table 9.13 Charging Policy Encoding Value Description 00H The device Shall follow the default current limits as defined in the USB 2.0 or USB 3.1 specification, or as negotiated through other USB mechanisms such as BC. This is the default value. 01H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCHPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 02H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCLPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 03H The device Shall Not consume any current for charging the device itself regardless of its USB state. 04H-FFFFH Reserved and Shall Not be used
10.1 - Introduction.................................................................................................................................. (Page 995)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 995 10 Power Rules 10.1 Introduction The flexibility of power provision on USB Type-C® is expected to lead to power adapter re-use and the increasingly widespread provision of USB power outlets in domestic and public places and in transport of all kinds. Environmental considerations could result in unbundled power adapters. Rules are needed to avoid incompatibility between the Sources and the Sinks they are used to power, in order to avoid user confusion and to meet user expectations. This section specifies a set of rules that Sources and Sinks Shall follow. These rules provide a simple and consistent user experience. The PDP Rating is a manufacturer declared value placed on packaging to help the user understand the capabilities of a Charger or the size of Charger required to power their device. For PDP values of 10W and above the PDP Shall be declared as an integer number of Watts. For PDP values less than 10W, the PDP Shall be declared in increments of 0.5W. The Source Power Rules define a PDP to provide a simple way to tell the user about the capabilities of their power adapter or device. PDP Rating is akin to the wattage rating of a light bulb - bigger numbers mean more capability. The Sink Power Rules define a PDP to provide a simple way to tell the user which Sources will provide adequate power for their Sink. 10.2 Source Power Rules The Source Power Rules defined in this section include both Normative and Optional rules. For all of the defined rules, the capabilities a Source exposes are based on the Port Maximum PDP, or if power constrained, the Port Present PDP of the Port. For a Guaranteed Capability Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Maximum PDP and Mode of operation (i.e., SPR Mode or EPR Mode). For a Managed Capability Port, except before the First Explicit Contract or before the Explicit Contract after the Port Present PDP changes on a Shared Capacity Charger Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Present PDP and Mode of operation (i.e., SPR Mode or EPR Mode). After the First Explicit Contract, this requirement assures that the attached Sink will always know what voltages (or voltage modes) are presently available from the Source. In order to meet the expectations of the user, the Maximum Current/Power in the Source Capabilities PDO or APDO for Sources with a PDP Rating of x Watts Shall be as follows:  Maximum current for Normative and Optional Fixed Supply/Variable Supply PDOs Shall be either RoundUp(x/voltage) or RoundDown(x/voltage) to the nearest 10mA.  Maximum current for SPR Programmable Power Supply APDOs Shall be as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". Note: When the Constant Power bit is set in the APDO, the programmable power supply's output current is as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" however the programmable power supply will limit its output current so that the product of its actual output voltage times the output current does not exceed the PDP.  If a 9V Prog, 15V Prog or 20V Prog Programmable Power Supply APDO is Advertised when not required by Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP", then the maximum current Shall be RoundDown (x/Prog Voltage) to the nearest 50mA. When the PPS Power Limited bit is clear the Source Shall provide this current at Maximum Voltage.  Maximum power for Optional Battery Supply PDOs Shall be ≤ x.
10.2 - Source Power Rules................................................................................................................... (Page 995)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 995 10 Power Rules 10.1 Introduction The flexibility of power provision on USB Type-C® is expected to lead to power adapter re-use and the increasingly widespread provision of USB power outlets in domestic and public places and in transport of all kinds. Environmental considerations could result in unbundled power adapters. Rules are needed to avoid incompatibility between the Sources and the Sinks they are used to power, in order to avoid user confusion and to meet user expectations. This section specifies a set of rules that Sources and Sinks Shall follow. These rules provide a simple and consistent user experience. The PDP Rating is a manufacturer declared value placed on packaging to help the user understand the capabilities of a Charger or the size of Charger required to power their device. For PDP values of 10W and above the PDP Shall be declared as an integer number of Watts. For PDP values less than 10W, the PDP Shall be declared in increments of 0.5W. The Source Power Rules define a PDP to provide a simple way to tell the user about the capabilities of their power adapter or device. PDP Rating is akin to the wattage rating of a light bulb - bigger numbers mean more capability. The Sink Power Rules define a PDP to provide a simple way to tell the user which Sources will provide adequate power for their Sink. 10.2 Source Power Rules The Source Power Rules defined in this section include both Normative and Optional rules. For all of the defined rules, the capabilities a Source exposes are based on the Port Maximum PDP, or if power constrained, the Port Present PDP of the Port. For a Guaranteed Capability Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Maximum PDP and Mode of operation (i.e., SPR Mode or EPR Mode). For a Managed Capability Port, except before the First Explicit Contract or before the Explicit Contract after the Port Present PDP changes on a Shared Capacity Charger Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Present PDP and Mode of operation (i.e., SPR Mode or EPR Mode). After the First Explicit Contract, this requirement assures that the attached Sink will always know what voltages (or voltage modes) are presently available from the Source. In order to meet the expectations of the user, the Maximum Current/Power in the Source Capabilities PDO or APDO for Sources with a PDP Rating of x Watts Shall be as follows:  Maximum current for Normative and Optional Fixed Supply/Variable Supply PDOs Shall be either RoundUp(x/voltage) or RoundDown(x/voltage) to the nearest 10mA.  Maximum current for SPR Programmable Power Supply APDOs Shall be as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". Note: When the Constant Power bit is set in the APDO, the programmable power supply's output current is as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" however the programmable power supply will limit its output current so that the product of its actual output voltage times the output current does not exceed the PDP.  If a 9V Prog, 15V Prog or 20V Prog Programmable Power Supply APDO is Advertised when not required by Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP", then the maximum current Shall be RoundDown (x/Prog Voltage) to the nearest 50mA. When the PPS Power Limited bit is clear the Source Shall provide this current at Maximum Voltage.  Maximum power for Optional Battery Supply PDOs Shall be ≤ x. Page 996 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.1 Source Power Rule Considerations The Source Power Rules are designed to:  Ensure the PDP Rating (PDP) of an adapter specified in watts explicitly defines the voltages and currents at each voltage the adapter supports.  Ensure that adapters with a large PDP Ratings are always capable of providing the power to devices designed for use with adapters with a smaller PDP Rating.  Enable an ecosystem of adapters that are inter-operable with the devices in the ecosystem. The considerations that lead to the Source Power Rules are based are summarized in Table 10.1, "Considerations for Sources". Table 10.1 Considerations for Sources Considerations Rationale Consequence Simple to identify capability A user going into an electronics retailer knows what they need Cannot have a complex identification scheme Higher power Sources are a superset of smaller ones Bigger is always better in user’s eyes – don’t want a degradation in performance Higher power Sources do everything smaller ones do Unambiguous Source definitions Sources with the same power rating but different VI combinations might not inter- operate To avoid user confusion, any given power rating has a single definition A range of power ratings Users and companies will want freedom to pick appropriate Source ratings Fixed profiles at specific power levels don’t provide adequate flexibility, e.g., profiles as defined in previous versions of PD. 5V@3A USB Type-C Source is defined by [USB Type-C 2.4] 5V@3A USB Type-C Source is considered All > 15W adapters must support 5V@3A or superset consideration is violated Maximize 3A cable utilization 3A cables will be ubiquitous Increase to maximum voltage (20V) before increasing current beyond 3A Optimize voltage rail count More rails are a higher burden for Sources, particularly in terms of testing 5V is a basic USB requirement. 48V provides the maximum capability. Some Sources are not able to provide significant power Some small Battery-operated Sources e.g., mobile devices, are able to provide more power directly from their Battery than from a regulated 5V supply In addition to the minimal 5V Advertisements are able to Advertise more power from their Battery Some Sources share power between multiple Ports (Hubs and multi-Port Chargers) Hubs and multi-port Chargers have to be supported See Section 10.3, "Sink Power Rules" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 997 10.2.2 Normative Voltages and Currents The voltages and currents an SPR Source with a PDP Rating of x Watts Shall support are as defined in Table 10.2, "SPR Normative Voltages and Minimum Currents". Table 10.2 SPR Normative Voltages and Minimum Currents Port Maximum PDP Rating (W) 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS 0.5 ≤ x ≤ 15 (PDP/5)A3 - - - - 15 < x ≤ 27 3A2 (PDP/9)A3 - - - 27 < x ≤ 45 3A2 3A2 (PDP/15)A3 - (9V – 15V):  (15V Fixed Supply Max Current) A 45 < x ≤ 60 3A2 3A2 3A2 (PDP/20)A3 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A 60 < x ≤ 100 3A2 3A2 3A2 (PDP/20)A1, 3 (9V – 15V):  (15V Fixed Supply Max Current) A4, 5 (15V – 20V):  (20V Fixed Supply Max Current) A1, 5 1) Requires a 5A cable. 2) The Fixed Supply PDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. Requires a 5A cable if over 3A is Advertised. 3) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 4) SPR AVS current for this voltage range is the maximum current as Advertised by the 15V Fixed Supply PDO. This current can be higher than 3A (refer to Note 2). Requires a 5A cable if over 3A is Advertised. 5) The Sink is allowed to request up to the 20V Fixed Supply Max Current when the requested voltage is 15.0V. Page 998 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SPR Managed Capability Ports when power constrained are defined to offer Valid (A)PDOs based on the port's Port Maximum PDP (as per Table 10.2, "SPR Normative Voltages and Minimum Currents") at lower Port Present PDP (as per Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP") because these voltages would otherwise be available if the Managed Capability Port power hadn't been constrained. Table 10.3 SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP Port Present PDP (W) 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS with Max Voltage of 15V or 20V per Table 10.26 5 < x ≤ 15 (PDP/5)A3 (PDP/9)A3,7, 8 (PDP/15)A3,7,8 (PDP/20)A3,7,8 (9V – 15V):  (15V Fixed Supply Max Current) A4, 6, 8 (15V – 20V):  (20V Fixed Supply Max Current) A6,8 15 < x ≤ 27 3A2 (PDP/9)A3 (PDP/15)A3,7 (PDP/20)A3,7 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A6 27 < x ≤ 45 3A2 3A2 (PDP/15)A3 45 < x ≤ 60 3A2 3A2 3A2 (PDP/20)A3 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A 60 < x ≤ 100 3A2 3A2 3A2 (PDP/20)A1, 3 (9V – 15V):  (15V Fixed Supply Max Current) A4, 5 (15V – 20V):  (20V Fixed Supply Max Current) A1, 5 1) Requires a 5A cable. 2) The Fixed Supply PDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. Requires a 5A cable if over 3A is Advertised. 3) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 4) SPR AVS current for this voltage range is the maximum current as Advertised by the 15V Fixed Supply PDO. This current can be higher than 3A (refer to Note 2). Requires a 5A cable if over 3A is Advertised. 5) The Sink is allowed to request up to the 20V Fixed Supply Max Current when the requested voltage is 15.0V. 6) The Max Voltage for SPR AVS is what is allowed by Table 10.2, "SPR Normative Voltages and Minimum Currents" based on the port's Port Maximum PDP. 7) This SPR Fixed Supply voltage is only available if allowed by Table 10.2, "SPR Normative Voltages and Minimum Currents" based on the port's Port Maximum PDP. 8) SPR Sources May offer (A)PDOs at this Port Present PDP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 999 In reference to Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP", Table 10.4, "SPR Source Port Present PDP less than Port Maximum PDP Examples" gives examples of which SPR capabilities are Advertised based on Port Present PDP on a Managed Capability Port and the port's Port Maximum PDP and cable's current rating. Table 10.4 SPR Source Port Present PDP less than Port Maximum PDP Examples Port Maximum PDP and Cable Rating Port Present PDP Offers 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS 80W / 5A 65W 3A1 3A1 3A1 3.25A 9V – 15V: 3A 15V – 20V: 3.25A 80W / 5A 40W 3A1 3A1 2.67A 2A 9V – 15V: 2.67A 15V – 20V: 2A 80W / 3A 40W 3A1 3A 2.67A 2A 9V – 15V: 2.67A 15V – 20V: 2A 40W / 5A 40W 3A1 3A1 2.67A Not Offered 9V – 15V: 2.67A 40W / 3A 40W 3A1 3A 2.67A Not Offered 9V – 15V: 2.67A 80W / 5A 20W 3A1 2.22A 1.33A 1A 9V – 15V: 1.33A 15V – 20V: 1A 80W / 3A 20W 3A1 2.22A 1.33A 1A 9V – 15V: 1.33A 15V – 20V: 1A 40W / 5A 20W 3A1 2.22A 1.33A Not Offered 9V – 15V: 1.33A 40W / 3A 20W 3A1 2.22A 1.33A Not Offered 9V – 15V: 1.33A 80W/3A 15W 3A 1.67A2 1A2 0.75A2 9V - 15V: 1A2 15V - 20V: 0.75A2 40W/3A 15W 3A 1.67A2 1A2 Not offered 9V - 15V: 1A2 1) The Fixed Supply PDO Maximum Current field will Advertise at least 3A but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. 2) These Capabilities are not required but may be offered at this Port Present PDP. Page 1000 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.2.1 Fixed Supply PDOs Figure 10.1, "SPR Source Power Rule Illustration for Fixed Supply PDOs" illustrates the minimum current that an SPR Source Shall support at each voltage for a given PDP Rating for Fixed Supply PDOs. Note: Not illustrated are that currents higher than 3A are allowed to be offered up to a limit of 5A given that a 5A cable is detected by the Source and the voltage times current remains within the Source PDP Rating. Figure 10.1 SPR Source Power Rule Illustration for Fixed Supply PDOs Figure 10.2, "SPR Source Power Rule Example For Fixed Supply PDOs" shows an example of an adapter with a rating at 50W. The adapter is required to support 20V at 2.5A, 15V at 3A, 9V at 3A and 5V at 3A. 0 1 2 3 4 5 6 0 10 20 30 40 50 60 70 80 90 100 5V 9V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 15W 27W 45W Source PDP Rating (W) Current (A) RP1 RP2 20V 5 + 9 + 15V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1001 Figure 10.2 SPR Source Power Rule Example For Fixed Supply PDOs Table 10.5, "Fixed Supply PDO - Source 5V", Table 10.6, "Fixed Supply PDO - Source 9V", Table 10.7, "Fixed Supply PDO - Source 15V" and Table 10.8, "Fixed Supply PDO - Source 20V" show the Fixed Supply PDOs that Shall be supported for each of the Normative voltages defined in Table 10.2, "SPR Normative Voltages and Minimum Currents". Table 10.5 Fixed Supply PDO - Source 5V Bit(s) Description B31…30 Fixed Supply B29 Dual-Role Power B28 USB Suspend Supported B27 Unconstrained Power B26 USB Communications Capable B25 Dual-Role Data B24 Unchunked Extended Messages Supported B23 EPR Capable B22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 5V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 15 x ÷ 5 15 < x ≤ 25 3 ≤ A ≤ x ÷ 5 25 < x ≤ 100 3 ≤ A ≤ 5 0 1 2 3 4 5 6 0 10 20 30 40 50 60 70 80 90 100 5V 9V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 15W 27W 45W Source PDP Rating (W) Current (A) RP1 RP2 50W 20V 5 + 9 + 15V Page 1002 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 More current May be offered in the PDOs when Optional voltages/currents are supported and a 5A cable is being used (see Section 10.2.3, "Optional Voltages/Currents"). Table 10.6 Fixed Supply PDO - Source 9V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 9V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 15 PDO not required 15 < x ≤ 27 x ÷ 9 27 < x ≤ 45 3 ≤ A ≤ x ÷ 9 45 < x ≤ 100 3 ≤ A ≤ 5 Table 10.7 Fixed Supply PDO - Source 15V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 15V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 27 PDO not required 27 < x ≤ 45 x ÷ 15 45 < x ≤ 75 3 ≤ A ≤ x ÷ 15 75 < x ≤ 100 3 ≤ A ≤ 5 Table 10.8 Fixed Supply PDO - Source 20V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 20V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 45 PDO not required 45 < x ≤ 100 x ÷ 20 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1003 10.2.2.2 SPR Adjustable Voltage Supply (AVS) For SPR AVS, Figure 10.3, "Valid SPR AVS Operating Region for a Source advertising in the range of 27W < PDP ≤ 45W", Figure 10.4, "Valid SPR AVS Operating Region for a Source advertising in the range of 45W < PDP ≤ 60W" and Figure 10.5, "Valid SPR AVS Operating Region for a Source advertising in the range of 60W < PDP ≤ 100W" illustrate the valid operating region for SPR AVS RDO requests in the ranges of 27W < PDP ≤ 45W, 45W < PDP ≤ 60W and 60W < PDP ≤ 100W, respectively. Figure 10.3 Valid SPR AVS Operating Region for a Source advertising in the range of 27W < PDP ≤ 45W Figure 10.4 Valid SPR AVS Operating Region for a Source advertising in the range of 45W < PDP ≤ 60W 0 1 2 3 4 5 6 0 15 30 45 60 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V 15V Fixed PDO Max Current 15V 0 1 2 3 4 5 6 30 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V 15V Fixed PDO Max Current 15V 20V Fixed PDO Max Current (Minimum of 3A) Page 1004 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 10.5 Valid SPR AVS Operating Region for a Source advertising in the range of 60W < PDP ≤ 100W 10.2.2.2.1 SPR Adjustable Voltage Supply (AVS) Voltage Ranges Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" shows the Minimum and Maximum Voltage for the SPR AVS ranges. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. Table 10.9 SPR Adjustable Voltage Supply (AVS) Voltage Ranges AVS Voltage Range 15V AVS 20V AVS Maximum Voltage 15V 20V Minimum Voltage 9V 9V 0 1 2 3 4 5 6 30 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V * At 15.0V, up to the (20V Fixed PDO Current)A is allowed 15V* 20V Fixed PDO Max Current 15V Fixed PDO Max Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1005 10.2.3 Optional Voltages/Currents 10.2.3.1 Optional Normative Fixed, Variable and Battery Supply In addition to the voltages and currents specified in Section 10.2.2, "Normative Voltages and Currents", an SPR Source that is optimized for use with a specific Sink or a specific class of Sinks May Optionally supply additional voltages and increased currents. However, the Optional voltages Shall Not exceed 9V. Optional voltages Shall Not be implemented on EPR Source including for both SPR Mode and EPR Modes of operation. EPR versions of Variable Supply and Battery Supply PDOs are not defined and Shall Not be implemented, however SPR Variable Supply and Battery Supply PDOs are allowed in EPR Mode. While allowed, the use of Optional voltages and currents is not recommended as two Sources with the same PDP Rating but not supporting the same Optional voltages and currents can behave differently thus confusing the user. See Section 10.2, "Source Power Rules" for the rules that Shall apply to Optional PDOs in order to be consistent with the declared PDP Rating and the Normative voltages and currents. 10.2.3.2 Optional Normative SPR Programmable Power Supply The voltages and currents a Programmable Power Supply with a PDP Rating of x Watts Shall support are as defined Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". When Optional Programmable Power Supply APDOs are offered, the following requirements Shall apply:  A Source that Advertises Optional Programmable Power Supply APDOs Shall Advertise the PDOs and APDOs shown in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP".  A Source Shall Advertise Optional Programmable Power Supply APDOs with Maximum Voltage and Minimum Voltages for nominal voltage as defined in Table 10.11, "SPR Programmable Power Supply Voltage Ranges".  A Source Shall Not Advertise a Programmable Power Supply APDO that does not follow the Minimum Voltage and Maximum Voltage defined in Table 10.11, "SPR Programmable Power Supply Voltage Ranges".  In no case Shall a Source Advertise a current that exceeds the Attached cable's current rating.  The Max Voltage Shall Not exceed 21V while in SPR Mode. Table 10.10 SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP PDP Maximum PDP (W) SPR Fixed and AVS 9V Prog3 15V Prog3 20V Prog3 x < 15W Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) - - - 15W - - - 15 < x < 27W (PDP/9)A1 - - 27W 3A - - 27 < x < 45W 3A2 (PDP/15)A1 - 45W - 3A - 45 < x < 60W - 3A2 (PDP/20)A1 60W - - 3A 60 < x < 100W - - (PDP/20)A1 100W - - 5A 1) The SPR PPS APDOs Maximum Current field Shall Advertise RoundDown (PDP/Prog Voltage) to the nearest 50mA. 2) The SPR PPS APDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundDown(PDP/Prog Voltage) to the nearest 50mA. 3) Applies to APDOs regardless of value of the PPS Power Limited bit. Page 1006 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.3.2.1 SPR Programmable Power Supply Voltage Ranges The SPR PPS Voltage ranges map to the Fixed Supply Voltages. For each fixed voltage there is a defined voltage range for the matching SPR PPS APDO. Table 10.11, "SPR Programmable Power Supply Voltage Ranges" shows the Minimum and Maximum Voltage for the Programmable Power Supply that corresponds to the Fixed nominal voltage. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. 10.2.3.2.2 Examples of the use of SPR Programmable Power Supplies The following examples illustrate what a power adapter that Advertises a particular PDP Rating May offer: 1) PDP 27W implementation includes:  5V @ 3A,  9V @ 3A, and  9V Prog @ 3A. 2) PDP 36W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 2.4A,  SPR AVS with 9V - 15V @ 2.4A,  9V Prog @ 3 A, and  15V Prog @ 2.4A. 3) PDP 36W implementation that Optionally includes higher current in the 9V Prog PPS:  5V @ 3A,  9V @ 3A,  15 @ 2.4A,  SPR AVS with 9V - 15V @ 2.4A,  9V Prog @ >3A up to 4A (with a 5A cable) and 15V  Prog @ 2.4A. 4) PDP 50W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 3A,  20V @ 2.5A, Table 10.11 SPR Programmable Power Supply Voltage Ranges Fixed Nominal Voltage 9V Prog 15V Prog 20V Prog Maximum Voltage 11V 16V 21V Minimum Voltage 5V 5V 5V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1007  SPR AVS with 9V - 15V @ 3A & 15V - 20V @ 2.5A,  15V Prog @ 3A, and  20V Prog @ 2.5A. 5) PDP 80W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 3A,  20V @ 4A,  SPR AVS with 9V - 15V @ 3A & 15V - 20V @ 4A,  15V Prog @ 3A, and  20V Prog @ 4A. The first example illustrates a basic example of a supply that can only support 5V and 9V. The second and third examples illustrates as the PDP Rating goes higher there are more possible combinations that meet the Power Rules. These examples also add SPR AVS. Although there are multiple ways to meet the Power Rules, while operating in SPR Mode no more than a combination of seven SPR (A)PDOs and APDOs can be offered. The fourth and fifth example show that the 15V Prog @ 3A fully covers the 9V Prog @3A range so it is not necessary to Advertise both. These examples also illustrate SPR AVS being extended up to 20V with separate current limits for the 9V - 15V and 15V - 20V ranges - a single SPR AVS APDO covers advertising both ranges. Page 1008 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.3.3 Optional Normative Extended Power Range (EPR) Support of EPR Mode is Optional. An EPR Capable port has a PDP Rating that is >100W and ≤ 240W. An EPR Capable Source Port (EPR Source Port) May operate in either SPR Mode or EPR Mode when operating at 100W or less. An EPR Source Port operating in SPR Mode May offer less than 100W to avoid violating safety regulations. When operating in EPR Mode, an EPR Source Port Shall offer 100W in Fixed 20V when not constrained by multi- port sharing limits. An EPR Source May include multiple ports and these ports can be functionally implemented as Shared Capacity Charger or Assured Capacity Charger ports as defined in [USB Type-C 2.4]. Any port on an EPR Source that has a Port Present PDP of 100W or less Shall follow the Normative requirements for SPR Source Ports and Shall operate only in SPR Mode. Any port on an EPR Source that is operating with a cable that is not EPR Capable Shall operate only in SPR Mode. An EPR Source, when operating in SPR Mode with a 5A cable, May offer less than 5A due to design tolerances in order to meet applicable safety standards. For best user experience it Should be as close to 100W as possible. Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR- capable cable" define the Normative requirements EPR Source Ports. While not included in these tables, any EPR Source Port that also supports SPR PPS Shall offer the SPR Fixed 20V PDO and PPS 20V Prog APDO at 100W (or the maximum available PDP when the port is operating at an Equivalent PDP <100W) when in EPR Mode:  When an EPR Source Port is capable of supplying its PDP Rating, it Shall adhere to the requirements defined in Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on its PDP Rating of x Watts.  When a Source Port on an EPR Charger is unable to provide its Port Maximum PDP, it Shall adhere to the requirements defined in Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable" based on a Port Present PDP of x Watts. Some examples:  An EPR Source Port May be unable to provide its PDP Rating because it is thermally constrained at the time of power Negotiation.  A Shared port on a multi-port EPR Charger that is limited by the remaining available power.  When an EPR Charger is in an Adjustable Voltage Supply (AVS) Explicit Contract:  It Shall Reject all Requests outside of the defined voltage range (see Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges") or for a requested voltage and Current that results in a power level that is more than the Port's Advertised PDP.  In no case Shall a Source Advertise a Current or accept a Current requested by a Sink that exceeds the Attached cable's current rating. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1009  The Max Voltage offered by an EPR Source Shall Not exceed 48V. Table 10.12 EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable Port Maximum PDP (W) SPR Fixed and AVS 28V Fixed 36V Fixed3 48V Fixed EPR AVS3, 4 100 < x ≤ 140 Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) (PDP/28)A2 N/A1 N/A1 (15V – PDP/5A):  5A (>PDP/5A – 28V):  (PDP/AVS voltage) A 140 < x ≤ 180 5A (PDP/ 36)A2 N/A1 (15V – PDP/5A):  5A (>PDP/5A – 36V):  (PDP/AVS voltage) A 180 < x ≤ 240 5A 5A (PDP/48)A2 (15V – PDP/5A):  5A (>PDP/5A – 48V):  (PDP/AVS voltage) A 1) EPR Sources are disallowed from offering Fixed Supply voltages that are above the defined voltages for a given PDP, e.g., 36V is disallowed for any PDP of 140W or lower. 2) The Fixed PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 3) EPR Sources Shall reject any request for more than the Advertised PDP, i.e., when output voltage and operating current requested in the Sink RDO is outside of the defined AVS voltage and current range represented by the Advertised PDP, the RDO will be rejected. 4) The current available for a given AVS voltage is as indicated in this column. The current defined here is describing the top edge of the Valid Operating Region as illustrated in Figure 10.6, "Valid EPR AVS Operating Region". The AVS APDO does not have a Maximum Current field, so the maximum current has to be calculated from the PDP. Page 1010 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: EPR Managed Capability Ports when power constrained are defined to offer higher voltages at lower Port Present PDP (as per Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable") than the port's Port Maximum PDP (as per Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable") because these voltages would otherwise be available if the Managed Capability Port power hadn't been constrained. Managed Capability Ports are required to be properly identified to the user based on the port's Port Maximum PDP. In reference to Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable", Table 10.14, "EPR Source Examples when Port Present PDP is less than Port Maximum PDP" gives examples of which EPR Capabilities, in addition to the required SPR Fixed Supply PDOs and SPR AVS APDO, are Advertised based on Port Present PDP and the port's Port Maximum PDP. Table 10.13 EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable Port Present PDP (W) SPR Fixed and AVS 28V Fixed 36V Fixed4 48V Fixed4 EPR AVS with Max Voltage of 28V, 36V or 48V per Table 10.122, 5, 6 28V 36V 48V 7.5 ≤ x ≤ 15 Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) (PDP/28) A3 (PDP/36) A3 (PDP/48) A3  (15V – max voltage):  (PDP/AVS Voltage) A3 15 < x ≤ 27 27 < x ≤ 45 (PDP/28) A1 45 < x ≤ 60 (PDP/36) A1 60 < x ≤ 100 (PDP/48) A1 Up to 75W:  (15V – max voltage):  (PDP/AVS voltage) A Above 75W:  (15V – PDP/5A):  5A  (>PDP/5A – max voltage):  (PDP/AVS voltage) A 100 < x ≤ 140 Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" with a Port Present PDP of 100W. 140 < x ≤ 180 5A 180 < x ≤ 240 5A 5A 1) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 2) EPR Sources Shall reject any Request for more than the Advertised PDP, i.e., when output voltage and operating current requested in the Sink RDO is outside of the defined AVS voltage and current range represented by the Advertised PDP, the RDO will be rejected. 3) EPR Sources May offer an (A)PDOs at this Port Present PDP. When offered, the Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/Voltage) or RoundUp (PDP/Voltage) to the nearest 10mA. 4) This EPR Fixed Supply voltage is only available if allowed by Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on the port’s PDP Rating. 5) The Max Voltage for AVS is what is allowed by TTable 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on the port’s Port Maximum PDP. 6) The current available based on AVS voltage is as indicated in this column. The current defined here is describing the top edge of the Valid Operating Region as illustrated in Figure 10.6, "Valid EPR AVS Operating Region". AVS APDO does not have a Maximum Current field so the maximum current has to be calculated from the PDP. Table 10.14 EPR Source Examples when Port Present PDP is less than Port Maximum PDP Port Maximum PDP Port Present PDP Offers 28V Fixed 36V Fixed 48V Fixed AVS 200W 108W 3.86A 3A 2.25A 48V@108W 160W 108W 3.86A 3A Not offered 36V@108W 120W 108W 3.86A Not offered Not offered 28V@108W 200W 72W 2.57A 2A 1.5A 48V@72W 160W 72W 2.57A 2A Not offered 36V@72W 120W 72W 2.57A Not offered Not offered 28V@72W 200W 36W 1.29A 1A1 0.75A1 48V@36W1 1) These Capabilities are not required but may be offered at this Port Present PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1011 EPR Sources when operating in an AVS Explicit Contract are required to stay within their PDP as such they Shall respond to any request (VA) for more than the PDP with a Reject Message. Figure 10.6, "Valid EPR AVS Operating Region" illustrates the definition of the Valid operating range for an EPR Source operating in an AVS Explicit Contract based on its Advertised PDP. Figure 10.6 Valid EPR AVS Operating Region Figure 10.7, "EPR Source Power Rule Illustration for Fixed PDOs" illustrates the minimum current that an EPR Source Shall support at each voltage for a given PDP Rating. Note: Not illustrated are that currents higher than 3A are allowed to be offered up to a limit of 5A given that a 5A cable is detected by the Source and the voltage times current remains within the Source PDP Rating. 160W 36W 1.29A 1A1 Not offered 36V@36W1 120W 36W 1.29A Not offered Not offered 28V@36W Table 10.14 EPR Source Examples when Port Present PDP is less than Port Maximum PDP Port Maximum PDP Port Present PDP Offers 28V Fixed 36V Fixed 48V Fixed AVS 1) These Capabilities are not required but may be offered at this Port Present PDP. 0 1 2 3 4 5 6 0 15 30 45 60 RDO Current (A) RDO Voltage (V) 5A Invalid Requests (Crosshatched Area) Valid Operating Region for EPR AVS Sink Requests Valid RDO Requests Advertised Voltage = 28, 36 or 48V 15V Voltage = PDP/5A Current = Advertised PDP/Advertised Voltage Page 1012 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 10.7 EPR Source Power Rule Illustration for Fixed PDOs 10.2.3.3.1 EPR Adjustable Voltage Supply (AVS) Voltage Ranges Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" shows the Minimum and Maximum Voltage for the EPR AVS ranges. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. Table 10.15 EPR Adjustable Voltage Supply (AVS) Voltage Ranges AVS Voltage Ranges 28V AVS 36V AVS 48V AVS Maximum Voltage 28V 36V 48V Minimum Voltage 15V 15V 15V 0 1 2 3 4 5 6 0 20 40 60 80 100 Source PDP Rating (W) Current (A) 120 140 160 180 200 220 240 RP1 RP2 5V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 27W 45W 15W 100W 140W 180W 20V 9V 5 + 9 + 15V 5 + 9 + 15V 28V 36V 48V 5 + 9 + 15V 5 + 9 + 15V 20V 20+28V 20+28+36V
10.3 - Sink Power Rules...................................................................................................................... (Page 1013)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1013 10.3 Sink Power Rules 10.3.1 Sink Power Rule Considerations The Sink Power Rules are designed to ensure the best possible user experience when a given Sink used with a compliant Source of arbitrary Output Power Rating that only supplies the Normative voltages and currents. The Sink Power Rules are based on the following considerations:  Low power Sources (e.g., 5V) are expected to be very common and will be used with Sinks designed for a higher PDP.  Optimizing the user experience when Sources with a higher PDP Rating are used with low power Sinks.  Preventing Sinks that only function well (or at all) when using Optional voltages and currents. 10.3.2 Normative Sink Rules Sinks designed to use Sources with a PDP Rating of x W Shall:  Either operate or charge from Sources that have a PDP Rating ≥ x W.  Either operate, charge or indicate a Capabilities Mismatch (see Section 6.4.2.3, "Capability Mismatch") from Sources that have a PDP Rating < x W and ≥ 0.5W. A Sink optimized for a Source with Optional voltages and currents or power as described in Section 10.2.3, "Optional Voltages/Currents" with a PDP Rating of x W Shall provide a similar user experience when powered from a Source with a PDP Rating of ≥ x W that supplies only the Normative voltages and currents as specified in Section 10.2.2, "Normative Voltages and Currents". For example, a 60W Source might not offer 9V Prog or 15V Prog since 20V Prog is a suitable substitute for both (as shown in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP"). The Operational Current/Power in the Sink Capabilities PDO for Sinks with an Operational PDP of x Watts Shall be as follows:  Operational current for Fixed Supply/Variable Supply PDOs: RoundDown(x/voltage) to the nearest 10mA.  Operational power for Battery Supply PDOs: ≤ x.  Operational current for Programmable Power Supply APDOs as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP": RoundDown (x/Prog Voltage) to the nearest 50mA. The Maximum Current/Power in the Sink RDO for Sinks with an Operational PDP of x Watts and Maximum PDP of y Watts Shall be as follows:  Maximum current for Fixed Supply/Variable Supply RDOs from Sinks without a Battery: RoundDown(x/ voltage) to the nearest 10mA.  Maximum current for Fixed Supply/Variable Supply RDOs from Sinks with a Battery: RoundDown(y/ Voltage) to the nearest 10mA.  Maximum power for Battery Supply RDOs from Sinks without a Battery: ≤ x.  Maximum power for Battery Supply RDOs from Sinks with a Battery: ≤ y.  Maximum current for PPS Supply RDOs from Source PDOs as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" or Table 10.14, "EPR Source Examples when Port Present PDP is less than Port Maximum PDP": RoundDown (y/Prog Voltage) to the nearest 50mA. The following requirements Shall apply to the Advertised Sink Capabilities:
6 - Protocol Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 114)
Page 114 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6 Protocol Layer 6.1 Overview This chapter describes the requirements of the USB Power Delivery Specification's Protocol Layer including:  Details of how Messages are constructed and used.  Use of timers and timeout values.  Use of Message and retry counters.  Reset operation.  Error handling.  State behavior. Refer to Section 2.6, "Architectural Overview" for an overview of the theory of operation of USB Power Delivery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 115 6.2 Messages This specification defines three types of Messages:  Control Messages that are short and used to manage the Message flow between Port Partners or to exchange Messages that require no additional data. Control Messages are 16 bits in length.  Data Messages that are used to exchange information between a pair of Port Partners. Data Messages range from 48 to 240 bits in length.  Some examples of Data Messages are:  Those used to expose Capabilities and Negotiate power.  Those used for the BIST.  Those that are Vendor Defined Messages.  Extended Messages that are used to exchange information between a pair of Port Partners. Extended Messages are up to MaxExtendedMsgLen bytes.  Some examples of Extended Messages are:  Those used for Source and Battery information.  Those used for Security.  Those used for Firmware Update.  Those that are Vendor Defined Extended Messages. 6.2.1 Message Construction All Messages Shall be composed of a Message Header and a variable length (including zero) data portion. A Message either originates in the Protocol Layer and is passed to the PHY Layer, or it is received by the PHY Layer and is passed to the Protocol Layer. Figure 6.1, "USB Power Delivery Packet Format for a Control Message" illustrates a Control Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.1 USB Power Delivery Packet Format for a Control Message Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload" illustrates a Data Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Legend: PHY Layer Protocol Layer Page 116 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.2 USB Power Delivery Packet Format including Data Message Payload Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" illustrates an Extended Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.3 USB Power Delivery Packet Format including an Extended Message Header and Payload 6.2.1.1 Message Header Every Message Shall start with a Message Header as shown in:  Figure 6.1, "USB Power Delivery Packet Format for a Control Message"  Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload"  Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and as defined in Table 6.1, "Message Header". The Message Header contains basic information about the Message and the PD Port Capabilities. The Message Header May be used standalone as a Control Message when the Number of Data Objects field is zero or as the first part of a Data Message when the Number of Data Objects field is non-zero. 6.2.1.1.1 Extended The 1-bit Extended field Shall be set to zero to indicate a Control Message or Data Message and set to one to indicate an Extended Message. Table 6.1 Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Extended Section 6.2.1.1.1 14…12 SOP* Number of Data Objects Section 6.2.1.1.2 11…9 SOP* MessageID Section 6.2.1.1.3 8 SOP only Port Power Role Section 6.2.1.1.4 SOP’/SOP’’ Cable Plug Section 6.2.1.1.7 7…6 SOP* Specification Revision Section 6.2.1.1.5 5 SOP only Port Data Role Section 6.2.1.1.6 SOP’/SOP’’ Reserved Section 1.4.2 4…0 SOP* Message Type Section 6.2.1.1.8 Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) 0..7 Data Object(s) Legend: PHY Layer Protocol Layer Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Data (0..260 bytes) Legend: PHY Layer Protocol Layer Extended Message Header (16 bit) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 117 The Extended field Shall apply to all SOP* Packet types. 6.2.1.1.2 Number of Data Objects When the Extended field is set to zero the 3-bit Number of Data Objects field Shall indicate the number of 32-bit Data Objects that follow the Message Header. When this field is zero the Message is a Control Message and when it is non-zero, the Message is a Data Message. The Number of Data Objects field Shall apply to all SOP* Packet types. When both the Extended bit and Chunked bit are set to one, the Number of Data Objects field Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. When the Extended bit is set to one and Chunked bit is set to zero, the Number of Data Objects field Shall be Reserved. Note: In this case, the Message length is determined solely by the Data Size field in the Extended Message Header. 6.2.1.1.3 MessageID The 3-bit MessageID field is the value generated by a rolling counter maintained by the originator of the Message. The MessageIDCounter Shall be initialized to zero at power-on as a result of a Soft Reset, or a Hard Reset. The MessageIDCounter Shall be incremented when a Message is successfully received as indicated by receipt of a GoodCRC Message. Note: The usage of MessageID during testing with BIST Messages is defined in [USBPDCompliance]. The MessageID field Shall apply to all SOP* Packet types. 6.2.1.1.4 Port Power Role The 1-bit Port Power Role field Shall indicate the Port's present Power Role:  0b Sink  1b Source Messages, such as Get_Sink_Cap_Extended, that are only ever sent by a Source, Shall always have the Port Power Role field set to Source. Similarly, Messages such as the Request Message that are only ever sent by a Sink Shall always have the Port Power Role field set to Sink. During the Power Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that the Initial Source's power supply is turned off (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Power Role Swap AMS, for the Initial Sink, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that VBUS is not being driven by the Initial Source and is within vSafe5V (see Figure 8.39, "Successful Fast Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Sink Port, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Figure 8.39, "Successful Fast Role Swap Sequence"). Note: The GoodCRC Message sent by the Initial Sink in response to the PS_RDY Message from the Initial Source will have its Port Power Role field set to Sink since this is initiated by the Protocol Layer. Subsequent Page 118 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Messages initiated by the Policy Engine, such as the PS_RDY Message sent to indicate that VBUS is ready, will have the Port Power Role field set to Source. The Port Power Role field of a received Message Shall Not be verified by the receiver and Shall Not lead to Soft Reset, Hard Reset or Error Recovery if it is incorrect. The Port Power Role field Shall only be defined for SOP Packets. 6.2.1.1.5 Specification Revision The Specification Revision field Shall be one of the following values (except 11b):  00b - Revision 1.0 (Deprecated)  01b - Revision 2.0  10b - Revision 3.x  11b - Reserved, Shall Not be used. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every PD Specification Revision starting from [USB 2.0] for SOP*; the only exception to this is a VPD which Shall Ignore Messages sent with PD Specification Revision 2.0 and earlier. After a physical or logical (USB Type-C® Error Recovery) Attach, a Port discovers the common Specification Revision level between itself and its Port Partner and/or the Cable Plug(s), and uses this Specification Revision level until a Detach, Hard Reset or Error Recovery happens. After detection of the Specification Revision to be used, all PD communications Shall comply completely with the relevant Revision of the PD specification. The 2-bit Specification Revision field of a GoodCRC Message does not carry any meaning and Shall be considered as don't care by the recipient of the Message. The sender of a GoodCRC Message Shall set the Specification Revision field to 01b (Revision 2.0) when responding to a Message that contains 01b in the Specification Revision field of the Message Header. The sender of a GoodCRC Message May set the Specification Revision field to 01b or 10b when responding to a Message that contains 10b (Revision 3.x) in the Specification Revision field of the Message Header. The Specification Revision field Shall apply to all SOP* Packet types. An Attach event or a Hard Reset Shall cause the detection of the applicable Specification Revision to be performed for both Ports and Cable Plugs according to the rules stated below: When the Source Port first communicates with the Sink Port the Specification Revision field Shall be used as described by the following steps: 1) The Source Port sends a Source_Capabilities Message to the Sink Port setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Source Port supports. 2) The Sink Port responds with a Request Message setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Sink Port supports that is equal to or lower than the Specification Revision received from the Source Port. 3) The Source and Sink Ports Shall use the Specification Revision in the Request Message from the Sink in step 2 in all subsequent communications until a Detach, Hard Reset, or Error Recovery happens. Prior to entering the First Explicit Contract, the VCONN Source Shall use the following steps to establish a Specification Revision level: 1) The VCONN Source sends a Discover Identity REQ to the Cable Plug (SOP’) setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports. After a VCONN Swap the required Soft_Reset / Accept Message exchange is used for the same purpose (see Section 6.3.13, "Soft Reset Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 119 2) The Cable Plug responds with a Discover Identity ACK setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports that is equal to or lower than the Specification Revision it received from the Source Port. 3) The Cable Plug and VCONN Source Shall communicate using the lower of the two revisions until an Explicit Contract has been established. 4) Table 6.2, "Revision Interoperability during an Explicit Contract" shows the Specification Revision that Shall be used between the Port Partners and the Cable Plugs when the Specification Revision has been discovered and an Explicit Contract is in place. Notes:  A VCONN Source that does not communicate with the Cable Plug(s) May skip the above procedure.  When a Cable Plug does not respond to a Revision 3.x Discover Identity REQ with a Discover Identity ACK or BUSY the VCONN Source May repeat steps 1-4 using a Revision 2.0 Discover Identity REQ in step 1 before establishing that there is no Cable Plug to communicate with. A VCONN Source that supports Revision 3.x of the Power Delivery Specification May communicate with a Cable Plug also supporting Revision 3.x using Revision 3.x Compliant Communications regardless of the Specification Revision of its Port Partner while no Explicit Contract exists. After an Explicit Contract has been established the Port Partners and Cable Plug(s) Shall use Table 6.2, "Revision Interoperability during an Explicit Contract" to determine the Revision to be used. All data in all Messages Shall be consistent with the Specification Revision field in the Message Header for that particular Message. A Cable Plug Shall Not save the state of the agreed Specification Revision. A Cable Plug Shall respond with the highest Specification Revision it supports that is equal to or lower than the Specification Revision contained in the Message received from the VCONN Source. Cable Plugs Shall operate using the same Specification Revision for both SOP’ and SOP’’. Cable assemblies with two Cable Plugs Shall operate using the same Specification Revision for both Cable Plugs. See Table 6.2, "Revision Interoperability during an Explicit Contract" for details of how various Revisions Shall inter-operate. 6.2.1.1.6 Port Data Role The 1-bit Port Data Role field Shall indicate the Port's present Data Role:  0b UFP  1b DFP Table 6.2 Revision Interoperability during an Explicit Contract Port 1 Revision Cable Plug Revision Port 2 Revision Port to Port Operating Revision Port to Cable Plug Operating Revision 2 2 2 2 2 2 2 3 2 2 2 3 2 2 2 2 3 3 2 2 3 2 2 2 2 3 2 3 3 2 3 3 2 2 2 3 3 3 3 3 Page 120 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Port Data Role field Shall only be defined for SOP Packets. For all other SOP* Packets the Port Data Role field is Reserved and Shall be set to zero. If a USB Type-C Port receives a Message with the Port Data Role field set to the same Data Role as its current Data Role, except for the GoodCRC Message, USB Type-C Error Recovery actions as defined in [USB Type-C 2.4] Shall be performed. For a USB Type-C Port the Port Data Role field Shall be set to the default value at Attachment after a Hard Reset: 0b for a Port with Rd asserted and 1b for a Port with Rp asserted. In the case that a Port is not USB Communications capable, at Attachment a Source Port Shall default to DFP and a Sink Port Shall default to UFP. 6.2.1.1.7 Cable Plug The 1-bit Cable Plug field Shall indicate whether this Message originated from a Cable Plug or VPD:  0b Message originated from a DFP or UFP.  1b Message originated from a Cable Plug or VPD The Cable Plug field Shall only apply to SOP’ Packet and SOP’’ Packet types. 6.2.1.1.8 Message Type The 5-bit Message Type field Shall indicate the type of Message being sent. To fully decode the Message Type, the Number of Data Objects field is first examined to determine whether the Message is a Control Message or a Data Message. Then the specific Message Type can be found in Table 6.5, "Control Message Types" or Table 6.6, "Data Message Types". The Message Type field Shall apply to all SOP* Packet types. 6.2.1.2 Extended Message Header Extended Messages (indicated by the Extended field being set in the Message Header) Shall contain an Extended Message Header following the Message Header as shown in Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and defined in “Table 6.3, "Extended Message Header". Extended Messages contain Data Blocks of Data Size, defined in the Extended Message, that are either sent in a single Message or as a series of Chunks. When the Data Block is sent as a series of Chunks, each Chunk in the series, except for the last Chunk, Shall contain MaxExtendedMsgChunkLen bytes. The last Chunk in the series Shall contain the remainder of the Data Block and so could be less than MaxExtendedMsgChunkLen bytes and Shall be padded to the next 4-byte Data Object boundary. 6.2.1.2.1 Chunked The Port Partners Shall use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine whether to send Messages of Data Size > MaxExtendedMsgLegacyLen bytes in a single Unchunked Extended Message (see Section 6.4.1.2.1.6, "Unchunked Extended Messages Supported" and Section 6.4.2.6, "Unchunked Extended Messages Supported"). Table 6.3 Extended Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Chunked Section 6.2.1.2.1 14…11 SOP* Chunk Number Section 6.2.1.2.2 10 SOP* Request Chunk Section 6.2.1.2.3 9 SOP* Reserved 8…0 SOP* Data Size Section 6.2.1.2.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 121 When either Port Partner only supports Chunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to one.  Every Extended Message of Data Size > MaxExtendedMsgLegacyLen Shall be transmitted between the Port Partners in Chunks  The Number of Data Objects in the Message Header Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When both Port Partners support Unchunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to zero.  Every Extended Message Shall be transmitted between the Port Partners Unchunked.  The Number of Data Objects in the Message Header is Reserved. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When sending Extended Messages to the Cable Plug the VCONN Source Shall only send Chunked Extended Messages. Cable Plugs Shall always send Extended Messages of Data Size > MaxExtendedMsgLegacyLen Chunked and Shall set the Chunked bit in every Extended Message to one. When Extended Messages are supported Chunking Shall be supported. 6.2.1.2.2 Chunk Number The Chunk Number field Shall only be Valid in a Message if the Chunked flag is set to one. If the Chunked flag is set to zero the Chunk Number field Shall also be set to zero. The Chunk Number field is used differently depending on whether the Message is a request for Data, or a requested Data Block being returned:  In a request for data the Chunk Number field indicates the number of the Chunk being requested. The requester Shall only set this field to the number of the next Chunk in the series (the next Chunk after the last received Chunk).  In the requested Data Block the Chunk Number field indicates the number of the Chunk being returned. The Chunk Number for each Chunk in the series Shall start at zero and Shall increment for each Chunk by one up to a maximum of 9 corresponding to 10 Chunks in total. 6.2.1.2.3 Request Chunk The Request Chunk bit Shall only be used for the Chunked transfer of an Extended Message when the Chunked bit is set to 1 (see Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)"). For Unchunked Extended Message transfers, Messages Shall be sent and received without the request/response mechanism (see Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)"). The Request Chunk bit Shall be set to one to indicate that this is a request for a Chunk of a Data Block and Shall be set to zero to indicate that this is a Chunk response containing a Chunk. Except for Chunk zero, a requested Chunk of a Data Block Shall only be returned as a Chunk response to a corresponding request for that Chunk. Both the Chunk request and the Chunk response Shall contain the same value in the Message Type field. When the Request Chunk bit is set to one the Data Size field Shall be zero. Page 122 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.2.1.2.4 Data Size The Data Size field Shall indicate how many bytes of data in total are in Data Block being returned. The total number of data bytes in the Message Shall Not exceed MaxExtendedMsgLen. If the Data Size field is less than MaxExtendedMsgLegacyLen and the Chunked bit is set then the Packet Payload Shall be padded to the next 4-byte Data Object boundary with zeros (0x00). If the Data Size field is greater than expected for a given Extended Message but less than or equal to MaxExtendedMsgLen then the expected fields in the Message Shall be processed appropriately and the additional fields Shall be Ignored. 6.2.1.2.5 Extended Message Examples The following examples illustrate the transmission of Extended Messages both Chunked (Chunked bit is one) and Unchunked (Chunked bit is zero). The examples use a Security_Request Message of Data Size 7 bytes which is responded to by a Security_Response Message of Data Size 30 bytes. The sizes of these Messages are arbitrary and are used to illustrate Message transmission; they are not intended to correspond to genuine security related Messages. During Negotiation of the Explicit Contract after connection, the Port Partners use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine the value of the Chunked bit (see Table 6.4, "Use of Unchunked Message Supported bit"). When both Port Partners support Unchunked Extended Messages then the Chunked bit is zero otherwise the Chunked bit is one. The Chunked bit is used to determine whether:  The Chunk request/response mechanism is used.  Extended Messages are Chunked.  Padding is applied.  The Number of Data Objects field is used. The following examples illustrate the expected usage in each case. 6.2.1.2.5.1 Security_Request/Security_Response Unchunked Example Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Unchunked Extended Messages (Chunked bit is zero) between a USB Host and a Charger. The entire Data Block is returned in one Message. The Chunk request/response mechanism is not used. Table 6.4 Use of Unchunked Message Supported bit Source: Source_Capabilities Message Unchunked Message Supported bit = 0 Unchunked Message Supported bit = 1 Sink: Request Message Unchunked Message Supported bit = 0 Chunked bit = 1 Chunked bit = 1 Unchunked Message Supported bit = 1 Chunked bit = 1 Chunked bit = 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 123 Figure 6.4 Example Security_Request sequence Unchunked (Chunked bit = 0) Figure 6.5, "Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero)" details the Security_Request Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to 0, which in this case is 7 bytes. Figure 6.5 Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero) Figure 6.6, "Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero)" details the Security_Response Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to zero, which in this case is 30 bytes. Host Charger Security_Request (Data Size = 7, Chunked = 0) GoodCRC GoodCRC Security_Response (Data Size = 30, Chunked = 0) Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 0 (Reserved) Data (7 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 Page 124 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.6 Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero) 6.2.1.2.5.2 Security_Request/Security_Response Chunked Example Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Chunked Extended Messages (Chunked bit is one) between a USB Host and a Charger. Note: Chunk Number zero in every Extended Message is sent without the need for a Chunk Request, but Chunk Number one and following need to be requested with a Chunk request. Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 0 (Reserved) Data (30 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B28 B29 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 125 Figure 6.7 Example Security_Request sequence Chunked (Chunked bit = 1) Figure 6.8, "Example Security_Request Message of Data Size 7 (Chunked bit set to 1)" shows the Security_Request Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Three bytes of padding have been added to the Message so that the total number of bytes is a multiple of 32-bits, corresponding to 3 Data Objects. The Number of Data Objects field is set to 3 to indicate the length of this Chunk. The Chunk Number is set to zero and the Data Size field is set to 7 to indicate the length of the whole Extended Message. Host Charger Security_Request (Number of Data Objects = 3, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 7) GoodCRC GoodCRC Security_Response (Number of Data Objects = 7, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 30) Security_Response “Chunk request” (Number of Data Objects = 1, Chunked = 1, Chunk Number = 1, Request Chunk = 1, Data Size = 0) GoodCRC GoodCRC Security_Response (Number of Data Objects = 2, Chunked = 1, Chunk Number = 1, Request Chunk = 0, Data Size = 30) Security_Request Chunk Security_Response Page 126 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.8 Example Security_Request Message of Data Size 7 (Chunked bit set to 1) Figure 6.9, "Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number zero of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. No padding is need for this Chunk since the full 26-byte Payload plus 2-byte Extended Message Header is a multiple of 32-bits, corresponding to 7 Data Objects. The Number of Data Objects field is set to 7 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.9 Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" shows an example of the Message format, byte ordering and padding for the Security_Response Message Chunk request for Chunk Number one shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)". In the Chunk request the Number of Data Objects field in the Message is set to 1 to indicate that the Payload is 32 bits equivalent to 1 data object (see Figure 6.10, "Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1)"). Since the Chunked bit is set to 1 the Chunk request/Chunk response mechanism is used. The Message is a Chunk request so the Request Chunk bit is set to one, and in this case Chunk one is being requested so Chunk Number is set to one. Data Size is set to zero indicating the length of the Data Block being transferred. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits. Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 3 Data (7 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 P0 (0x00) P1 (0x00) P2 (0x00) Padding (3 bytes) Data Object 0 Data Object 1 Data Object 2 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 7 Data (26 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B22 B23 Data Object 0 B24 B25 Data Object 6 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 127 Figure 6.10 Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1) Figure 6.11, "Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number one of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits, corresponding to 2 Data Objects. The Number of Data Objects field is set to 2 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.11 Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 1 Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 1 Data Size = 0 Message Header LSB Message Header MSB Message Header LSB Message Header MSB P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 2 Data (4 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Data Object 1 Page 128 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3 Control Message A Message is defined as a Control Message when the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. The Protocol Layer originates the Control Messages (i.e., Accept Message, Reject Message etc.). The Control Message types are specified in the Message Header's Message Type field (bits 4…0) and are summarized in Table 6.5, "Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.5 Control Message Types Bits 4…0 Message Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 0_0001 GoodCRC Source, Sink or Cable Plug See Section 6.3.1. SOP* 0_0010 GotoMin (Deprecated) Deprecated See Section 6.3.2. N/A 0_0011 Accept Source, Sink or Cable Plug See Section 6.3.3. SOP* 0_0100 Reject Source, Sink or Cable Plug See Section 6.3.4. SOP* 0_0101 Ping (Deprecated) Deprecated See Section 6.3.5. SOP only 0_0110 PS_RDY Source or Sink See Section 6.3.6. SOP only 0_0111 Get_Source_Cap Sink or DRP See Section 6.3.7. SOP only 0_1000 Get_Sink_Cap Source or DRP See Section 6.3.8. SOP only 0_1001 DR_Swap Source or Sink See Section 6.3.9. SOP only 0_1010 PR_Swap Source or Sink See Section 6.3.10. SOP only 0_1011 VCONN_Swap Source or Sink See Section 6.3.11. SOP only 0_1100 Wait Source or Sink See Section 6.3.12. SOP only 0_1101 Soft_Reset Source or Sink See Section 6.3.13. SOP* 0_1110 Data_Reset Source or Sink See Section 6.3.14. SOP only 0_1111 Data_Reset_Complete Source or Sink See Section 6.3.15. SOP only 1_0000 Not_Supported Source, Sink or Cable Plug See Section 6.3.16. SOP* 1_0001 Get_Source_Cap_Extended Sink or DRP See Section 6.3.17. SOP only 1_0010 Get_Status Source or Sink See Section 6.3.18. SOP* 1_0011 FR_Swap Sink1 See Section 6.3.19. SOP only 1_0100 Get_PPS_Status Sink See Section 6.3.20. SOP only 1_0101 Get_Country_Codes Source or Sink See Section 6.3.21. SOP only 1_0110 Get_Sink_Cap_Extended Source or DRP See Section 6.3.22. SOP only 1_0111 Get_Source_Info Sink or DRP See Section 6.3.23. SOP Only 1_1000 Get_Revision Source or Sink See Section 6.3.24. SOP* 1_1001… 1_1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 1) In this case the Port is providing vSafe5V however it will have Rd asserted rather than Rp and sets the Port Power Role field to Sink, until the Fast Role Swap AMS has completed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 129 6.3.1 GoodCRC Message The GoodCRC Message Shall be sent by the receiver to acknowledge that the previous Message was correctly received (i.e., had a GoodCRC Message). The GoodCRC Message Shall return the Message's MessageID so the sender can determine that the correct Message is being acknowledged. The first bit of the GoodCRC Message Shall be returned within tTransmit after receipt of the last bit of the previous Message. BIST does not send the GoodCRC Message while in a Continuous BIST Mode (see Section 6.4.3, "BIST Message"). The retry mechanism is triggered when the Message sender fails to receive a GoodCRC Message before the CRCReceiveTimer expires. It is used by the Message sender to detect that the Message was not correctly received by the Message recipient due to noise or other disturbance on the Configuration Channel (CC). The retry mechanism Shall Not be used for any other purpose such as a means of gaining time for processing the required response to the received Message. 6.3.2 GotoMin Message (Deprecated) The GotoMin (Deprecated) Message has been Deprecated. The 0_0010 Message Type is no longer Valid and Shall be responded to by a Not_Supported Message. 6.3.3 Accept Message The Accept Message is a Valid response in the following cases:  It Shall be sent by the Source, in SPR Mode, to signal the Sink that the Source is willing to meet the Request Message.  It Shall be sent by the Source, in EPR Mode, to signal the Sink that the Source is willing to meet the EPR_Request Message.  It Shall be sent by the recipient of the PR_Swap Message to signal that it is willing to do a Power Role Swap and has begun the Power Role Swap AMS.  It Shall be sent by the recipient of the DR_Swap Message to signal that it is willing to do a Data Role Swap and has begun the Data Role Swap AMS.  It Shall be sent by the recipient of the VCONN_Swap Message to signal that it is willing to do a VCONN Swap and has begun the VCONN Swap AMS.  It Shall be sent by the recipient of the FR_Swap Message to indicate that it has begun the Fast Role Swap AMS.  It Shall be sent by the recipient of the Soft_Reset Message to indicate that it has completed its Soft Reset.  It Shall be sent by the recipient of the Enter_USB Message to indicate that it has begun the Enter USB AMS.  It Shall be sent by the recipient of the Data_Reset Message to indicate that it has begun the Data Reset AMS. The Accept Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.6.2, "SenderResponseTimer"). 6.3.4 Reject Message The Reject Message is a Valid response in the following cases:  It Shall be sent to signal the Sink, in SPR Mode, that the Source is unable to meet the Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised. Page 130 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  It Shall be sent to signal the Sink, in EPR Mode, that the Source is unable to meet the EPR_Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is unable to do a Power Role Swap.  It Shall be sent by the recipient of a PR_Swap Message while in EPR Mode.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source, to indicate it is unable to do a VCONN Swap.  It Shall be sent by UFP on receiving an Enter_USB Message to indicate it is unable to enter the requested USB Mode. The sender of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message, on receiving a Reject Message response, Shall Not send this same Message to the recipient until one of the following has occurred:  A New Explicit Contract Negotiation as a result of the Source sending a Source_Capabilities Message or EPR_Source_Capabilities Message. This can be triggered by:  The Source's Device Policy Manager.  A Get_Source_Cap Message sent from the Sink to the Source in SPR Mode.  An EPR_Get_Source_Cap Message sent from the Sink to the Source in EPR Mode.  A Power Role Swap.  A Soft Reset.  A Hard Reset.  A Disconnect/Re-connect.  A Data Role Swap.  A Data Reset. The Sink May send a different Request Message to the one which was rejected but Shall Not repeat the same Request Message, using the same RDO, unless there has been a New Explicit Contract Negotiation, Data Role Swap or Data Reset as described above. The Reject Message Shall be sent within tReceiverResponse of the receipt of the last bit of Message (see Section 6.6.2, "SenderResponseTimer"). Note: The Reject Message is not a Valid response when a Message is not supported. In this case the Not_Supported Message is returned (see Section 6.3.16, "Not_Supported Message"). 6.3.5 Ping Message The Ping (Deprecated) Message has been deprecated. The 0_0101 Message Type is no longer Valid. A Port that receives a Ping (Deprecated) Message May respond with a Not_Supported Message or Ignore the Ping (Deprecated) Message. A Cable Plug that receives a Ping (Deprecated) Message Shall Ignore the Ping (Deprecated) Message. 6.3.6 PS_RDY Message The PS_RDY Message Shall be sent by the Source (or by both the New Sink and New Source during the Power Role Swap AMS or Fast Role Swap AMS) to indicate its power supply has reached the desired operating condition (see Section 8.3.2.2, "Power Negotiation"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 131 6.3.7 Get_Source_Cap Message The Get_Source_Cap (Get Source Capabilities) Message May be sent by a Port to request the Source Capabilities and Dual-Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message"). 6.3.8 Get_Sink_Cap Message The Get_Sink_Cap (Get Sink Capabilities) Message May be sent by a Port to request the Sink Capabilities and Dual- Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message"). 6.3.9 DR_Swap Message The DR_Swap Message is used to exchange DFP and UFP operation between Port Partners while maintaining the direction of power flow over VBUS. The Data Role Swap process can be used by Port Partners whether or not they support USB Communications capability. A DFP that supports USB Communication capability starts as the USB Host on Attachment. A UFP that supports USB Communication capability starts as the USB Device on Attachment. [USB Type-C 2.4] Dual-Role Data (DRD) Ports Shall have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. DFPs and UFPs May have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. A Data Role Swap Shall be regarded in the same way as a cable Detach/ Re-attach in relation to any USB Communication which is ongoing between the Port Partners. If there are any Active Modes between the Port Partners when a DR_Swap Message is a received, then a Hard Reset Shall be performed (see Section 6.4.4.3.4, "Enter Mode Command"). If the Cable Plug has any Active Modes then the DFP Shall Not issue a DR_Swap Message and Shall cause all Active Modes in the Cable Plug to be exited before accepting a Data Role Swap request. The source of VBUS and VCONN Source Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the Data Role Swap process. The DR_Swap Message May be sent by either Port Partner. The recipient of the DR_Swap Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait").  If an Accept Message is sent, the Source and Sink Shall exchange Data Roles.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Data Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Data Role Swap might be possible in the future but that no immediate action Shall be taken. Before a Data Role Swap the initial DFP Shall have its Port Data Role bit set to DFP, and the initial UFP Shall have its Port Data Role bit set to UFP. After a successful Data Role Swap the DFP/Host Shall become the UFP/Device and vice-versa; the new DFP Shall have its Port Data Role bit set to DFP, and the new UFP Shall have its Port Data Role bit set to UFP. Where USB Communication is supported by both Port Partners a USB data connection Should be established according to the new Data Roles. If the Data Role Swap, after having been accepted by the Port Partner, is subsequently not successful, in order to attempt a re-establishment of the connection, USB Type-C Error Recovery actions, such as disconnect, as defined in [USB Type-C 2.4] will be necessary. See Section 8.3.2.9, "Data Role Swap". 6.3.10 PR_Swap Message The PR_Swap Message May be sent by either Port Partner to request an exchange of Power Roles. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). Page 132 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If an Accept Message is sent, the Source and Sink Shall do a Power Role Swap.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Power Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Power Role Swap might be possible in the future but that no immediate action Shall be taken. The PR_Swap Message Shall Not be sent while in EPR Mode. While in EPR Mode if a Power Role Swap is required, an EPR Mode exit Shall be done first. After a successful Power Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the New Source Shall also reset its CapsCounter. The New Source Shall have Rp asserted on the CC wire and the New Sink Shall have Rd asserted on the CC wire as defined in [USB Type-C 2.4]. When performing a Power Role Swap from Source to Sink, the Port Shall change its CC wire resistor from Rp to Rd. When performing a Power Role Swap from Sink to Source, the Port Shall change its CC wire resistor from Rd to Rp. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged by the Power Role Swap process. Note: During the Power Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Power Role Swap, refer to:  Section 7.3.2, "Transitions Caused by Power Role Swap"  Section 8.3.2.5, "Data Reset".  Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram".  Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram".  Section 9.1.2, "Mapping to USB Device States". 6.3.11 VCONN_Swap Message The VCONN_Swap Message Shall be supported by any Port that can operate as a VCONN Source. The VCONN_Swap Message May be sent by either Port Partner to request an exchange of VCONN Source. The recipient of the Message Shall respond by sending an Accept Message, Reject Message, Wait Message (see Section 6.9, "Accept, Reject and Wait") or Not_Supported Message.  If an Accept Message is sent, the Port Partners Shall perform a VCONN Swap. The new VCONN Source Shall send a PS_RDY Message within tVcONNSourceOn to indicate that it is now sourcing VCONN. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of receipt of the last bit of the EOP of the PS_RDY Message.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a VCONN Swap and no action Shall be taken. A Reject Message Shall only be sent by the Port that is not presently the VCONN Source in response to a VCONN_Swap Message. The Port that is presently the VCONN Source Shall Not send a Reject Message in response to VCONN_Swap Message.  If a Wait Message is sent, the requester is informed that a VCONN Swap might be possible in the future but that no immediate action Shall be taken. A Port after losing the VCONN Source role due to incoming VCONN Swap request Shall Not initiate a VCONN Swap until at least tVCONNSwapDelayDFP/ tVCONNSwapDelayUFP after completing the previous VCONN Swap AMS.  If a Not_Supported Message is sent, the requester is informed that VCONN Swap is not supported. The Port that is not presently the VCONN Source May turn on VCONN when a Not_Supported Message is received in response to a VCONN_Swap Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 133 The DFP (Host), UFP (Device) Data Roles and Source of VBUS Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the VCONN Swap process. VCONN Shall be continually sourced during the VCONN Swap process to maintain power to the Cable Plug(s) i.e., make before break. Before communicating with a Cable Plug a Port Shall ensure that it is the VCONN Source and that the Cable Plugs are powered, by performing a VCONN Swap if necessary. Since it cannot be guaranteed that the present VCONN Source is supplying VCONN, the only means to ensure that the Cable Plugs are powered is for a Port wishing to communicate with a Cable Plug to become the VCONN Source. If a Not_Supported Message is returned in response to the VCONN_Swap Message, then the Port is allowed to become the VCONN Source until a Hard Reset or Detach. A VCONN Source that is also a Source can attempt to send a Discover Identity Command using SOP’ to a Cable Plug prior to the establishment of the First Explicit Contract. Note: Even when it is presently the VCONN Source, the Sink is not permitted to initiate an AMS with a Cable Plug unless Rp is set to SinkTxOK (see Section 6.9, "Accept, Reject and Wait"). 6.3.12 Wait Message The Wait Message is a Valid response to one of the following Messages:  It Shall be sent to signal the Sink, in response to a Request Message in SPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent to signal the Sink, in response to a EPR_Request Message in EPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is currently unable to do a Power Role Swap.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is currently unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source to indicate it is currently unable to do a VCONN Swap.  It Shall be sent by the recipient of an Enter_USB Message to indicate it is currently unable to enter the requested USB Mode. The Wait Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.9, "Accept, Reject and Wait"). 6.3.12.1 Wait in response to a Request Message The Wait Message allows the Source time to recover the power it requires to meet the request, e.g., through Re- negotiation with other Sinks or an upstream Source. A Source Should only send a Wait Message in response to a Request Message when an Explicit Contract exists between the Port Partners. The Sink is allowed to repeat the Request Message using the SinkRequestTimer and Shall ensure that there is tSinkRequest after receiving the Wait Message before sending another Request Message. 6.3.12.2 Wait in response to a PR_Swap Message The Wait Message is used when responding to a PR_Swap Message to indicate that a Power Role Swap might be possible in the future. This can occur in any case where the device receiving the PR_Swap Message needs to evaluate the request further e.g., by requesting Sink Capabilities from the originator of the PR_Swap Message. Once it has completed this evaluation one of the Port Partners Should initiate the Power Role Swap process again by sending a PR_Swap Message. The Wait Message is also used where a Hub is operating in hybrid mode when a request cannot be satisfied (see [UCSI]). Page 134 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A Port that receives a Wait Message in response to a PR_Swap Message Shall wait tPRSwapWait after receiving the Wait Message before sending another PR_Swap Message. 6.3.12.3 Wait in response to a DR_Swap Message The Wait Message is used when responding to a DR_Swap Message to indicate that a Data Role Swap might be possible in the future. This can occur in any case where the device receiving the DR_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the Data Role Swap process again by sending a DR_Swap Message. A Port that receives a Wait Message in response to a DR_Swap Message Shall wait tDRSwapWait after receiving the Wait Message before sending another DR_Swap Message. 6.3.12.4 Wait in response to a VCONN_Swap Message The Wait Message is used when responding to a VCONN_Swap Message to indicate that a VCONN_Swap might be possible in the future. This can occur in any case where the device receiving the VCONN_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the VCONN Swap process again by sending a VCONN_Swap Message. A Port that receives a Wait Message in response to a VCONN_Swap Message Shall wait tVCONNSwapWait after receiving the Wait Message before sending another VCONN_Swap Message. A Port that is currently the VCONN Source Shall respond with an Accept Message (rather than a Wait Message) if the Port Partner's Revision and Version, as reported in the Revision Message, is earlier than R3.2 V1.1. A Port Partner supporting an earlier Revision and Version will not expect a Wait Message and will generate a Soft Reset in response. 6.3.12.5 Wait in response to an Enter_USB Message The Wait Message is used, by the UFP, when responding to an Enter_USB Message to indicate that entering the requested USB Mode might be possible in the future. This can occur, for example, in any case where the UFP needs to Negotiate more power to enter the mode. Once the UFP has completed this the DFP Should initiate the Enter USB process again by sending an Enter_USB Message. A DFP that receives a Wait Message in response to an Enter_USB Message Shall wait tEnterUSBWait after receiving the Wait Message before sending another Enter_USB Message. 6.3.13 Soft Reset Message A Soft_Reset Message May be initiated by either the Source or Sink to its Port Partner requesting a Soft Reset. The Soft_Reset Message Shall cause a Soft Reset of the connected Port Pair (see Section 6.8.1, "Soft Reset and Protocol Error"). If the Soft_Reset Message fails a Hard Reset Shall be initiated within tHardReset of the last CRCReceiveTimer expiring after nRetryCount retries have been completed. A Soft_Reset Message is used to recover from Protocol Layer errors; putting the Message counters to a known state to regain Message synchronization. The Soft_Reset Message has no effect on the Source or Sink; that is the previously Negotiated direction. Voltage and current remain unchanged. Modal Operation is unaffected by Soft Reset. However after a Soft Reset has completed, an Explicit Contract Negotiation occurs, in order to re-establish PD Communication and to bring state operation for both Port Partners back to either the PE_SNK_Ready or PE_SRC_Ready states as appropriate (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams"). A Soft_Reset Message May be sent by either the Source or Sink when there is a Message synchronization error. If the error is not corrected by the Soft Reset, Hard Reset Signaling Shall be issued (see Section 6.8.3, "Hard Reset"). A Soft_Reset Message Shall be targeted at a specific entity depending on the type of SOP* Packet used. Soft_Reset Messages sent using SOP Packets Shall Soft Reset the Port Partner only. Soft_Reset Messages sent using SOP’ Packet/ SOP’’ Packets Shall Soft Reset the corresponding Cable Plug only. After a VCONN Swap the VCONN Source needs to reset the Cable Plug's Protocol Layer to ensure MessageID synchronization. If after a VCONN Swap the VCONN Source wants to communicate with a Cable Plug using SOP’ Packets, it Shall issue a Soft_Reset Message using a SOP’ Packet in order to reset the Cable Plug's Protocol Layer. If Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 135 the VCONN Source wants to communicate with a Cable Plug using SOP’’ Packets, it Shall issue a Soft_Reset Message using a SOP’’ Packet in order to reset the Cable Plug's Protocol Layer. 6.3.14 Data_Reset Message The Data_Reset Message May be sent by either the DFP or UFP and Shall reset the USB data connection and exit all Alternate Modes with its Port Partner while preserving the power on VBUS. USB4® Mode capable ports Shall support the Data_Reset Message and other ports May support the Data_Reset Message. The Data_Reset Message Shall Not change the existing:  Power Contract  Data Roles (i.e., which Port is the DFP or UFP) The receiver of the Data_Reset Message Shall respond by sending an Accept Message and then follow the process outlined in the following steps. Neither the sender nor receiver Shall initiate a VCONN Swap until the Data Reset process is complete, and the Data_Reset_Complete Message has been sent. Following receipt of the Accept Message, or GoodCRC following the Accept, depending which Port sends the Data_Reset Message: 1) The DFP Shall:  Disconnect the Port's [USB 2.0] D+/D- signals.  If operating in [USB 3.2] remove the Port's Rx Terminations (see [USB 3.2]).  If operating in [USB4] drive the Port's SBTX to a logic low (see [USB4]). 2) Both the DFP and UFP Shall exit all Alternate Modes if any. 3) Reset the cable:  If the VCONN Source Port is also the UFP, then it Shall run the UFP VCONN Power Cycle process de- scribed in Section 7.1.15.1, "UFP VCONN Power Cycle".  If the VCONN Source Port is also the DFP, then it Shall run the DFP VCONN Power Cycle process de- scribed in Section 7.1.15.2, "DFP VCONN Power Cycle".  The DFP Shall exit the VCONN Power Cycle process as the VCONN Source and be sourcing VCONN. 4) After tDataReset the DFP Shall:  Reconnect the [USB 2.0] D+/D- signals.  If the Port was operating in [USB 3.2] or [USB4] reapply the Port's Rx Terminations (see [USB 3.2]). 5) The Data Reset process is complete; the DFP Shall send a Data_Reset_Complete Message and enter the USB4® Discovery and Entry Flow (See [USB Type-C 2.4]). If the Initiator of the Data_Reset Message does not receive a Valid response within tSenderResponse it Shall enter the ErrorRecovery State. 6.3.15 Data_Reset_Complete Message The Data_Reset_Complete Message Shall be sent by the DFP to the UFP to indicate the completion of the Data Reset process (see Section 6.3.14, "Data_Reset Message"). 6.3.16 Not_Supported Message The Not_Supported Message Shall be sent by a Port or Cable Plug in response to any Message it does not support. Returning a Not_Supported Message is assumed in this specification and has not been called out explicitly except in Section 6.13, "Message Applicability" which defines cases where the Not_Supported Message is returned. Page 136 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3.17 Get_Source_Cap_Extended Message The Get_Source_Cap_Extended Message is sent by a Port to request additional information about a Port's Source Capabilities. The Port Shall respond by returning a Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message"). 6.3.18 Get_Status Message The Get_Status Message is sent by a Port using SOP to request the Port Partner's present status. The Port Partner Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). A Port that receives an Alert Message (see Section 6.4.6, "Alert Message") indicates that the Source or Sink's Status has changed and Should be re-read using a Get_Status Message. The Get_Status Message May also be sent to an Active Cable to get its present status using SOP’/SOP’’. The Active Cable Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). 6.3.19 FR_Swap Message The FR_Swap Message Shall be sent by the New Source within tFRSwapInit after it has detected a Fast Role Swap signal (see Section 5.8.6.3, "Fast Role Swap Detection" and Section 6.6.17.3, "tFRSwapInit"). The Fast Role Swap AMS is necessary to apply Rp to the New Source and Rd to the New Sink and to re-synchronize the state machines. The tFRSwapInit time Shall be measured from the time the Fast Role Swap Request has been sent for tFRSwapRx (max) until the last bit of the EOP of the FR_Swap Message has been transmitted by the PHY Layer. The recipient of the FR_Swap Message Shall respond by sending an Accept Message. After a successful Fast Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the Source Shall also reset its CapsCounter. This ensures that only the Cable Plug responds with a GoodCRC Message to the Discover Identity Command. Prior to the Fast Role Swap AMS, the New Source Shall have Rd asserted on the CC wire and the New Sink Shall have Rp asserted on the CC wire. Note: This is an incorrect assignment of Rp/Rd (since Rp follows the Source and Rd follows the Sink as defined in [USB Type-C 2.4]) that is corrected by the Fast Role Swap AMS. During the Fast Role Swap AMS, the New Source Shall change its CC wire resistor from Rd to Rp and the New Sink Shall change its CC wire resistor from Rp to Rd. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged during the Fast Role Swap process. The Initial Source Should avoid being the VCONN Source (by using the VCONN Swap process) whenever not actively communicating with the cable, since it is difficult for the Initial Source to maintain VCONN power during the Fast Role Swap process. Note: A Fast Role Swap is a "best effort" solution to a situation where a PDUSB Device has lost its external power. This process can occur at any time, even during an AMS in which case error handling such as Hard Reset or [USB Type-C 2.4] Error Recovery will be triggered. Note: During the Fast Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Fast Role Swap process, refer to:  Section 7.1.13, "Fast Role Swap"  Section 7.2.10, "Fast Role Swap"  Section 8.3.3.19.5, "Policy Engine in Source to Sink Fast Role Swap State Diagram"  Section 8.3.3.19.6, "Policy Engine in Sink to Source Fast Role Swap State Diagram" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 137  Section 9.1.2, "Mapping to USB Device States" for VBUS mapping to USB states. 6.3.20 Get_PPS_Status The Get_PPS_Status Message is sent by the Sink to request additional information about a Source's status. The Port Shall respond by returning a PPS_Status Message (see Section 6.5.10, "PPS_Status Message"). 6.3.21 Get_Country_Codes The Get_Country_Codes Message is sent by a Port to request the alpha-2 country codes its Port Partner supports as defined in [ISO 3166]. The Port Partner Shall respond by returning a Country_Codes Message (see Section 6.5.11, "Country_Codes Message"). 6.3.22 Get_Sink_Cap_Extended Message The Get_Sink_Cap_Extended (Get Sink Capabilities Extended) Message is sent by a Port to request additional information about a Port's Sink Capabilities. The Port Shall respond by returning a Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). 6.3.23 Get_Source_Info Message The Get_Source_Info Message is sent by a Port to request the type, maximum Capabilities and present Capabilities of the Port when it is operating as a Source. The Port Shall respond by returning the Source_Info Message (See Section 6.4.11, "Source_Info Message"). 6.3.24 Get_Revision Message The Get_Revision Message is sent by a Port using SOP to request the Revision and Version of the Power Delivery Specification its Port Partner supports. The Port Partner Shall respond by returning a Revision Message (See Section 6.4.12, "Revision Message"). The Get_Revision Message May also be sent to a Cable Plug to request the Revision and Version of the Power Delivery Specification it supports using SOP’/SOP’’. The Active Cable Shall respond by returning a Revision Message (see Section 6.4.12, "Revision Message"). Page 138 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4 Data Message A Data Message Shall consist of a Message Header and be followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is a non-zero value. There are many types of Data Objects used to compose Data Messages. Some examples are:  Power Data Object (PDO) used to expose a Source Port's power Capabilities or a Sink's power requirements.  Request Data Object (RDO) used by a Sink Port to Negotiate an Explicit Contract.  Vendor Data Object (VDO) used to convey vendor specific information.  BIST Data Object (BDO) used for PHY Layer compliance testing.  Battery Status Data Object (BSDO) used to convey Battery status information.  Alert Data Object (ADO) used to indicate events occurring on the Source or Sink. The type of Data Object being used in a Data Message is defined by the Message Header's Message Type field and is summarized in Table 6.6, "Data Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.6 Data Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0_0001 Source_Capabilities Source or Dual-Role Power See Section 6.4.1.5 SOP only 0_0010 Request Sink only See Section 6.4.2 SOP only 0_0011 BIST Tester, Source or Sink See Section 6.4.3 SOP* 0_0100 Sink_Capabilities Sink or Dual-Role Power See Section 6.4.2 SOP only 0_0101 Battery_Status Source or Sink See Section 6.4.5 SOP only 0_0110 Alert Source or Sink See Section 6.4.6 SOP only 0_0111 Get_Country_Info Source or Sink See Section 6.4.7 SOP only 0_1000 Enter_USB DFP See Section 6.4.8 SOP* 0_1001 EPR_Request Sink See Section 6.4.9 SOP only 0_1010 EPR_Mode Source or Sink See Section 6.4.10 SOP only 0_1011 Source_Info Source See Section 6.4.11 SOP only 0_1100 Revision Source, Sink or Cable Plug See Section 6.4.12 SOP* 0_1101…0 _1110 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0 1111 Vendor_Defined Source, Sink or Cable Plug See Section 6.4.4 SOP* 1_0000…1 _1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 139 6.4.1 Capabilities Message There are two distinct Capabilities Messages: one used while in SPR Mode and another while in EPR Mode. This section defines the Capabilities Messages specific to the SPR Mode and Section 6.5.15, "EPR Capabilities Message" defines the Capabilities Messages specific to the EPR Mode. 6.4.1.1 Power Data Objects Sections Section 6.4.1.5, "SPR Source Capabilities Message" and Section 7.1.3, "Types of Sources" describes the Power Data Objects (PDOs) used in the construction of a Capabilities Message for both SPR Mode and EPR Mode. There are three types of Power Data Objects. They contain additional information beyond that encoded in the Message Header to identify each of the three types of Power Data Objects:  Fixed Supply is used to expose well-regulated fixed voltage power supplies.  Variable Supply is used to expose very poorly regulated power supplies.  Battery Supply is used to expose batteries that can be directly connected to VBUS. There are three types of Augmented Power Data Objects:  SPR PPS is used to expose a power supply whose output voltage can be programmatically adjusted over the Advertised voltage range and limited by the Source to a programmable current limit.  SPR AVS and EPR AVS are used to expose a power supply whose output voltage can be adjusted over the Advertised voltage range but otherwise is equivalent to a Fixed Supply (AVS does not support a programmable current limit). Power Data Objects are also used to expose additional Capabilities that May be utilized, such as in the case of a Power Role Swap. A list of one or more Power Data Objects Shall be sent by the Source to convey its Capabilities. The Sink May then request one of these Capabilities by returning a Request Data Object that contains an index to a Power Data Object, to Negotiate a mutually agreeable Explicit Contract. Where Maximum and Minimum voltage and current values are given in PDOs these Shall be taken to be absolute values. The Source and Sink Shall Not Negotiate a power level that would allow the current to exceed the maximum current supported by their receptacles or the Attached plug (see [USB Type-C 2.4]). The Source Shall limit its offered Capabilities to the maximum current supported by its receptacle and Attached plug. A Sink Shall only make a request from any of the Capabilities offered by the Source. For further details see Section 4.4, "Cable Type Detection". Sources expose their power Capabilities by sending a Source_Capabilities Message. Sinks expose their power requirements by sending a Sink_Capabilities Message. Both are composed of several 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). Table 6.7 Power Data Object Bit(s) Description Value Parameter B31…30 00b Fixed Supply (Vmin = Vmax) 01b Battery 10b Variable Supply (non-Battery) 11b Augmented Power Data Object (APDO) B29…0 Specific Power Capabilities are described by the PDOs in the following sections. Page 140 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Augmented Power Data Object (APDO) is defined to allow support for more than the four PDO types by extending the Power Data Object field from 2 to 4 bits when the B31…B30 are 11b. The generic APDO structure is shown in Table 6.8, "Augmented Power Data Object". Table 6.8 Augmented Power Data Object Bit(s) Description Value Parameter B31…30 11b Augmented Power Data Object (APDO) B29…28 00b SPR PPS 01b EPR AVS 10b SPR AVS 11b Reserved B27…0 Specific Power Capabilities are described by the APDOs in the following sections. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 141 6.4.1.2 Source Power Data Objects This section lists the types of PDOs a Source can use in an SPR Capabilities or EPR Capabilities Message. 6.4.1.2.1 Fixed Supply Power Data Object Table 6.9, "Fixed Supply PDO – Source" describes the Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources"for the electrical requirements of the power supply. Since all USB Providers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29…23. All other Fixed Supply Power Data Objects Shall set bits 29…23 to zero. For a Source offering no Capabilities, the Voltage field (B19…10) Shall be set to 5V and theMaximum Current field Shall be set to 0mA. This is used in cases such as a Dual-Role Power device which offers no Capabilities in its default Power Role or when external power is required to offer power. When a Source wants a Sink, consuming power from VBUS, to go to its lowest power state, the Voltage field (B19…10) Shall be set to 5V and the Maximum Current field Shall be set to 0mA. This is used in cases where the Source wants the Sink to draw pSnkSusp. 6.4.1.2.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.2 USB Suspend Supported Prior to an Explicit Contract or when the USB Communications Capable bit is set to zero, the USB Suspend Supported flag is undefined and Sinks Shall follow the rules for suspend as defined in [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. After an Explicit Contract has been Negotiated:  If the USB Suspend Supported flag is set, then the Sink Shall follow the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and resume. A PDUSB Peripheral May draw up to pSnkSusp during suspend; a PDUSB Hub May draw up to pHubSusp during suspend (see Section 7.2.3, "Sink Standby"). Table 6.9 Fixed Supply PDO – Source Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ for Dual-Role Power device. B28 USB Suspend Supported Set to ‘1’ if USB suspend is supported. B27 Unconstrained Power Set to ‘1’ if unconstrained power is available. B26 USB Communications Capable Set to ‘1’ if capable of USB Communications capable B25 Dual-Role Data Set to ‘1’ for a Dual-Role Data device. B24 Unchunked Extended Messages Supported Set to ‘1 if Unchunked Extended Messages are supported. B23 EPR Capable Set to ‘1 if EPR Capable. B22 Reserved Reserved – Shall be set to zero. B21…20 Peak Current Peak Current value. B19…10 Voltage Voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 142 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the USB Suspend Supported flag is cleared, then the Sink Shall Not apply the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and May continue to draw the Negotiated power. Note: When USB is suspended, the USB device state is also suspended. Sinks May indicate to the Source that they would prefer to have the USB Suspend Supported flag cleared by setting the No USB Suspend flag in a Request Message (see Section 6.4.2.5, "No USB Suspend"). 6.4.1.2.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.2.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sources capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.2.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Data bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.1.2.1.7 EPR Mode Capable The EPR Capable bit is a Static bit that Shall be set if the Source is designed to supply more than 100W and operate in EPR Mode. When this bit is set, an EPR Source:  Operating in SPR Mode Shall only send an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Message  May only enter EPR Mode when the Cable and the Sink also report that they are EPR Capable. 6.4.1.2.1.8 Peak Current The USB Power Delivery Fixed Supply is only required to deliver the amount of current requested in the Operating Current field (IoC) of an RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current (see Section 7.2.8, "Sink Peak Current Operation") period needed to maintain such average power. The Peak Current field allows a Source to Advertise this additional capability. This capability is intended for direct Port to Port connections only and Shall Not be offered to downstream Sinks via a Hub. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 143 Every Fixed Supply PDO Shall contain a Peak Current field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current field in the corresponding Fixed Supply PDO (see Table 6.10, "Fixed Power Source Peak Current Capability"). Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding Fixed Supply PDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall also set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send the Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. 6.4.1.2.2 Variable Supply (non-Battery) Power Data Object Table 6.11, "Variable Supply (non-Battery) PDO – Source" describes a Variable Supply (non-Battery) (10b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall define the range that output voltage Shall fall within. This does not indicate the voltage that will be supplied, except it Shall fall within that range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. The Minimum Voltage field value Shall Not be less than 80% of the Maximum Voltage field value. 6.4.1.2.3 Battery Supply Power Data Object Table 6.12, "Battery Supply PDO – Source" describes a Battery Supply (01b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall represent the Battery's voltage range. The Battery Shall be capable of supplying the Power value over the entire voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: The Battery Supply PDO uses power instead of current. Table 6.10 Fixed Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Table 6.11 Variable Supply (non-Battery) PDO – Source Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 144 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Sink May monitor the Battery voltage. Table 6.12 Battery Supply PDO – Source Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Allowable Power Maximum allowable power in 250mW units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 145 6.4.1.2.4 Augmented Power Data Object (APDO) The voltage fields define the output voltage range over which the power supply Shall be adjustable in 20mV steps in SPR PPS Mode and 100mV steps in both SPR AVS Mode and EPR AVS Mode. The Maximum Current field contains the current the Programmable Power Supply Shall be capable of delivering over the Advertised voltage range. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. 6.4.1.2.4.1 SPR Programmable Power Supply APDO Table 6.13, "SPR Programmable Power Supply APDO – Source" below describes the SPR PPS (1100b) APDO for a Source operating in SPR Mode and supplying 5V up to 21V. The PPS APDO is used primarily for Sink Directed Charge Directed Charge of a Battery in the Sink. When applying a current to the Battery greater than the cable supports, a high efficiency fixed voltage scaler May be used in the Sink to reduce the cable current. 6.4.1.2.4.1.1 PPS Power Limited When the PPS Power Limited bit is set, the SPR PPS Source Shall operate in the same way as if the PPS Power Limited bit is clear (see Section 7.1.4.2, "SPR Programmable Power Supply (PPS)" with the below exception:  May supply power that exceeds the Source's rated PDP within the Optional operating area in Figure 7.7, "SPR PPS Constant Power". When the PPS Power Limited bit is cleared, the SPR PPS Source Shall deliver the Maximum Current field value up to the Maximum Voltage as Advertised in its APDO. The SPR PPS Source Shall Not reject an RDO with an Operating Current field value that is less than or equal to the Maximum Current field value in the APDO even if the requested Operating Current field value is greater than the Source's PDP/requested Output voltage. Table 6.13 SPR Programmable Power Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27 PPS Power Limited Set to ‘1’ when PPS Power Limited B26…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Page 146 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.2.4.2 SPR Adjustable Voltage Supply APDO Table 6.14, "SPR Adjustable Voltage Supply APDO – Source" below describes the SPR AVS (1110b) APDO for a Source operating in SPR Mode and supplying 9V up to 20V. 6.4.1.2.4.2.1 Peak Current The Peak Current field follows the same definition as for the Peak Current field (see Section 6.4.1.2.1.8, "Peak Current" and Table 6.10, "Fixed Power Source Peak Current Capability". 6.4.1.2.4.3 EPR Adjustable Voltage Supply APDO Table 6.15, "EPR Adjustable Voltage Supply APDO – Source" below describes the EPR AVS (1101b) APDO for a Source operating in EPR Mode and supplying 15V up to 48V. 6.4.1.2.4.3.1 PDP The PDP field Shall contain the AVS Port's PDP. See Section 10.2.3.3, "Optional Normative Extended Power Range (EPR)" and Figure 10.6, "Valid EPR AVS Operating Region" for more information regarding how PDP in the AVS APDO relates to maximum available current. 6.4.1.2.4.3.2 Peak Current The USB Power Delivery EPR AVS is only required to deliver the amount of current requested in the Operating Current field (IoC) of an AVS RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current period needed to maintain such average power (see Section 7.2.8, "Sink Peak Current Operation"). The Peak Current (Source EPR AVS) field allows a Source to Advertise this additional capability. This Table 6.14 SPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…26 Peak Current Peak Current (see Table 6.10, "Fixed Power Source Peak Current Capability")) B25…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the maximum voltage in the SPR AVS range is 15V. Table 6.15 EPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Peak Current (Source EPR AVS) Peak Current (see Table 6.16, "EPR AVS Power Source Peak Current Capability") B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 147 capability is intended for direct Port to Charger connections only and Shall Not be offered to downstream Sinks via a Hub. Every EPR AVS APDO Shall contain a Peak Current (Source EPR AVS) field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current (Source EPR AVS) field in the corresponding EPR AVS APDO (see Table 6.16, "EPR AVS Power Source Peak Current Capability". Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding EPR AVS APDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send a Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. Table 6.16 EPR AVS Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Page 148 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.3 Sink Power Data Objects This section lists the types of PDOs a Sink can use in an SPR or EPR Capabilities Message. 6.4.1.3.1 Sink Fixed Supply Power Data Object Table 6.17, "Fixed Supply PDO – Sink" describes the Sink Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Sink Shall set the Voltage field to its required voltage and the Operational Current field to its required operating current. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. Since all USB Consumers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29 through 20. All other Fixed Supply Power Data Objects Shall set bits 29…20 to zero. For a Sink requiring no power from the Source, the Voltage field Shall be set to 5V and the Operational Current field Shall be set to 0mA. 6.4.1.3.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.2 Higher Capability In the case that the Sink needs more than vSafe5V (e.g., 15V) to provide full functionality, then the Higher Capability bit Shall be set. 6.4.1.3.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. Table 6.17 Fixed Supply PDO – Sink Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ if Dual-Role Power supported B28 Higher Capability Set to ‘1’ if Higher Capability supported B27 Unconstrained Power Set to ‘1’ if Unconstrained Power supported B26 USB Communications Capable Set to ‘1’ if USB Communications Capable B25 Dual-Role Data Dual-Role Data B24...23 Fast Role Swap required USB Type-C Current Fast Role Swap required USB Type-C current (see also [USB Type-C 2.4]): Value Description 00b Fast Role Swap not supported (default) 01b Default USB Port 10b 1.5A@5V 11b 3.0A@5V B22...20 Reserved Reserved – Shall be set to zero. B19…10 Voltage Voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 149 To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.3.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sinks capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.3.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Dataa bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.6 Fast Role Swap USB Type-C Current The Fast Role Swap required USB Type-C Current field Shall indicate the current level the Sink will require after a Fast Role Swap has been performed. The Initial Source Shall Not transmit a Fast Role Swap Request if the Fast Role Swap required USB Type-C Current field is set to zero. Initially when the New Source applies vSafe5V it will have Rd asserted but Shall provide the USB Type-C current indicated by the New Sink in this field. If the New Source is not able to supply this level of current, it Shall Not perform a Fast Role Swap. When Rp is asserted by the New Source during the Fast Role Swap AMS (see Section 6.3.19, "FR_Swap Message"), the value of USB Type-C current indicated by Rp Shall be the same or greater than that indicated in the Fast Role Swap required USB Type-C Current field. 6.4.1.3.2 Variable Supply (non-Battery) Power Data Object Table 6.18, "Variable Supply (non-Battery) PDO – Sink" describes a Variable Supply (non-Battery) (10b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Current field Shall be set to the operational current that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.3 Battery Supply Power Data Object Table 6.19, "Battery Supply PDO – Sink" describes a Battery Supply (01b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. Table 6.18 Variable Supply (non-Battery) PDO – Sink Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Page 150 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Power field Shall be set to the operational power that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: Only the Battery Supply PDO uses power instead of current. Required operating power is defined as the amount of power a given device needs to be functional. This value could be the maximum power the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.4 Augmented Power Data Objects See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Maximum and Minimum voltage fields Shall be set to the output voltage range that the Sink requires to operate. 6.4.1.3.4.1 SPR Programmable Power Supply APDO Table 6.20, "SPR Programmable Power Supply APDO – Sink" below describes a SPR PPS APDO for a Sink operating in SPR Mode and consuming 21V or less. The Maximum Current field Shall be set to the maximum current the Sink requires over the voltage range. The maximum current is defined as the maximum amount of current the device needs to fully support its function (e.g., Sink Directed Charge). Table 6.19 Battery Supply PDO – Sink Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Power Operational Power in 250mW units Table 6.20 SPR Programmable Power Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 151 6.4.1.3.4.2 SPR Adjustable Voltage Supply APDO Table 6.21, "SPR Adjustable Voltage Supply APDO – Sink" below describes the SPR AVS (1110b) APDO for a Sink operating in SPR AVS Mode. The Maximum Current 15V/Maximum Current 20V fields in the SPR AVS APDO for the Sink is defined as the maximum current the device needs to fully support its function. 6.4.1.3.4.3 EPR Adjustable Voltage Supply APDO Table 6.22, "EPR Adjustable Voltage Supply APDO – Sink" below describes a EPR AVS APDO for a Sink operating in EPR AVS Mode. The PDP field in the EPR AVS APDO for the Sink is defined as the PDP the device needs to fully support its function. 6.4.1.4 SPR Capabilities Message Construction An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) Shall have at least one Power Data Object for vSafe5V. The SPR Capabilities Message Shall also contain the sending Port's information followed by up to 6 additional Power Data Objects. Power Data Objects in an SPR Capabilities Message Shall be sent in the following order: 1) The vSafe5V Fixed Supply PDO Shall always be the first (A)PDO. 2) The remaining Fixed Supply PDOs, if present, Shall be sent in voltage order; lowest to highest. 3) The Battery Supply PDOs if present Shall be sent in Minimum voltage order; lowest to highest. 4) The Variable Supply (non-Battery) PDOs, if present, Shall be sent in Minimum voltage order; lowest to highest. 5) The SPR AVS APDO, if present, Shall be sent. 6) The Programmable Power Supply APDOs, if present, Shall be sent in Maximum voltage order, lowest to highest. Note: The EPR Capabilities Message construction is defined in Section 6.5.15.1, "EPR Capabilities Message Construction". Table 6.21 SPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum Current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the Maximum voltage in the SPR AVS range is 15V. Table 6.22 EPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Reserved Reserved – Shall be set to zero. B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Page 152 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.12, "SPR Capabilities Message Construction" describes the construction of an SPR Capabilities Message. The Message will always have at least one Fixed Supply 5V PDO and may have up to six more PDOs depending on the Source Capabilities. Figure 6.12 SPR Capabilities Message Construction Figure 6.13 Example Capabilities Message with 2 Power Data Objects In the 27W Source as shown in Figure 6.13, "Example Capabilities Message with 2 Power Data Objects", the Number of Data Objects field is 2: vSafe5V plus one other voltage. Power Data Objects (PDO) and Augmented Power Data Objects (APDO) are identified by the Message Header's Message Type field. They are used to form SPR Capabilities Messages. 6.4.1.5 SPR Source Capabilities Message Sources send a Source_Capabilities Message either as part of advertising Port Capabilities, or in response to a Get_Source_Cap Message. See Section 6.5.15.2, "EPR_Source_Capabilities Message" for information about EPR Source Capabilities Messages. Following a Hard Reset, a power-on event or plug insertion event, a Source Port Shall send a Source_Capabilities Message after every SourceCapabilityTimer timeout as an Advertisements that Shall be interpreted by the Sink Port on Attachment. The Source Shall continue sending a minimum of nCapsCount Source_Capabilities Messages until a GoodCRC Message is received. Additionally, a Source_Capabilities Message Shall only be sent by a Port in the following cases:  By the Source Port from the PE_SRC_Ready state upon a change in its ability to supply power to this Port.  By a Source Port or Dual-Role Power Port in response to a Get_Source_Cap Message.  Optionally by a Source Port from the PE_SRC_Ready state when available power in a multi-Port system changes, even if the Source Capabilities for this Port have not changed. A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual- Role Power ports presently operating as a Sink. Each Power Data Object Shall describe a specific Source capability such as a Battery (e.g., 2.8-4.1V) or a Fixed Supply (e.g., 15V) at a maximum allowable current. The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sources Shall minimally offer one Power Data Object that reports vSafe5V. A Source Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Source capability and voltage. Header 2 bytes PDO 1 PDO 2 PDO 3 PDO 4 PDO 5 PDO 6 PDO 7 001b 010b 011b 100b 101b 110b 111b Header No. of Data Objects = 2 Fixed 5V PDO Fixed 9V PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 153 Sinks with Accessory Support do not source VBUS (see [USB Type-C 2.4]). Sinks with Accessory Support are still considered Sources when sourcing VCONN to an Accessory even though VBUS is not applied; in this case they Shall Advertise vSafe5V with the Maximum Current field set to 0mA in the first Power Data Object. The main purpose of this is to enable the Sink with Accessory Support to get into the PE_SRC_Ready State to enter an Alternate Mode. A Sink in SPR Mode Shall evaluate every Source_Capabilities Message it receives and Shall respond with a Request Message. If its power consumption exceeds the Source Capabilities it Shall Re-negotiate so as not to exceed the Source's most recently Advertised Capabilities. A Sink, in SPR Mode, in an Explicit Contract with a PPS APDO, Shall periodically re-request the PPS APDO at least every tPPSRequest until either:  The Sink requests something other than PPS APDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. A Sink in EPR Mode that receives a Source_Capabilities Message in response to a Get_Source_Cap Message Shall Not respond with a Request Message. If a Sink in EPR Mode receives a Source_Capabilities Message, not in response to a Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. A Source that has accepted a Request Message with a Programmable RDO Shall issue Hard Reset Signaling if it has not received a Request Message with a Programmable RDO within tPPSTimeout. The Source Shall discontinue this behavior after:  Receiving a Request Message with a Fixed Supply, Variable Supply or Battery Supply RDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. 6.4.1.6 SPR Sink Capabilities Message Sinks send a Sink_Capabilities Message (see Section 6.4.2, "Request Message") in response to a Get_Sink_Cap Message. See Section 6.5.15.3, "EPR_Sink_Capabilities Message" for more information about the Capabilities Message. A USB Power Delivery capable Sink, upon detecting vSafe5V on VBUS and after a SinkWaitCapTimer timeout without seeing a Source_Capabilities Message, Shall send a Hard Reset. If the Attached Source is USB Power Delivery capable, it responds by sending Source_Capabilities Messages thus allowing power Negotiations to begin. A Sink Port Shall report power levels it is able to operate at in a series of 32-bit Power Data Objects (see Section Table 6.7, "Power Data Object"). These are returned as part of a Sink_Capabilities Message in response to a Get_Sink_Cap Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). This is similar to that used for Source Port Capabilities with equivalent Power Data Objects for Fixed Supply, Variable Supply and Battery Supply as defined in this section. Power Data Objects are used to convey the Sink Port's operational power requirements including Dual-Role Power Ports presently operating as a Source. Each Power Data Object Shall describe a specific Sink operational power level, such as a Battery Supply (e.g., 2.8- 4.1V) or a Fixed Supply (e.g., 15V). The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sinks Shall minimally offer one Power Data Object with a power level at which the Sink can operate. A Sink Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Sink capability and voltage. All Sinks Shall include one Power Data Object that reports vSafe5V even if they require additional power to operate fully. In the case where additional power is required for full operation the Higher Capability bit Shall be set. Page 154 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.6.1 Use by Dual-Role Power devices Dual-Role Power devices send a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message") as part of advertising Port Capabilities when operating in Source role. Dual-Role Power devices send a Source_Capabilities Message in response to a Get_Source_Cap Message regardless of their present operating role. Similarly Dual-Role Power devices send a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message") in response to a Get_Sink_Cap Message regardless of their present operating role. 6.4.1.6.2 Management of the Power Reserve This section has been removed. Refer to Section 8.2.5, "Managing Power Requirements". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 155 6.4.2 Request Message A Request Message Shall be sent by a Sink to request power during the request phase of an SPR power Negotiation. The Request Data Object Shall be returned by the Sink making a request for power. It Shall be sent in response to the most recent Source_Capabilities Message (see Section 8.3.2.2, "Power Negotiation") when in SPR Mode. A Request Message Shall return one and only one Sink Request Data Object that Shall identify the Power Data Object being requested. The Source Shall respond to a Request Message with an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Request Message includes the requested power level. For example, if the Source_Capabilities Message includes a Fixed Supply PDO that offers 9V @ 1.5A and if the Sink only wants 9V @ 0.5A, it will set the Operating Current field to 50 (i.e., 10mA * 50 = 0.5A). The request uses a different format depending on the kind of power requested.  The Fixed Supply Power Data Object and Variable Supply Power Data Object share a common format shown in Table 6.23, "Fixed and Variable Request Data Object".  The Battery Supply Power Data Object uses the format shown in Table 6.24, "Battery Request Data Object".  The PPS Request Data Object's format is shown in Table 6.25, "PPS Request Data Object".  The AVS Request Data Object's format is shown in Table 6.26, "AVS Request Data Object". The Request Data Objects are also used by the EPR_Request Message when operating in EPR Mode. See Section 6.4.9, "EPR_Request Message" for information about the use of the EPR_Request Message. A Source operating in EPR Mode that receives a Request Message Shall initiate a Hard Reset. Table 6.23 Fixed and Variable Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0 - Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Current Operating current in 10mA units B9…0 Maximum Operating Current Maximum Operating current 10mA units Page 156 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.24 Battery Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0- Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Power Operating Power in 250mW units B9…0 Maximum Operating Power Maximum Operating Power in 250mW units Table 6.25 PPS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 20mV units. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Table 6.26 AVS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 25mV units, the least two significant bits Shall be set to zero making the effective voltage step size 100mV. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 157 6.4.2.1 Object Position The value in the Object Position field Shall indicate which object in the Source_Capabilities Message or EPR_Source_Capabilities Message the RDO refers to. The value 0001b always indicates the 5V Fixed Supply PDO as it is the first object following the Source_Capabilities Message’s Message Header or EPR_Source_Capabilities Message’s Extended Message Header. The number 0010b refers to the next PDO and so forth. The Object Position field values 0001b…0111b Shall only be used to refer to SPR (A)PDOs. SPR (A)PDOs May be requested by either a Request or an EPR_Request Message. Object positions 1000b…1011b Shall only be used to refer to EPR (A)PDOs. EPR (A)PDOs Shall only be requested by an EPR_Request Message. If the Object Position field in a Request Message contains a value greater than 0111b, the Source Shall send Hard Reset Signaling. 6.4.2.2 GiveBack Flag (Deprecated) The Giveback flag has been Deprecated and Shall be set to zero. 6.4.2.3 Capability Mismatch A Capabilities Mismatch occurs when the Source cannot satisfy the Sink's power requirements based on the Source Capabilities it has offered. In this case the Sink Shall make a Valid request from the offered Source Capabilities and Shall set the Capability Mismatch bit (see Section 8.2.5.2, "Power Capability Mismatch"). When a Capabilities Mismatch condition does not exist, the Sink Shall Not set the Capability Mismatch bit. When a Sink returns a Request Data Object with the Capability Mismatch bit set in response to a Source Capabilities Message, it indicates that it wants more power than the Source is currently offering. This can be due to either a specific voltage that is not being offered or there is not sufficient current for the voltages that are being offered. Sources whose Port Reported PDP is less than their Port Present PDP (see Section 6.4.11, "Source_Info Message") Shall respond to the Requests with the Capability Mismatch bit set as follows. The Source within tCapabilitiesMismatchResponse of the PS_RDY Message Shall send a new Source Capabilities Message that offers either: 1) The set of Source Capabilities to minimally satisfy the Sink's requirements based on what it actually requires for full operation by evaluating the: a) Sink_Capabilities_Extended Message(if supported by the Sink) and/or b) Sink_Capabilities or EPR_Sink_Capabilities Message. 2) The set of Source Capabilities the Source can supply at this time based on the Port Present PDP. To prevent looping, Sources Should Not send a new Source Capabilities Message in response to subsequent Request Message with the Capability Mismatch flag set until its Port Present PDP changes. Once a Guaranteed Capability Source that has responded to a Capability Mismatch, it Shall Not subsequently send out another Source Capabilities Message at a lower PDP unless the power required by the Sink (as indicated in its Sink Capabilities Message or Sink_Capabilities_Extended Message) has also been reduced. Sources wishing to manage their power May periodically check the Sink Capabilities Message or Sink_Capabilities_Extended Message to determine whether these have changed. Note: A Source Capabilities Message refers to a Source_Capabilities Message or an EPR_Source_Capabilities Message, and a Sink Capabilities Message refers to a Sink_Capabilities Message or EPR_Sink_Capabilities Message, Request refers to a Request Message or EPR_Request depending on operating mode. In this context a Valid Request Message means the following:  The Object Position field Shall contain a reference to an object that was present in the last received Source Capabilities Message.  The Operating Current/Operating Power field Shall contain a value which is less than or equal to the maximum current/power offered by the selected (A)PDO the Source Capabilities Message. Page 158 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.2.4 USB Communications Capable The USB Communications Capable flag Shall be set to one when the Sink has USB data lines and is capable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. The USB Communications Capable flag Shall be set to zero when the Sink does not have USB data lines or is otherwise incapable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. This is used by the Source to determine operation in certain cases such as USB suspend. If the USB Communications Capable flag has been set to zero by a Sink, then the Source needs to be aware that USB Suspend rules cannot be observed by the Sink. 6.4.2.5 No USB Suspend The No USB Suspend flag May be set by the Sink to indicate to the Source that this device is requesting to continue its Explicit Contract during USB Suspend. Sinks setting this flag typically have functionality that can use power for purposes other than USB Communication e.g., for charging a Battery. The Source uses this flag to evaluate whether it Should re-issue the Source_Capabilities Message with the USB Suspend Supported flag cleared. 6.4.2.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.2.7 EPR Mode Capable The EPR Capable bit Shall indicate whether or not the Sink is capable of operating in EPR Mode. When the Sink's ability to operate in EPR Mode changes, it Shall send a new Request Message with the updated EPR Capable bit set in the RDO. 6.4.2.8 Operating Current The Operating Current field in the Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. A new Request Message or EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The Operating Current field in the SPR Programmable Request Data Object is used in addition by the Sink to request the Source for the Current Limit level it needs. When the request is accepted the Source's output current supplied into any load Shall be less than or equal to the Operating Current value. When the Sink attempts to consume more current, the Source Shall reduce the output voltage so as not to exceed the Operating Current value. The Operating Current field in the AVS Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. Note: A Source in AVS Mode, unlike the SPR Source in PPS Mode, does not support current limit; the Sink is responsible not to take more current than it requested. A new Request / EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The value in the Operating Current field Shall Not exceed the value in the Maximum Current field of the Source_Capabilities Message. For EPR AVS, the Operating Current field Shall Not exceed the PDP / Output voltage rounded down to the nearest 50 mA. This field Shall apply to the Fixed Supply, Variable Supply, Programmable and AVS RDOs. 6.4.2.9 Maximum Operating Current The Maximum Operating Current field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Current field in the Request Message or EPR_Request Message, the field Shall be set equal to the value of the Operating Current field. To ensure backward compatibility, the Source Should Ignore this field. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 159 This field Shall apply to the Fixed Supply and Variable Supply RDO in SPR Mode and the Fixed Supply RDO in EPR Capable. 6.4.2.10 Operating Power The Operating Power field in the Request Data Object Shall be set to the highest power the Sink will draw throughout the Explicit Contract. This field Shall apply to the Battery Supply RDO. 6.4.2.11 Maximum Operating Power The Maximum Operating Power field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Power field in the Request Message, the field Shall be set equal to the value of the Operating Power field. To ensure backward compatibility, the Source Should Ignore this field. This field Shall apply to the Battery Supply RDO. 6.4.2.12 Output Voltage The Output Voltage field in the Programmable and AVS Request Data Objects Shall be set by the Sink to the voltage the Sink requires as measured at the Source's output connector. The Output Voltage field Shall be greater than or equal to the Minimum Voltage field and less than or equal to the Maximum Voltage field in the Programmable Power Supply and AVS APDOs, respectively. This field Shall apply to the Programmable RDO and AVS RDO. 6.4.3 BIST Message The BIST Message is sent to request the Port to enter a PHY Layer test mode (see Section 5.9, "Built in Self-Test (BIST)") that performs one of the following functions:  Enter a Continuous BIST Mode to send a continuous stream of test data to the Tester.  Enter and leave a Shared Capacity Group test mode. The Message format is as shown in Figure 6.14, "BIST Message". Figure 6.14 BIST Message All Ports Shall be able to be a Unit Under Test (UUT) only when operating at vSafe5V. All of the following BIST Modes Shall be supported:  Process reception of a BIST Carrier Mode BIST Data Object that Shall result in the generation of the appropriate carrier signal.  Process reception of a BIST Test Data BIST Data Object that Shall result in the Message being Ignored. UUTs with Ports constituting a Shared Capacity Group (see [USB Type-C 2.4]) Shall support the following BIST Mode:  Process reception of a BIST Shared Test Mode Entry BIST Data Object that Shall cause the UUT to enter BIST Shared Capacity Test Mode; a mode in which the UUT offers its full Source Capabilities on every Port in the Shared Capacity Group. Header No. of Data Objects = 1 or 7 BIST Data Object Page 160 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Process reception of a BIST Shared Test Mode Exit BIST Data Object that Shall cause the UUT to exit the BIST Shared Capacity Test Mode. When a Port receives a BIST Message BIST Data Object for a BIST Mode when not operating at vSafe5V, the BIST Message Shall be Ignored. When a Port receives a BIST Message BIST Data Object for a BIST Mode it does not support the BIST Message Shall be Ignored. When a Port or Cable Plug receives a BIST Message BIST Data Object for a Continuous BIST Mode the Port or Cable Plug enters the requested BIST Mode and Shall remain in that BIST Mode for tBISTContMode and then Shall return to normal operation (see Section 6.6.7.2, "BISTContModeTimer"). The usage model of the PHY Layer BIST Modes generally assumes that some controlling agent will request a test of its Port Partner. In Section 8.3.2.15, "Built in Self-Test (BIST)" there is a sequence description of the test sequences used for compliance testing. The fields in the BIST Data Object are defined in the Table 6.27, "BIST Data Object". 6.4.3.1 BIST Carrier Mode Upon receipt of a BIST Message, with a BIST Carrier Mode BIST Data Object, the UUT Shall send out a continuous string of BMC encoded alternating "1"s and "0"s. The UUT Shall exit the Continuous BIST Mode within tBISTContMode of this Continuous BIST Mode being enabled (see Section 6.6.7.2, "BISTContModeTimer"). 6.4.3.2 BIST Test Data Mode Upon receipt of a BIST Message, with a BIST Test Data BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter BIST Test Data Mode in which it sends no further Messages except for GoodCRC Messages in response to received Messages. See Section 5.9.2, "BIST Test Data Mode" for the definition of the Test Frame. The test Shall be ended by sending Hard Reset Signaling to reset the UUT. Table 6.27 BIST Data Object Bit(s) Value Parameter Description Reference Applicability B31…28 0000b…0100b Reserved Shall Not be used Section 1.4.2 - 0101b BIST Carrier Mode Request Transmitter to enter BIST Carrier Mode Section 6.4.3.1 Mandatory 0110b…0111b Reserved Shall Not be used Section 1.4.2 - 1000b BIST Test Data Sends a Test Frame. Section 6.4.3.2 Mandatory 1001b BIST Shared Test Mode Entry Requests UUT to enter BIST Shared Capacity Test Mode. Section 6.4.3.3.1 Mandatory for UUTs with shared capacity 1010b BIST Shared Test Mode Exit Requests UUT to exit BIST Shared Capacity Test Mode. Section 6.4.3.3.2 Mandatory for UUTs with shared capacity 1011b…1111b Reserved Shall Not be used Section 1.4.2 - B27…0 Reserved Shall be set to zero. Section 1.4.2 - Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 161 6.4.3.3 BIST Shared Capacity Test Mode A Shared Capacity Group of Ports share a common power source that is not capable of simultaneously powering all the ports to their full Source Capabilities (see [USB Type-C 2.4]). The BIST Shared Capacity Test Mode Shall only be implemented by ports in a Shared Capacity Group. The UUT Shared Capacity Group of Ports Shall contain one or more Ports, designated as Master Ports, that recognize both the BIST Shared Test Mode Entry BIST Data Object and the BIST Shared Test Mode Exit BIST Data Object. 6.4.3.3.1 BIST Shared Test Mode Entry When any master Port in a Shared Capacity Group receives a BIST Message with a BIST Shared Test Mode Entry BIST Data Object, while in the PE_SRC_Ready State, the UUT Shall enter a compliance test mode where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. Ports in the Shared Capacity Group that are not Master Ports Shall Not enter compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Upon receipt of a BIST Message, with a BIST Shared Test Mode Entry BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter the BIST Shared Capacity Test Mode. On entering this mode, the UUT Shall send a new Source_Capabilities Message from each Port in the Shared Capacity Group within tBISTSharedTestMode. The Tester will not exceed the shared capacity during this mode. 6.4.3.3.2 BIST Shared Test Mode Exit Upon receipt of a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, the UUT Shall return a GoodCRC Message and Shall exit the BIST Shared Capacity Test Mode. If any other Message, aside from a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, is received while in BIST Shared Capacity Test Mode this Shall Not cause the UUT to exit the BIST Shared Capacity Test Mode On exiting the mode, the UUT May send a new Source_Capabilities Message to each Port in the Shared Capacity Group or the UUT May perform ErrorRecovery on each Port. Ports in the Shared Capacity Group that are not Master Ports Shall Not exit compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Ports in the Shared Capacity Group that are not Master Ports Should Not exit compliance mode on receiving the BIST Shared Test Mode Exit BIST Data Object.  The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off.  The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs:  Hard Reset  Cable Reset  Soft Reset  Data Role Swap  Power Role Swap  Fast Role Swap  VCONN Swap.  The UUT May leave BIST Shared Capacity Test Mode if the Tester makes a request that exceeds the Capabilities of the UUT. Page 162 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4 Vendor Defined Message The Vendor_Defined Message (VDM) is provided to allow vendors to exchange information outside of that defined by this specification. A Vendor_Defined Message Shall consist of at least one Vendor Data Object (VDO), the VDM Header, and May contain up to a maximum of six additional VDOs. To ensure vendor uniqueness of Vendor_Defined Messages, all Vendor_Defined Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. Two types of Vendor_Defined Messages are defined: Structured VDMs and Unstructured VDMs. A Structured VDM defines an extensible structure designed to support Modal Operation. An Unstructured VDM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. The Message format Shall be as shown in Figure 6.15, "Vendor Defined Message". Figure 6.15 Vendor Defined Message The VDM Header Shall be the first 4-byte object in a Vendor Defined Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. Additionally, vendors May make use of the Commands in a Structured VDM. The fields in the VDM Header for an Unstructured VDM, when the VDM Type Bit is set to zero, Shall be as defined in Table 6.28, "Unstructured VDM Header". The fields in the VDM Header for a Structured VDM, when the VDM Type Bit is set to one Shall be as defined in Table 6.29, "Structured VDM Header". Both Unstructured VDMs and Structured VDMs Shall only be sent and received after an Explicit Contract has been established. The only exception to this is the Discover Identity Command which May be sent by Source when a Default Contract or an Implicit Contract (in place after Attach, a Power Role Swap or Fast Role Swap) is in place in order to discover Cable Capabilities (see SSection 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 6.4.4.1 Unstructured VDM The Unstructured VDM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the VID. The Port Partners and Cable Plugs Shall exit any states entered using an Unstructured VDM when a Hard Reset appears on PD. The following rules apply to the use of Unstructured VDM Messages:  Unstructured VDMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract Unstructured VDMs Shall Not be sent and Shall be Ignored if received.  Only the DFP Shall be an Initiator of Unstructured VDMs.  Only the UFP or a Cable Plug Shall be a Responder to Unstructured VDM.  Unstructured VDMs Shall Not be initiated or responded to under any other circumstances. Header No. of Data Objects = 1-7 VDM Header 0-6 VDOs Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 163  Unstructured VDMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can Unstructured VDMs be sent or received. The Active Mode and the associated Unstructured VDMs Shall use the same SVID.  Unstructured VDMs May be used with SOP* Packets.  When a DFP or UFP does not support Unstructured VDMs or does not recognize the VID it Shall return a Not_Supported Message. Table 6.28, "Unstructured VDM Header" illustrates the VDM Header bits. 6.4.4.1.1 USB Vendor ID The Vendor ID (VID) field Shall contain the 16-bit Vendor ID value assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. 6.4.4.1.2 VDM Type The VDM Type field Shall be set to zero indicating that this is an Unstructured VDM. 6.4.4.2 Structured VDM Setting the VDM Type field to 1 (Structured VDM) defines the use of bits B14…0 in the Structured VDM Header. The fields in the Structured VDM Header are defined in Table 6.29, "Structured VDM Header". The following rules apply to the use of Structured VDM Messages:  Structured VDMs Shall only be used when an Explicit Contract is in place with the following exception:  Prior to establishing the First Explicit Contract, a Source May issue Discover Identity Messages, to a Cable Plug using SOP’ Packets, as an Initiator (see Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram").  Either Port May be an Initiator of Structured VDMs except for the Enter Mode and Exit Mode Commands which Shall only be initiated by the DFP.  A Cable Plug Shall only be a Responder to Structured VDMs.  Structured VDMs Shall Not be initiated or responded to under any other circumstances.  When a DFP or UFP does not support Structured VDMs any Structured VDMs received Shall return a Not_Supported Message.  When using any of the SVID Specific Commands in the Structured VDM Header (VDM Header b4…0 - value 16 - 31) the Responder Shall NAK Messages where the SVID in the VDM Header is not recognized as an SVID that uses SVID Specific Commands or the use of SVID Specific Commands is not supported for the SVID.  When a Cable Plug does not support Structured VDMs any Structured VDMs received Shall be Ignored. Table 6.28 Unstructured VDM Header Bit(s) Parameter Description B31…16 Vendor ID (VID) Unique 16-bit unsigned integer. Assigned by the USB-IF to the Vendor. B15 VDM Type 0 = Unstructured VDM B14…0 Available for Vendor Use Content of this field is defined by the vendor. Page 164 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A DFP, UFP or Cable Plug which supports Structured VDMs and receiving a Structured VDM for a SVID that it does not recognize Shall reply with a NAK Command. Table 6.29 Structured VDM Header Bit(s) Field Description B31…16 Standard or Vendor ID (SVID) Unique 16-bit unsigned integer, assigned by the USB-IF B15 VDM Type 1 = Structured VDM B14…13 Structured VDM Version (Major) Version Number (Major) of the Structured VDM (not this specification Version):  Version 1.0 = 00b (Deprecated and Shall Not be used)  Version 2.x = 01b  Values 2-3 are Reserved and Shall Not be used B12…11 Structured VDM Version (Minor) For Commands 0…15 Version Number (Minor) of the Structured VDM  Version 2.0 = 00b (Used for ports implemented prior to USB PD Revision 3.1, Version 1.6)  Version 2.1 = 01b (Used for ports implemented starting with USB PD Revision 3.1, Version 1.6)  All other Values are Reserved and Shall Not be used  SVID Specific Commands (16…31) defined by the SVID. B10…8 Object Position For the Enter Mode, Exit Mode, and Attention Commands (Requests/ Responses):  000b = Reserved and Shall Not be used.  001b…110b = Index into the list of VDOs to identify the desired Alternate Mode VDO  111b = Exit all Active Modes (equivalent of a power on reset). Shall  only be used with the Command. Commands 0…3, 7…15:  000b  001b…111b = Reserved and Shall Not be used. SVID Specific Commands (16…31) defined by the SVID. B7…6 Command Type 00b = REQ (Request from Initiator Port) 01b = ACK (Acknowledge Response from Responder Port) 10b = NAK (Negative Acknowledge Response from Responder Port) 11b = BUSY (Busy Response from Responder Port) B5 Reserved Shall be set to zero and Shall be Ignored B4…01 Command 0 = Reserved and Shall Not be used. 1 = Discover Identity 2 = Discover SVIDs 3 = Discover Modes 4 = Enter Mode 5 = Exit Mode 6 = Attention 7-15 = Reserved and Shall Not be used. 16…31 = SVID Specific Commands 1) In the case where a SID is used the modes are defined by a standard. When a VID is used the modes are defined by the Vendor. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 165 Section Table 6.30, "Structured VDM Commands" shows the Commands, which SVID to use with each Command and the SOP* values which Shall be used. 6.4.4.2.1 SVID The Standard or Vendor ID (SVID) field Shall contain either a 16-bit USB Standard ID value (SID) or the 16-bit assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. Section Table 6.31, "SVID Values" lists specific SVID values referenced by this specification. 6.4.4.2.2 VDM Type The VDM Type field Shall be set to one indicating that this is a Structured VDM. 6.4.4.2.3 Structured VDM Version The Structured VDM Version (Major)/Structured VDM Version (Minor) fields indicate the level of functionality supported in the Structured VDM part of the specification. This is not the same Version as the Version of this specification. The Structured VDM Version (Major) Shall be set to 01b to indicate Version 2.x with the Structured VDM Version (Minor) field set as appropriate based on whether the Port is implemented to USB PD Revision 3.1, Version 1.6 (or newer) or a prior Version. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every Structured VDM Version number starting from Version 1.0. On receipt of a VDM Header with a higher Version number than it supports, a Port or Cable Plug Shall respond using the highest Version number it supports. On receipt of a VDM Header with a lower Version number than it supports, a Port or Cable Plug Shall respond using the same Version number it received. The Structured VDM Version (Major)/Structured VDM Version (Minor) fields of the Discover Identity Command sent and received during the Discovery Process Shall be used to determine the lowest common Structured VDM Version supported by the Port Partners or Cable Plug and Shall continue to operate using this Specification Revision until they are Detached. After discovering the Structured VDM Version, the Structured VDM Version (Major)/ Structured VDM Version (Minor) fields Shall match the agreed common Structured VDM Version. Table 6.30 Structured VDM Commands Command VDM Header SVID Field SOP* used Discover Identity Shall only use the PD SID. Shall only use SOP/SOP’. Discover SVIDs Shall only use the PD SID. Shall only use SOP/SOP’. Discover Modes Valid with any SVID. Shall only use SOP/SOP’. Enter Mode Valid with any SVID. Valid with SOP*. Exit Mode Valid with any SVID. Valid with SOP*. Attention Valid with any SVID. Valid with SOP*. SVID Specific Commands Valid with any SVID. Valid with SOP* (defined by SVID). Table 6.31 SVID Values Parameter Value Description PD SID 0xFF00 Standard ID allocated to this specification by USB-IF. DPTC SID 0xFF01 Standard ID allocated to [DPTC2.1] by USB-IF. Page 166 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.2.4 Object Position The Object Position field Shall be used by the Enter Mode and Exit Mode Commands. The Discover Modes Command returns a list of zero to six VDOs, each of which describes an Alternate Mode. The value in Object Position field is an index into that list that indicates which VDO (e.g., Alternate Mode) in the list the Enter Mode and Exit Mode Command refers to. The Object Position Shall start with one for the first Alternate Mode in the list. If the SVID is a VID, the content of the VDO for the Alternate Mode Shall be defined by the vendor. If the Standard or Vendor ID (SVID) is a SID, the value Shall be assigned, by the USB-IF, to the given Standard. The VDO's content May be as simple as a numeric value or as complex as bit mapped description of Capabilities of the Alternate Mode. In all cases, the Responder is responsible for deciphering the contents to know whether or not it supports the Alternate Mode at the Object Position. This field Shall be set to zero in the Request or Response (REQ, ACK, NAK or BUSY) when not required by the specification of the individual Command. 6.4.4.2.5 Command Type 6.4.4.2.5.1 Commands other than Attention This Command Type field Shall be used to indicate the type of Command request/response being sent. An Initiator Shall set the Command Type field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then the responses are as follows:  "Responder ACK" is the normal return and Shall be sent to indicate that the Command request was received and handled normally.  "Responder NAK" Shall be returned when the Command request:  Has an Invalid parameter (e.g., Invalid SVID or Alternate Mode).  Cannot be acted upon because the configuration is not correct (e.g., an Alternate Mode which has a dependency on another Alternate Mode or a request to exit an Alternate Mode which is not anActive Mode).  Is an Unrecognized Message.  The handling of "Responder NAK" is left up to the Initiator.  "Responder BUSY" Shall be sent in the response to a VDM when the Responder is unable to respond to the Command request immediately, but the Command request May be retried. The Initiator Shall wait tVDMBusy after a "Responder BUSY" response is received before retrying the Command request. 6.4.4.2.5.2 Attention Command This Command Type field Shall be used to indicate the type of Command request being sent. An Initiator Shall set the field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then no response Shall be made to an Attention Command. 6.4.4.2.6 Command 6.4.4.2.6.1 Commands other than Attention The Command field contains the value for the VDM Command being sent. The Commands explicitly listed in the Command field are used to identify devices and manage their operational Modes. There is a further range of Command values left for the vendor to use to manage additional extensions. A Structured VDM Command consists of a Command request and a Command response (ACK, NAK or BUSY). A Structured VDM Command is deemed to be completed (and if applicable, the transition to the requested functionality is made) when the GoodCRC Message has been successfully received by the Responder in reply to its Command response. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 167 If Structured VDMs are supported, but the Structured VDM Command request is an Unrecognized Message, it Shall be NAKed (see Table 6.32, "Commands and Responses"). 6.4.4.2.6.2 Attention Command The Command field contains the value for the VDM Command being sent (Attention). The Attention Command May be used by the Initiator to notify the Responder that it requires service. A Structured VDM Attention Command consists of a Command request but no Command response. A Structured VDM Attention Command is deemed to be completed when the GoodCRC Message has been successfully received by the Initiator in reply to its Attention Command request. If Structured VDMs are supported, but the Structured VDM Attention Command request is an Unrecognized Message it Shall be Ignored (see Table 6.32, "Commands and Responses"). 6.4.4.3 Use of Commands The VDM Header for a Structured VDM Message defines Commands used to retrieve a list of SVIDs the device supports, to discover the Modes associated with each SVID, and to enter/exit the Modes. The Commands include:  Discover Identity  Discover SVIDs  Discover Modes  Enter Mode  Exit Mode  Attention Additional Command space is also Reserved for Standard and Vendor use and for future extensions. The Command AMSs use the terms Initiator and Responder to identify messaging roles the ports are taking on relative to each other. This role is independent of the Port's power capability (Provider, Consumer etc.) or its present Power Role (Source or Sink). The Initiator is the Port sending the initial Command request and the Responder is the Port replying with the Command response. See Section 6.4.4.4, "Command Processes". All Ports that support Modes Shall support the Discover Identity, Discover SVIDs, the Discover Modes, the Enter Mode and Exit Mode Commands. Table 6.32, "Commands and Responses" details the responses a Responder May issue to each Command request. Responses not listed for a given Command Shall Not be sent by a Responder. A NAK response Should be taken as an indication not to retry that particular Command. Examples of Command usage can be found in Appendix C, "VDM Command Examples". Table 6.32 Commands and Responses Command Allowed Response Reference Discover Identity ACK, NAK, BUSY Section 6.4.4.3.1 Discover SVIDs ACK, NAK, BUSY Section 6.4.4.3.2 Discover Modes ACK, NAK, BUSY Section 6.4.4.3.3 Enter Mode ACK, NAK Section 6.4.4.3.4 Exit Mode ACK, NAK Section 6.4.4.3.5 Attention None Section 6.4.4.3.6 Page 168 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1 Discover Identity The Discover Identity Command is provided to enable an Initiator to identify its Port Partner and for an Initiator (VCONN Source) to identify the Responder (Cable Plug or VPD). The Discover Identity Command is also used to determine whether a Cable Plug or VPD is PD-Capable by looking for a GoodCRC Message Response. The Discover Identity Command Shall only be sent to SOP when there is an Explicit Contract. The Discover Identity Command Shall be used to determine whether a given Cable Plug or VPD is PD Capable (see Section 8.3.3.21.1, "Initiator Structured VDM Discover Identity State Diagram" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). In this case a Discover Identity Command request sent to SOP’ Shall Not cause a Soft Reset if a GoodCRC Message response is not returned since this can indicate a non-PD Capable cable or VPD. Note: A Cable Plug or VPD will not be ready for PD Communication until tVCONNStable after VCONN has been applied (see [USB Type-C 2.4]). During Cable Plug or VPD discovery, when there is an Explicit Contract, Discover Identity Commands are sent at a rate defined by the DiscoverIdentityTimer (see Section 6.6.15, "DiscoverIdentityTimer") up to a maximum of nDiscoverIdentityCount times (see Section 6.7.5, "Discover Identity Counter"). A PD-Capable Cable Plug or VPD Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP’. The Discover Identity Command Shall be used to determine the identity and/or Capabilities of the Port Partner. The following products Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP:  A PD-Capable UFP that supports Modal Operation.  A PD-Capable product that has multiple DFPs.  A PD-Capable [USB4] product. The SVID in the Discover Identity Command request Shall be set to the PD SID (see Section Table 6.31, "SVID Values"). The Number of Data Objects field in the Message Header in the Discover Identity Command request Shall be set to 1 since the Discover Identity Command request Shall Not contain any VDOs. The Discover Identity Command ACK sent back by the Responder Shall contain an ID Header VDO, a Cert Stat VDO, a Product VDO and the Product Type VDOs defined by the Product Type as shown in Figure 6.16, "Discover Identity Command response". This specification defines the following Product Type VDOs:  Passive Cable VDO (see Section 6.4.4.3.1.6, "Passive Cable VDO")  Active Cable VDOs (see Section 6.4.4.3.1.7, "Active Cable VDOs")  VCONN Powered USB Device (VPD) VDO (see Section 6.4.4.3.1.9, "VCONN Powered USB Device VDO")  UFP VDO (see Section 6.4.4.3.1.4, "UFP VDO")  DFP VDO (see Section 6.4.4.3.1.5, "DFP VDO") No VDOs other than those defined in this specification Shall be sent as part of the Discover Identity Command response. Where there is no Product Type VDO defined for a specific Product Type, no VDOs Shall be sent as part of the Discover Identity Command response. Any additional VDOs received by the Initiator Shall be Ignored. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 169 Figure 6.16 Discover Identity Command response The Number of Data Objects field in the Message Header in the Discover Identity Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the product is a DRD both a Product Type (UFP) and a Product Type (DFP) are declared in the ID Header. These products Shall return Product Type VDOs for both UFP and DFP beginning with the UFP VDO, then by a 32-bit Pad Object (defined as all '0's), followed by the DFP VDO as shown in Figure 6.17, "Discover Identity Command response for a DRD". Figure 6.17 Discover Identity Command response for a DRD 6.4.4.3.1.1 ID Header VDO The ID Header VDO contains information corresponding to the Power Delivery Product. The fields in the ID Header VDO Shall be as defined in Section Table 6.33, "ID Header VDO". Table 6.33 ID Header VDO Bit(s) Description Reference B31 USB Communications Capable as USB Host Section 6.4.4.3.1.1.1  Shall be set to one if the product is capable of enumerating USB Devices.  Shall be set to zero otherwise. B30 USB Communications Capable as a USB Device Section 6.4.4.3.1.1.2  Shall be set to one if the product is capable of being enumerated as a USB Device.  Shall be set to zero otherwise B29…27 SOP Product Type (UFP) Section 6.4.4.3.1.1.3  000b – Not a UFP  001b – PDUSB Hub  010b – PDUSB Peripheral  011b – PSD  100b…111b – Reserved, Shall Not be used. SOP’ Product Type (Cable Plug/VPD)  000b – Not a Cable Plug/VPD  001b…010b – Reserved, Shall Not be used.  011b – Passive Cable  100b – Active Cable  101b – Reserved, Shall Not be used.  110b – VCONN Powered USB Device (VPD)  111b – Reserved, Shall Not be used. Header No. of Data Objects = 4-71 VDM Header ID Header VDO Cert Stat VDO 0..32 Product Type VDO(s) Product VDO 1. Only Data objects defined in this specification can be sent as part of the Discover Identity Command. 2. The following sections define the number and content of the VDOs for each Product Type. Header No. of Data Objects = 7 VDM Header ID Header VDO Cert Stat VDO Product VDO Product Type VDO(s) yp ( ) UFP Pad DFP Page 170 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.1 USB Communications Capable as a USB Host The USB Communications Capable as USB Host field is used to indicate whether or not the Port has a USB Host Capability. 6.4.4.3.1.1.2 USB Communications Capable as a USB Device The USB Communications Capable as a USB Device field is used to indicate whether or not the Port has a USB Device Capability. 6.4.4.3.1.1.3 Product Type (UFP) The SOP Product Type (UFP) field indicates the type of Product when in UFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP Product Type (UFP) field Shall be the closest categorization of the main functionality of the Product in UFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in UFP role regardless of the present Data Role. Table 6.34, "Product Types (UFP)" defines the Product Type VDOs which Shall be returned. B26 Modal Operation Supported Section 6.4.4.3.1.1.4  Shall be set to one if the product (UFP/Cable Plug) is capable of supporting Modal Operation (Alternate Modes).  Shall be set to zero otherwise. B25…23 SOP - Product Type (DFP) Section 6.4.4.3.1.1.6  000b – Not a DFP  001b – PDUSB Hub  010b – PDUSB Host  011b – Power Brick  100b…111b – Reserved, Shall Not be used. SOP’: Reserved, Shall Not be used. B22…21 Connector Type Section 6.4.4.3.1.1.7  00b – Reserved, for compatibility with legacy systems.  01b – Reserved, Shall Not be used.  10b – USB Type-C Receptacle  11b – USB Type-C Plug B20…16 Reserved, Shall Not be used. B15…0 USB Vendor ID Section 6.4.4.3.1.1.8 [USB 2.0]/[USB 3.2]/[USB4] Table 6.34 Product Types (UFP) Product Type Description Product Type VDO Reference Undefined Shall be used when this is not a UFP. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PDUSB Peripheral Shall be used when the Product is a PDUSB Device other than a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PSD Shall be used when the Product is a PSD, e.g., power bank. None Table 6.33 ID Header VDO (Continued) Bit(s) Description Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 171 6.4.4.3.1.1.4 Product Type (Cable Plug) The SOP’ Product Type (Cable Plug/VPD) field indicates the type of Product when the Product is a Cable Plug or VPD, whether a VDO will be returned and if so the type of VDO to be returned. Table 6.35, "Product Types (Cable Plug/ VPD)" defines the Product Type VDOs which Shall be returned. 6.4.4.3.1.1.5 Modal Operation Supported The Modal Operation Supported bit is used to indicate whether or not the Product (either a Cable Plug or a device that can operate in the UFP role) is capable of supporting Modes. The Modal Operation Supported bit does not describe a DFP's Alternate Mode Controller functionality. A product that supports Modal Operation Shall respond to the Discover SVIDs Command with a list of SVIDs for all of the Modes it is capable of supporting whether or not those Modes can currently be entered. 6.4.4.3.1.1.6 Product Type (DFP) The SOP - Product Type (DFP) field indicates the type of Product when in DFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP - Product Type (DFP) field Shall be the closest categorization of the main functionality of the Product in DFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in DFP role regardless of the present Data Role. Table 6.36, "Product Types (DFP)" defines the Product Type VDOs which Shall be returned. In SOP’ Communication (Cable Plugs and VPDs) this bit field is Reserved and Shall be set to zero. 6.4.4.3.1.1.7 Connector Type Field The Connector Type field (B22…21) Shall contain a value identifying it as either a USB Type-C receptacle or a USB Type-C plug. Table 6.35 Product Types (Cable Plug/VPD) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None Active Cable Shall be used when the Product is a cable that incorporates signal conditioning circuits. Active Cable VDO Section 6.4.4.3.1.7 Passive Cable Shall be used when the Product is a cable that does not incorporate signal conditioning circuits. Passive Cable VDO Section 6.4.4.3.1.6 VCONN Powered USB Device Shall be used when the Product is a PDUSB VCONN Powered USB Device. VPD VDO Section 6.4.4.3.1.9 Table 6.36 Product Types (DFP) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. DFP VDO Section 6.4.4.3.1.7 PDUSB Host Shall be used when the Product is a PDUSB Host or a PDUSB host that supports one or more Alternate Modes as an AMC. DFP VDO Section 6.4.4.3.1.6 Charger Shall be used when the Product is a Charger. DFP VDO Section 6.4.4.3.1.9 Page 172 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.8 Vendor ID Manufacturers Shall set the USB Vendor ID field to the value of the Vendor ID assigned to them by USB-IF. For USB Devices or Hubs which support USB Communications the USB Vendor ID field Shall be identical to the Vendor ID field defined in the product's USB Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.4.4.3.1.2 Cert Stat VDO The Cert Stat VDO Shall contain the XID assigned by USB-IF to the product before certification in binary format. The fields in the Cert Stat VDO Shall be as defined in Table 6.37, "Cert Stat VDO". 6.4.4.3.1.3 Product VDO The Product VDO contains identity information relating to the product. The fields in the Product VDO Shall be as defined in Table 6.38, "Product VDO". Manufacturers Should set the USB Product ID field to a unique value identifying the product and Should set the bcdDevice field to a version number relevant to the release version of the product. 6.4.4.3.1.4 UFP VDO The UFP VDO defined in this section Shall be returned by Ports capable of operating as a UFP including traditional USB peripherals, USB Hub's upstream Port and DRD capable host Ports. The UFP VDO defined in this section Shall be sent when the Product Type (UFP) field in the ID Header VDO is given as a PDUSB Peripheral or PDUSB Hub. Table 6.39, "UFP VDO" defines the UFP VDO that Shall be sent based on the Product Type. A [USB4] UFP Shall support the Structured VDM Discover Identity Command. Table 6.37 Cert Stat VDO Bit(s) Description Reference B31...0 32-bit unsigned integer, XID Assigned by USB-IF Table 6.38 Product VDO Bit(s) Description Reference B31...16 16-bit unsigned integer, USB Product ID [USB 2.0]/[USB 3.2] B15...0 16-bit unsigned integer, bcdDevice [USB 2.0]/[USB 3.2] Table 6.39 UFP VDO Bit(s) Description Reference B31…29 UFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.3 = 011b Values 100b…111b are Reserved, Shall Not be used. B28 Reserved Shall be set to zero. B27…24 Device Capability Bit Description 0 [USB 2.0] Device Capable 1 [USB 2.0] Device Capable (Billboard only) 2 [USB 3.2] Device Capable 3 [USB4] Device Capable B23…22 Connector Type (Legacy) Deprecated, Shall be set to 00b. B21…11 Reserved Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 173 6.4.4.3.1.4.1 VDO Version Field The UFP VDO Version field contains a VDO Version for this VDM Version number. This field indicates the expected content for the UFP VDOs. 6.4.4.3.1.4.2 Device Capability Field The Device Capability bit-field describes the UFP's Capabilities when operating as either a PDUSB Device or PDUSB Hub. B10…8 VCONN Power When the VCONN Required field is set to “Yes” the VCONN Power Field indicates the VCONN power needed by the AMA for full functionality:  000b = 1W  001b = 1.5W  010b = 2W  011b = 3W  100b = 4W  101b = 5W  110b = 6W 111b = Reserved, Shall Not be used. When the VCONN Required field is set to “No” the VCONN Power field is Reserved and Shall be set to zero. B7 VCONN Required Indicates whether the AMA requires VCONN in order to function.  0 = No  1 = Yes When the Alternate Modes field indicates no modes are supported, the VCONN Required field is Reserved and Shall be set to zero. B6 VBUS Required Indicates whether the AMA requires VBUS in order to function.  0 = Yes  1 = No When the Alternate Modes field indicates no modes are supported, the VBUS Required field is Reserved and Shall be set to zero. B5…3 Alternate Modes Bit Description 0 Supports [TBT3] Alternate Mode 1 Supports Alternate Modes that reconfigure the signals on the [USB Type-C 2.4] connector – except for [TBT3]. 2 Supports Alternate Modes that do not reconfigure the signals on the [USB Type-C 2.4] connector. B2…0 USB Highest Speed  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b =[USB4] Gen4  101b…111b = Reserved and Shall be set to zero. Table 6.39 UFP VDO (Continued) Bit(s) Description Reference Page 174 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The bits in the bit-field Shall be non-zero when the corresponding USB Device speed is supported and Shall be set to zero when the corresponding USB Device speed is not supported. [USB 2.0] "Device capable" and "Device capable Billboard only" (bits 0 and 1) Shall Not be simultaneously set. 6.4.4.3.1.4.3 Connector Type Field Th Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.4.4 VCONN Power Field When the VCONN Required field indicates that VCONN is required the VCONN Power field Shall indicate how much power an AMA needs in order to fully operate. When the VCONN Required field is set to "No" the VCONN Power field is Reserved and Shall be set to zero. 6.4.4.3.1.4.5 VCONN Required Field The VCONN Required field Shall indicate whether VCONN is needed for the AMA to operate. The VCONN Required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.6 VBUS Required Field The VBUS Required field Shall indicate whether VBUS is needed for the AMA to operate. The VBUS required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.7 Alternate Modes Field The Alternate Modes field Shall be used to identify all the types of Alternate Modes, if any, a device supports. 6.4.4.3.1.4.8 USB Highest Speed Field The USB Highest Speed field Shall indicate the Port's highest speed capability. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 175 6.4.4.3.1.5 DFP VDO The DFP VDO Shall be returned by Ports capable of operating as a DFP; including those implemented by Hosts, Hubs and Power Bricks. The DFP VDO Shall be returned when the Product Type (DFP) field in the ID Header VDO is given as Power Brick, PDUSB Host or PDUSB Hub. Table 6.40, "DFP VDO" defines the DFP VDO that Shall be sent. 6.4.4.3.1.5.1 VDO Version Field The DFP VDO Version field Shall contain a VDO Version for this VDM Version number. This field indicates the expected content for the DFP VDO. 6.4.4.3.1.5.2 Host Capability Field The Host Capability bit-field Shall describe whether the DFP can operate as a PDUSB Host and the DFP's Capabilities when operating as a PDUSB Host. Power Bricks and PDUSB Hubs Shall set the Host Capability bits to zero. 6.4.4.3.1.5.3 Connector Type Field The Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.5.4 Port Number Field The Port Number field Shall be a Static unique number that unambiguously identifies each [USB Type-C 2.4] DFP, including DRPs, on the device. Note: This number is independent of the USB Port number. Table 6.40 DFP VDO Bit(s) Field Description B31…29 DFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.2 = 010b Values 011b…111b are Reserved and Shall Not be used B28…27 Reserved Shall be set to zero. B26…24 Host Capability Bit Description 0 [USB 2.0] Host Capable 1 [USB 3.2] Host Capable 2 [USB4] Host Capable B23…22 Connector Type (Legacy) Shall be set to 00b. B21…5 Reserved Shall be set to zero. B4…0 Port Number Unique Port number to identify a specific Port on a multi-Port device. Page 176 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.6 Passive Cable VDO The Passive Cable VDO defined in this section Shall be sent when the Product Type is given as Passive Cable. Table 6.41, "Passive Cable VDO" defines the Cable VDO which Shall be sent. A Passive Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. A Passive Cable Shall Not incorporate data bus signal conditioning circuits and hence has no concept of Super Speed Directionality. A Passive Cable Shall include a VBUS wire and Shall only respond to SOP’ Communication. Passive Cables Shall support the Structured VDM Discover Identity Command and Shall return the Passive Cable VDO in a Discover Identity Command ACK as shown in Table 6.41, "Passive Cable VDO". Table 6.41 Passive Cable VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive (Passive Cable)  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Passive Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency (Passive Cable)  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b – > 70ns (>~7m) Note: 1001b ….1111b Reserved and Shall Not be used B12…11 Cable Termination Type (Passive Cable)  00b = VCONN not required. Cable Plugs that only support Discover Identity Commands Shall set these bits to 00b.  01b = VCONN required  10b…11b = Reserved and Shall Not be used B10…9 Maximum VBUS Voltage (Passive Cable) Maximum Cable VBUS Voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 177 6.4.4.3.1.6.1 HW Version Field The HW Version (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.6.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.6.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.6.4 USB Type-C plug to USB Type-C/Captive Field The USB Type-C plug to USB Type-C/Captive (Passive Cable) field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.6.5 EPR Mode Capable The EPR Capable (Passive Cable) bit is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.6.6 Cable Latency Field The Cable Latency (Passive Cable) field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. 6.4.4.3.1.6.7 Cable Termination Type Field The Cable Termination Type (Passive Cable) field (B12…11) Shall contain a value indicating whether the Passive Cable needs VCONN only initially in order to support the Discover Identity Command, after which it can be removed, or the Passive Cable needs VCONN to be continuously applied in order to power some feature of the Cable Plug. 6.4.4.3.1.6.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Passive Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated using a Fixed Supply over the cable as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage (Passive Cable) field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Passive B6…5 VBUS Current Handling Capability (Passive Cable)  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4…3 Reserved Shall be set to zero. B2…0 USB Highest Speed (Passive Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.41 Passive Cable VDO (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 178 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Passive Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.6.9 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Passive Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. 6.4.4.3.1.6.10 USB Highest Speed Field The USB Highest Speed (Passive Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 179 6.4.4.3.1.7 Active Cable VDOs An Active Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. An Active Cable Shall incorporate data bus signal conditioning circuits and May have a concept of Super Speed Directionality on its Super Speed wires. An Active Cable May include a VBUS wire. An Active Cable:  Shall respond to SOP’ Communication.  May respond to SOP’’ Communication.  Shall support the Structured VDM Discover Identity Command.  In the Discover Identity Command ACK:  Shall set the Product Type in the ID Header VDO to Active Cable.  Shall return the Active Cable VDOs defined in Table 6.42, "Active Cable VDO1" and Table 6.43, "Active Cable VDO2".. Table 6.42 Active Cable VDO1 Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Active Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b –1000ns (~100m)  1001b –2000ns (~200m)  1010b – 3000ns (~300m)  1001b ….1111b Reserved and Shall Not be used Note: Includes latency of electronics in Active Cable. B12…11 Cable Termination Type (Active Cable)  00b…01b = Reserved and Shall Not be used  10b = One end Active, one end passive, VCONN required  11b = Both ends Active, VCONN required 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 180 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 B10…9 Maximum VBUS Voltage (Active Cable) Maximum Cable VBUS voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. B8 SBU Supported  0 = SBU connections supported  1 = SBU connections are not supported B7 SBU Type When SBU Supported = 1 this bit Shall be Ignored When SBU Supported = 0:  0 = SBU is passive  1 = SBU is active B6…5 VBUS Current Handling Capability (Active Cable) When VBUS Through Cable is “No”, this field Shall be Ignored. When VBUS Through Cable is “Yes”:  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4 VBUS Through Cable  0 = No  1 = Yes B3 SOP’’ Controller Present  0 = No SOP’’ controller present  1 = SOP’’ controller present B2…0 USB Highest Speed (Active Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.43 Active Cable VDO2 Bit(s) Field Description B31…24 Maximum Operating Temperature The maximum internal operating temperature in °C. It might or might not reflect the plug’s skin temperature. B23…16 Shutdown Temperature The temperature, in °C, at which the cable will go into thermal shutdown so as not to exceed the allowable plug skin temperature. B15 Reserved Shall be set to zero. B14…12 U3/CLd Power  000b: >10mW  001b: 5-10mW  010b: 1-5mW  011b: 0.5-1mW  100b: 0.2-0.5mW  101b: 50-200µW  110b: <50µW  111b: Reserved and Shall Not be used Table 6.42 Active Cable VDO1 (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 181 6.4.4.3.1.7.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.7.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.7.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for the Active Cable VDOs. 6.4.4.3.1.7.4 Connector Type Field The USB Type-C plug to USB Type-C/Captive field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.7.5 EPR Mode Capable The EPR Capable (Active Cable) is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.7.6 Cable Latency Field The Cable Latency field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. B11 U3 to U0 transition mode  0b: U3 to U0 direct  1b: U3 to U0 through U3S B10 Physical connection  0b = Copper  1b = Optical B9 Active element  0b = Active Re-driver  1b = Active Re-timer B8 USB4 Supported  0b = [USB4] supported  1b = [USB4]not supported B7…6 USB 2.0 Hub Hops Consumed Number of [USB 2.0] ‘hub hops’ cable consumes. Shall be set to zero if USB 2.0 not supported. B5 USB 2.0 Supported  0b = [USB 2.0] supported  1b = [USB 2.0] not supported B4 USB 3.2 Supported  0b = [USB 3.2] SuperSpeed supported  1b = [USB 3.2] SuperSpeed not supported B3 USB Lanes Supported  0b = One lane  1b = Two lanes B2 Optically Isolated Active Cable  0b = No  1b = Yes B1 USB4 Asymmetric Mode Supported  0b = No  1b = Yes Shall be set to zero if asymmetry is not supported. B0 USB Gen  0b = Gen 1  1b = Gen 2 or higher Note: See VDO1 USB Highest Speed for details of Gen supported. Table 6.43 Active Cable VDO2 (Continued) Bit(s) Field Description Page 182 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.7.7 Cable Termination Type Field The Cable Termination Type (Active Cable) field (B12…11) Shall contain a value corresponding to whether the Active Cable has one or two Cable Plugs requiring power from VCONN. 6.4.4.3.1.7.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Active Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. When this field is set to 20V, the cable will safely carry a Programmable Power Supply APDO of 20V where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Active Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Active Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.7.9 SBU Supported Field The SBU Supported field (B8) Shall indicate whether the cable supports the SBUs in the cable. 6.4.4.3.1.7.10 SBU Type Field The SBU Type field (B7) Shall indicate whether the SBUs are passive or active (e.g., digital). 6.4.4.3.1.7.11 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Active Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. The VBUS Current Handling Capability (Active Cable) field Shall only be Valid when the VBUS Current Handling Capability (Active Cable) field indicates an end-to-end VBUS wire. 6.4.4.3.1.7.12 VBUS Through Cable Field The VBUS Through Cable field (B4) Shall indicate whether the cable contains an end-to-end VBUS wire. 6.4.4.3.1.7.13 SOP'' Controller Present Field The SOP’’ Controller Present field (B3) Shall indicate whether one of the Cable Plugs is capable of SOP’’ Communication in addition to the Normative SOP’ Communication. 6.4.4.3.1.7.14 USB Highest Speed Field The USB Highest Speed (Active Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. 6.4.4.3.1.7.15 Maximum Operating Temperature Field Maximum Operating Temperature field (B31…24) Shall report the maximum allowable operating temperature inside the plug in °C. 6.4.4.3.1.7.16 Shutdown Temperature Field Shutdown Temperature field (B23…16) Shall indicate the temperature inside the plug, in °C, at which the plug will shut down its active signaling components. When this temperature is reached, it will be reported in the Active Cable Status Message through the Thermal Shutdown bit. 6.4.4.3.1.7.17 U3/CLd Power Field The U3/CLd Power field (B14…12) Shall indicate the power the cable consumes while in [USB 3.2] U3 or [USB4] CLd. 6.4.4.3.1.7.18 U3 to U0 Transition Mode Field The U3 to U0 transition mode field (B11) Shall indicate which U3 to U0 mode the cable supports. This does not include the power in U3S if supported. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 183 6.4.4.3.1.7.19 Physical Connection Field The Physical connection field (B10) Shall indicate the cable's construction, whether the connection between the active elements is copper or optical. 6.4.4.3.1.7.20 Active element Field The Active element field (B9) Shall indicate the cable's active element, whether the active element is a re-timer or a re-driver. 6.4.4.3.1.7.21 USB4 Supported Field The USB4 Supported field (B8) Shall indicate whether or not the cable supports [USB4] operation. 6.4.4.3.1.7.22 USB 2.0 Hub Hops Consumed field The USB 2.0 Hub Hops Consumed field (B7…6) Shall indicate the number of USB 2.0 'hub hops' that are lost due to the transmission time of the cable. 6.4.4.3.1.7.23 USB 2.0 Supported Field The USB 2.0 Supported field (B5) Shall indicate whether or not the cable supports [USB 2.0] only signaling. 6.4.4.3.1.7.24 USB 3.2 Supported Field The USB 3.2 Supported field (B4) Shall, indicate whether or not the cable supports [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.25 USB Lanes Supported Field The USB Lanes Supported field (B3) Shall indicate whether the cable supports one or two lanes of [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.26 Optically Isolated Active Cable Field The Optically Isolated Active Cable field (B2) Shall indicate whether this cable is an optically isolated Active Cable or not (as defined in [USB Type-C 2.4]). Optically Isolated Active Cables Shall have a re-timer or linear re-driver (LRD) as the active element and do not support [USB 2.0] or carry VBUS. 6.4.4.3.1.7.27 USB4 Asymmetric Mode Supported Field The USB4 Asymmetric Mode Supported field (B1) Shall indicate that the Active Cable supports asymmetric mode as defined in [USB4] and [USB Type-C 2.4]. 6.4.4.3.1.7.28 USB Gen Field The USB Gen field (B0) Shall indicate the signaling Gen the cable supports. Gen 1 Shall only be used by [USB 3.2] cables as indicated by the USB 3.2 Supported field. Gen 2 or higher May be used by either [USB 3.2] or [USB4] cables as indicated by their respective supported fields. When Gen 2 or higher is indicated the USB Highest Speed (Active Cable) field in VDO1 Shall indicate the actual Gen supported. 6.4.4.3.1.8 Alternate Mode Adapter VDO The Alternate Mode Adapter (AMA) VDO has been Deprecated. PDUSB Devices which support one or more Alternate Modes Shall set an appropriate Product Type (UFP), and Shall set the Modal Operation Supported bit to '1'. Page 184 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.9 VCONN Powered USB Device VDO The VCONN Powered USB Device (VPD) VDO defined in this section Shall be sent when the Product Type is given as VCONN Powered USB Device. Table 6.44, "VPD VDO" defines the VPD VDO which Shall be sent. 6.4.4.3.1.9.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.9.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.9.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.9.4 Maximum VBUS Voltage Field The Maximum VBUS Voltage field (B16…15) Shall contain the maximum voltage that a Sink Shall Negotiate through the VPD Charge Through Port as part of an Explicit Contract. Note: The maximum voltage that will be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Table 6.44 VPD VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b  Values 001b…111b are Reserved and Shall Not be used. B20...17 Reserved Shall be set to zero. B16…15 Maximum VBUS Voltage Maximum VPD VBUS Voltage:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V1 (Deprecated) B14 Charge Through Current Support Charge Through Current Support bit=1b:  0b - 3A capable.  1b - 5A capable Charge Through Current Support bit = 0b:  Reserved and Shall be set to zero. B13 Reserved Shall be set to zero. B12…7 VBUS Impedance Charge Through Current Support bit = 1b: VBUS impedance through the VPD in 2 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Reserved and Shall be set to zero. B6…1 Ground Impedance Charge Through Current Support bit = 1b: Ground impedance through the VPD in 1 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Shall be set to zero. B0 Charge Through Support  1b – the VPD supports Charge Through  0b – the VPD does not support Charge Through 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 185 Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Maximum VBUS Voltage field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.9.5 VBUS Impedance Field The VBUS Impedance field (B12…7) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the VBUS IR Drop limit of 0.5V between the Source and itself. If the Sink can tolerate a larger IR Drop on VBUS it May do so. 6.4.4.3.1.9.6 Ground Impedance Field The Ground Impedance field (B6…1) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the Ground IR Drop limit of 0.25V between the Source and itself. 6.4.4.3.1.9.7 Charge Through Field The Firmware Version field (B0) Shall be set to 1b when the VPD supports Charge Through and 0b otherwise. Page 186 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.2 Discover SVIDs The Discover SVIDs Command is used by an Initiator to determine the SVIDs for which a Responder has Modes. The Discover SVIDs Command is used in conjunction with the Discover Modes Command in the Discovery Process to determine which Modes a device supports. The list of SVIDs is always terminated with one or two 0x0000 SVIDs. The SVID in the Discover SVIDs Command Shall be set to the PD SID (see "Table 6.31, "SVID Values") by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover SVIDs Command request Shall be set to 1 since the Discover SVIDs Command request Shall Not contain any VDOs. The Discover SVIDs Command ACK sent back by the Responder Shall contain one or more SVIDs. The SVIDs are returned 2 per VDO (see Table 6.45, "Discover SVIDs Responder VDO"). If there are an odd number of supported SVIDs, the Discover SVIDs Command is returned ending with a SVID value of 0x0000 in the last part of the last VDO. If there are an even number of supported SVIDs, the Discover SVIDs Command is returned ending with an additional VDO containing two SVIDs with values of 0x0000. A Responder Shall only return SVIDs for which a Discover Modes Command request for that SVID will return at least one Alternate Mode. A Responder that does not support any SVIDs Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover SVIDs Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the Responder supports 12 or more SVIDs then the Discover SVIDs Command Shall be executed multiple times until a Discover SVIDs VDO is returned ending either with a SVID value of 0x0000 in the last part of the last VDO or with a VDO containing two SVIDs with values of 0x0000. Each Discover SVID ACK Message, other than the one containing the terminating 0x0000 SVID, Shall convey 12 SVIDs. The Responder Shall restart the list of SVIDs each time a Discover Identity Command request is received from the Initiator. Note: Since a Cable Plug does not retry Messages if the GoodCRC Message from the Initiator becomes corrupted the Cable Plug will consider the Discover SVIDs Command ACK unsent and will send the same list of SVIDs again. Figure 6.18, "Example Discover SVIDs response with 3 SVIDs" shows an example response to the Discover SVIDs Command request with two VDOs containing three SVIDs. Figure 6.19, "Example Discover SVIDs response with 4 SVIDs" shows an example response with two VDOs containing four SVIDs followed by an empty VDO to terminate the response. Figure 6.20, "Example Discover SVIDs response with 12 SVIDs followed by an empty response" shows an example response with six VDOs containing twelve SVIDs followed by an additional request that returns an empty VDO indicating there are no more SVIDs to return. Figure 6.18 Example Discover SVIDs response with 3 SVIDs Table 6.45 Discover SVIDs Responder VDO Bit(s) Field Description B31…16 SVID n 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an even number of SVIDs. B15…0 SVID n+1 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an odd or even number of SVIDs. Header No. of Data Objects = 3 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) 0x0000 (B15..0) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 187 Figure 6.19 Example Discover SVIDs response with 4 SVIDs Figure 6.20 Example Discover SVIDs response with 12 SVIDs followed by an empty response Header No. of Data Objects = 4 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 0x0000 (B31..16) 0x0000 (B15..0) Header No. of Data Objects = 7 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 SVID 4 (B31..16) SVID 5 (B15..0) VDO 4 SVID 6 (B31..16) SVID 7 (B15..0) VDO 5 SVID 8 (B31..16) SVID 9 (B15..0) Header No. of Data Objects = 2 VDM Header VDO 1 0x0000 (B31..16) 0x0000 (B15..0) VDO 6 SVID 10 (B31..16) SVID 11 (B15..0) Page 188 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.3 Discover Modes The Discover Modes Command is used by an Initiator to determine the Modes a Responder supports for a given SVID. The SVID in the Discover Modes Command Shall be set to the SVID for which Modes are being requested by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover Modes Command request Shall be set to 1 since the Discover Modes Command request Shall Not contain any VDOs. The Discover Modes Command ACK sent back by the Responder Shall contain one or more Modes. The Discover Modes Command ACK Shall contain a Message Header with the Number of Data Objects field set to a value of 2 to 7 (the actual value is the number of Alternate Mode objects plus one). If the ID is a VID, the structure and content of the VDO is left to the Vendor. If the ID is a SID, the structure and content of the VDO is defined by the relevant standard’s body. A Responder that does not support any Modes Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover Modes Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes" shows an example of a Discover Modes Command response from a Responder which supports three Modes for a given SVID. Figure 6.21 Example Discover Modes response for a given SVID with 3 Modes 6.4.4.3.4 Enter Mode Command The Enter Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to enter a specified Alternate Mode of operation. Only a DFP Shall initiate the Enter Mode Process which it starts after it has successfully completed the Discovery Process. The value in the Object Position field in the VDM Header Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes"). The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. The Number of Data Objects field in the Message Header in the Command request Shall be set to either 1 or 2 since the Enter Mode Command request Shall Not contain more than 1 VDO. When a VDO is included in an Enter Mode Command request the contents of the 32-bit VDO is defined by the Alternate Mode. The Number of Data Objects field in the Command response Shall be set to 1 since an Enter Mode Command response (ACK, NAK) Shall Not contain any VDOs. Before entering a Alternate Mode, by sending the Enter Mode Command request that requires the reconfiguring of any pins on entry to that Alternate Mode, the Initiator Shall ensure that those pins being reconfigured are placed into the USB Safe State. Before entering an Alternate Mode that requires the reconfiguring of any pins, the Responder Shall ensure that those pins being reconfigured are placed into either USB operation or the USB Safe State. A device May support multiple Modes with one or more active at any point in time. Any interactions between them are the responsibility of the Standard or Vendor. Where there are multiple Active Modes at the same time Modal Operation Shall start on entry to the first Alternate Mode. Header No. of Data Objects = 4 VDM Header Mode 1 Mode 2 Mode 3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 189 On receiving an Enter Mode Command requests the Responder Shall respond with either an ACK or a NAK response. The Responder is not allowed to return a BUSY response. The value in the Object Position field of the Enter Mode Command response Shall contain the same value as the received Enter Mode Command request. If the Responder responds to the Enter Mode Command request with an ACK, the Responder Shall enter the Alternate Mode before sending the ACK. The Initiator Shall enter the Alternate Mode on reception of the ACK. Successful transmission of the Message confirms to the Responder that the Initiator will enter an Active Mode. See Figure 8.111, "DFP to UFP Enter Mode" for more details. If the Responder responds to the Enter Mode Command request with a NAK, the Alternate Mode is not entered. If not presently in Modal Operation the Initiator Shall return to USB operation. If not presently in Modal Operation the Responder Shall remain in either USB operation or the USB Safe State. If the Initiator fails to receive a response within tVDMWaitModeEntry it Shall Not enter the Alternate Mode but return to USB operation. Figure 6.22, "Successful Enter Mode sequence" shows the sequence of events during the transition between USB operation and entering an Alternate Mode. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.23, "Unsuccessful Enter Mode sequence due to NAK" illustrates that when the Responder returns a NAK the transition to an Alternate Mode do not take place and the Responder and Initiator remain in their default USB roles. Figure 6.22 Successful Enter Mode sequence DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC ACK USB Safe State USB USB or USB Safe State New Mode New Mode Page 190 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.23 Unsuccessful Enter Mode sequence due to NAK Once the Alternate Mode is entered, the device Shall remain in that Active Mode until the Exit Mode Command is successful (see Section 6.4.4.3.5, "Exit Mode Command"). The following events Shall also cause the Port Partners and Cable Plug(s) to exit all Active Modes:  A PD Hard Reset.  Error Recovery.  The Port Partners or Cable Plug(s) are Detached.  A Cable Reset (only exits the Cable Plug's Active Modes).  A Data Reset (removing power briefly resets all the Active Modes in the Cable Plug). The Initiator Shall return to USB Operation within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. The Responder Shall return to either USB operation or USB Safe State within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. A DR_Swap Message Shall Not be sent during Modal Operation between the Port Partners (see Section 6.3.9, "DR_Swap Message"). 6.4.4.3.5 Exit Mode Command The Exit Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to exit its Active Mode and return to normal USB operation. Only the DFP Shall initiate the Exit Mode Process. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC NAK USB Safe State USB USB or USB Safe State USB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 191 Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 111b in the Object Position field Shall indicate that all Active Modes Shall be exited. The Number of Data Objects field in both the Command request and Command response (ACK, NAK) Shall be set to 1 since an Exit Mode Command Shall Not contain any VDOs. The Responder Shall exit its Active Mode before sending the response Message. The Initiator Shall exit its Active Mode when it receives the ACK. The Responder Shall Not return a BUSY acknowledgment and Shall only return a NAK acknowledgment to a request not containing an Active Mode (i.e., Invalid object position). An Initiator which fails to receive an ACK within tVDMWaitModeExit or receives a NAK or BUSY response Shall exit its Active Mode. See Figure 8.112, "DFP to UFP Exit Mode" for more details. Figure 6.24, "Exit Mode sequence" shows the sequence of events during the transition between exiting an Active Mode and USB operation. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.24 Exit Mode sequence 6.4.4.3.6 Attention The Attention Command May be used by the Initiator to notify the Responder that it requires service. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 000b or 111b in the Object Position field Shall Not be used by the Attention Command. DFP (Initiator) UFP (Responder) Exit Mode GoodCRC GoodCRC ACK USB Safe State USB or USB Safe State Mode Mode USB Page 192 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Number of Data Objects field in the Message Header Shall be set to 1 or 2 since the Attention Command Shall Not contain more than 1 VDO. When a VDO is included in an Attention Command the contents of the 32-bit VDO is defined by the Alternate Mode. Figure 6.24, "Exit Mode sequence" shows the sequence of events when an Attention Command is received. Figure 6.25 Attention Command request/response sequence 6.4.4.4 Command Processes The Message flow of Commands during a Process is a query followed by a response. Every Command request sent has to be responded to with a GoodCRC Message. The GoodCRC Message only indicates the Command request was received correctly; it does not mean that the Responder understood or even supports a particular SVID. Figure 6.26, "Command request/response sequence" shows the request/response sequence including the GoodCRC Messages. Initiator Responder GoodCRC Command (Attention) Command Complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 193 Figure 6.26 Command request/response sequence In order for the Initiator to know that the Command request was actually consumed, it needs an acknowledgment from the Responder. There are three responses that indicate the Responder received and processed the Command request:  ACK  NAK  BUSY The Responder Shall complete:  Enter Mode requests within tVDMEnterMode.  Exit Mode requests within tVDMExitMode.  Other requests within tVDMReceiverResponse. An Initiator not receiving a response within the following times Shall timeout and return to either the PE_SRC_Ready or PE_SNK_Ready state (as appropriate):  Enter Mode requests within tVDMWaitModeEntry.  Exit Mode requests within tVDMWaitModeExit.  Other requests within tVDMSenderResponse. The Responder Shall respond with:  ACK if it recognizes the SVID and can process it at this time.  NAK:  if it recognizes the SVID but cannot process the Command request Initiator Responder Command (request) GoodCRC GoodCRC Command (response) Command Complete Page 194 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  or if it does not recognize the SVID  or if it does not support the Command  or if a VDO contains a field which is Invalid.  BUSY if it recognizes the SVID and the Command but cannot process the Command request at this time. The ACK, NAK or BUSY response Shall contain the same SVID as the Command request. 6.4.4.4.1 Discovery Process The Initiator (usually the DFP) always begins the Discovery Process. The Discovery Process has two phases. In the first phase, the Discover SVIDs Command request is sent by the Initiator to get the list of SVIDs the Responder supports. In the second phase, the Initiator sends a Discover Modes Command request for each SVID supported by both the Initiator and Responder. 6.4.4.4.2 Enter Vendor Mode / Exit Vendor Mode Processes The result of the Discovery Process is that both the Initiator and Responder identify the Modes they mutually support. The Initiator (DFP), upon finding a suitable Alternate Mode, uses the Enter Mode Command to enable the Alternate Mode. The Responder (UFP or Cable Plug) and Initiator continue using the Active Mode until the Active Mode is exited. In a managed termination, using the Exit Mode Command, the Active Mode Shall be exited in a controlled manner as described in Section 6.4.4.3.5, "Exit Mode Command". In an unmanaged termination, triggered by:  A Power Delivery Hard Reset (i.e. Hard Reset Signaling sent by either Port Partner) or  By cable Detach (device unplugged) or  By Error Recovery the Active Mode Shall still be exited but there Shall Not be a transition through the USB Safe State. In both the managed and unmanaged terminations, the Initiator and Responder return to USB operation as defined in [USB Type-C 2.4] following an exit from an Alternate Mode. The overall Message flow is illustrated in Figure 6.27, "Enter/Exit Mode Process". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 195 Figure 6.27 Enter/Exit Mode Process 6.4.4.5 VDM Message Timing and Normal PD Messages The timing and interspersing of VDMs between regular PD Messages Shall be done without perturbing the PD AMSs. This requirement Shall apply to both Unstructured VDMs and Structured VDMs. Initiator (DFP) Responder (UFP or Cable Plug) Discover SVIDs List of SVIDs For every DFP supported SVID Modes Supported? N Stay in USB mode Y Enter Mode ACK (Responder switched to Mode) Initiator and Responder operate using Mode Return to USB mode Establish PD Contract Exit Mode or PD Hard Reset or cable unplugged or power removed? Y N USB USB or USB Safe State USB Safe State USB Alternate Mode USB or USB Safe State Alternate Mode USB Discover Modes (SVID) Modes for SVID Page 196 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The use of Structured VDMs by an Initiator Shall Not interfere with the normal PD Message timing requirements nor Shall either the Initiator or Responder interrupt a PD AMS (e.g., Negotiation, Power Role Swap, Data Role Swap etc.). The use of Unstructured VDMs Shall Not interfere with normal PD Message timing. 6.4.5 Battery_Status Message The Battery_Status Message Shall be sent in response to a Get_Battery_Status Message. The Battery_Status Message contains one Battery Status Data Object (BSDO) for one of the Batteries it supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BSDO Shall correspond to the Battery requested in the Battery Status Ref field contained in the Get_Battery_Status Message. The Battery_Status Message returns a BSDO whose format Shall be as shown in Figure 6.28, "Battery_Status Message" and Table 6.46, "Battery Status Data Object (BSDO)". The Number of Data Objects field in the Battery_Status Message Shall be set to 1. Figure 6.28 Battery_Status Message 6.4.5.1 Battery Present Capacity The Battery Present Capacity field Shall return either the Battery's State of Charge (SoC) in tenths of WH or indicate that the Battery's present State of Charge (SOC) is unknown. Table 6.46 Battery Status Data Object (BSDO) Bit(s) Field Description B31…16 Battery Present Capacity Battery’s State of Charge (SoC) in 0.1 WH increments Note: 0xFFFF = Battery’s SOC unknown B15…8 Battery Info Bit Description 0 Invalid Battery Reference Invalid Battery reference 1 Battery Present Battery is present when set 3…2 Battery Charging Status When Battery Present is ‘1’ Shall contain the Battery charging status:  00b: Battery is Charging.  01b: Battery is Discharging.  10b: Battery is Idle.  11b: Reserved, Shall Not be used. When Battery Present is ‘0’:  11b…00b: Reserved, Shall Not be used. 7…4 Reserved, Shall Not be used. B7…0 Reserved Shall be set to zero Header No. of Data Objects = 1 BSDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 197 6.4.5.2 Battery Info The Battery Info field Shall be used to report additional information about the Battery's present status. The Battery Info field's bits Shall reflect the present conditions under which the Battery is operating in the systems. 6.4.5.2.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Status Message contains a reference to a Battery or Battery Slot (see Section 6.5.1.13, "Number of Batteries/Battery Slots Field") that does not exist. 6.4.5.2.2 Battery Present The Battery Present bit Shall be set whenever the Battery is present. It Shall always be set for Batteries that are not Hot Swappable Batteries. For Hot Swappable Batteries, the Battery Present bit Shall indicate whether the Battery is Attached or Detached. 6.4.5.2.3 Battery Charging Status The Battery Charging Status bits indicate whether the Battery is being charged, discharged or is idle (neither charging nor discharging). These bits Shall be set when the Battery Present bit is set. Otherwise, when the Battery Present bit is zero the Battery Charging Status bits Shall also be zero. Page 198 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6 Alert Message The Alert Message is provided to allow Port Partners to inform each other when there is a status change event. Some of the events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Alert Message Shall only be sent when the Source or Sink detects a status change. The Alert Message Shall contain exactly one Alert Data Object (ADO) and the format Shall be as shown in Figure 6.29, "Alert Message" and Table 6.47, "Alert Data Object (ADO)". Figure 6.29 Alert Message Table 6.47 Alert Data Object (ADO) Bit(s) Field Description B31…24 Type of Alert Bit Description 0 Reserved and Shall be set to zero. 1 Battery Status Change Event Battery Status Change Event (Attach/Detach/charging/discharging/ idle) 2 OCP Event OCP event when set (Source only, for Sink Reserved and Shall be set to zero). 3 OTP Event OTP event when set 4 Operating Condition Change Operating Condition Change when set 5 Source Input Change Event Source Input Change Event when set 6 OVP Event OVP event when set 7 Extended Alert Event Extended Alert Event when set B23…20 Fixed Batteries When Battery Status Change Event bit set indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. B19…16 Hot Swappable Batteries When Battery Status Change Event bit set indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 4 and B19 corresponds to Battery 7. Header No. of Data Objects = 1 ADO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 199 6.4.6.1 Type of Alert The Type of Alert field Shall be used to report Source or Sink status changes. Only one Alert Message Shall be generated for each Event or Change; however multiple Type of Alert bits May be set in one Alert Message. Once the Alert Message has been sent the Type of Alert field Shall be cleared. A Get_Battery_Status Message Should be sent in response to a Battery status change in an Alert Message to get the details of the change. A Get_Status Message Should be sent in response to a non-Battery status change in an Alert Message from to get the details of the change. 6.4.6.1.1 Battery Status Change The Battery Status Change Event bit Shall be set when any Battery's power state changes between charging, discharging, neither. For Hot Swappable Batteries, it Shall also be set when a Battery is Attached or Detached. 6.4.6.1.2 Over-Current Protection Event The OCP Event bit Shall be set when a Source detects its output current exceeds its limits triggering its protection circuitry. This bit is Reserved for a Sink. 6.4.6.1.3 Over-Temperature Protection Event The OTP Event bit Shall be set when a Source or Sink shuts down due to over-temperature triggering its protection circuitry. 6.4.6.1.4 Operating Condition Change The Operating Condition Change bit Shall be set when a Source or Sink detects its Operating Condition enters or exits either the 'warning' or 'over temperature' temperature states. The Operating Condition Change bit Shall be set when the Source operating in the Programmable Power Supply mode detects it has changed its operating condition between Constant Voltage (CV) and Current Limit (CL). 6.4.6.1.5 Source Input Change Event The Source Input Change Event bit Shall be set when the Source/Sink's input changes. For example, when the AC input is removed, and the Source/Sink continues to be powered from one or more of its batteries or when AC returns and the Source/Sink transitions from Battery to AC operation or when the Source/Sink changes operation from one (or more) Battery to another (or more) Battery. B15…4 Reserved Shall be set to zero B3…0 Extended Alert Event Type When the Extended Alert Event bit in the Type of Alert field equals ‘1’, then the Extended Alert Event Type field indicates the event which has occurred:  0 = Reserved.  1 = Power state change (DFP only)  2 = Power button press (UFP only)  3 = Power button release (UFP only)  4 = Controller initiated wake e.g., Wake on LAN (UFP only)  5-15 = Reserved When the Extended Alert Event bit in the Type of Alert field equals ‘0’, then the Extended Alert Event Type field is Reserved and Shall be set to zero. Table 6.47 Alert Data Object (ADO) (Continued) Bit(s) Field Description Page 200 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6.1.6 Over-Voltage Protection Event The OVP Event bit Shall be set when the Sink detects its output voltage exceeds its limits triggering its protection circuitry. The OVP Event bit May be set when the Source detects its output voltage exceeds its limits triggering its protection circuitry. 6.4.6.1.7 Extended Alert Event The Extended Alert Event bit Shall be set when the event is defined as an Extended Alert Type. 6.4.6.2 Fixed Batteries The Fixed Batteries field indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. Once the Alert Message has been sent the Fixed Batteries field Shall be cleared. 6.4.6.3 Hot Swappable Batteries The Hot Swappable Batteries field indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 0 and B19 corresponds to Battery 3. Once the Alert Message has been sent the Hot Swappable Batteries field Shall be cleared. 6.4.6.4 Extended Alert Event Types The Extended Alert Event Type field provides extensions to the available types for the Alert Message. If the Extended Alert Event Type bit is not set, then the Extended Alert Event Type is Reserved and Shall be set to zero. 6.4.6.4.1 Power State Change The Power state change event value May be set when the DFP transitions into a new power state. The new power state Shall be communicated via the Power state change byte in the Status Message. This Message Should be sent by the host in response to any system power state change. 6.4.6.4.2 Power Button Press The Power button press event value May be set when the power button on the UFP is pressed. The press and release events are separated into two different events so that devices that respond differently to a long button press will see a long button press. On the host-side, the power button press event typically initiates the same behavior as a power button press of the host's power button. 6.4.6.4.3 Power Button Release If a Power button press event was sent, then the Power button release event value Shall be sent by the UFP following the Power button press event. If a physical power button press initiated the Power button press event, then the Power button release event Should be sent when the physical button is released. 6.4.6.4.4 Controller Initiated Wake The Controller initiated wake is used to communicate a wake event from the UFP to the DPF such as Wake on LAN from a NIC or another controller. This event doesn't need the press/release form of the Power button press, because it only needs to communicate the presence of the event, and not the timing. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 201 6.4.7 Get_Country_Info Message The Get_Country_Info Message Shall be sent by a Port to get country specific information from its Port Partner using the country's Alpha-2 Country Code defined by [ISO 3166]. The Port Partner responds with a Country_Info Message that contains the country specific information. The Get_Country_Info Message Shall be as shown in Figure 6.30, "Get_Country_Info Message" and Table 6.48, "Country Code Data Object (CCDO)". For example, if the request is for China information, then the Country Code Data Object (CCDO) would be CCDO [31:0] = 434E0000h for "CN" country code. Figure 6.30 Get_Country_Info Message Table 6.48 Country Code Data Object (CCDO) Bit(s) Description B31…24 First character of the Alpha-2 Country Code defined by [ISO 3166] B23…16 Second character of the Alpha-2 Country Code defined by [ISO 3166] B15…0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 CCDO Page 202 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8 Enter_USB Message The Enter_USB Message Shall be sent by the DFP to its UFP Port Partner and to the Cable Plug(s) of an Active Cable, when in an Explicit Contract, to enter a specified USB Mode of operation. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). When entering [USB4] operation, the Enter_USB Message Shall be sent by a [USB4] PDUSB Hub's DFP(s) or [USB4] PDUSB Host's DFP(s) within tEnterUSB:  following a PD Connection.  after a Data Reset to enter [USB4] operation is completed.  after a Data Role Swap is completed. The Enter_USB Message May be sent by a PDUSB Hub's DFP(s) or PDUSB Host's DFP(s) within tEnterUSB following a PD Connection or after a Data Reset to enter [USB 3.2] or [USB 2.0] operation. The Enter_USB Message Shall be used by a PDUSB Hub's DFP(s) to speculatively train the USB links or enter [DPTC2.1] or [TBT3] Alternate Modes prior to the presence of a host. In this case, the Host Present bit Shall be cleared. When the Host is Connected the Enter_USB Message Shall be resent with the Host Present bit set. The Enter_USB Message's Enter USB Data Object (EUDO), received from the Root Hub when the USB Host is connected, Shall be propagated down through the Hub tree. See [USB Type-C 2.4] USB4® Hub Connection Requirements. The Enter_USB Message Shall be as shown in Figure 6.31, "Enter_USB Message" and Table 6.49, "Enter_USB Data Object (EUDO)". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 203 Figure 6.31 Enter_USB Message Table 6.49 Enter_USB Data Object (EUDO) Bit(s) Field Description B31 Reserved Shall be set to zero. B30…28 USB Mode 1  000b:  001b:  010b:  111b…011b: Reserved, Shall Not be used. B27 Reserved Shall be set to zero. B26 USB4 DRD 2  0b: Not capable of operating as a [USB4] Device  1b: Capable of operating as a [USB4] Device B25 USB3 DRD 2  0b: Not capable of operating as a [USB 3.2] Device  1b: Capable of operating as a [USB 3.2] Device B24 Reserved Shall be set to zero. B23…21 Cable Speed 2,3  000b: [USB 2.0]only, no SuperSpeed support  001b: [USB 3.2] Gen1  010b: [USB 3.2]Gen2 and [USB4] Gen2  011b: [USB4] Gen3  100b: [USB4] Gen4  101b…111b: Reserved, Shall Not be used. B20…19 Cable Type 2,3  00b: Passive  01b: Active Re-timer  10b: Active Re-driver  11b: Optically Isolated B18…17 Cable Current 2  00b = VBUS is not supported  01b = Reserved  10b = 3A  11b = 5A B16 PCIe Support 2 [USB4] PCIe tunneling supported by the host B15 DP Support 2 [USB4] DP tunneling supported by the host B14 TBT Support 2 [TBT3] is supported by the host’s USB4® Connection Manager B13 Host Present 2 A Host is present at the top of the USB tree. When this bit is set PCIe Support, DP Support and TBT Support represent the Host’s Capabilities that Shall be propagated down the Hub tree. B12…0 Reserved Shall be set to zero. 1) Entry into [USB 3.2] and [USB4] include entry into [USB 2.0]. 2) Shall be Ignored when received by a Cable Plug (e.g., SOP’ or SOP’’). 3) The DFP Shall interpret the Cable Plug’s reported capability as defined in [USB Type-C 2.4] in the USB4 Discovery and Entry Section. Header No. of Data Objects = 1 EUDO Page 204 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8.1 USB Mode Field The USB Mode field Shall be used by the DFP to direct the USB Mode the Port Partner is to enter. 6.4.8.2 USB4® DRD Field The USB4 DRD field Shall be set when the Host DFP is capable of operating as a [USB4] Device. A [USB4] Host DFP that sets the USB4 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.3 USB3 DRD Field The USB3 DRD field Shall be set when the Host DFP is capable of operating as a [USB 3.2] Device. A [USB 3.2] Host DFP that sets the USB3 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.4 Cable Speed Field The Cable Speed field Shall be used to indicate the cable's maximum speed. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.5 Cable Type Field The Cable Type field Shall be used to indicate whether the cable is passive or active. Further if the cable is active, it indicates the type of active circuits in the cable and if the cable is optically isolated. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.6 Cable Current Field The Cable Current field Shall be used to indicate the cable's current carrying capability. The value is reported by the Cable Plug in the VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field. 6.4.8.7 PCIe Support Field The PCIe Support field Shall be set when the Host DFP is capable of tunneling PCIe over [USB4]. The PCIe Support field May be set speculatively when the Hub's DFP is capable of tunneling PCIe over [USB4]. 6.4.8.8 DP Support Field The DP Support field Shall be set when the Host DFP is capable of tunneling DP over [USB4]. The DP Support field May be set speculatively when the Hub's DFP is capable of tunneling DP over [USB4]. 6.4.8.9 TBT Support Field The TBT Support field Shall be set when the Host DFP is capable of tunneling ThunderboltTM over [USB4] and that the Connection Manager (CM) supports discovery and configuration of Thunderbolt 3 devices connected to the DFP of [USB4] Hubs. The TBT Support field May be set speculatively when the Hub's DFP is capable of tunneling Thunderbolt over [USB4]. 6.4.8.10 Host Present Field The Host Present field Shall be set to indicate that a Host is present upstream. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 205 6.4.9 EPR_Request Message An EPR_Request Message Shall be sent by a Sink, operating in EPR Mode, to request power, typically during the request phase of a power Negotiation. The EPR_Request Message Shall be sent in response to the most recent EPR_Source_Capabilities Message. The EPR_Request Message Shall return a Sink Request Data Object (RDO) that Shall identify the Power Data Object being requested followed by a copy of the Power Data Object being requested. Note: The requested Power Data Object May be either an EPR (A)PDO or SPR (A)PDO. The EPR_Request Message Shall be as shown in Figure 6.32, "EPR_Request Message". Figure 6.32 EPR_Request Message The Source Shall verify the PDO in the EPR_Request Message exactly matches the PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO. The Source Shall respond to an EPR_Request Message in the same manner as it responds to a Request Message with an Accept Message, or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Explicit Contract Negotiation process for EPR is the same as the process for SPR Mode except that the Source_Capabilities Message is replaced by the EPR_Source_Capabilities and the Request Message is replaced by the EPR_Request Message. An EPR Source operating in SPR Mode that receives a EPR_Request Message Shall initiate a Hard Reset. The RDO takes a different form depending on the kind of power requested. The PDO and APDO formats are detailed in Section 6.4.2, "Request Message". Header No. of Data Objects = 2 RDO Copy of PDO Page 206 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.10 EPR_Mode Message The EPR_Mode Message is used to enter, acknowledge, and exit the EPR Mode. The Action field is used to describe the action that is to be taken by the recipient of the EPR_Mode Message. The Data field provides additional information for the Message recipient in the EPR Mode Data Object (ERMDO). The EPR_Mode Message Shall be as shown in Figure 6.33, "EPR Mode DO Message" and Table 6.50, "EPR Mode Data Object (EPRMDO)". Figure 6.33 EPR Mode DO Message 6.4.10.1 Process to enter EPR Mode An EPR Source Shall enter EPR Mode upon request by an EPR Sink connected with an EPR Cable when able to offer the Source Capabilities as defined in the Power Rules (See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable"). For Port Partners to successfully enter EPR Mode, the following conditions must be met:  The Sink Shall request entry into the EPR Mode. Table 6.50 EPR Mode Data Object (EPRMDO) Bit(s) Field Description B31…24 Action Value Action Sent By 0x00 Reserved and Shall Not be used. 0x01 Enter Sink only 0x02 Enter Acknowledged Source only 0x03 Enter Succeeded Source only 0x04 Enter Failed Source only 0x05 Exit Sink or Source 0x06…0xFF Reserved and Shall Not be used. B23...16 Data Action Field Data Field Value Enter Shall be set to the EPR Sink Operational PDP Enter Acknowledged Shall be set to zero Enter Succeeded Shall be set to zero Enter Failed Shall be one of the following values:  0x00 - Unknown cause  0x01 - Cable not EPR Capable  0x02 –Source failed to become VCONN Source.  0x03 – EPR Capable bit not set in RDO.  0x04 – Source unable to enter EPR Mode1.  0x05 - EPR Capable bit not set in PDO. All other values are Reserved and Shall Not be used Exit Shall be set to zero B15...0 Reserved Shall be set to zero 1) The Sink May retry entering EPR Mode after receiving this Enter Failed response. Header No. of Data Objects = 1 EPRMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 207  The Source Shall verify the cable is EPR Capable.  A Sink Shall Not be Connected to the Source through a Charge Through VPD (CT-VPD).  The Source and Sink Shall already be in an SPR Explicit Contract.  The EPR Capable bit Shall be set in the Fixed Supply 5V PDO.  The EPR Capable bit Shall have been set in the RDO in the last Request Message received by the Source. To verify the cable is EPR Capable, the EPR Source Shall have already done the following (see Section 6.6.21.4, "tEPRSourceCableDiscovery"):  Discover the cable prior to entering its First Explicit Contract  Alternatively, within tEPRSourceCableDiscovery of entry into the First Explicit Contract  If it is the VCONN Source, discover the cable.  If not the VCONN Source, do a VCONN Swap then discover the cable. and can verify the cable is EPR Capable by completing steps 5 and 6 in the entry process in Figure 6.34, "Illustration of process to enter EPR Mode". The EPR Mode entry process is a Non-interruptible multi-Message AMS. An illustration of this AMS is shown in Figure 6.34, "Illustration of process to enter EPR Mode". Note: Figure 6.34, "Illustration of process to enter EPR Mode" is not Normative but is Informative only. Page 208 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.34 Illustration of process to enter EPR Mode The entry process Shall follow these steps in order: 1) The Sink Shall send the EPR_Mode Message with the Action field set to 1 (Enter) and the Data field set to its Operational PDP. If the EPR Source receives an EPR_Mode Message with the Action field not set to Enter it Shall initiate a Soft Reset. 2) The Source Shall do the following: EPR_Mode Enter #1 Start SPR Mode EPR Mode Sink Source Cable EPR Entry process SPR contract in place #2.a Sink EPR Capable? Abort EPR Entry Send Entry Failed – Sink not EPR Capable #2.b Source EPR Capable? Abort EPR Entry Send Entry Failed – Source not EPR Capable #2.c Source EPR Capable Now? Abort EPR Entry Send Entry Failed – Source unable to enter EPR #2.d Send EPR Ack #3 Received EPR Ack? #4 Known Cable? #7 Send Enter Succeeded N N N N N #5 Is VCONN Source? #8 Received Enter successful? N Error Send Soft Reset #6.a-d EPR Cable? Abort EPR Entry Send Entry Failed – Source not VCONN Source N Y Y Y Y EPR_MODE Enter Succeeded Y Y Y #5 Is VCONN Source? N #5 VCONN Swap N Abort EPR Entry Send Entry Failed – Not EPR Cable Y Y #4 EPR Capable? Y N Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 209 a) Verify the EPR Capable bit was set in the most recent RDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 3 ("EPR Mode Capable bit not set in the RDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. b) Verify the EPR Capable bit was set in the most recent 5V Fixed Supply PDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 5 ("EPR Mode Capable bit not set in the Fixed Supply 5V PDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. c) Verify the Source is still able to support EPR Mode. If not, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and Data field set to 4 ("Unable at this time"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. The Sink May at some time in the future send another request to enter EPR Mode. d) Send an EPR_Mode Message with the Action field set to 2 (Enter Acknowledged). 3) If the Sink receives any Message, other than an EPR_Mode Message with the Action Field set to 2, the Sink Shall initiate a Soft Reset. 4) When the EPR Source has used the Discover Identity Command to determine and remembers the Cable Capabilities or the EPR Source is connected with a captive cable: a) If the cable is EPR Capable it Should go directly to Step 7, but May continue to Step 5. b) If the cable is not EPR Capable it Shall do the following: c) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 1 ("Cable not EPR capable"). d) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 5) If the Source is not the VCONN Source, it Shall send a VCONN_Swap Message a) If the Source fails to become the VCONN Source, it Shall: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 2 (not VCONN Source). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 6) The Source Shall use the Discover Identity Command to read the cable's e-Marker and verify the following: a) Cable VDO - Maximum VBUS Voltage (Passive Cable)/Maximum VBUS Voltage (Active Cable) field is 11b (50V) b) Cable VDO - VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field is 10b (5A) c) Cable VDO - EPR Capable (Passive Cable)/EPR Capable (Active Cable) field is 1b (EPR Capable) d) If the cable fails to respond to the Discover Identity Command or is not EPR Capable, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field to1 ("Cable not EPR capable"). Page 210 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 7) The Source Shall send the EPR_Mode Message with the Action field set to 3 (Enter Succeeded) and Shall enter EPR Mode. 8) If the Sink receives an EPR_Mode Message with the Action field set to 3 (Enter Succeeded) it Shall enter EPR Mode, otherwise it Shall initiate a Soft Reset. If the EPR Mode entry process successfully completes within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Source Shall send an EPR_Source_Capabilities Message within tFirstSourceCap. If the EPR Mode entry process has not been aborted or does not complete within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Sink Shall initiate a Soft Reset. 6.4.10.2 Operation in EPR Mode While operating in EPR Mode, the Source Shall only send EPR_Source_Capabilities Messages to Advertise its power Capabilities and the Sink Shall only respond with EPR_Request Messages to Negotiate Explicit Contracts. The EPR_Request Message May be for either an SPR or EPR (A)PDO. If the Source sends a Source_Capabilities Message, that is not in response to a Sink Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. If the Sink sends a Request Message, the Source Shall initiate a Hard Reset. The Source Shall monitor the CC communications path to ensure that there is periodic traffic. The Sink Shall send an EPR_KeepAlive Message when it has not sent any Messages for more than tSinkEPRKeepAlive to ensure there is timely periodic traffic. If there is no traffic for more than tSourceEPRKeepAlive, the Source Shall initiate a Hard Reset. 6.4.10.3 Exiting EPR Mode 6.4.10.3.1 Commanded Exit While in EPR Mode, either the Source or Sink May exit EPR Mode by sending an EPR_Mode Message with the Action field set to 5 (Exit). The ports Shall be in an Explicit Contract with an SPR (A)PDO prior to the EPR Mode exit process by either:  The Source sending an EPR_Source_Capabilities Message with no EPR (A)PDO s (e.g., only SPR (A)PDO s) or  The Sink negotiating a new Explicit Contract with bit 31 in the RDO set to zero (e.g., only SPR (A)PDO s)). The process to exit EPR Mode is a Non-interruptible multi-Message AMS and Shall follow these steps in order: 1) The Port Partners Shall be in an Explicit Contract with an SPR (A)PDO. 2) Either the Source or Sink Shall send an EPR_Mode Message with the Action field set to 5 (Exit) to exit the EPR Mode 3) The Source Shall send a Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit). 4) If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap of the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit), Sink Shall initiate a Hard Reset. 6.4.10.3.2 Implicit Exit EPR Mode Shall be exited as the side-effect of the Power Role Swap and Fast Role Swap processes. This is because at the end of these processes VBUS will be at vSafe5V and the Ports will be in an Implicit Contract. The New Source will then send a Source_Capabilities Message (not an EPR_Source_Capabilities Message) to begin the process of Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 211 negotiating an SPR Explicit Contract. Once an SPR Explicit Contract is entered, the Source and Sink can then enter EPR Mode if needed. 6.4.10.3.3 Exits due to errors Other critical errors can occur while in EPR Mode; these errors Shall result in Hard Reset being initiated by the Port that detects the error. Some of these errors include:  An EPR_Mode Message with the Action field set to 5 (Exit) to exit EPR Mode is received by a Port in an Explicit Contract with an EPR (A)PDO.  The Sink receives an EPR_Source_Capabilities Message with an EPR (A)PDO in any of the first seven object positions.  The (A)PDO in the EPR_Request Message does not match the (A)PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO.  The Source receives a Request Message.  The Sink receives a Source_Capabilities Message not in response to a Get_Source_Cap Message. Page 212 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.11 Source_Info Message The Source_Info Message Shall be sent in response to a Get_Source_Info Message. The Source_Info Message contains one Source Information Data Object (SIDO). The Source_Info Message returns a SIDO whose format Shall be as shown in Figure 6.35, "Source_Info Message" and Table 6.51, "Source_Info Data Object (SIDO)". The Number of Data Objects field in the Source_Info Message Shall be set to 1. The Port Maximum PDP, Port Present PDP, Port Reported PDP and the Port Type are used to identify Capabilities of a Source Port. Figure 6.35 Source_Info Message 6.4.11.1 Port Type Field Port Type is a Static field that Shall be used to indicate whether the amount of power the Port can provide is fixed or can change dynamically. For Ports that are part of a Shared Capacity Group, the Port Type field Shall be set to Managed Capability Port. For Ports not part of a Shared Capacity Group, the Port Type field May be set to either Managed Capability Port or Guaranteed Capability Port. 6.4.11.2 Port Maximum PDP Field Port Maximum PDP is a Static field that Shall report the integer portion of the PDP Rating of the Port. A Guaranteed Capability Port (as indicated by the Port Type field being set to '1') Shall always be capable of supplying this amount of power. A Managed Capability Port (as indicated by the Port Type field being set to '0') Shall be able to offer this amount of power at some time. The Port Maximum PDP Shall be the same as the larger of the SPR Source PDP Rating and the EPR Source PDP Rating in the Source_Capabilities_Extended Message. 6.4.11.3 Port Present PDP Field The Port Present PDP field Shall indicate the integer part of the amount of power the Port is presently capable of supplying including limitations due to Cable Capabilities or abnormal operating conditions (e.g., elevated temperature, low input voltage, etc.). A Guaranteed Capability Port Shall always set its Port Present PDP to be the same as its Port Maximum PDP or the highest possible value when limited. Table 6.51 Source_Info Data Object (SIDO) Bit(s) Field Description B31 Port Type  0 = Managed Capability Port  1 = Guaranteed Capability Port B30…24 Reserved Shall be set to zero B23...16 Port Maximum PDP Power the Port is designed to supply B15…8 Port Present PDP Power the Port is presently capable of supplying B7…0 Port Reported PDP Power the Port is actually advertising Header No. of Data Objects = 1 SIDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 213 A Managed Capability Port that is part of a Shared Capacity Group Shall set its Port Present PDP to Shared Port Power Available as defined in [USB Type-C 2.4] or to a lower value when limited. A Managed Capability Port that is part of an Assured Capacity Group Shall set its Port Present PDP to the Port Maximum PDP or the highest value possible when limited. 6.4.11.4 Port Reported PDP Field The Port Reported PDP field Shall track the amount of power the Port is offering in its Source_Capabilities Message or EPR_Source_Capabilities Message. The Port Reported PDP field May be dynamic or Static depending on the Port's other characteristics such as Managed/Guaranteed Capability, SPR/EPR Mode, its power policy etc. Note: The Port Reported PDP field is computed as the integer part of, the largest of the products of the voltage times current of the Fixed Supply PDOs returned in the Source_Capabilities Message or EPR_Source_Capabilities Messages. Page 214 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.12 Revision Message The Revision Message Shall be sent in response to the Get_Revision Message sent by the Port Partner. This Message is used to identify the highest Revision the Port is capable of operating at. The Revision Message contains one Revision Message Data Object (RMDO). The Revision Message returns an RMDO whose format Shall be as shown in Figure 6.36, "Revision Message Data Object"and Table 6.52, "Revision Message Data Object (RMDO)". The Number of Data Objects field in the Revision Message Shall be set to 1. Figure 6.36 Revision Message Data Object E.g., for Revision 3.2, Version 1.1 the fields would be the following:  Revision.major = 0011b  Revision.minor = 0010b  Version.major = 0001b  Version.minor = 0001b Table 6.52 Revision Message Data Object (RMDO) Bit(s) Description B31…28 Revision.major B27…24 Revision.minor B23...20 Version.major B19...16 Version.minor B15...0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 RMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 215 6.5 Extended Message An Extended Message Shall contain an Extended Message Header (indicated by the Extended field in the Message Header being set) and be followed by zero or more data bytes. Additional bytes that might be added to existing Messages in future Revision of this specification Shall be Ignored. The format of the Extended Message is defined by the Message Header's Message Type field and is summarized in Table 6.53, "Extended Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.53 Extended Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0 0000 Reserved All values not explicitly defined are Reserved and Shall Not be used. 0 0001 Source_Capabilities_Extended Source or Dual-Role Power See Section 6.5.1 SOP only 0 0010 Status Source, Sink or Cable Plug See Section 6.5.2 SOP* 0 0011 Get_Battery_Cap Source or Sink See Section 6.5.3 SOP only 0 0100 Get_Battery_Status Source or Sink See Section 6.5.4 0 0101 Battery_Capabilities Source or Sink See Section 6.5.5 SOP only 0 0110 Get_Manufacturer_Info Source or Sink See Section 6.5.6 SOP* 0 0111 Manufacturer_Info Source, Sink or Cable Plug See Section 6.5.7 SOP* 0 1000 Security_Request Source or Sink See Section 6.5.8.1 SOP* 0 1001 Security_Response Source, Sink or Cable Plug See Section 6.5.8.2 SOP* 0 1010 Firmware_Update_Request Source or Sink See Section 6.5.9.1 SOP* 0 1011 Firmware_Update_Response Source, Sink or Cable Plug See Section 6.5.9.2 SOP* 0 1100 PPS_Status Source See Section 6.5.10 SOP only 0 1101 Country_Info Source or Sink See Section 6.5.12 SOP only 0 1110 Country_Codes Source or Sink See Section 6.5.11 SOP only 0 1111 Sink_Capabilities_Extended Sink or Dual-Role Power See Section 6.5.13 SOP only 1 0000 Extended_Control Source or Sink See Section 6.5.14 SOP only 1 0001 EPR_Source_Capabilities Source or Dual-Role Power See Section 6.5.15.2 SOP only 1 0010 EPR_Sink_Capabilities Sink or Dual-Role Power See Section 6.5.15.3 SOP only 1 0011... 1 1101 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 1110 Vendor_Defined_Extended Source, Sink or Cable Plug See Section 6.5.16 SOP* 1 1111 Reserved All values not explicitly defined are Reserved and Shall Not be used. Page 216 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1 Source_Capabilities_Extended Message The Source_Capabilities_Extended Message Should be sent in response to a Get_Source_Cap_Extended Message. The Source_Capabilities_Extended Message enables a Source or a DRP to inform the Sink about its Capabilities as a Source. The Source_Capabilities_Extended Message Shall return a 25-byte Source Capabilities Extended Data Block (SCEDB) whose format Shall be as shown in Figure 6.37, "Source_Capabilities_Extended Message" andTable 6.54, "Source Capabilities Extended Data Block (SCEDB)". Figure 6.37 Source_Capabilities_Extended Message Table 6.54 Source Capabilities Extended Data Block (SCEDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 XID Value provided by the USB-IF assigned to the product 8 FW Version Firmware version number 9 HW Version Hardware version number 10 Voltage Regulation Bit Description 1…0  00b: 150mA/µs Load Step (default)  01b: 500mA/µs Load Step  11b…10b: Reserved and Shall Not be used. 2  0b: 25% IoC (default)  1b: 90% IoC 3…7 Reserved and Shall Not be used 11 Holdup Time Output will stay with regulated limits for this number of milliseconds after removal of the AC from the input.  0x00 = feature not supported Note: A value of at least 3ms Should be used (see Section 7.1.12.2, "Holdup Time Field"). 12 Compliance Compliance in SPR Mode: Bit Description 0 LPS compliant when set 1 PS1 compliant when set 2 PS2 compliant when set 3…7 Reserved and Shall Not be used 13 Touch Current Bit Description 0 Low touch current EPS when set 1 Ground pin supported when set 2 Ground pin intended for protective earth when set 3...7 Reserved and Shall Not be used Extended Header Data Size = 25 SCEDB (25-byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 217 6.5.1.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Source's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 14 Peak Current1 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 16 Peak Current2 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 18 Peak Current3 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 20 Touch Temp Temperature conforms to:  0 = [IEC 60950-1] (default)  1 = [IEC 62368-1] TS1  2 = [IEC 62368-1] TS2 Note: All other values Reserved and Shall Not be used. 21 Source Inputs Bit Description 0  0b: No external supply  1b: External supply present 1 If bit 0 is set:  0b: External supply is constrained.  1b: External supply is unconstrained. If bit 0 is not set Reserved and Shall be set to zero 2  0b: No internal Battery  1b: Internal Battery present 3...7 Reserved and Shall be set to zero 22 Number of Batteries/ Battery Slots Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 23 SPR Source PDP Rating 0…6: Source PDP Rating (EPR Source’s PDP Rating when operating in SPR Mode. 7: Reserved and Shall be set to zero 24 EPR Source PDP Rating 0…7: EPR Source PDP Rating Table 6.54 Source Capabilities Extended Data Block (SCEDB) (Continued) Offset Field Description Page 218 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Source's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.1.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.1.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.1.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.1.6 Voltage Regulation Field The Voltage Regulation field contains bits covering Load Step Slew Rate and Magnitude. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.1.6.1 Load Step Slew Rate The Source Shall report its load step response capability in bits 0…1 of the Voltage Regulation bit field. 6.5.1.6.2 Load Step Magnitude The Source Shall report its load step magnitude rate as a percentage of IoC in bit 2 of the Voltage Regulation field. 6.5.1.7 Holdup Time Field The Holdup Time field Shall contain the Source's holdup time (see Section 7.1.12.2, "Holdup Time Field"). 6.5.1.8 Compliance Field The Compliance is Static and Shall contain the standards the Source is compliant with in SPR (see Section 7.1.12.3, "Compliance Field"). 6.5.1.9 Touch Current Field The Touch Current field reports whether the Source meets certain leakage current levels and if it has a ground pin. A Source Shall set the Touch Current bit (bit 0) when their leakage current is less than 65µA rms when Source's maximum capability is less than or equal to 30W, or when their leakage current is less than 100 µA rms when its power capability is between 30W and 100W. The total combined leakage current Shall be measured in accordance with [IEC 60950-1] when tested at 250VAC rms at 50 Hz. A Source with a ground pin Shall set the Ground pin bit (bit 1). A Source whose Ground pin is intended to be connected to a protective earth Shall set both bit1 and bit 2. 6.5.1.10 Peak Current Field The Peak Current1/Peak Current2/Peak Current3 fields Shall contain the combinations of Peak Current that the Source supports (see Section 7.1.12.4, "Peak Current"). Peak Current provides a means for Source report its ability to provide current in excess of the Negotiated amount for short periods. The Peak Current descriptor defines up to three combinations of% overload, duration and duty Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 219 cycle defined as Peak Current1, Peak Current2 and Peak Current3 that the Source supports. A Source May offer no Peak Current capability. A Source Shall populate unused Peak Current bit fields with zero. The Bit Fields within Peak Current1, Peak Current2 and Peak Current3 contain the following subfields:  Percentage Overload  Shall be the maximum peak current reported in 10% increments as a percentage of the Negotiated operating current (IoC) offered by the Source. Values higher than 25 (11001b) are clipped to 250%.  Overload Period  Shall be the minimum rolling average time window in 20ms increments, where a value of 20ms is recommended.  Duty Cycle  Shall be the maximum percentage of overload period reported in 5% increments. The values Should be 5%, 10% and 50% for PeakCurrent1, PeakCurrent2, and PeakCurrent3, respectively.  VBUS Droop  Shall be set to one to indicate there is an additional 5% voltage droop on VBUS when the overload conditions occur as defined by vSrcPeak. However, it is recommended that the Source Should pro- vide VBUS in the range of vSrcNew when overload conditions occur and set this bit to zero. 6.5.1.11 Touch Temp Field The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Source's enclosure. Safety limits for the Source's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Source May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.1.12 Source Inputs Field The Source Inputs field Shall identify the possible inputs that provide power to the Source:  When bit 0 is set, the Source can be sourced by an external power supply.  When bits 0 and 1 are set, the Source can be sourced by an external power supply which is assumed to be effectively "infinite" i.e., it won't run down over time.  When bit 2 is set the Source can be sourced by an internal Battery. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. Note: Bit 2 May be set independently of bits 0 and 1. 6.5.1.13 Number of Batteries/Battery Slots Field The Number of Batteries/Battery Slots field Shall report the number of Fixed Batteries and Hot Swappable Battery Slots the Source supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. A Source Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 220 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.14 SPR Source PDP Rating Field For an SPR Source the SPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an EPR Source, the SPR Source PDP Rating field Shall report the integer portion of the maximum amount of power that the Port is designed to deliver in SPR Mode. The SPR Source PDP Rating field that is reported Shall be Static. 6.5.1.15 EPR Source PDP Rating Field For an EPR Source the EPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an SPR Source this field Shall be set to zero. The EPR Source PDP Rating field that is reported Shall be Static. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 221 6.5.2 Status Message The Status Message Shall be sent in response to a Get_Status Message. The content of the Status Message depends on the target of the Get_Status Message. When sent to SOP the Status Message returns the status of the Port's Port Partner. When sent to SOP’ or SOP’’ the Status Message returns the status of one of the Active Cable's Cable Plugs. 6.5.2.1 SOP Status Message A Status Message, sent in response to Get_Status Message to SOP, enables a Port to inform its Port Partner about the present status of the Source or Sink. Typically, a Get_Status Message will be sent by the Port after receipt of an Alert Message. Some of the reported events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Status Message returns a 7-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.38, "SOP Status Message" and Table 6.55, "SOP Status Data Block (SDB)". Figure 6.38 SOP Status Message Table 6.55 SOP Status Data Block (SDB) Offset (Byte) Field Description 0 Internal Temp Source or Sink’s internal temperature in °C  0 = feature not supported  1 = temperature is less than 2°C.  2-255 = temperature in °C. 1 Present Input Bit Description 0 Reserved and Shall be set to zero 1 External Power when set 2 External Power AC/DC (Valid when Bit 1 set)  0: DC  1: AC Reserved when Bit 1 is zero 3 Internal Power from Battery when set 4 Internal Power from non-Battery power source when set 5...7 Reserved and Shall be set to zero 2 Present Battery Input When Present Input field bit 3 set Shall contain the bit corresponding to the Battery or Batteries providing power:  Upper nibble = Hot Swappable Battery (b7…4)  Lower nibble = Fixed Battery (b3…0) When Present Input field bit 3 is not set this field is Reserved and Shall be set to zero. Extended Header Data Size = 7 SDB (7-byte block) Page 222 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 3 Event Flags Bit Flag Description 0 Reserved and Shall be set to zero 1 OCP Event OCP event when set 2 OTP Event OTP event when set 3 OVP Event OVP event when set 4 CL/CV Mode In PPS Mode only: CL mode when set, CV mode when cleared 5...7 Reserved and Shall be set to zero 4 Temperature Status Bit Description 0 Reserved and Shall be set to zero 1...2  00 – Not Supported.  01 – Normal  10 – Warning  11 – Over temperature 3...7 Reserved and Shall be set to zero 5 Power Status Bit Description 0 Reserved and Shall be set to zero 1 Source power limited due to cable supported current 2 Source power limited due to insufficient power available while sourcing other ports 3 Source power limited due to insufficient external power 4 Source power limited due to Event Flags in place (Event Flags must also be set) 5 Source power limited due to temperature 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 223 6.5.2.1.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of a portion of the Source or Sink. 6.5.2.1.2 Present Input Field The Present Input field indicates which supplies are presently powering the Source or Sink. The following bits are defined:  Bit 1: indicates that an external power source is present.  Bit 2: indicates whether the external unconstrained power source is AC or DC.  Bit 3: indicates that power is being provided from Battery.  Bit4: indicates an alternative internal source of power that is not a Battery. 6.5.2.1.3 Present Battery Input Field The Present Battery Input field indicates which Battery or Batteries are presently supplying power to the Source or Sink. The Present Battery Input field is only Valid when the Present Input field indicates that there is Internal Power from Battery. The upper nibble of the field indicates which Hot Swappable Battery/Batteries are supplying power with bit 4 in upper nibble corresponding to Battery 4 and bit 7 in the upper nibble corresponding to Battery 7 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). The lower nibble of the field indicates which Fixed Battery/Batteries are supplying power with bit 0 in lower nibble corresponding to Battery 0 and bit 3 in the lower nibble corresponding to Battery 3 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). 6 Power State Change Bit Description 0...2 New Power State Value Description 0 Status not supported 1 S0 2 Modern Standby 3 S3 4 S4 5 S5 (Off with battery, wake events supported) 6 G3 (Off with no battery, wake events not supported) 7 Reserved and Shall be set to zero 3...5 New Power State indicator Value Description 0 Off LED 1 On LED 2 Blinking LED 3 Breathing LED 4...7 Reserved and Shall be set to zero 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Page 224 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.1.4 Event Flags Field The Event Flags field returns event flags. The OTP, OVP and OCP event flags Shall be set when there is an event and Shall only be cleared when read with the Get_Status Message. When the OTP Event flag is set the Temperature Status field Shall also be set to over temperature. The CL/CV Mode flag is only Valid when operating as a Programmable Power Supply and Shall be Ignored otherwise. When the Source is operating as a Programmable Power Supply the CL/CV Mode flag Shall be set when operating in Current Limit mode (CL) and Shall be cleared when operating in Constant Voltage mode (CV). 6.5.2.1.5 Temperature Status Field The Temperature Status field returns the current temperature status of the device either: normal, warning or over temperature. When the Temperature Status field is set to over temperature the OTP Event flag Shall also be set. 6.5.2.1.6 Power Status Field The Power Status field indicates the current status of a Source. A non-zero return of the field indicates Advertised Source power is being reduced for either:  The cable does not support the full Source current.  The Source is supplying power to other ports and is unable to provide its full power.  The external power to the Source is insufficient to support full power.  An Event has occurred that is causing the Source to reduce its Advertised power. A Sink Shall set this field to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 225 6.5.2.1.7 Power state change The Power State Change field contains two status bytes; the New Power State and New Power State indicator status bytes. 6.5.2.1.7.1 New power state The New Power State status byte indicates a power state change to one of the specified power states. Any device that supports the ACPI standard system power states Shall use the ACPI states. For devices that do not support the ACPI power states, the following mapping Should be used:  High power (on) state -> S0  Sleep state -> S3  Low power (off) state -> S5 or G3 6.5.2.1.7.2 New power state indicator The New Power State indicator status byte defines the host's desired indicator for the specified power state. This indicator allows several possibilities for predefined behaviors that the host can specify to indicate its system power state to the user via the downstream device. The New Power State indicator is a "best effort" indicator. If the device cannot provide the requested indicator, then it provides the best indicator that it can. If a Breathing indicator cannot be provided, then a Blinking indicator Should be provided. If a Blinking indicator cannot be provided, then a constant on indicator Should be provided. New Power State indicators in decreasing precedence:  Breathing  Blinking  Constant on  No indicator Page 226 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.2 SOP'/SOP'' Status Message A Status Message, sent in response to a Get_Status Message to SOP’ or SOP’’, enables a Source or Sink to get the present status of the Cable's Cable Plug(s). Typically, a Get_Status Message will be used by the USB Host and/or USB Device to manage the Cable's Cable Plug(s) temperature. The Status Message returns a 2-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.39, "SOP'/SOP'' Status Message" and Table 6.56, "“SOP’/SOP’’ Status Data Block (SPDB)”". Passive Cable Plugs Shall Not indicate Thermal Shutdown. Figure 6.39 SOP'/SOP'' Status Message 6.5.2.2.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of the plug in °C. The internal temperature Shall be monotonic. The Cable Plug Shall report its internal temperature every tACTempUpdate. 6.5.2.2.2 Thermal Shutdown Field The Flags flag Shall also be set when the plug's internal temperature exceeds the Internal Maximum Temperature reported in the Active Cable VDO. Once this bit has been set, it Shall remain set and the plug Shall remain in Thermal Shutdown until there is a Hard Reset or the Active Cable's power is removed. The Thermal Shutdown flag Shall Not be cleared by a Cable Reset. Table 6.56 “SOP’/SOP’’ Status Data Block (SPDB)” Offset (Byte) Field Value Description 0 Internal Temp Unsigned Int Cable Plug’s internal temperature in °C.  0 = feature not supported  1 = temperature is less than 2°C.  2…255 = temperature in °C. 1 Flags Bit Field Bit Description 0 Thermal Shutdown 1...7 Reserved and Shall be set to zero Extended Header Data Size = 2 SPDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 227 6.5.3 Get_Battery_Cap Message The Get_Battery_Cap (Get Battery Capabilities) Message is used to request the capability of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Capabilities Message (see Section 6.5.5, "Battery_Capabilities Message") containing a Battery Capabilities Data Block (BCDB) for the targeted Battery. The Get_Battery_Cap Message contains a 1-byte Get Battery Cap Data Block (GBCDB), whose format Shall be as shown in Figure 6.40, "Get_Battery_Cap Message" and Table 6.57, "Get Battery Cap Data Block (GBCDB)". This block defines for which Battery the request is being made. The Data Size field in the Get_Battery_Cap Message Shall be set to 1. Figure 6.40 Get_Battery_Cap Message 6.5.4 Get_Battery_Status Message The Get_Battery_Status (Get Battery Status) Message is used to request the status of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Status Message (see Section 6.4.5, "Battery_Status Message") containing a Battery Status Data Object (BSDO) for the targeted Battery. The Get_Battery_Status Message contains a 1-byte Get Battery Status Data Block (GBSDB) whose format Shall be as shown in Figure 6.41, "Get_Battery_Status Message" and Table 6.58, "Get Battery Status Data Block (GBSDB)". This block contains details of the requested Battery. The Data Size field in the Get_Battery_Status Message Shall be set to 1. Figure 6.41 Get_Battery_Status Message Table 6.57 Get Battery Cap Data Block (GBCDB) Offset Field Description 0 Battery Cap Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Table 6.58 Get Battery Status Data Block (GBSDB) Offset Field Description 0 Battery Status Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Extended Header Data Size = 1 GBCDB Extended Header Data Size = 1 GBSDB Page 228 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.5 Battery_Capabilities Message The Battery_Capabilities Message is sent in response to a Get_Battery_Cap Message. The Battery_Capabilities Message contains one Battery Capability Data Block (BCDB) for one of the Batteries its supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BCDB Shall correspond to the Battery requested in the Battery Cap Ref field contained in the Get_Battery_Cap Message. The Battery_Capabilities Message returns a 9-byte BCDB whose format Shall be as shown in Figure 6.42, "Battery_Capabilities Message" and Table 6.59, "Battery Capability Data Block (BCDB)”". Figure 6.42 Battery_Capabilities Message 6.5.5.1 Vendor ID (VID) The VID field Shall contain the manufacturer VID associated with the Battery, as assigned by the USB-IF, or 0xFFFF in the case that no such VID exists. If the Battery Cap Ref field in the Get_Battery_Cap Message is Invalid, the VID field Shall be 0xFFFF. 6.5.5.2 Product ID (PID) The following rules apply to the PID field. When the VID: Table 6.59 Battery Capability Data Block (BCDB)” Offset (Byte) Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Battery Design Capacity Battery’s design capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = design capacity unknown 6 Battery Last Full Charge Capacity Battery’s last full charge capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = last full charge capacity unknown 8 Battery Type Bit Field Description 0 Invalid Battery Reference Invalid Battery reference when set. 1...7 --- Reserved Extended Header Data Size = 9 BCDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 229  Belongs to the Battery vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  Belongs to the Device vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor.  Is 0xFFFF the PID field Shall be set to 0x0000. 6.5.5.3 Battery Design Capacity Field The Battery Design Capacity field Shall return the Battery's design capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Design Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Design Capacity field Shall be set to 0xFFFF. 6.5.5.4 Battery Last Full Charge Capacity Field The Battery Last Full Charge Capacity field Shall contain the Battery's last full charge capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Last Full Charge Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Last Full Charge Capacity field Shall be set to 0xFFFF. 6.5.5.5 Battery Type Field The Battery Type field is used to report additional information about the Battery's Capabilities. 6.5.5.5.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Cap Message contains a reference to a Battery that does not exist. Page 230 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.6 Get_Manufacturer_Info Message The Get_Manufacturer_Info (Get Manufacturer Info) Message is sent by a Port to request manufacturer specific information relating to its Port Partner, Cable Plug or of a Battery behind a Port. The Port Shall respond by returning a Manufacturer_Info Message (Section 6.5.7, "Manufacturer_Info Message") containing a Manufacturer Info Data Block (MIDB). Support for this feature by the Cable Plug is Optional Normative. The Get_Manufacturer_Info Message contains a 2-byte Get Manufacturer Info Data Block (GMIDB). This block defines whether it is the Device or Battery manufacturer information being requested and for which Battery the request is being made. The Get_Manufacturer_Info Message returns a GMIDB whose format Shall be as shown in Figure 6.43, "Get_Manufacturer_Info Message" and Table 6.60, "Get Manufacturer Info Data Block (GMIDB)". Figure 6.43 Get_Manufacturer_Info Message Table 6.60 Get Manufacturer Info Data Block (GMIDB) Offset Field Description 0 Manufacturer Info Target  0: Port/Cable Plug  1: Battery  255…2: Reserved and Shall Not be used. 1 Manufacturer Info Ref If the Manufacturer Info Target field is Battery (01b) the Manufacturer Info Ref field Shall contain the Battery number reference which is the number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries. Otherwise, this field is Reserved and Shall be set to zero. Extended Header Data Size = 2 GMIDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 231 6.5.7 Manufacturer_Info Message The Manufacturer_Info Message Shall be sent in response to a Get_Manufacturer_Info Message. The Manufacturer_Info Message contains the USB VID and the Vendor's PID to identify the device or Battery and the device or Battery's manufacturer byte array in a variable length Data Block of up to MaxExtendedMsgLegacyLen. The Manufacturer_Info Message returns a Manufacturer Info Data Block (MIDB) whose format Shall be as shown in Figure 6.44, "Manufacturer_Info Message" and Table 6.61, "Manufacturer Info Data Block (MIDB)". Figure 6.44 Manufacturer_Info Message 6.5.7.1 Vendor ID (VID) If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the VID field Shall contain:  The manufacturer's VID associated with the Port/Cable Plug, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Device that has a USB data interface, the Device Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery, the VID field Shall contain:  The manufacturer VID associated with the Battery specified, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message:  Is Invalid, this VID field Shall be 0xFFFF.  Is Battery (01b) and the Manufacturer Info Ref field is Invalid, the VID field Shall be 0xFFFF. 6.5.7.2 Product ID (PID) If the VID is 0xFFFF, the PID field Shall contain 0x0000. Otherwise: Table 6.61 Manufacturer Info Data Block (MIDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Manufacturer String Vendor defined null terminated string of 0…21 characters. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string “Not Supported”. Extended Header Data Size = 5..26 MIDB Page 232 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the PID field Shall contain the device's 16-bit product identifier designated by the device vendor.  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery:  And the VID belongs to the Battery vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  And the VID belongs to the Device vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor. 6.5.7.3 Manufacturer String The Manufacturer String field Shall contain the device’s or Battery's manufacturer string as defined by the vendor. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string "Not Supported". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 233 6.5.8 Security Messages The authentication process between Port Partners or a Port and Cable Plug is fully described in [USBTypeCAuthentication 1.0]. This specification describes two Extended Messages used by the authentication process when applied to PD. In the authentication process described in [USBTypeCAuthentication 1.0] there are three basic exchanges that serve to:  Get the Port or Cable Plug's certificates.  Get the Port or Cable Plug's digest.  Challenge the Port Partner or Cable Plug. Certificates are used to convey information, attested to by a signer, which attests to the Port Partner's or Cable Plug's authenticity. The Port's or Cable Plug's certificates are needed when a Port encounters a Port Partner or Cable Plug it has not been Attached to before. To minimize calculations after the initial Attachment, a Port can also use a digest consisting of hashes of the certificates rather than the certificates themselves. Once the Port has the certificates and has calculated the hashes, it stores the hashes and uses the digest in future exchanges. After the Port gets the certificates or digest, it challenges its Port Partner or the Cable Plug to detect replay attacks. For further details refer to [USBTypeCAuthentication 1.0]. 6.5.8.1 Security_Request The Security_Request Message is used by a Port to pass a security data structure to its Port Partner or a Cable Plug. The Security_Request Message contains a Security Request Data Block (SRQDB) whose format Shall be as shown in Figure 6.45, "Security_Request Message". The contents of the SRQDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.45 Security_Request Message 6.5.8.2 Security_Response The Security_Response Message is used by a Port or Cable Plug to pass a security data structure to the Port that sent the Security_Request Message. The Security_Response Message contains a Security Response Data Block (SRPDB) whose format Shall be as shown in Figure 6.46, "Security_Response Message". The contents of the SRPDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.46 Security_Response Message Extended Header Data Size = 4..260 SRQDB Extended Header Data Size = 4..260 SRPDB Page 234 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.9 Firmware Update Messages The firmware update process between Port Partners or a Port and Cable Plug is fully described in [USBPDFirmwareUpdate 1.0]. This specification describes two Extended Messages used by the firmware update process when applied to PD. 6.5.9.1 Firmware_Update_Request The Firmware_Update_Request Message is used by a Port to pass a firmware update data structure to its Port Partner or a Cable Plug. The Firmware_Update_Request Message contains a Firmware Update Request Data Block (FRQDB) whose format Shall be as shown in Figure 6.47, "Firmware_Update_Request Message". The contents of the FRQDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.47 Firmware_Update_Request Message 6.5.9.2 Firmware_Update_Response The Firmware_Update_Response Message is used by a Port or Cable Plug to pass a firmware update data structure to the Port that sent the Firmware_Update_Request Message. The Firmware_Update_Response Message contains a Firmware Update Response Data Block (FRPDB) whose format Shall be as shown in Figure 6.48, "Firmware_Update_Response Message". The contents of the FRPDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.48 Firmware_Update_Response Message Extended Header Data Size = 4..260 FRQDB Extended Header Data Size = 4..260 FRPDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 235 6.5.10 PPS_Status Message The PPS_Status Message Shall be sent in response to a Get_PPS_Status Message. The PPS_Status Message enables a Sink to query the Source to get additional information about its operational state. The Get_PPS_Status Message and the PPS_Status Message Shall only be supported when the Alert Message is also supported. The PPS_Status Message Shall return a 4-byte PPS Status Data Block (PPSSDB) whose format Shall be as shown in Figure 6.49, "PPS_Status Message" and Table 6.62, "PPS Status Data Block (PPSSDB)". Figure 6.49 PPS_Status Message 6.5.10.1 Output Voltage Field The Output Voltage field Shall return the Source's output voltage at the time of the request. The output voltage is measured either at the Source's receptacle or, if the Source has a captive cable, where the voltage is applied to the cable. The measurement accuracy Shall be +/-3% rounded to the nearest 20mV in SPR PPS Mode. If the Source does not support the Output Voltage field, the field Shall be set to 0xFFFF. 6.5.10.2 Output Current Field The Output Current field Shall return the Source's output current at the time of the request measured at the Source's receptacle. The measurement accuracy Shall be +/-150mA. If the Source does not support the Output Current field, the field Shall be set to 0xFF. Table 6.62 PPS Status Data Block (PPSSDB) Offset (Byte) Field Description 0 Output Voltage 2 Source’s output voltage in 20mV units. When set to 0xFFFF, the Source does not support this field. 2 Output Current 1 Source’s output current in 50mA units. When set to 0xFF, the Source does not support this field. 3 Real Time Flags Bit Description 0 Reserved and Shall be set to zero 1...2 PTF  PTF: 00 – Not Supported  PTF: 01 – Normal  PTF: 10 – Warning  PTF: 11 – Over temperature 3 OMF OMF (Operating Mode Flag) is set when operating in Current Limit mode and cleared when operating in Constant Voltage mode. 4...7 Reserved and Shall be set to zero Extended Header Data Size = 4 PPSSDB (4-byte Data Block) Page 236 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.10.3 Real Time Flags Field Real Time flags provide a real-time indication of the Source's operating state:  The PTF (Present Temperature Flag) Shall provide a real-time indication of the Source's internal thermal status. If the PTF is not supported, it will be set to zero:  Normal indicates that the Source is operating within its normal thermal envelope.  Warning indicates that the Source is over-heating but is not in imminent danger of shutting down.  Over Temperature indicates that the Source is over heated and will shut down soon or has already shutdown and has sent the OTP Event flag in an Alert Message.  The OMF (Operating Mode Flag) Shall provide a real-time indication of the SPR PPS Source's operating mode. When set, the Source is operating in Current Limit mode; when cleared it is operating Constant Voltage mode. This bit Shall be set to zero when not in SPR PPS Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 237 6.5.11 Country_Codes Message The Country_Codes Message Shall be sent in response to a Get_Country_Codes Message. The Country_Codes Message enables a Port to query its Port Partner to get a list of alpha-2 country codes as defined in [ISO 3166] for which the Port Partner has country specific information. The Country_Codes Message Shall contain a 4…26-byte Country Code Data Block (CCDB) whose format Shall be as shown in Figure 6.50, "Country_Codes Message" and Table 6.63, "Country Codes Data Block (CCDB)". Figure 6.50 Country_Codes Message 6.5.11.1 Country Code Field The Country Code field Shall contain Length Country Codes in the Alpha-2 Country Code defined by [ISO 3166]. Table 6.63 Country Codes Data Block (CCDB) Offset Field Description 0 Length Number of country codes in the Message 1 Reserved Shall be set to zero. 2... Length * 2n Country Code Offset Field Description 2 1st Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 3 Second character of the Alpha-2 Country Code defined by [ISO 3166] 4 2nd Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 5 Second character of the Alpha-2 Country Code defined by [ISO 3166] … Length * 2n nth Country Code Extended Header Data Size = 4-26 CCDB (4-26 byte Data Block) Page 238 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.12 Country_Info Message The Country_Info Message Shall be sent in response to a Get_Country_Info Message. The Country_Info Message enables a Port to get additional country specific information from its Port Partner. The Country_Info Message Shall contain a 4…26-byte Country Info Data Block (CIDB) whose format Shall be as shown in Figure 6.51, "Country_Info Message" and Table 6.64, "Country Info Data Block (CIDB)". Figure 6.51 Country_Info Message 6.5.12.1 Country Code Field The Country Code field Shall contain the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 6.5.12.2 Country Specific Data Field The Country Specific Data field Shall contain content defined by and formatted in a manner determined by an official agency of the country indicated in the Country Code field. If the Country Code field in the Get_Country_Info Message is unrecognized then Country Specific Data field Shall return the null terminated ASCII text string "Unsupported Code". Table 6.64 Country Info Data Block (CIDB) Offset Field Size 0 Country Code First character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 1 Second character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message 2…3 Reserved Shall be set to zero. 4 Country Specific Data 1…22 bytes of content defined by the country’s authority. Extended Header Data Size = 4-26 CIDB (4-26 byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 239 6.5.13 Sink_Capabilities_Extended Message The Sink_Capabilities_Extended Message Shall be sent in response to a Get_Sink_Cap_Extended Message. The Sink_Capabilities_Extended Message enables a Sink or a DRP to inform the Source about its Capabilities as a Sink. The Sink_Capabilities_Extended Message Shall return a 24-byte Sink Capabilities Extended Data Block (SKEDB) whose format Shall be as shown in Figure 6.52, "Sink_Capabilities_Extended Message" and Table 6.65, "Sink Capabilities Extended Data Block (SKEDB)". Figure 6.52 Sink_Capabilities_Extended Message Table 6.65 Sink Capabilities Extended Data Block (SKEDB) Offset (Byte) Field Size (Bytes) Type Description 0 VID 2 Numeric Vendor ID (assigned by the USB-IF) 2 PID 2 Numeric Product ID (assigned by the manufacturer) 4 XID 4 Numeric Value provided by the USB-IF assigned to the product 8 FW Version 1 Numeric Firmware version number 9 HW Version 1 Numeric Hardware version number 10 SKEDB Version 1 Numeric SKEDB Version (not the specification Version):  Version 1.0 = 1 Values 0 and 2-255 are Reserved and Shall Not be used. 11 Load Step 1 Bit Field Bit Description 0...1  00b: 150mA/μs Load Step (default)  01b: 500mA/μs Load Step 11b…10b: Reserved and Shall Not be used. 2...7 Reserved and Shall be set to zero 12 Sink Load Characteristics 2 Bit Field Bit Description 0...4 Percent overload in 10% increments. Values higher than 25 (11001b) are clipped to 250%. 00000b is the default. 5...10 Overload period in 20ms when bits 0...4 non-zero. 1...14 Duty cycle in 5% increments when bits 0...4 are non-zero. 15 Can tolerate VBUS voltage droop 14 Compliance 1 Bit Field Bit Description 0 Requires LPS Source when set 1 Requires PS1 Source when set 2 Requires PS2 Source when set 3...7 Reserved and Shall be set to zero Extended Header Data Size = 24 SKEDB (24 byte Data Block) Page 240 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Sink's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.13.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Sink's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 15 Touch Temp 1 Value Temperature conforms to:  0 = Not applicable  1 = [IEC 60950-1] (default)  2 = [IEC 62368-1] TS1  3 = [IEC 62368-1] TS2 Note: All other values Reserved 16 Battery Info 1 Byte Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 17 Sink Modes 1 Bit Field Bit Description 0 PPS charging supported 1 VBUS powered 2 AC Supply powered 3 Battery powered 4 Battery essentially unlimited 5 AVS Support 6...7 Reserved and Shall be set to zero 18 SPR Sink Minimum PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 7 Reserved and Shall be set to zero 19 SPR Sink Operational PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its normal functionality. 7 Reserved and Shall be set to zero 20 SPR Sink Maximum PDP 1 Byte Bit Description 0...6 The maximum PDP the Sink will ever request. 7 Reserved and Shall be set to zero 21 EPR Sink Minimum PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 22 EPR Sink Operational PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its normal functionality. 23 EPR Sink Maximum PDP 1 Byte The maximum PDP that the EPR Sink will ever request. Table 6.65 Sink Capabilities Extended Data Block (SKEDB) (Continued) Offset (Byte) Field Size (Bytes) Type Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 241 6.5.13.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.13.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.13.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.13.6 SKEDB Version Field The SKEDB Version field contains the version level of the SKEDB. Currently only Version 1 is defined. 6.5.13.7 Load Step Field The Load Step field contains bits indicating the Load Step Slew Rate and Magnitude that this Sink prefers. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.13.8 Sink Load Characteristics Field The Sink Shall report its preferred load characteristics in the Sink Load Characteristics field. Regardless of this value, in operation its load Shall Not exceed the Capabilities reported in the Source_Capabilities_Extended Message. 6.5.13.9 Compliance Field The Compliance field Shall contain the types of Sources the Sink has been tested and certified with (see Section 7.1.12.3, "Compliance Field"). 6.5.13.10 Touch Temp The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Sink's enclosure. Safety limits for the Sink's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Sink May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.13.11 Battery Info The Battery Info field Shall report the number of Fixed Batteries and Hot Swappable Battery slots the Sink supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. The information reported in the Battery Info field Shall match that reported in the Number of Batteries/Battery Slots field of the Source_Capabilities_Extended Message. A Sink Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 242 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.12 Sink Modes The Sink Modes bit field Shall identify the charging Capabilities and the power sources that can be used by the Sink. When bit 0 is set, the Sink has the ability to use a PPS Source for fast charging. The source of power a Sink can use:  When bit 1 is set, the Sink has the ability to be sourced by VBUS.  When bit 2 is set, the Sink has the ability to be sourced by an AC Supply.  When bit 3 is set, the Sink has the ability to be sourced by a Battery.  When bit 4 is set, the Sink has the ability to be sourced by a Battery with essentially infinite energy (e.g., a car battery). Bits 1-4 May be set independently of one another. The combination indicates what sources of power the Sink can utilize. For example, some Sinks are only powered by a Battery (e.g., an automobile battery) rather than the more common AC Supply and some Sinks are only powered from VBUS or VCONN. When bit 5 is set, the Sink has the ability to support AVS. 6.5.13.13 SPR Sink Minimum PDP The SPR Sink Minimum PDP field Shall contain the minimum power Source PDP needed by the Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The SPR Sink Minimum PDP field Shall be less than or equal to the SPR Sink Operational PDP. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of SPR Sink Minimum PDP could be:  The minimum power a wireless Charger would require in order to detect, and deliver the minimum required amount of power to the attached device.  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device 6.5.13.14 SPR Sink Operational PDP The SPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The SPR Sink Operational PDP field Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), the SPR Sink Operational PDP field Shall correspond to the PDP Rating of the Charger shipped with the Sink or the recommended Charger's PDP Rating. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set the SPR Sink Minimum PDP field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 243 6.5.13.15 SPR Sink Maximum PDP The SPR Sink Maximum PDP field Shall contain the highest PDP the Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The SPR Sink Maximum PDP field Shall Not be less than the SPR Sink Operational PDP field, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. 6.5.13.16 EPR Sink Minimum PDP The EPR Sink Minimum PDP field Shall contain the Source PDP needed by an EPR Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery, if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The EPR Sink Minimum PDP field Shall be less than or equal to the EPR Sink Operational PDP field value. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of EPR Sink Minimum PDP could be:  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device. Note: EPR Sink Minimum PDP can be the same as its SPR Sink Minimum PDP. 6.5.13.17 EPR Sink Operational PDP The EPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of EPR Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The EPR Sink Operational PDP Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), it Shall correspond to the PDP Rating of the Charger shipped with the EPR Sink or the recommended Charger's PDP Rating. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. 6.5.13.18 EPR Sink Maximum PDP The EPR Sink Maximum PDP field Shall be highest PDP the EPR Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The EPR Sink Maximum PDP field Shall Not be less than the EPR Sink Operational PDP, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. Page 244 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.14 Extended_Control Message The Extended_Control Message extends the Control Message space. The Extended_Control Message includes one byte of data. The Extended_Control Message Shall be as shown in Figure 6.53, "Extended_Control Message" and Table 6.66, "Extended Control Data Block (ECDB)". Figure 6.53 Extended_Control Message The Extended_Control Message types are specified in the Type field of the ECDB and are listed in Table 6.67, "Extended Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets. 6.5.14.1 EPR_Get_Source_Cap Message The EPR_Get_Source_Cap (EPR Get Source Capabilities) Message Shall only be sent by a Port capable of operating as a Sink and that supports EPR Mode to request the Source Capabilities and Dual-Role Power capability of its Port Partner. A Port that can operate as an EPR Source Shall respond by returning an EPR_Source_Capabilities Message (see Section 6.5.15.2, "EPR_Source_Capabilities Message"). A Port that does not support EPR Mode as a Source Shall return the Not_Supported Message. An EPR Capable Sink Port that is operating in SPR Mode Shall treat the EPR_Source_Capabilities Message as informational only and Shall Not respond with an EPR_Request Message. 6.5.14.2 EPR_Get_Sink_Cap Message The EPR_Get_Sink_Cap (EPR Get Sink Capabilities) Message Shall only be sent by a Port capable of operating as a Source and that supports EPR Mode to request the Sink Capabilities and Dual-Role Power capability of its Port Partner. A Port that is EPR Capable operating as a Sink Shall respond by returning an EPR_Sink_Capabilities Message (see Section 6.5.15.3, "EPR_Sink_Capabilities Message"). A Port that does not support EPR Mode as a Sink Shall return the Not_Supported Message. Table 6.66 Extended Control Data Block (ECDB) Offset Field Value Description 0 Type Unsigned Int Extended Control Message Type 1 Data Byte Shall be set to zero when not used. Table 6.67 Extended Control Message Types Type Data Message Type Sent by Description Valid Start of Packet 0 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 Not used EPR_Get_Source_Cap Sink or DRP See Section 6.5.14.1 SOP only 2 Not used EPR_Get_Sink_Cap Source or DRP See Section 6.5.14.2 SOP only 3 Not used EPR_KeepAlive Sink See Section 6.5.14.3 SOP only 4 Not Used EPR_KeepAlive_Ack Source See Section 6.5.14.4 SOP only 5...255 Reserved All values not explicitly defined are Reserved and Shall Not be used. Extended Header Data Size = 2 ECDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 245 6.5.14.3 EPR_KeepAlive Message The EPR_KeepAlive Message May be sent by a Sink operating in EPR Mode to meet the requirement for periodic traffic. The Source operating on EPR Mode responds by returning an EPR_KeepAlive_Ack Message to the Sink. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.14.4 EPR_KeepAlive_Ack Message The EPR_KeepAlive_Ack Message Shall be sent by a Source operating in EPR Mode in response to an EPR_KeepAlive Message. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.15 EPR Capabilities Message The EPR Capabilities Message is an Extended Capabilities Message made of Power Data Objects (PDO) defined in Section 6.4.1, "Capabilities Message". It is used to form EPR_Source_Capabilities Messages and EPR_Sink_Capabilities Messages. Sources expose their EPR power Capabilities by sending an EPR_Source_Capabilities Message. Sinks expose their EPR power requirements by returning an EPR_Sink_Capabilities Message when requested. Both are composed of a number of 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). An EPR Capabilities Message Shall have a 5V Fixed Supply PDO containing the sending Port's information in the first object position followed by up to 10 additional PDOs. 6.5.15.1 EPR Capabilities Message Construction The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. See Figure 6.54, "Mapping SPR Capabilities to EPR Capabilities". Figure 6.54 Mapping SPR Capabilities to EPR Capabilities Power Data Objects in the EPR Capabilities Messages Shall be sent in the following order: 1) The SPR (A)PDOs as reported in the SPR Capabilities Message. The Number of Data Objects field in the Message Header of the EPR Capabilities Message is the same as the Number of Data Objects field in the Message Header of the SPR Capabilities Message. 2) If the SPR Capabilities Message contains fewer than 7 PDOs, the unused Data Objects Shall be zero filled. 3) The EPR (A)PDOs as defined in Section 6.4.1, "Capabilities Message" Shall start at Data Object position 8 and Shall be sent in the following order: a) Fixed Supply PDOs that offer 28V, 36V or 48V, if present, Shall be sent in voltage order; lowest to highest. b) One EPR AVS APDO Shall be sent. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 EPR PDO 8 EPR PDO 9 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 PDOs > 20V2 001b 010b 011b 100b 101b 110b 111b 1000b 1001b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b EPR PDO 10 EPR PDO 11 1010b 1011b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. 2) See Section 10 “Power Rules” for rules, on which EPR (A)PDOs are allowed be used for a given PDP. Page 246 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.15.2 EPR_Source_Capabilities Message The EPR_Source_Capabilities is an EPR Capabilities Message containing a list of Power Data Objects that the EPR Source is capable of supplying. It is sent by an EPR Source in order to convey its Capabilities to a Sink. An EPR Source Shall send the EPR_Source_Capabilities Message:  When entering EPR Mode  While in EPR Modes when its Capabilities change  In response to an EPR_Get_Source_Cap Message  After a Soft Reset while in EPR Mode An EPR Sink operating in EPR Mode Shall evaluate every EPR_Source_Capabilities Message it receives and Shall respond with a EPR_Request Message. If its power consumption exceeds the Source Capabilities, it Shall Re- negotiate so as not to exceed the Source's most recently Advertised Source Capabilities. While operating in SPR Mode, an EPR Sink receiving an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Messages Shall Not respond with an EPR_Request Message. The (A)PDOs in an EPR_Source_Capabilities Message Shall only be requested using the EPR_Request Message and only when in EPR Mode. When Source wants to exit EPR Mode, if not already in power contract with an SPR (A)PDO, it Shall send an EPR_Source_Capabilities Message with no EPR (A)PDOs (i.e. seven SPR (A)PDOs including any zero padded ones). See Figure 6.55, "EPR_Source_Capabilities message with no EPR PDOs". Figure 6.55 EPR_Source_Capabilities message with no EPR PDOs 6.5.15.3 EPR_Sink_Capabilities Message The EPR_Sink_Capabilities is an EPR Capabilities Message that contains a list of Power Data Objects that the EPR Sink requires to operate. It is sent by an EPR Sink in order to convey its power requirements to an EPR Source. The EPR Sink Shall only send the EPR_Sink_Capabilities Message in response to an EPR_Get_Sink_Cap Message. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 001b 010b 011b 100b 101b 110b 111b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 247 6.5.16 Vendor_Defined_Extended Message The Vendor_Defined_Extended Message (VDEM) is provided to allow vendors to exchange information outside of that defined by this specification using the Extended Message format. A Vendor_Defined_Extended Message Shall consist of at least one Vendor Data Object, the VDM Header, and May contain up to a maximum of 256 additional data bytes. To ensure vendor uniqueness of Vendor_Defined_Extended Messages, all Vendor_Defined_Extended Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. A VDEM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined_Extended Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. For example, a Vendor_Defined_Extended Message could be used to enable the Source to offer additional power via a Source_Capabilities Message. Vendor_Defined_Extended Messages Shall Not be used where equivalent functionality is contained in the PD Specification e.g., authentication or firmware update. The Message format Shall be as shown in Figure 6.56, "Vendor_Defined_Extended Message". Figure 6.56 Vendor_Defined_Extended Message The VDM Header Shall be the first 4-bytes in a Vendor Defined Extended Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. The VDM Header in the VDEM Shall follow the Unstructured VDM Header format as defined in Section 6.4.4.1, "Unstructured VDM". VDEMs Shall only be sent and received after an Explicit Contract has been established. A VDEM AMS Shall Not interrupt any other PD AMS. The VDEM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the SVID. The Port Partners and Cable Plugs Shall exit any states entered using a VDEM according to the rules defined in Section 6.4.4.3.4, "Enter Mode Command". The following rules apply to the use of VDEM Messages:  VDEMs Shall Not be initiated or responded to under any other circumstances than the following:  VDEMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract VDEMs Shall Not be sent and Shall be Ignored if received.  Cable Plugs Shall Not initiate VDEMs. Extended Header Data Size = 4...260 VDM Header VDEDB (0...256-byte Data Block) Page 248 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  VDEMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can VDEMs be sent or received. The Active Mode and the associated VDEMs Shall use the same SVID.  VDEMs May be used with SOP* Packets.  When a DFP or UFP does not support VDEMs or does not recognize the VID it Shall return a Not_Supported Message. Note: Usage of VDEMs with Chunking is not recommended since this is less efficient than using Unstructured VDMs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 249 6.6 Timers All the following timers are defined in terms of bits on the bus regardless of where they are implemented in terms of the logical architecture. This is to ensure a fixed reference for the starting and stopping of timers. It is left to the implementer to ensure that this timing is observed in a real system. 6.6.1 CRCReceiveTimer The CRCReceiveTimer Shall be used by the sender's Protocol Layer to ensure that a Message has not been lost. Failure to receive an acknowledgment of a Message (a GoodCRC Message) whether caused by a bad GoodCRC Message on the receiving end or by a garbled Message within tReceive is detected when the CRCReceiveTimer expires. The sender's Protocol Layer response when a CRCReceiveTimer expires Shall be to retry nRetryCount times. Note: Cable Plugs do not retry Messages and large Extended Messages that are not Chunked are not retried (see Section 6.7.2, "Retry Counter"). Sending of the Preamble corresponding to the retried Message Shall start within tRetry of the CRCReceiveTimer expiring. The CRCReceiveTimer Shall be started when the last bit of the Message EOP has been transmitted by the PHY Layer. The CRCReceiveTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer. The Protocol Layer receiving a Message Shall respond with a GoodCRC Message within tTransmit in order to ensure that the sender's CRCReceiveTimer does not expire. The tTransmit time Shall be measured from when the last bit of the Message EOP has been received by the PHY Layer until the first bit of the Preamble of the GoodCRC Message has been transmitted by the PHY Layer. 6.6.2 SenderResponseTimer The SenderResponseTimer Shall be used by the sender's Policy Engine to ensure that a Message requesting a response (e.g., Get_Source_Cap Message) is responded to within a bounded time of tSenderResponse. Failure to receive the expected response is detected when the SenderResponseTimer expires. For Extended Messages received as Chunks, the SenderResponseTimer will also be started and stopped by the Chunking Rx State Machine. See Section 8.3.3.1.1, "SenderResponseTimer State Diagram" for more details of the SenderResponseTimer operation. The Policy Engine's response when the SenderResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The SenderResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the Message requesting a response, has been received by the PHY Layer. The SenderResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected response Message, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tReceiverResponse in order to ensure that the sender's SenderResponseTimer does not expire. The tReceiverResponse time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the expected request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.3 Capability Timers Sources and Sinks use Capability Timers to determine Attachment of a PD Capable device. By periodically sending or requesting Capabilities, it is possible to determine PD device Attachment when a response is received. Page 250 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.3.1 SourceCapabilityTimer Prior to the First Explicit Contract a Source Shall use the SourceCapabilityTimer to periodically send out a Source_Capabilities Message every tTypeCSendSourceCap while:  The Port is Attached.  The Source is not in an active connection with a PD Sink Port. Whenever there is a SourceCapabilityTimer timeout the Source Shall send a Source_Capabilities Message. It Shall then re-initialize and restart the SourceCapabilityTimer. The SourceCapabilityTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer since a PD connection has been established. At this point, the Source waits for a Request Message or a response timeout. Note: The Source can also stop sending Source_Capabilities Message after nCapsCount Messages have been sent without a GoodCRC Message response (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.2, "Policy Engine Source Port State Diagram" for more details of when Source_Capabilities Messages are transmitted. 6.6.3.2 SinkWaitCapTimer The Sink Shall support the SinkWaitCapTimer. While in a Default Contract or an Implicit Contract when a Sink observes an absence of Source_Capabilities Messages, after VBUS is present, for a duration of tTypeCSinkWaitCap the Sink May issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter") or continue to operate at USB Type-C current. When a Sink, entering EPR Mode, observes an absence of EPR_Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to exit EPR Mode (see Section 6.4.10, "EPR_Mode Message"). When a Sink, exiting EPR Mode, observes an absence of Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.3, "Policy Engine Sink Port State Diagram" for more details of when the SinkWaitCapTimer is run. 6.6.3.3 tFirstSourceCap After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap a Source Shall send its first Source_Capabilities Message within tFirstSourceCap of VBUS reaching vSafe5V. After Soft Reset, a Source Shall send its first Source Capabilities Message within tFirstSourceCap after last bit of the GoodCRC Message EOP corresponding to Accept Message. This ensures that the Sink receives a Source Capabilities Message before the Sink's SinkWaitCapTimer expires. A Source entering EPR Mode Shall send its first EPR_Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded). A Source exiting EPR Mode Shall send its first Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 251 6.6.4 Wait Timers and Times 6.6.4.1 SinkRequestTimer The SinkRequestTimer is used to ensure that the time before the next Sink Request Message, after a Wait Message has been received from the Source in response to a Sink Request Message, is a minimum of tSinkRequest min (see Section 6.3.12, "Wait Message"). The SinkRequestTimer Shall be started when the EOP of a Wait Message has been received and Shall be stopped if any other Message is received or during a Hard Reset. The Sink Shall wait at least tSinkRequest, after receiving the EOP of a Wait Message sent in response to a Sink Request Message, before sending a new Request Message. Whenever there is a SinkRequestTimer timeout the Sink May send a Request Message. It Shall then re-initialize and restart the SinkRequestTimer. 6.6.4.2 tPRSwapWait The time before the next PR_Swap Message, after a Wait Message has been received in response to a PR_Swap Message is a minimum of tPRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tPRSwapWait after receiving the EOP of a Wait Message sent in response to a PR_Swap Message, before sending a new PR_Swap Message. 6.6.4.3 tDRSwapWait The time before the next DR_Swap Message, after a Wait Message has been received in response to a DR_Swap Message is a minimum of tDRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tDRSwapWait after receiving the EOP of a Wait Message sent in response to a DR_Swap Message, before sending a new DR_Swap Message. 6.6.4.4 tVCONNSwapWait The time before the next VCONN_Swap Message, after a Wait Message has been received in response to a VCONN_Swap Message is a minimum of tVCONNSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tVCONNSwapWait after receiving the EOP of a Wait Message sent in response to a VCONN_Swap Message, before sending a new VCONN_Swap Message. 6.6.4.5 tVCONNSwapDelayDFP The time delay for DFP after losing VCONN Source role due to an incoming VCONN Swap request from UFP and before sending the next VCONN_Swap Message. The DFP Shall wait at least tVCONNSwapDelayDFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.6 tVCONNSwapDelayUFP The time delay for UFP after losing VCONN Source role due to an incoming VCONN Swap request from DFP and before sending the next VCONN_Swap Message. The UFP Shall wait at least tVCONNSwapDelayUFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.7 tEnterUSBWait The time before the next Enter_USB Message, after a Wait Message has been received in response to a Enter_USB Message is a minimum of tEnterUSBWait min (see Section 6.3.12, "Wait Message"). The DFP Shall wait at least tEnterUSBWait after receiving the EOP of a Wait Message sent in response to an Enter_USB Message, before sending a new Enter_USB Message. 6.6.5 Power Supply Timers See Section 7.3, "Transitions" for diagrams showing the usage of the timers in this section. Page 252 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.5.1 PSTransitionTimer The PSTransitionTimer is used by the Policy Engine to timeout on a PS_RDY Message. It is started when a request for new Source Capabilities has been accepted and will timeout after tPSTransition if a PS_RDY Message has not been received. This condition leads to a Hard Reset and a return to USB Default Operation. The PSTransitionTimer relates to the time taken for the Source to transition from one voltage, or current level, to another (see Section 7.1, "Source Requirements"). The PSTransitionTimer Shall be started when the last bit of the GoodCRC Message EOP, corresponding to an Accept Message, has been transmitted by the PHY Layer. The PSTransitionTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer. 6.6.5.2 PSSourceOffTimer 6.6.5.2.1 Use during Power Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is currently acting as a Sink to timeout on a PS_RDY Message during a Power Role Swap AMS. This condition leads to USB Type-C Error Recovery. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Source the Sink can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this transmitted Accept Message, is received by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Sink the Source can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this received Accept Message, is transmitted by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the remote Dual-Role Power Device to stop supplying power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the remote Dual-Role Power Device within tPSSourceOff indicating this has occurred. 6.6.5.2.2 Use during Fast Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is the Initial Sink (currently providing vSafe5V) to timeout on a PS_RDY Message during a Fast Role Swap AMS. This condition leads to USB Type-C Error Recovery. When the FR_Swap Message request has been sent by the Initial Sink, the Initial Source Shall respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this Accept Message is received by the Initial Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the Initial Source to stop supplying power and for VBUS to revert to vSafe5V (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the Initial Source within tPSSourceOff indicating this has occurred. 6.6.5.3 PSSourceOnTimer 6.6.5.3.1 Use during Power Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Power Role Swap. This condition leads to USB Type-C Error Recovery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 253 The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer.  The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.5.3.2 Use during Fast Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Fast Role Swap. This condition leads to USB Type-C Error Recovery. The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer. The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.6 NoResponseTimer The NoResponseTimer is used by the Policy Engine in a Source to determine that its Port Partner is not responding after a Hard Reset. When the NoResponseTimer times out, the Policy Engine Shall issue up to nHardResetCount additional Hard Resets before determining that the Port Partner is non-responsive to USB Power Delivery messaging. If the Source fails to receive a GoodCRC Message in response to a Source_Capabilities Message within tNoResponse of:  The last bit of a Hard Reset Signaling being sent by the PHY Layer if the Hard Reset Signaling was initi- ated by the Sink.  The last bit of a Hard Reset Signaling being received by the PHY Layer if the Hard Reset Signaling was initiated by the Source. Then the Source Shall issue additional Hard Resets up to nHardResetCount times (see Section 6.8.3, "Hard Reset"). For a non-responsive device, the Policy Engine in a Source May either decide to continue sending Source_Capabilities Messages or to go to non-USB Power Delivery operation and cease sending Source_Capabilities Messages. 6.6.7 BIST Timers 6.6.7.1 tBISTCarrierMode tBISTCarrierMode is used to define the maximum time that a UUT has to enter BIST Carrier Mode when requested by a Tester. Page 254 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A UUT Shall enter BIST Carrier Mode within tBISTCarrierMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. In BIST Carrier Mode when transmitting a continuous carrier signal transmission Shall start as soon as the UUT enters BIST Mode. 6.6.7.2 BISTContModeTimer The BISTContModeTimer is used by a UUT to ensure that a Continuous BIST Mode (i.e., BIST Carrier Mode) is exited in a timely fashion. A UUT that has been put into a Continuous BIST Mode Shall return to normal operation (either PE_SRC_Transition_to_default, PE_SNK_Transition_to_default, or PE_CBL_Ready) within tBISTContMode of starting to transmit a continuous carrier signal. 6.6.7.3 tBISTSharedTestMode tBISTSharedTestMode is used to define the maximum time that a UUT has to enter BIST Shared Capacity Test Mode when requested by a Tester. A UUT Shall enter BIST Shared Capacity Test Mode and send a new Source_Capabilities Message from all Ports within the Shared Capacity Group within tBISTSharedTestMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. 6.6.8 Power Role Swap Timers 6.6.8.1 SwapSourceStartTimer The SwapSourceStartTimer Shall be used by the New Source, after a Power Role Swap or Fast Role Swap, to ensure that it does not send Source_Capabilities Message before the New Sink is ready to receive the Source_Capabilities Message. The New Source Shall Not send the Source_Capabilities Message earlier than tSwapSourceStart after the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. The Sink Shall be ready to receive a Source_Capabilities Message tSwapSinkReady after having sent the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. 6.6.9 Soft Reset Timers 6.6.9.1 tSoftReset A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure. This Shall cause the Source or Sink to send a Soft_Reset Message, transmission of which Shall be completed within tSoftReset of the CRCReceiveTimer expiring. 6.6.9.2 tProtErrSoftReset If the Protocol Error occurs that causes the Source or Sink to send a Soft_Reset Message, the transmission of the Soft_Reset Message Shall be completed within tProtErrSoftReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.10 Data Reset Timers 6.6.10.1 VCONNDischargeTimer The VCONNDischargeTimer is used by the Policy Engine in the DFP to ensure the UFP actively discharges VCONN in a timely manner to ensure the cable will restore Ra. Once the UFP has discharged VCONN below vRaReconnect (see [USB Type-C 2.4]) it sends a PS_RDY Message (see also Section 7.1.15, "VCONN Power Cycle"). If the DFP does not receive a PS_RDY Message from the UFP within tVCONNSourceDischarge of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message, the VCONNDischargeTimer will time out and the Policy Engine Shall enter the ErrorRecovery State. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 255 6.6.10.2 tDataReset The DFP Shall complete the Data_Reset process (as defined in Section 6.3.14, "Data_Reset Message") within tDataReset of the last bit of the GoodCRC Message EOP, corresponding to the Accept Message, being transmitted by the PHY Layer. 6.6.10.3 DataResetFailTimer The DataResetFailTimer Shall be used by the DFP's Policy Engine to ensure the Data Reset process completes within tDataResetFail of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the DFP's DataResetFailTimer expires, the DFP Shall enter the ErrorRecovery State. 6.6.10.4 DataResetFailUFPTimer The DataResetFailUFPTimer Shall be used by the UFP's Policy Engine to ensure the Data Reset process completes within tDataResetFailUFP of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the UFP's DataResetFailUFPTimer expires, the UFP Shall enter the ErrorRecovery State. 6.6.11 Hard Reset Timers 6.6.11.1 HardResetCompleteTimer The HardResetCompleteTimer is used by the Protocol Layer in the case where it has asked the PHY Layer to send Hard Reset Signaling and the PHY Layer is unable to send the Signaling within a reasonable time due to a non-Idle channel. If the PHY Layer does not indicate that the Hard Reset Signaling has been sent within tHardResetComplete of the Protocol Layer requesting transmission, then the Protocol Layer Shall inform the Policy Engine that the Hard Reset Signaling has been sent in order to ensure the power supply is reset in a timely fashion. 6.6.11.2 PSHardResetTimer The PSHardResetTimer is used by the Policy Engine in a Source to ensure that the Sink has had sufficient time to process Hard Reset Signaling before turning off its power supply to VBUS. When a Hard Reset occurs the Source, stops driving VCONN, removes Rp from the CC pin and starts to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. See Section 7.1.5, "Response to Hard Resets". 6.6.11.3 tDRSwapHardReset If a DR_Swap Message is received during Modal Operation then a Hard Reset Shall be initiated by the recipient of the unexpected DR_Swap Message; Hard Reset Signaling Shall be generated within tDRSwapHardReset of the EOP of the GoodCRC sent in response to the DR_Swap Message. 6.6.11.4 tProtErrHardReset If a Protocol Error occurs that directly leads to a Hard Reset, the transmission of the Hard Reset Signaling Shall be completed within tProtErrHardReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.12 Structured VDM Timers 6.6.12.1 VDMResponseTimer The VDMResponseTimer Shall be used by the Initiator's Policy Engine to ensure that a Structured VDM Command request needing a response (e.g. Discover Identity Command request) is responded to within a bounded time of tVDMSenderResponse. The VDMResponseTimer Shall be applied to all Structured VDM Commands except the Page 256 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Enter Mode and Exit Mode Commands which have their own timers (VDMModeEntryTimer and VDMModeExitTimer respectively). Failure to receive the expected response is detected when the VDMResponseTimer expires. The Policy Engine's response when the VDMResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The VDMResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected VDM Command response, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMReceiverResponse in order to ensure that the sender's VDMResponseTimer does not expire. The tVDMReceiverResponse time Shall be measured from the time the last bit of the Message EOP has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.2 VDMModeEntryTimer The VDMModeEntryTimer Shall be used by the Initiator's Policy Engine to ensure that the response to a Structured VDM Enter Mode Command request (ACK or NAK with ACK indicating that the requested Alternate Mode has been entered) arrives within a bounded time of tVDMWaitModeEntry. Failure to receive the expected response is detected when the VDMModeEntryTimer expires. The Policy Engine's response when the VDMModeEntryTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.1, "DFP Structured VDM Mode Entry State Diagram"). The VDMModeEntryTimer Shall be started from the time the last bit of the EOP of the GoodCRC Message, corresponding to the VDM Command request, has been received by the PHY Layer. The VDMModeEntryTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected Structured VDM Command response (ACK, NAK or BUSY), has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMEnterMode in order to ensure that the sender's VDMModeEntryTimer does not expire. The tVDMEnterMode time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to VDM Command Request, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.3 VDMModeExitTimer The VDMModeExitTimer Shall be used by the Initiator's Policy Engine to ensure that the ACK response to a Structured VDM Exit Mode Command, indicating that the requested Alternate Mode has been exited, arrives within a bounded time of tVDMWaitModeExit. Failure to receive the expected response is detected when the VDMModeExitTimer expires. The Policy Engine's response when the VDMModeExitTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.2, "DFP Structured VDM Mode Exit State Diagram"). The VDMModeExitTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMModeExitTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the expected Structured VDM Command response ACK, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMExitMode in order to ensure that the sender's VDMModeExitTimer does not expire. The tVDMExitMode time Shall be measured from the time the last bit of the Message EOP has been received by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 257 6.6.12.4 tVDMBusy The Initiator Shall wait at least tVDMBusy, after receiving a BUSY Command response, before repeating the Structured VDM request again. 6.6.13 VCONN Timers 6.6.13.1 VCONNOnTimer The VCONNOnTimer is used during a VCONN Swap. The VCONNOnTimer Shall be started when:  The last bit of GoodCRC Message EOP, corresponding to the Accept Message, is transmitted or received by the PHY Layer. The VCONNOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, is transmitted by the PHY Layer. Prior to sending the PS_RDY Message, the Port Shall have turned VCONN On. 6.6.13.2 tVCONNSourceOff The tVCONNSourceOff time applies during a VCONN Swap. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, being transmitted by the PHY Layer. 6.6.14 tCableMessage Ports compliant with Revision 3.x of the specification Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet even when communicating using [USBPD 2.0] with a Cable Plug. This specification defines Collision Avoidance mechanisms that obviate the need for this time. Cable Plugs Shall only wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet when operating at [USBPD 2.0]. When operating at Revisions higher than [USBPD 2.0] Cable Plugs Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet. 6.6.15 DiscoverIdentityTimer The DiscoverIdentityTimer is used prior to or during an Explicit Contract when discovering whether a Cable Plug is PD Capable using SOP’. When performing Cable Discovery during an Explicit Contract the Discover Identity Command request Shall be sent every tDiscoverIdentity. No more than nDiscoverIdentityCount Discover Identity Messages without a GoodCRC Message response Shall be sent. If no GoodCRC Message response is received after nDiscoverIdentityCount Discover Identity Command requests have been sent by a Port, the Port Shall Not send any further SOP’/SOP’’ Messages. 6.6.16 Collision Avoidance Timers 6.6.16.1 SinkTxTimer The SinkTxTimer is used by the Protocol Layer in a Source to allow the Sink to complete its transmission before initiating an AMS. The Source Shall wait a minimum of tSinkTx after changing Rp from SinkTxOK to SinkTxNG before initiating an AMS by sending a Message. A Sink Shall only initiate an AMS when it has determined that Rp is set to SinkTxOK. Page 258 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.16.2 tSrcHoldsBus If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. 6.6.17 Fast Role Swap Timers 6.6.17.1 tFRSwap5V The tFRSwap5V time Shall be measured from:  The later of:  The last bit of the GoodCRC Message EOP, corresponding to the Accept Message or  VBUS being within vSafe5V.  Until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. During a Fast Role Swap, the Initial Source Shall start the PS_RDY Message within tFRSwap5V after both:  The Initial Source has sent the Accept Message, and  VBUS is at or below vSafe5V. 6.6.17.2 tFRSwapComplete During a fast-role swap, the Initial Sink Shall respond with a the PS_RDY Message within tFRSwapComplete after it has received the PS_RDY Message from the Initial Source. The tFRSwapComplete time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. 6.6.17.3 tFRSwapInit That last bit of the EOP of the FR_Swap Message Shall be transmitted by the New Source no later than tFRSwapInit after the Fast Role Swap Request has been detected (see Section 5.8.6.3, "Fast Role Swap Detection"). 6.6.18 Chunking Timers 6.6.18.1 ChunkingNotSupportedTimer The ChunkingNotSupportedTimer is used by a Source or Sink which does not support multi-chunk Chunking but has received a Message Chunk. The ChunkingNotSupportedTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to a Message Chunk of a multi-chunk Message, is transmitted by the PHY Layer. The Policy Engine Shall Not send its Not_Supported Message before the ChunkingNotSupportedTimer expires. 6.6.18.2 ChunkSenderRequestTimer The ChunkSenderRequestTimer is used during a Chunked Message transmission. The ChunkSenderRequestTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Response is responded to within a bounded time of tChunkSenderRequest. Failure to receive the expected response is detected when the ChunkSenderRequestTimer expires. The ChunkSenderRequestTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is received by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 259 The ChunkSenderRequestTimer Shall be stopped when:  The last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, is trans- mitted by the PHY Layer.  A Message other than a Chunk Request is received from the Protocol Layer Rx. The receiver of a Chunk Response requiring a Chunk Request Shall respond with a Chunk Request within tChunkReceiverRequest in order to ensure that the sender's ChunkSenderRequestTimer does not expire. The tChunkReceiverRequest time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Response Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.18.3 ChunkSenderResponseTimer The ChunkSenderResponseTimer is used during a Chunked Message transmission. The ChunkSenderResponseTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Request is responded to within a bounded time of tChunkSenderResponse. Failure to receive the expected response is detected when the ChunkSenderResponseTimer expires. The ChunkSenderResponseTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Request Message, is received by the PHY Layer. The ChunkSenderResponseTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is transmitted by the PHY Layer.  A Message other than a Chunk is received from the Protocol Layer. The receiver of a Chunk Request requiring a Chunk Response Shall respond with a Chunk Response within tChunkReceiverResponse in order to ensure that the sender's ChunkSenderResponseTimer does not expire. The tChunkReceiverResponse time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.19 Programmable Power Supply Timers 6.6.19.1 SinkPPSPeriodicTimer The SinkPPSPeriodicTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSRequest when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is sent periodically as a keep alive mechanism. SinkPPSPeriodicTimer Shall be re-initialized and restarted on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any received Message, that causes the Sink to enter the PE_SNK_Ready state. The Sink Shall stop the SinkPPSPeriodicTimer on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any Message, or the last bit of any Signaling is received, by the PHY Layer, from the Source and by the Sink that causes the Sink to leave the PE_SNK_Ready state. 6.6.19.2 SourcePPSCommTimer The SourcePPSCommTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSTimeout when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is received periodically as a keep alive mechanism. Page 260 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SourcePPSCommTimer Shall be re-initialized and restarted when, after receiving any Message that causes the Source to enter the PE_SRC_Ready state, the last bit of the corresponding GoodCRC Message EOP is transmitted by the PHY Layer. The Source Shall stop the SourcePPSCommTimer when:  After receiving any Message that causes the Source to leave the PE_SRC_Ready state, the last bit of the of the corresponding GoodCRC Message EOP is sent by the PHY Layer, or  The last bit of any Signaling is received by the PHY Layer from the Sink by the Source that causes the Source to leave the PE_SRC_Ready state. When the SourcePPSCommTimer times out the Source Shall issue Hard Reset Signaling. 6.6.20 tEnterUSB The DFP Shall send the Enter_USB Message within tEnterUSB of either:  The last bit of the GoodCRC acknowledging the Data_Reset_Complete Message in response to the Data_Reset Message or  A PD Connection, specifically the last bit of the GoodCRC acknowledging the Source_Capabilities Mes- sage after the initial entry into the PE_SRC_Send_Capabilities state or  The last bit of the GoodCRC acknowledging the Accept Message in response to the DR_Swap Message Failure by the DFP to meet this timeout parameter can result in the ports not transitioning into [USB4] operation. Any AMS initiated by the UFP prior to receiving the Enter_USB Message will delay reception of the Enter_USB Message and [USB4] operation, therefore a USB4® -capable UFP Should Not initiate any AMS until the DFP has been given time to send the Enter_USB Message. 6.6.21 EPR Timers 6.6.21.1 SinkEPREnterTimer Timer The SinkEPREnterTimer is used to ensure the EPR Mode entry process completes within tEnterEPR. The Sink Shall start the timer when it sees the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 1 (Enter). The Sink Shall stop the timer when the last bit of the corresponding GoodCRC Message EOP, corresponding to the received EPR_Mode Message with the Action field set to 3 (Enter Succeeded), has been transmitted by the PHY Layer. If the timer expires the Sink Shall send a Soft_Reset Message. 6.6.21.2 SinkEPRKeepAlive Timer The SinkEPRKeepAliveTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSinkEPRKeepAlive. The Sink Shall initialize and run this timer upon entry into the PE_SNK_Ready State when in EPR Mode and Shall stop it upon exit from the PE_SNK_Ready when in EPR Mode. While operating in EPR Mode, the Sink Shall stop the SinkEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Source, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Sink Shall send an EPR_KeepAlive Message. 6.6.21.3 SourceEPRKeepAlive Timer The SourceEPRKeepAliveTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSourceEPRKeepAlive. The Source Shall initialize Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 261 and run this timer upon entry into the PE_SRC_Ready State when in EPR Mode and Shall disable it upon exit from the PE_SRC_Ready State when EPR Mode. While operating in EPR Mode, the Source Shall stop the SourceEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Sink, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Source Shall send Hard Reset Signaling. 6.6.21.4 tEPRSourceCableDiscovery After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap an EPR Source Shall discover the Cable Plug within tEPRSourceCableDiscovery of entering the First Explicit Contract. The EPR Source Shall send the Discover Identity REQ Command, to the Cable Plug, within tEPRSourceCableDiscovery of receiving the GoodCRC Message acknowledging the PS_RDY Message as part of the Explicit Contract Negotiation. Note: If the EPR Source is not the VCONN Source, tEPRSourceCableDiscovery, will also include the time needed for the VCONN Swap. Page 262 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.22 Time Values and Timers Table 6.68, "Time Values" summarizes the values for the timers listed in this section. For each Timer Value, a given implementation Shall pick a fixed value within the range specified. Table 6.69, "Timers" lists the timers. Table 6.68 Time Values Parameter Value (min) Value (Nom) Value (max) Units Reference tACTempUpdate 500 ms Section 6.5.2.2.1 tBISTContMode 30 45 60 ms Section 6.6.7.2 tBISTCarrierMode 300 ms Section 6.6.7.1 tBISTSharedTestMode 1 s Section 6.6.7.3 tCableMessage 750 µs Section 6.6.14 tCapabilitiesMismatchResponse 2 s Section 6.4.2.3 tChunkingNotSupported 40 45 50 ms Section 6.6.18.1 tChunkReceiverRequest 15 ms Section 6.6.18.2 tChunkReceiverResponse 15 ms Section 6.6.18.3 tChunkSenderRequest 24 27 30 ms Section 6.6.18.2 tChunkSenderResponse 24 27 30 ms Section 6.6.18.3 tDataReset 200 225 250 ms Section 6.6.10.2 tDataResetFail 300 400 ms Section 6.6.10.3 tDataResetFailUFP 450 550 ms Section 6.6.10.4 tDiscoverIdentity 40 50 ms Section 6.6.14 tDRSwapHardReset 15 ms Section 6.6.11.3 tDRSwapWait 100 ms Section 6.6.4.3 tEnterUSB 500 ms Section 6.6.20 tEnterUSBWait 100 ms Section 6.6.4.7 tEnterEPR 450 500 550 ms Section 6.6.21.1 tEPRSourceCableDiscovery 2 s Section 6.6.21.4 tFirstSourceCap 250 ms Section 6.6.3.3 tFRSwap5V 15 ms Section 6.6.17.1 tFRSwapComplete 15 ms Section 6.6.17.2 tFRSwapInit 15 ms Section 6.6.17.3 tHardReset 5 ms Section 6.3.13 tHardResetComplete 4 4.5 5 ms Section 6.6.9 tSourceEPRKeepAlive 0.750 0.875 1.000 s Section 6.6.21.3 tSinkEPRKeepAlive 0.250 0.375 0.500 s Section 6.6.21.2 tNoResponse 4.5 5.0 5.5 s Section 6.6.6 tPPSRequest 10 s Section 6.6.19.1 tPPSTimeout 12.0 13.5 15.0 s Section 6.6.19.2 tProtErrHardReset 15 ms Section 6.6.11.4 tProtErrSoftReset 15 ms Section 6.6.9.2 tPRSwapWait 100 ms Section 6.6.4.2 tPSHardReset 25 30 35 ms Section 6.6.11.2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 263 tPSSourceOff SPR Mode 750 835 920 ms Section 6.6.5.2 EPR Mode 1120 1260 1400 tPSSourceOn SPR Mode 390 435 480 ms Section 6.6.5.3 tPSTransition SPR Mode 450 500 550 ms Section 6.6.5.1 EPR Mode 830 925 1020 tReceive 0.9 1.0 1.1 ms Section 6.6.1 tReceiverResponse 15 ms Section 6.6.2 tRetry 195 µs Section 6.6.1 tSenderResponse 27 30 33 ms Section 6.6.2 tSinkDelay 5 ms Section 5.7 tSinkRequest 100 ms Section 6.6.4.1 tSinkTx 16 18 20 ms Section 6.6.16 tSoftReset 15 ms Section 6.8.1 tSrcHoldsBus 50 ms Section 8.3.3.2 tSwapSinkReady 15 ms Section 6.6.8.1 tSwapSourceStart 20 ms Section 6.6.8.1 tTransmit 195 µs Section 6.6.1 tTypeCSendSourceCap 100 150 200 ms Section 6.6.3.1 tTypeCSinkWaitCap 310 465 620 ms Section 6.6.3.2 tVCONNSourceDischarge 160 200 240 ms Section 6.6.10.1 tVCONNSourceOff 25 ms Section 6.6.13 tVcONNSourceOn 50 ms Section 6.3.11 tVCONNSourceTimeout 100 150 200 ms Section 6.6.13 tVCONNSwapWait 100 ms Section 6.6.4.4 tVCONNSwapDelayDFP 100 ms Section 6.6.4.5 tVCONNSwapDelayUFP 500 ms Section 6.6.4.6 tVDMBusy 50 ms Section 6.6.12.4 tVDMEnterMode 25 ms Section 6.6.12.2 tVDMExitMode 25 ms Section 6.6.12.3 tVDMReceiverResponse 15 ms Section 6.6.12.1 tVDMSenderResponse 24 27 30 ms Section 6.6.12.1 tVDMWaitModeEntry 40 45 50 ms Section 6.6.12.2 tVDMWaitModeExit 40 45 50 ms Section 6.6.12.3 Table 6.68 Time Values (Continued) Parameter Value (min) Value (Nom) Value (max) Units Reference Page 264 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.69 Timers Timer Parameter Used By Reference BISTContModeTimer tBISTContMode Policy Engine Section 6.6.7.2 ChunkingNotSupportedTimer tChunkingNotSupported Policy Engine Section 6.6.18.1 ChunkSenderRequestTimer tChunkSenderRequest Protocol Layer Section 6.6.18.2 ChunkSenderResponseTimer tChunkSenderResponse Protocol Layer Section 6.6.18.3 CRCReceiveTimer tReceive Protocol Layer Section 6.6.1 DataResetFailTimer tDataResetFail Policy Engine Section 6.6.10.3 DataResetFailUFPTimer tDataResetFailUFP Policy Engine Section 6.6.10.4 DiscoverIdentityTimer tDiscoverIdentity Policy Engine Section 6.6.15 HardResetCompleteTimer tHardResetComplete Protocol Layer Section 6.6.9 NoResponseTimer tNoResponse Policy Engine Section 6.6.6 PSHardResetTimer tPSHardReset Policy Engine Section 6.6.11.2 PSSourceOffTimer tPSSourceOff Policy Engine Section 6.6.5.2 PSSourceOnTimer tPSSourceOn Policy Engine Section 6.6.5.3 PSTransitionTimer tPSTransition Policy Engine Section 6.6.5.1 SenderResponseTimer tSenderResponse Policy Engine Section 6.6.2 SinkEPREnterTimer tEnterEPR Policy Engine Section 6.6.21.1 SinkEPRKeepAliveTimer tSinkEPRKeepAlive Policy Engine Section 6.6.21.2 SinkPPSPeriodicTimer tPPSRequest Policy Engine Section 6.6.19.1 SinkRequestTimer tSinkRequest Policy Engine Section 6.6.4 SinkWaitCapTimer tTypeCSinkWaitCap Policy Engine Section 6.6.3.2 SourceCapabilityTimer tTypeCSendSourceCap Policy Engine Section 6.6.3.1 SourceEPRKeepAliveTimer tSourceEPRKeepAlive Policy Engine Section 6.6.21.3 SourcePPSCommTimer tPPSTimeout Policy Engine Section 6.6.19.2 SinkTxTimer tSinkTx Protocol Layer Section 6.6.16 SwapSourceStartTimer tSwapSourceStart Policy Engine Section 6.6.8.1 VCONNDischargeTimer tVCONNSourceDischarge Policy Engine Section 6.6.10.1 VCONNOnTimer tVCONNSourceTimeout Policy Engine Section 6.6.13.1 VDMModeEntryTimer tVDMWaitModeEntry Policy Engine Section 6.6.12.2 VDMModeExitTimer tVDMWaitModeExit Policy Engine Section 6.6.12.3 VDMResponseTimer tVDMSenderResponse Policy Engine Section 6.6.12.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 265 6.7 Counters 6.7.1 MessageID Counter The MessageIDCounter is a rolling counter, ranging from 0 to nMessageIDCount, used to detect duplicate Messages. This value is used for the MessageID field in the Message Header of each transmitted Message. Each Port Shall maintain a copy of the last MessageID value received from its Port Partner. Devices that support multiple ports, such as Hubs, Shall maintain copies of the last MessageID on a per Port basis. A Port which communicates using SOP* Packets Shall maintain copies of the last MessageID for each type of SOP* it uses. The transmitter Shall use the MessageID in a GoodCRC Message to verify that a particular Message was received correctly. The receiver Shall use the MessageID to detect duplicate Messages. 6.7.1.1 Transmitter Usage The Transmitter Shall use the MessageID as follows:  Upon receiving either Hard Reset Signaling, or a Soft_Reset Message, the transmitter Shall set its MessageIDCounter to zero and re-initialize its retry mechanism.  If a GoodCRC Message with a MessageID matching the MessageIDCounter is not received before the CRCReceiveTimer expires, it Shall retry the same Packet up to nRetryCount times using the same MessageID.  If a GoodCRC Message is received with a MessageID matching the current MessageIDCounter before the CRCReceiveTimer expires, the transmitter Shall re-initialize its retry mechanism and increment its MessageIDCounter.  If the Message is aborted by the Policy Engine, the transmitter Shall delete the Message from its transmit buffer, re-initialize its retry mechanism and increment its MessageIDCounter. 6.7.1.2 Receiver Usage The Receiver Shall use the MessageID as follows:  When the first good Packet is received after a reset, the receiver Shall store a copy of the received MessageID value.  For subsequent Messages, if MessageID value in a received Message is the same as the stored value, the receiver Shall return a GoodCRC Message with that MessageID value and drop the Message (this is a retry of an already received Message). Note: This Shall Not apply to the Soft_Reset Message which always has a MessageID value of zero.  If MessageID value in the received Message is different than the stored value, the receiver Shall return a GoodCRC Message with the new MessageID value, store a copy of the new MessageID value and pro- cess the Message. 6.7.2 Retry Counter The RetryCounter is used by a Port whenever there is a Message transmission failure (timeout of CRCReceiveTimer). If the nRetryCount retry fails, then the link Shall be reset using the Soft Reset mechanism. The following rules apply to retries when there is a Message transmission failure (see also Section 6.12.2.2, "Protocol Layer Message Transmission"):  Cable Plugs Shall Not retry Messages.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are not Chunked (Chunked flag set to zero) Shall Not be retried. Page 266 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Extended Messages of Data Size ≤ MaxExtendedMsgLegacyLen (Chunked flag set to zero or one) Shall be retried.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are Chunked (Chunked flag set to one) individual Chunks Shall be retried. When Messages are not retried, then the RetryCounter is not used. Higher layer protocols are expected to accommodate Message delivery failure or failure to receive a GoodCRC Message. 6.7.3 Hard Reset Counter The HardResetCounter is used to retry the Hard Reset whenever there is no response from the remote device (see Section 6.6.6, "NoResponseTimer"). Once the Hard Reset has been retried nHardResetCount times then it Shall be assumed that the remote device is non-responsive. 6.7.4 Capabilities Counter The CapsCounter is used to count the number of Source_Capabilities Messages which have been sent by a Source at power up or after a Hard Reset. Implementation of the CapsCounter is Optional but May be used by any Source which wishes to preserve power by not sending Source_Capabilities Messages after a period of time. When the CapsCounter is implemented and the Source detects that a Sink is Attached then after nCapsCount Source_Capabilities Messages have been sent the Source Shall decide that the Sink is non-responsive, stop sending Source_Capabilities Messages and disable PD. A Sink Shall use the SinkWaitCapTimer to trigger the resending of Source_Capabilities Messages by a USB Power Delivery capable Source which has previously stopped sending Source_Capabilities Messages. Any Sink which is Attached and does not detect a Source_Capabilities Message, Shall issue Hard Reset Signaling when the SinkWaitCapTimer times out in order to reset the Source. Resetting the Source Shall also reset the CapsCounter and restart the sending of Source_Capabilities Messages. 6.7.5 Discover Identity Counter When sending Discover Identity Messages to a Cable Plug a Port Shall maintain a count of Messages sent (DiscoverIdentityCounter). No more than nDiscoverIdentityCount Discover Identity Messages Shall be sent by the Port without receiving a GoodCRC Message response. A VCONN Swap Shall reset the DiscoverIdentityCounter. 6.7.6 VDMBusyCounter When sending Responder BUSY responses to a Structured Vendor_Defined Message a UFP or Cable Plug Shall maintain a count of Messages sent (VDMBusyCounter). No more than nBusyCount Responder BUSY responses Shall be sent. The VDMBusyCounter Shall be reset on sending a non-BUSY response. Products wishing to meet [USB Type-C 2.4] requirements for Alternate Mode entry Should use an nBusyCount of 1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 267 6.7.7 Counter Values and Counters Table 6.70, "Counter Parameters" lists the counters used in this section and Table 6.71, "Counters" shows the corresponding parameters. Table 6.70 Counter Parameters Parameter Value Reference nBusyCount 5 Section 6.7.6 nCapsCount 50 Section 6.7.4 nDiscoverIdentityCount 20 Section 6.7.5 nHardResetCount 2 Section 6.7.3 nMessageIDCount 7 Section 6.7.1 nRetryCount 2 Section 6.7.2 Table 6.71 Counters Counter Max Reference CapsCounter nCapsCount Section 6.7.4 DiscoverIdentityCounter nDiscoverIdentityCount Section 6.7.5 HardResetCounter nHardResetCount Section 6.7.3 MessageIDCounter nMessageIDCount Section 6.7.1 RetryCounter nRetryCount Section 6.7.2 VDMBusyCounter nBusyCount Section 6.7.6 Page 268 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.8 Reset Resets are a necessary response to protocol or other error conditions. USB Power Delivery defines four different types of reset:  Soft Reset, which resets protocol.  Data Reset which resets the USB Communications.  Hard Reset which resets both the power supplies and protocol  Cable Reset which resets the cable. 6.8.1 Soft Reset and Protocol Error A Soft_Reset Message is used to cause a Soft Reset of protocol communication when this has broken down in some way. It Shall Not have any impact on power supply operation but is used to correct a Protocol Error occurring during an Atomic Message Sequence (AMS). The Soft Reset May be triggered by either Port Partner in response to the Protocol Error. Protocol Errors are any unexpected Message during an AMS. If the first Message in an AMS has been passed to the Protocol Layer by the Policy Engine but has not yet been sent (i.e., a GoodCRC Message acknowledging the Message has not been received) when the Protocol Error occurs, the Policy Engine Shall Not issue a Soft Reset but Shall return to the PE_SNK_Ready or PE_SRC_Ready state and then process the incoming Message. If the incoming Message is an Unexpected Message received in the PE_SNK_Ready or PE_SRC_Ready state, the Policy Engine Shall issue a Soft Reset. If the Protocol Error occurs during an AMS this Shall lead to a Soft Reset in order to re-synchronize the Policy Engine state machines (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams") except when the voltage is transition when a Protocol Error Shall lead to a Hard Reset (see Section 6.6.11.4, "tProtErrHardReset" and Section 8.3.3.2, "Policy Engine Source Port State Diagram"). Details of AMS's can be found in Section 8.3.2.1.3, "Atomic Message Sequences". An Unrecognized Message or Unsupported Message received in the PE_SNK_Ready or PE_SRC_Ready states, Shall Not cause a Soft_Reset Message to be generated but instead a Not_Supported Message Shall be generated. A Soft_Reset Message Shall be sent regardless of the Rp value either SinkTxOK or SinkTxNG if it is the correct response in that state. Note: This means that a Soft_Reset Message can be sent during an AMS regardless of the Rp value either SinkTxOK or SinkTxNG when responding to a Protocol Error. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 269 Table 6.72, "Response to an incoming Message (except VDM)" and Table 6.73, "Response to an incoming VDM" summarize the responses that Shall be made to an incoming Message including VDMs. A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure resulting in a Soft Reset (see Section 6.6.9.1, "tSoftReset"). A Soft Reset Shall impact the USB Power Delivery layers in the following ways:  PHY Layer: Reset not required since the PHY Layer resets on each Packet transmission/reception.  Protocol Layer: Reset MessageIDCounter, RetryCounter and state machines. Table 6.72 Response to an incoming Message (except VDM) Recipient’s Power Role Recipient’s state Incoming Message Recognized Unrecognized Supported Unsupported Expected Unexpected Source PE_SRC_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (power not transitioning1) Process Message Soft_Reset Message2 During AMS (power transitioning1) Process Message Hard Reset Signaling Sink PE_SNK_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (not power transitioned) Process Message Soft_Reset Message2 During AMS (power transitioned) Process Message Hard Reset Signaling 1) “Power transitioning” means the Policy Engine is in PE_SRC_Transition_Supply State or PE_SNK_Transition_Sink State or PE_FRS_SNK_SRC_Start_AMS State. 2) The Soft_Reset Message Shall be sent using the SOP* of the incoming Message. 3) The Not_Supported Message Shall be sent using the SOP* of the incoming Message. Table 6.73 Response to an incoming VDM Recipient's Role Unstructured VDM Structured VDM Supported Unsupported Unrecognized Supported Unsupported Unrecognized DFP or UFP Defined by vendor Not_Supported Message Not_Supported Message See Section 6.13.5 Not_Supported Message NAK Command Cable Plug Defined by vendor Message Ignored Message Ignored See Section 6.13.5 Message Ignored NAK Command Page 270 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Policy Engine: Reset state dependent behavior by performing an Explicit Contract Negotiation.  Power supply: Shall Not change. Note: When in SPR Mode the Source sends a Source_Capabilities Message and when in EPR Mode the Source sends an EPR_Source_Capabilities Message. A Soft Reset is performed using an AMS (see Table 8.8, "AMS: Soft Reset"). Message numbers Shall be set to zero prior to sending the Soft_Reset/Accept Message since the issue might be with the counters. The sender of a Soft_Reset Message Shall reset its MessageIDCounter and RetryCounter, the receiver of the Message Shall reset its MessageIDCounter and RetryCounter before sending the Accept Message response. Any failure in the Soft Reset process will trigger a Hard Reset when SOP Packets are being used or Cable Reset, sent by the DFP only, for any other SOP* Packets; for example a GoodCRC Message is not received during the Soft Reset process (see Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). 6.8.2 Data Reset A Data_Reset Message is used by a Port to reset its USB data connection and to exit all Alternate Modes both with its Port Partner and in the Cable Plug(s).  The Data Reset process May be initiated by either Port Partner sending a Data_Reset Message. A Data Reset impacts USB Power Delivery in the following ways:  Shall Not change the Port Power Roles (Source/Sink) or Port Data Roles (DFP/UFP).  Shall Not change the existing Explicit Contract.  Shall cause all Active Modes to be exited.  Shall reset the cable by Power cycling VCONN.  The DFP Shall become the VCONN Source.  If the Data Reset process fails, then the Port Shall enter the ErrorRecovery State as defined in [USB Type-C 2.4]. See Section 6.3.14, "Data_Reset Message" for details of Data Reset operation. 6.8.3 Hard Reset Hard Resets are signaled by an ordered set as defined in Section 5.6.4, "Hard Reset". Both the sender and recipient Shall cause their power supplies to return to their default states (see Section 7.3.3.1, "Source Initiated Hard Reset" and Section 7.3.3.2, "Sink Initiated Hard Reset" for details of voltage transitions). In addition, their respective Protocol Layers Shall be reset as for the Soft Reset. This allows the Attached devices to be in a state where they can re-establish USB PD communication. Hard Reset is retried up to nHardResetCount times (see also Section 6.6.6, "NoResponseTimer" and Section 6.7.3, "Hard Reset Counter"). Note: Even though VBUS drops to vSafe0V during a Hard Reset a Sink will not see this as a disconnect since this is expected behavior. A Hard Reset Shall Not cause any change to either the Rp/Rd resistor being asserted. If there has been a Data Role Swap the Hard Reset Shall cause the Port Data Role to be changed back to DFP for a Port with the Rp resistor asserted and UFP for a Port with the Rd resistor asserted. When VCONN is supported (see [USB Type-C 2.4]) the Hard Reset Shall cause the Port with the Rp resistor asserted to supply VCONN and the Port with the Rd resistor asserted to turn off VCONN. In effect the Hard Reset will revert the Ports to their default state based on their CC line resistors. Removing and reapplying VCONN from the Cable Plugs also ensures that they re-establish their configuration as either SOP’ or SOP’’ based on the location of VCONN (see [USB Type-C 2.4]). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 271 If the Hard Reset is insufficient to clear the error condition, then the Port Shall use USB Type-C ErrorRecovery as defined in [USB Type-C 2.4]. A Sink Shall be able to send Hard Reset Signaling regardless of the value of Rp (see Section 5.7, "Collision Avoidance"). 6.8.3.1 Cable Plugs and Hard Reset Cable Plugs Shall Not generate Hard Reset Signaling but Shall monitor for Hard Reset Signaling between the Port Partners and Shall reset when this is detected (see Section 8.3.3.25.2.2, "Cable Plug Hard Reset State Diagram"). The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. 6.8.3.2 Modal Operation and Hard Reset A Hard Reset Shall cause EPR Mode and all Active Modes to be exited by both Port Partners and any Cable Plugs (see Section 6.4.4.3.4, "Enter Mode Command"). 6.8.4 Cable Reset Cable Resets are signaled by an ordered set as defined in Section 5.6.5, "Cable Reset". Both the sender and recipient of Cable Reset Signaling Shall reset their respective Protocol Layers. The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. The DFP must be supplying VCONN prior to a Cable Reset. If VCONN has been turned off the DFP Shall turn on VCONN prior to generating Cable Reset Signaling. If there has been a VCONN Swap and the UFP is currently supplying VCONN, the DFP Shall perform a VCONN Swap such that it is supplying VCONN prior to generating Cable Reset Signaling. Only a DFP Shall generate Cable Reset Signaling. A DFP Shall only generate Cable Reset Signaling within an Explicit Contract. A Cable Reset Shall cause all Active Modes in the Cable Plugs to be exited (see Section 6.4.4.3.4, "Enter Mode Command"). Page 272 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.9 Accept, Reject and Wait The recipient of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message Shall respond by sending one of the following responses:  An Accept Message in response to a Valid request which can be serviced immediately (see Section 6.3.3, "Accept Message").  A Wait Message in response to a Valid request which cannot be serviced immediately but could be ser- viced at a later time (see Section 6.3.12, "Wait Message").  A Reject Message in response to an Invalid request or a request which is outside of the device's design Capabilities (see Section 6.3.4, "Reject Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 273 6.10 Collision Avoidance To avoid Message collisions due to asynchronous Messaging sent from the Sink, the Source sets Rp to SinkTxOK to indicate to the Sink that it is OK to initiate an AMS. When the Source wishes to initiate an AMS, it sets Rp to SinkTxNG. When the Sink detects that Rp is set to SinkTxOK it May initiate an AMS. When the Sink detects that Rp is set to SinkTxNG it Shall Not initiate an AMS and Shall only send Messages that are part of an AMS the Source has initiated. Note: This restriction applies to SOP* AMS's i.e., for both Port to Port and Port to Cable Plug communications. If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. Note: A Sink can still send Hard Reset Signaling at any time. Page 274 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.11 Message Discarding On receiving a received Message on SOP, the Protocol Layer Shall Discard any pending SOP* Messages. A received Message on SOP’/SOP’’ Shall Not cause any pending SOP* Messages to be Discarded. It is assumed that Messages using SOP’/SOP’’ constitute a simple request/response AMS, with the Cable Plug providing the response so there is no reason for a pending SOP* Message to be Discarded. There can only be one AMS between the Port Partners, and these also take priority over Cable Plug communications so a Message received on SOP will always cause a Message pending on SOP* to be Discarded. Table 6.74, "Message Discarding" for details of the Messages that Shall/ Shall Not be Discarded. Table 6.74 Message Discarding Message pending transmission Message received Message to be Discarded SOP SOP Outgoing Message SOP SOP’/SOP’’ Incoming Message SOP’ SOP Outgoing Message SOP’ SOP’ Incoming Message SOP’ SOP’’ Incoming Message SOP’’ SOP Outgoing Message SOP’’ SOP’ Incoming Message SOP’’ SOP’’ Incoming Message Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 275 6.12 State behavior 6.12.1 Introduction to state diagrams used in Chapter 6 The state diagrams defined in Section 6.12, "State behavior" are Normative and Shall define the operation of the Power Delivery Protocol Layer. Note: These state diagrams are not intended to replace a well written and robust design. Figure 6.57, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state and in some states "Actions on exit" a list of actions carried out on exiting the state. Figure 6.57 Outline of States Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&." The inverse of a condition is shown with a "NOT" in front of the condition. In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams. Figure 6.57, "Outline of States" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the referenced state. Figure 6.58 References to states Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the state it is referenced. As soon as the state is exited then the timer is no longer active. Timeouts of the timers are listed as conditions on state transitions. Conditions listed on state transitions will come from one of three sources: <Name of State> Actions on entry: “List of actions to carry out on entering the state” Actions on exit: “List of actions to carry out on exiting the state” <Name of reference state> (<DFP | UFP>) Page 276 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Messages received from the PHY Layer.  Events triggered within the Protocol Layer e.g., timer timeouts  Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.) 6.12.2 State Operation The following section details Protocol Layer State Operation when sending and receiving SOP* Packets. For each SOP’ Communication being sent and received there Shall be separate Protocol Layer Transmission and Protocol Layer Reception and Hard Reset State Machine instances, with their own counter and timer instances. When Chunking is supported there Shall be separate Chunked Tx, Chunked Tx, and Chunked Message Router State Machine instances. Soft Reset Shall only apply to the State Machine instances it is targeted at based on the type of SOP* Packet used to send the Soft_Reset Message. The Hard Reset State Machine (including Cable Reset) Shall apply simultaneously to all Protocol Layer State Machine instances active in the DFP, UFP and Cable Plug (if present). 6.12.2.1 Protocol Layer Chunking 6.12.2.1.1 Architecture of Device Including Chunking Layer The Chunking component resides in the Protocol Layer between the Policy Engine and Protocol Tx/Rx. Figure 6.59, "Chunking architecture Showing Message and Control Flow" illustrates the relationship between components. The Chunking Layer comprises three related state machines:  Chunked Rx.  Chunked Tx.  Chunked Message Router. Note: The consequence of this architecture is that the Policy Engine deals entirely in Unchunked Messages. It will not receive (and might not respond to) a Message until all the related chunks have been collated. If a PD device or Cable Plug has no requirement to handle any Message requiring more than one Chunk of any Extended Message, it May omit the Chunking Layer. In this case it Shall implement the ChunkingNotSupportedTimer to ensure compatible operation with partners which support Chunking (see Section 6.6.18.1, "ChunkingNotSupportedTimer" and Section 8.3.3.6, "Not Supported Message State Diagrams"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 277 Figure 6.59 Chunking architecture Showing Message and Control Flow 6.12.2.1.1.1 Optional Abort Mechanism Long Chunked Messages bring with them the potential problem that they could prevent urgent Messages from being transmitted in a timely manner. An Optional Abort mechanism is provided to remedy this problem. The Abort Flag referred to in the diagrams below May be set and examined by the Policy Engine. The specific means are left to the implementer. 6.12.2.1.1.2 Aborting Sending a Long-Chunked Message A long-Chunked Message being sent May be aborted by setting the Optional Abort Flag. The Message Shall be considered aborted when the Abort Flag is again cleared by the Chunked Tx state machine. 6.12.2.1.1.3 Aborting Receiving a Long-Chunked Message If the Optional Abort mechanism has been implemented, any Message sent while a Chunked Message receive is in progress will result in an error report being received by the Policy Engine, to indicate that the Message request has been Discarded. If the Message was urgent the Policy Engine might set the Abort Flag, which will result in the incoming Chunked Message being aborted. The Abort Flag being cleared by the Chunked Rx state machine indicates that the urgent Message can now be sent. 6.12.2.1.2 Chunked Rx State Diagram Figure 6.60, "Chunked Rx State Diagram" shows the state behavior for the Chunked Rx State Machine. This recognizes whether Chunked received Messages are involved and deals with requesting chunks when they are. It also performs validity checks on all Messages related to Chunking. Policy Engine Protocol Layer Rx Protocol Layer Tx PHY Layer Rp Control or Detection Chunked Rx Chunked Tx Chunking Protocol Layer Hard Reset Chunked Message Router AMS Notification Page 278 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.60 Chunked Rx State Diagram 6.12.2.1.2.1 RCH_Wait_For_Message_From_Protocol_Layer State The Chunked Rx State Machine Shall enter the RCH_Wait_For_Message_From_Protocol_Layer state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine clears the Extended Rx Buffer and clears the Optional Abort Flag. In the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine waits until the Chunked Message Router passes up a received Message. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  A non-Extended Message is passed up from the Chunked Message Router.  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are not doing Chunking, and the Message has its Chunked bit set to 0b. The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are doing Chunking, and the Message has its Chunked bit set to 1b. 6.12.2.1.2.2 RCH_Pass_Up_Message State On entry to the RCH_Pass_Up_Message state the Chunked Rx state machine Shall pass the received Message to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Message has been passed. Transmission Error from Protocol Layer | Message Received from Protocol Layer Other Message Received from Protocol Layer | ChunkSenderResponseTimer timeout RCH_Pass_Up_Message Actions on entry: Pass Message to Policy Engine RCH_Wait_For_Message_From_Protocol_Layer Actions on entry: Clear Extended Rx Buffer Clear Abort Flag RCH_Report_Error Actions on entry: Report Error to Policy Engine. If a Message was received, pass it to the Policy Engine. RCH_Processing_ Extended_Message Actions on entry: If first chunk: set Chunk_Number_Expected = 0 and Num bytes received = 0 If expected Chunk Number: Append data to Extended_Message_Buffer; Increment Chunk_Number_Expected and adjust Num bytes received. RCH_Requesting_Chunk Actions on entry: Send notification SRT_Stop to SenderResponseTimer State Machine. Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. RCH_Waiting_Chunk Actions on entry: Start ChunkSenderResponseTimer3 Send notification SRT_Start to SenderResponseTimer State Machine.3 Start Message not Complete Message Transmitted received from Protocol Layer Unexpected Chunk Number Reported Chunked != Chunking1 Received Non-Extended Message | (Received Extended Message & (Chunking1 = 0 & Chunked = 0) ) Message is Complete (Num bytes received >= specified Data Size)2 Message Passed Chunk Response Received from Protocol Layer Received Extended Message & (Chunking1 = 1 & Chunked = 1) Any Message Received and not in state RCH_Waiting_Chunk or RCH_Wait_For_Message_From_ Protocol_Layer Abort Flag Set Soft Reset occured | Exit from Hard Reset 1) Chunking is an internal state that is set to 1 if the ‘Unchunked Extended Messages Supported’ bit in either Source Capabilities or Request is 0. It defaults to 1 and is set after the first exchange of Source Capabilities and Request. It is also set to 1 for SOP’ or SOP’’ communication. 2) Additional bytes received over specified Data Size will be because of padding in the last chunk. 3) This state is responsible for starting two timers of similar length. The implementor Should mitigate against more than one of these timers resulting in recovery action. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 279 6.12.2.1.2.3 RCH_Processing_Extended_Message State On entry to the RCH_Processing_Extended_Message state the Chunked Rx state machine Shall:  If this is the first chunk:  Set Chunk_Number_Expected = 0.  Set Num bytes received = 0.  If chunk contains the expected Chunk Number:  Append its data to the Extended_Message_Buffer.  Increment Chunk_Number_Expected.  Adjust Num bytes received. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  The Message is complete (i.e., Num bytes received >= specified Data Size. Note: The inequality allows for padding bytes in the last chunk, which are not actually part of the Extended Mes- sage). The Chunked Rx State Machine Shall transition to the RCH_Requesting_Chunk state when:  The Message is not yet complete. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  An unexpected Chunk Number is received. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Optional Abort Flag is set. 6.12.2.1.2.4 RCH_Requesting_Chunk State On entry to the RCH_Requesting_Chunk state the Chunked Rx state machine Shall:  Send notification SRT_Stop to SenderResponseTimer state machine (see Section 8.3.3.1.1, "SenderResponseTimer State Diagram").  Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. The Chunked Rx State Machine Shall transition to the RCH_Waiting_Chunk state when:  Message Transmitted is received from the Protocol Layer. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  Transmission Error is received from the Protocol Layer, or  A Message is received from the Protocol Layer. 6.12.2.1.2.5 RCH_Waiting_Chunk State On entry to the RCH_Waiting_Chunk state the Chunked Rx state machine Shall:  Start the ChunkSenderResponseTimer.  Send notification SRT_Start to SenderResponseTimer state machine (see SSection 8.3.3.1.1, "SenderResponseTimer State Diagram"). The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  A Chunk is received from the Protocol Layer. Page 280 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  A Message, other than a Chunk, is received from the Protocol Layer, or  The ChunkSenderResponseTimer expires. 6.12.2.1.2.6 RCH_Report_Error State The Chunked Rx State Machine Shall enter the RCH_Report_Error state:  When any Message is received and the Chunked Rx State Machine is not in one of the states RCH_Waiting_Chunk or RCH_Wait_For_Message_From_Protocol_Layer. On entry to the RCH_Report_Error state the Chunked Rx state machine Shall:  Report the error to the Policy Engine.  If the state was entered because a Message was received, this Message Shall be passed to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The error has been reported.  Any Message received was passed to the Policy Engine. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 281 6.12.2.1.3 Chunked Tx State Diagram Figure 6.61, "Chunked Tx State Diagram" shows the state behavior for the Chunked Tx State Machine. This recognizes whether Chunked transmitted Messages are involved and deals with sending chunks and waiting for chunk requests when they are. It also performs validity checks on all related Messages related to Chunking. Figure 6.61 Chunked Tx State Diagram 6.12.2.1.3.1 TCH_Wait_For_Message_Request_From_Policy_Engine State The Chunked Tx State Machine Shall enter the TCH_Wait_For_Message_Request_From_Policy_Engine state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx state machine clears the Optional Abort Flag. In the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx State Machine waits until the Policy Engine sends it a Message Request. The Chunked Tx State Machine Shall transition to the TCH_Pass_Down_Message state when:  A non-Extended Message Request is received from the Policy Engine, or  A Message Request is received from the Policy Engine and the link is not Chunking. TCH_Sending_ Chunked_Message Actions on entry: TCH_ Wait_ For_Message_Request_From_Policy_Engine Actions on entry: Clear Abort Flag TCH_Pass_Down_Message Actions on entry: Pass Message to Protocol Layer TCH_Construct_ Chunked_Message Actions on entry: Construct Message Chunk and pass to Protocol Layer TCH_Wait_For_ Transmision_Complete Actions on entry: TCH_Prepare_To_Send_ Chunked_Message Actions on entry: 'Chunk Number To Send' = 0 TCH_Wait_Chunk_Request Actions on entry: Increment Chunk Number to Send Start ChunkSenderRequestTimer TCH_Report_Error Actions on entry: Report Error to Policy Engine Soft Reset occured | Exit from Hard Reset Start Non-Extended Message Request | Not Chunking Message Passed Message Transmitted received from Protocol Layer TCH_Message_Sent Actions on entry: Inform Policy Engine of Message Sent Any Message Received and not in state TCH_Wait_Chunk_Request Chunking & Extended Message Request Chunk Number Set Chunk Passed Message Transmitted from Protocol Layer & Not Last Chunk TCH_Message_Received Actions on entry: Clear Extended Message Buffers Pass Message to Chunked Rx Message passed to Chunked Rx Message Transmitted received from Protocol Layer & Last Chunk (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Supported Abort Flag Set Informed Chunk Request Rcvd & Chunk Number = Chunk Number to Send Reported Other Message Received (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Not Supported Tx Error from Protocol Layer ChunkSenderRequestTimer timeout & Chunk Number = 0 (Chunk Request Rcvd & Chunk Number != Chunk Number to Send) | (ChunkSenderRequestTimer timeout & Chunk Number > 0) Transmission Error Page 282 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Prepare_To_Send_Chunked_Message state when:  An Extended Message Request is received from the Policy Engine, and the link is Chunking. The Chunked Tx State Machine Shall Discard the Message Request and remain in the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer, and the Optional Abort Flag has not been implemented. The Chunked Tx State Machine Shall Discard the Message Request and enter the TCH_Report_Error state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer and the Optional Abort Flag has been implemented. 6.12.2.1.3.2 TCH_Pass_Down_Message State On entry to the TCH_Pass_Down_Message state the Chunked Tx State Machine Shall pass the Message to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Transmision_Complete state when:  The Message has been passed to the Protocol Layer. 6.12.2.1.3.3 TCH_Wait_For_Transmision_Complete State The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted has been received from the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.4 TCH_Message_Sent State On entry to the TCH_Message_Sent state the Chunked Tx State Machine Shall:  Inform the Policy Engine that the Message has been sent. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Policy Engine has been informed. 6.12.2.1.3.5 TCH_Prepare_To_Send_Chunked_Message State On entry to the TCH_Prepare_To_Send_Chunked_Message state the Chunked Tx State Machine Shall:  Set 'Chunk Number To Send' to zero. The Chunked Tx State Machine Shall transition to the TCH_Construct_Chunked_Message state when:  ‘Chunk Number To Send' has been set to zero. 6.12.2.1.3.6 TCH_Construct_Chunked_Message State On entry to the TCH_Construct_Chunked_Message state the Chunked Tx State Machine Shall:  Construct a Message Chunk and pass it to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Sending_Chunked_Message state when:  The Message Chunk has been passed to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 283  The Optional Abort Flag is set. 6.12.2.1.3.7 TCH_Sending_Chunked_Message State The Chunked Tx State Machine Shall transition to the TCH_Wait_Chunk_Request state when:  Message Transmitted is received from Protocol Layer and this was not the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted is received from Protocol Layer and this was the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.8 TCH_Wait_Chunk_Request State On entry to the TCH_Wait_Chunk_Request state the Chunked Tx State Machine Shall:  Increment Chunk Number to Send.  Start ChunkSenderRequestTimer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  A Chunk Request has been received and the Chunk Number does not equal Chunk Number to Send or  ChunkSenderRequestTimer has expired and Chunk Number is greater than zero. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  ChunkSenderRequestTimer has expired and Chunk Number equals zero. Note: This is the mechanism which allows the remote Port Partner or Cable Plug to omit the Chunking Layer. The Policy Engine will receive a Message Sent signal if the remote Port Partner or Cable Plug is present (GoodCRC Message received) but does not send a Chunk Request. After this the remote Port Partner will send a Not_Supported Message, or the Cable Plug will Ignore the Chunked Message. The Chunked Tx State Machine Shall transition to the TCH_Message_Received state when:  Any other Message than Chunk Request is received. 6.12.2.1.3.9 TCH_Message_Received State The Chunked Tx State Machine Shall enter the TCH_Message_Received state:  When any Message is received, and the Chunked Tx State Machine is not in the TCH_Wait_Chunk_Request state. On entry to the TCH_Message_Received state the Chunked Tx State Machine Shall:  Clear the Extended Message Buffers.  Pass the received Message to Chunked Rx Engine. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The received Message has been passed to the Chunked Rx Engine. 6.12.2.1.3.10 TCH_Report_Error State On entry to the TCH_Report_Error state the Chunked Tx State Machine Shall:  Report the error to the Policy Engine. Page 284 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The error has been reported. 6.12.2.1.4 Chunked Message Router State Diagram Figure 6.62, "Chunked Message Router State Diagram" shows the state behavior for the Chunked Message Router. This determines to which state machine an incoming Message is routed to (Chunked Rx, Chunked Tx or direct to Policy Engine). Figure 6.62 Chunked Message Router State Diagram 6.12.2.1.4.1 RTR_Wait_for_Message_From_Protocol_Layer State In the RTR_Wait_for_Message_From_Protocol_Layer state the Chunked Message Router waits until the Protocol Layer sends it a received Message. The Chunked Message Router Shall transition to the RTR_Rx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is not doing Tx Chunks. The Chunked Message Router Shall transition to the RTR_Tx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is doing Tx Chunks. 6.12.2.1.4.2 RTR_Rx_Chunks State On entry to the RTR_Rx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Rx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. RTR_Wait_for_Message_From_Protocol_Layer Actions on entry: RTR_Rx_Chunks Actions on entry: Send message to Rx Chunk Machine RTR_Tx_Chunks Actions on entry: Send message to Tx Chunk Machine Message Received from Protocol Layer & Not Doing Tx Chunks1 Message Received from Protocol Layer & Doing Tx Chunks1 Sent Soft Reset occured | Exit from Hard Reset Start Sent 1) Doing Tx Chunks means that Chunked Tx State Machine is not in the TCH_Wait_For_Message_Request_From_Policy_Engine state. 2) Messages are taken to include notification about transmission success or otherwise of Messages. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 285 6.12.2.1.4.3 RTR_Tx_Chunks State On entry to the RTR_Tx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Tx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. Page 286 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2 Protocol Layer Message Transmission 6.12.2.2.1 Common Protocol Layer Message Transmission State Diagram Figure 6.63, "Common Protocol Layer Message Transmission State Diagram" shows the state behavior, common between the Source and the Sink, for the Protocol Layer when transmitting a Message. Figure 6.63 Common Protocol Layer Message Transmission State Diagram 6.12.2.2.1.1 PRL_Tx_PHY_Layer_Reset State The Protocol Layer Shall enter the PRL_Tx_PHY_Layer_Reset state:  At startup.  As a result of a Soft Reset request being received by the PHY Layer.  On exit from a Hard Reset. On entry to the PRL_Tx_PHY_Layer_Reset state the Protocol Layer Shall reset the PHY Layer (clear any outstanding Messages and enable communications). The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  When the PHY Layer reset is complete. 6.12.2.2.1.2 PRL_Tx_Wait_for_Message_Request State In the PRL_Tx_Wait_for_Message_Request state the Protocol Layer waits until the Policy Engine directs it to send a Message.  On entry to the PRL_Tx_Wait_for_Message_Request state the Protocol Layer Shall reset the RetryCounter. Message request received from Policy Engine (except Soft Reset) Message sent to PHY Layer CRCReceiveTimer Timeout | Message discarded bus Idle2 GoodCRC response received from PHY Layer MessageID mismatch (RetryCounter ” nRetryCount) & not Cable Plug & small Extended Message3 (RetryCounter > nRetryCount) | Cable Plug | large Extended Message3 Policy Engine informed of Transmission Error MessageID match Policy Engine informed message sent PRL_Tx_Check_RetryCounter Actions on entry: If DFP or UFP increment and check RetryCounter PRL_Tx_Transmission_Error Actions on entry: Increment MessageIDCounter Inform Policy Engine of Transmission Error PRL_Tx_Construct_Message Actions on entry: Construct message Pass message to PHY Layer PRL_Tx_Wait_for_PHY_response Actions on entry: Initialize and run CRCReceiveTimer1 PRL_Tx_Match_MessageID Actions on entry: Match MessageIDCounter and response MessageID Soft Reset Message request received from Policy Engine Layer Reset Complete PRL_Tx_Message_Sent Actions on entry: Increment MessageIDCounter Inform Policy Engine message sent PRL_Tx_Layer_Reset_for_Transmit Actions on entry: Reset MessageIDCounter. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. PRL_Tx_Wait_for_Message_Request Actions on entry: Reset RetryCounter PRL_Tx_Discard_Message Actions on entry: If any message is currently awaiting transmission Discard4 and increment MessageID Counter Discarding complete Protocol Layer message reception in PRL_Rx_Store_MessageID state | Fast Role Swap signal transmitted | Fast Role Swap signal detected Start Soft Reset Message from PHY Layer | Exit from Hard Reset PRL_Tx_PHY_Layer_Reset Actions on entry: Reset PHY Layer PHY Layer reset complete 1) The CRCReceiveTimer is only started after the PHY has sent the message. If the message is not sent due to a busy channel, then the CRCReceiveTimer will not be started (see Section 6.6.1 “CRCReceiveTimer”). 2) This indication is sent by the PHY Layer when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). The CRCReceiveTimer is not running in this case since no message has been sent. 3) A “small” Extended Message is either an Extended Message with Data Size ζMaxExtendedMsgLegacyLen bytes or an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has been Chunked. A “large” Extended Message is an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has not been Chunked. 4) See Section 6.11 “Message Discarding” for details of when Messages are Discarded . Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 287 The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message request is received from the Policy Engine which is not a Soft_Reset Message. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Message request is received from the Policy Engine which is a Soft_Reset Message. 6.12.2.2.1.3 PRL_Tx_Layer_Reset_for_Transmit State On entry to the PRL_Tx_Layer_Reset_for_Transmit state the Protocol Layer Shall reset the MessageIDCounter. The Protocol Layer Shall transition Protocol Layer Message reception to the PRL_Rx_Wait_for_PHY_Message state (see Section 6.12.2.3.1, "PRL_Rx_Wait_for_PHY_Message state") in order to reset the stored MessageID. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The layer reset actions in this state have been completed. 6.12.2.2.1.4 PRL_Tx_Construct_Message State On entry to the PRL_Tx_Construct_Message state the Protocol Layer Shall construct the Message requested by the Policy Engine, or resend a previously constructed Message, and then pass this Message to the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_PHY_Response state when:  The Message has been sent to the PHY Layer. 6.12.2.2.1.5 PRL_Tx_Wait_for_PHY_Response State On entry to the PRL_Tx_Wait_for_PHY_Response state, once the Message has been sent, the Protocol Layer Shall initialize and run the CRCReceiveTimer (see Section 6.6.1, "CRCReceiveTimer"). The Protocol Layer Shall transition to the PRL_Tx_Match_MessageID state when:  A GoodCRC Message response is received from the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The CRCReceiveTimer times out.  Or the PHY Layer indicates that a Message has been Discarded due to the channel being busy but the channel is now Idle (see Section 5.7, "Collision Avoidance"). 6.12.2.2.1.6 PRL_Tx_Match_MessageID State On entry to the PRL_Tx_Match_MessageID state the Protocol Layer Shall compare the MessageIDCounter and the MessageID of the received GoodCRC Message. The Protocol Layer Shall transition to the PRL_Tx_Message_Sent state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message match. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message do not match. 6.12.2.2.1.7 PRL_Tx_Message_Sent State On entry to the PRL_Tx_Message_Sent state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine that the Message has been sent. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed that the Message has been sent. Page 288 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.1.8 PRL_Tx_Check_RetryCounter State On entry to the PRL_Tx_Check_RetryCounter state the Protocol Layer in a DFP or UFP Shall increment the value of the RetryCounter and then check it in order to determine whether it is necessary to retry sending the Message. Note: Cable Plugs do not retry Messages and so do not use the RetryCounter. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state in order to retry Message sending when:  RetryCounter ≤ nRetryCount and  This is not a Cable Plug and  This is an Extended Message with Data Size ≤ MaxExtendedMsgLegacyLen or  This is an Extended Message that has been Chunked. The Protocol Layer Shall transition to the PRL_Tx_Transmission_Error state when:  RetryCounter > nRetryCount or  This is a Cable Plug, which does not retry.  This is an Extended Message with Data Size > MaxExtendedMsgLegacyLen that has not been Chunked. 6.12.2.2.1.9 PRL_Tx_Transmission_Error State On entry to the PRL_Tx_Transmission_Error state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine of the transmission error. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed of the transmission error. 6.12.2.2.1.10 PRL_Tx_Discard_Message State Protocol Layer Message transmission Shall enter the PRL_Tx_Discard_Message state whenever:  Protocol Layer Message reception receives an incoming Message or  The Fast Role Swap Request is being transmitted (see Section 5.8.5.6, "Fast Role Swap Transmission")  The Fast Role Swap Request is detected (see Section 5.8.6.3, "Fast Role Swap Detection"). On entry to the PRL_Tx_Discard_Message state, if there is a Message queued awaiting transmission, the Protocol Layer Shall Discard the Message according to the rules in Section 6.11, "Message Discarding" and increment the MessageIDCounter. The Protocol Layer Shall transition to the PRL_Tx_PHY_Layer_Reset state when:  Discarding is complete i.e., the Message queue is empty. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 289 6.12.2.2.2 Source Protocol Layer Message Transmission State Diagram Figure 6.64, "Source Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Source when transmitting a Message. Figure 6.64 Source Protocol Layer Message Transmission State Diagram PRL_Tx_Wait_for_Message_Request PRL_Tx_Src_Sink_Tx Actions on entry: Set Rp = SinkTxOk End of AMS notification received from Policy Engine Start of AMS notification received from Policy Engine PRL_Tx_Src_Pending Actions on entry: Start SinkTxTimer PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending & SinkTxTimer timeout Message pending (except Soft Reset) & SinkTxTimer timeout Rp set PRL_Tx_Src_Source_Tx Actions on entry: Set Rp = SinkTxNG Message request from Policy Engine Page 290 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.2.1 PRL_Tx_Src_Sink_Tx State In the PRL_Tx_Src_Sink_Tx state the Source sets Rp to SinkTxOK allowing the Sink to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Sink_Tx state when:  A notification is received from the Policy Engine that the end of an AMS has been reached. On entry to the PRL_Tx_Src_Sink_Tx state the Protocol Layer Shall request the PHY Layer to Rp to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  Rp has been set. 6.12.2.2.2.2 PRL_Tx_Src_Source_Tx State In the PRL_Tx_Src_Source_Tx state the Source sets Rp to SinkTxNG allowing the Source to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Source_Tx state when:  A notification is received from the Policy Engine that an AMS will be starting. On entry to the PRL_Tx_Src_Source_Tx state the Protocol Layer Shall set Rp to SinkTxNG. The Protocol Layer Shall transition to the PRL_Tx_Src_Pending state when:  A Message request is received from the Policy Engine. 6.12.2.2.2.3 PRL_Tx_Src_Pending State In the PRL_Tx_Src_Pending state the Protocol Layer has a Message buffered ready for transmission. On entry to the PRL_Tx_Src_Pending state the SinkTxTimer Shall be initialized and run. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The pending Message request from the Policy Engine is not a Soft_Reset Message and  The SinkTxTimer times out. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  The pending Message request from the Policy Engine is a Soft_Reset Message and  The SinkTxTimer times out. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 291 6.12.2.2.3 Sink Protocol Layer Message Transmission State Diagram Figure 6.65, "Sink Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Sink when transmitting a Message. Figure 6.65 Sink Protocol Layer Message Transmission State Diagram 6.12.2.2.3.1 PRL_Tx_Snk_Start_of_AMS State In the PRL_Tx_Snk_Start_of_AMS state the Protocol Layer waits for the first Message in a Sink initiated AMS. The Protocol Layer in a Sink Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Snk_Start_of_AMS state when:  A notification is received from the Policy Engine that the next Message the Sink will send is the start of an AMS. The Protocol Layer Shall transition to the PRL_Tx_Snk_Pending state when:  A Message request is received from the Policy Engine. PRL_Tx_Wait_for_Message_Request First Message in AMS notification received from Policy Engine PRL_Tx_Snk_Pending Actions on entry: PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending Message pending (except Soft Reset) & Rp = SinkTxOk PRL_Tx_Snk_Start_of_AMS Actions on entry: Message Request from Policy Engine Page 292 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.3.2 PRL_Tx_Snk_Pending State In the PRL_Tx_Snk_Pending state the Protocol Layer has the first Message in a Sink initiated AMS ready to send and is waiting for Rp to transition to SinkTxOK before sending the Message. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message is Pending that is not a Soft_Reset Message and  Rp is set to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Soft_Reset Message is pending. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 293 6.12.2.3 Protocol Layer Message Reception Figure 6.66, "Protocol layer Message reception" shows the state behavior for the Protocol Layer when receiving a Message. Figure 6.66 Protocol layer Message reception 6.12.2.3.1 PRL_Rx_Wait_for_PHY_Message state The Protocol Layer Shall enter the PRL_Rx_Wait_for_PHY_Message state:  At startup.  As a result of a Soft Reset request from the Policy Engine.  On exit from a Hard Reset. In the PRL_Rx_Wait_for_PHY_Message state the Protocol Layer waits until the PHY Layer passes up a received Message. The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC state when:  A Message is passed up from the PHY Layer. The Protocol Layer Shall transition to the PRL_Rx_Layer_Reset_for_Receive state when:  A Soft_Reset Message is received from the PHY Layer. Message received from PHY (except Soft Reset) Message passed to Policy Engine (GoodCRC sent | Message discarded bus Idle1) MessageID <> stored MessageID | no stored value MessageID = stored MessageID Start PRL_Rx_Send_GoodCRC Actions on entry: Send GoodCRC message to PHY PRL_Rx_Store_MessageID Actions on entry: Protocol Layer message transmission transitions to PRL_Tx_Discard_Message state2. Store new MessageID Pass message to Policy Engine3 PRL_Rx_Wait_for_PHY_message Actions on entry: PRL_Rx_Check_MessageID Actions on entry: If there is a stored value compare MessageID with stored value. Soft Reset Message received from PHY Soft Reset complete PRL_Rx_Layer_Reset_for_Receive Actions on entry: Reset MessageIDCounter and clear stored MessageID value Protocol Layer message transmission transitions to PRL_Tx_PHY_Layer_Reset state. Soft Reset request from Policy Engine | Exit from Hard Reset Message discarded bus Idle1 1) This indication is sent by the PHY when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). Two alternate allowable transitions are shown. 2) In the case of a Ping message being received, in order to maintain robust communications in the presence of collisions, the outgoing message Should Not be Discarded. 3) See Section 6.11 “Message Discarding” for details of when Messages are discarded. Page 294 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.3.2 PRL_Rx_Layer_Reset_for_Receive state On entry to the PRL_Rx_Layer_Reset_for_Receive state the Protocol Layer Shall reset the MessageIDCounter and clear the stored MessageID. The Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Wait_for_Message_Request state (see Section 6.12.2.2.1.2, "PRL_Tx_Wait_for_Message_Request State"). The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC State when:  The Soft Reset actions in this state have been completed. 6.12.2.3.3 PRL_Rx_Send_GoodCRC state On entry to the PRL_Rx_Send_GoodCRC state the Protocol Layer Shall construct a GoodCRC Message and request the PHY Layer to transmit it. The Protocol Layer Shall transition to the PRL_Rx_Check_MessageID state when:  The GoodCRC Message has been passed to the PHY Layer. When the PHY Layer indicates that a Message has been Discarded due to CC being busy but CC is now Idle (see Section 5.7, "Collision Avoidance"), the Protocol Layer Shall either:  Transition to the PRL_Rx_Check_MessageID state or  Transition to the PRL_Rx_Wait_for_PHY_Message state. 6.12.2.3.4 PRL_Rx_Check_MessageID state On entry to the PRL_Rx_Check_MessageID state the Protocol Layer Shall compare the MessageID of the received Message with its stored value if a value has previously been stored. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The MessageID of the received Message equals the stored MessageID value since this is a Message retry which Shall be Discarded. The Protocol Layer Shall transition to the PRL_Rx_Store_MessageID state when:  The MessageID of the received Message does not equal the stored MessageID value since this is a new Message or  This is the first received Message and no MessageID value is currently stored. 6.12.2.3.5 PRL_Rx_Store_MessageID state On entry to the PRL_Rx_Store_MessageID state the Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Discard_Message state, replace the stored value of MessageID with the value of MessageID in the received Message and pass the Message up to the Policy Engine. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The Message has been passed up to the Policy Engine. 6.12.2.4 Hard Reset operation Figure 6.57, "Outline of States" shows the state behavior for the Protocol Layer when receiving a Hard Reset or Cable Reset request from the Policy Engine or Hard Reset Signaling or Cable Reset Signaling from the PHY Layer (see also Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 295 Figure 6.67 Hard/Cable Reset 6.12.2.4.1 PRL_HR_Reset_Layer state The PRL_HR_Reset_Layer State defines the mode of operation of both the Protocol Layer transmission and reception state machines during a Hard Reset or Cable Reset. During Hard Reset no USB Power Delivery Protocol Messages are sent or received; only Hard Reset Signaling is present after which the communication channel is assumed to have been disabled by the PHY Layer until completion of the Hard Reset. During Cable Reset no USB Power Delivery Protocol Messages are sent to or received by the Cable Plug but other USB Power Delivery communication May continue. The Protocol Layer Shall enter the PRL_HR_Reset_Layer state from any other state when:  A Hard Reset Request is received from the Policy Engine or  Hard Reset Signaling is received from the PHY Layer or Hard Reset request received from Policy Engine2 | Cable Reset request received from Policy Engine4 | Hard Reset signalling received By PHY Layer | Cable Reset signalling received By PHY Layer3 PHY Hard Reset request sent | PHY Cable Reset request sent Hard Reset complete from Policy Engine | Cable Reset complete from Policy Engine Physical Layer informed PRL_HR_Request_Hard_Reset Actions on entry: Request PHY to perform a Hard Reset or Cable Reset PRL_HR_Reset_Layer Actions on entry: Reset MessageIDCounter. Protocol Layer message transmission transitions to PRL_Tx_Wait_For_Message_Request state. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. Protocol Layer reset complete & (Hard Reset was Initiated by Policy Engine | Cable Reset was Initiated by Policy Engine) Policy Engine informed Protocol Layer reset complete & (Hard Reset was initiated by Port Partner | Cable Reset received by Cable Plug) PRL_HR_Indicate_Hard_Reset Actions on entry: Inform the Policy Engine of the Hard Reset or Cable Reset Exit from Hard Reset Policy Engine informed PRL_HR_PHY_Hard_Reset_Requested Actions on entry: Inform Policy Engine Hard Reset or Cable Reset request has been sent PRL_HR_Wait_For_PE_Hard_Reset_Complete Actions on entry: Wait for Hard Reset or Cable Reset complete indication from Policy Engine. PRL_HR_PE_Hard_Reset_Complete Actions on entry: Inform Physical Layer Hard Reset or Cable Reset is complete PRL_HR_Wait_For_PHY_Hard_Reset_Complete Actions on entry: Start HardResetCompleteTimer Wait for Hard Reset or Cable Reset complete indication from PHY Hard Reset complete from PHY | Cable Reset complete from PHY | HardResetCompleteTimer timeout1 1) If the HardResetCompleteTimer timeout occurs this means that the PHY is still waiting to send the Hard Reset due to a non-idle channel. This condition will be cleared once the PE Hard Reset is completed. 2) Cable Plugs do not generate Hard Reset signaling but are required to monitor for Hard Reset signaling between the Port Partners and respond by resetting. 3) Cable Reset signaling is only recognized by a Cable Plug. 4) Cable Reset signaling cannot be generated by Cable Plugs. Page 296 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Cable Reset Request is received from the Policy Engine or  Cable Reset Signaling is received from the PHY Layer. On entry to the PRL_HR_Reset_Layer state the Protocol Layer Shall reset the MessageIDCounter. It Shall also reset the states of the Protocol Layer transmission and reception state machines to their starting points. The Protocol Layer transmission state machine Shall transition to the PRL_Tx_Wait_for_Message_Request state. The Protocol Layer reception state machine Shall transition to the PRL_Rx_Wait_for_PHY_Message state. The Protocol Layer Shall transition to the PRL_HR_Request_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has originated from the Policy Engine or  The Cable Reset request has originated from the Policy Engine. The Protocol Layer Shall transition to the PRL_HR_Indicate_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has been passed up from the PHY Layer or  A Cable Reset request has been passed up from the PHY Layer (Cable Plug only). 6.12.2.4.2 PRL_HR_Indicate_Hard_Reset state On entry to the PRL_HR_Indicate_Hard_Reset state the Protocol Layer Shall indicate to the Policy Engine that either Hard Reset Signaling or Cable Reset Signaling has been received. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when:  The indication to the Policy Engine has been sent. 6.12.2.4.3 PRL_HR_Request_Hard_Reset state On entry to the PRL_HR_Request_Hard_Reset state the Protocol Layer Shall request the PHY Layer to send either Hard Reset Signaling or Cable Reset Signaling. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state when:  The PHY Layer Hard Reset Signaling request has been sent or  The PHY Layer Cable Reset Signaling request has been sent. 6.12.2.4.4 PRL_HR_Wait_for_PHY_Hard_Reset_Complete state In the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state the Protocol Layer Shall start the HardResetCompleteTimer and wait for the PHY Layer to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PHY_Hard_Reset_Requested state when:  A Hard Reset complete indication is received from the PHY Layer or  A Cable Reset complete indication is received from the PHY Layer or  The HardResetCompleteTimer times out. 6.12.2.4.5 PRL_HR_PHY_Hard_Reset_Requested state On entry to the PRL_HR_PHY_Hard_Reset_Requested state the Protocol Layer Shall inform the Policy Engine that the PHY Layer has been requested to perform a Hard Reset or Cable Reset. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 297  The Indication to the Policy Engine has been sent. 6.12.2.4.6 PRL_HR_Wait_for_PE_Hard_Reset_Complete state In the PRL_HR_Wait_for_PE_Hard_Reset_Complete state the Protocol Layer Shall wait for the Policy Engine to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PE_Hard_Reset_Complete state when:  A Hard Reset complete indication is received from the Policy Engine or  A Cable Reset complete indication is received from the Policy Engine. 6.12.2.4.7 PRL_HR_PE_Hard_Reset_Complete On entry to the PRL_HR_PE_Hard_Reset_Complete state the Protocol Layer Shall inform the PHY Layer that the Hard Reset or Cable Reset is complete. The Protocol Layer Shall exit from the Hard Reset and return to normal operation when:  The PHY Layer has been informed that the Hard Reset is complete so that it will re-enable the communications channel. If Hard Reset Signaling is still pending due to a non-Idle channel this Shall be cleared and not sent or  The PHY Layer has been informed that the Cable Reset is complete. Page 298 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.3 List of Protocol Layer States Table 6.75, "Protocol Layer States" lists the states used by the various state machines. Table 6.75 Protocol Layer States State Name Section Protocol Layer Message Transmission Common Protocol Layer Message Transmission PRL_Tx_PHY_Layer_Reset Section 6.12.2.2.1.1 PRL_Tx_Wait_for_Message_Request Section 6.12.2.2.1.2 PRL_Tx_Layer_Reset_for_Transmit Section 6.12.2.2.1.3 PRL_Tx_Construct_Message Section 6.12.2.2.1.4 PRL_Tx_Wait_for_PHY_Response Section 6.12.2.2.1.5 PRL_Tx_Match_MessageID Section 6.12.2.2.1.6 PRL_Tx_Message_Sent Section 6.12.2.2.1.7 PRL_Tx_Check_RetryCounter Section 6.12.2.2.1.8 PRL_Tx_Transmission_Error Section 6.12.2.2.1.9 PRL_Tx_Discard_Message Section 6.12.2.2.1.10 Source Protocol Layer Message Transmission PRL_Tx_Src_Sink_Tx Section 6.12.2.2.2.1 PRL_Tx_Src_Source_Tx Section 6.12.2.2.2.2 PRL_Tx_Src_Pending Section 6.12.2.2.2.3 Sink Protocol Layer Message Transmission PRL_Tx_Snk_Start_of_AMS Section 6.12.2.2.3.1 PRL_Tx_Snk_Pending Section 6.12.2.2.3.2 Protocol Layer Message Reception PRL_Rx_Wait_for_PHY_Message Section 6.12.2.3.1 PRL_Rx_Layer_Reset_for_Receive Section 6.12.2.3.2 PRL_Rx_Send_GoodCRC Section 6.12.2.3.3 PRL_Rx_Check_MessageID Section 6.12.2.3.4 PRL_Rx_Store_MessageID Section 6.12.2.3.5 Hard Reset Operation PRL_HR_Reset_Layer Section 6.12.2.4.1 PRL_HR_Indicate_Hard_Reset Section 6.12.2.4.2 PRL_HR_Request_Hard_Reset Section 6.12.2.4.3 PRL_HR_Wait_for_PHY_Hard_Reset_Complete Section 6.12.2.4.4 PRL_HR_PHY_Hard_Reset_Requested Section 6.12.2.4.5 PRL_HR_Wait_for_PE_Hard_Reset_Complete Section 6.12.2.4.6 PRL_HR_PE_Hard_Reset_Complete Section 6.12.2.4.7 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 299 Chunking Chunked Rx RCH_Wait_For_Message_From_Protocol_Layer Section 6.12.2.2.1.1 RCH_Pass_Up_Message Section 6.12.2.2.1.1 RCH_Processing_Extended_Message Section 6.12.2.2.1.1 RCH_Requesting_Chunk Section 6.12.2.2.1.1 RCH_Waiting_Chunk Section 6.12.2.2.1.1 RCH_Report_Error Section 6.12.2.2.1.1 Chunked Tx TCH_Wait_For_Message_Request_From_Policy_Engine Section 6.12.2.1.3.1 TCH_Pass_Down_Message Section 6.12.2.1.3.2 TCH_Wait_For_Transmision_Complete Section 6.12.2.1.3.3 TCH_Message_Sent Section 6.12.2.1.3.4 TCH_Prepare_To_Send_Chunked_Message Section 6.12.2.1.3.5 TCH_Construct_Chunked_Message Section 6.12.2.1.3.6 TCH_Sending_Chunked_Message Section 6.12.2.1.3.7 TCH_Wait_Chunk_Request Section 6.12.2.1.3.8 TCH_Message_Received Section 6.12.2.1.3.9 TCH_Report_Error Section 6.12.2.1.3.10 Chunked Message Router RTR_Wait_for_Message_From_Protocol_Layer Section 6.12.2.1.4.1 RTR_Rx_Chunks Section 6.12.2.1.4.2 RTR_Tx_Chunks Section 6.12.2.1.4.3 Table 6.75 Protocol Layer States (Continued) State Name Section Page 300 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13 Message Applicability The following tables outline the Messages supported by a given Port, depending on its capability. When a Message is supported the feature and the AMS implied by the Message Shall also be supported. The abbreviations in Table 6.76, "Message Applicability Abbreviations" are used in this section to denote the level of support required. For the case of Conditional Normative a note has been added to indicate the condition. "CN/" notation is used to indicate the level of support when the condition is not present. "R/" and "O/" notation is used to indicate the response when the Recommended or Optional Message is not supported. Note: Where NS/R/NK is indicated for Received Messages this Shall apply to the PE_CBL_Ready, PE_SNK_Ready or PE_SRC_Ready states only since unexpected Messages received during an AMS are Pro- tocol Errors (see Section 6.8.1, "Soft Reset and Protocol Error"). This section covers Control Message and Data Message support for Sources, Sink and Cable Plugs. It also covers VDM Command support for DFPs, UFPs and Cable Plugs. Table 6.76 Message Applicability Abbreviations Abbreviation Meaning Description N Normative Shall be supported by this Port/Cable Plug. CN Conditional Normative Shall supported by a given Port/Cable Plug based on features. R Recommended Should be supported by this Port/Cable Plug. O Optional May be supported by this Port/Cable Plug. NS Not Supported Shall result in a Not_Supported Message response by this Port/Cable Plug when received. I Ignore Shall be Ignored by this Port/Cable Plug when received. NK NAK This Port/Cable Plug Shall return Responder NAK to this Command when received. NA Not allowed Shall Not be transmitted by this Port/Cable Plug. DR Don’t Recognize There Shall be no response at all (i.e., not even a GoodCRC Message) from this Port/Cable Plug when received. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 301 6.13.1 Applicability of Control Messages Table 6.77, "Applicability of Control Messages" details Control Messages that Shall/Should/Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.77 Applicability of Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 Transmitted Message Accept N N N N Data_Reset CN10/R CN10/R NA NA DR_Swap O O N NA NA FR_Swap NA NA R NA NA Get_Country_Codes CN7/NA CN7/NA NA NA Get_PPS_Status NA CN6 NA NA Get_Sink_Cap R NA N NA NA Get_Sink_Cap_Extended R NA R NA NA Get_Source_Cap NA R N NA NA Get_Source_Cap_Extended NA R R NA NA Get_Source_Info NA R R NA NA Get_Revision R R NA NA Get_Status R R NA NA GoodCRC N N N N GotoMin (Deprecated) NA NA NA NA Not_Supported N N NA NA Ping (Deprecated) NA NA NA NA PR_Swap NA NA N NA NA PS_RDY N CN1/NA N NA NA Reject N O O O CN10/NA NA Soft_Reset N N NA NA VCONN_Swap R R NA NA Wait O NA O O NA NA 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Page 302 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Received Message Accept N N N N I I Data_Reset CN10/R CN10/R I I DR_Swap O/NS O/NS N I I FR_Swap NS NS CN4/NS I I Get_Country_Codes CN7/NS CN7/NS I I Get_PPS_Status CN6/NS NS I I Get_Sink_Cap NS N N I I Get_Sink_Cap_Extended NS N N I I Get_Source_Cap N NS N I I Get_Source_Cap_Extended CN2/NS NS CN2/NS I I Get_Source_Info CN11 NS N I I Get_Revision N N O/I O/I Get_Status CN3/NS CN3/NS CN3/NS CN8/I I GoodCRC N N N N GotoMin (Deprecated) NS NS I I Not_Supported N N CN8/I I Ping (Deprecated) NS NS/I I I PR_Swap NS NS N I I PS_RDY CN1/NS N N I I Reject CN5/NS N N N I I Soft_Reset N N N N VCONN_Swap CN1/ NS CN1/ NS I I Wait CN5/NS N N N I I Table 6.77 Applicability of Control Messages (Continued) Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 303 6.13.2 Applicability of Data Messages Table 6.78, "Applicability of Data Messages" details Data Messages (except for VDM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.78 Applicability of Data Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 Transmitted Message Source_Capabilities N NA N NA NA NA Request NA N NA NA NA Get_Country_Info CN5/O CN5/O NA NA NA BIST N1 N1 NA NA NA Sink_Capabilities NA N N NA NA NA Battery_Status CN2 CN2 NA NA NA Alert CN11/R CN11/R NA NA NA Enter_USB CN7/O CN7/O NA NA NA EPR_Request NA CN9 NA NA NA EPR_Mode CN9 CN9 NA NA NA Source_Info CN10 NA N NA NA NA Revision N N CN12/O/I NA O Received Message Source_Capabilities NS N N I I I Request N NS I I I Get_Country_Info CN5/NS CN5/NS I I I BIST N1 N1 N1 N1 N1 Sink_Capabilities CN4 NS CN4 I I I Battery_Status CN3/NS CN3/NS I I I Alert R/NS R/NS I I I Enter_USB CN7/O CN7/O CN8/I CN8/I I 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Page 304 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 EPR_Request CN9 NA I I I EPR_Mode CN9 CN9 I I I Source_Info NA N N I I I Revision N N I I I Table 6.78 Applicability of Data Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 305 6.13.3 Applicability of Extended Messages Table 6.79, "Applicability of Extended Messages" details Extended Messages (except for VDEM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual- Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.79 Applicability of Extended Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 Transmitted Message Battery_Capabilities CN1/NA CN1/NA NA NA NA Country_Codes CN10/NA CN10/NA NA NA NA Country_Info CN10/NA CN10/NA NA NA NA EPR_Source_Capabilities CN14/NA NA CN14/NA NA NA NA EPR_Sink_Capabilities NA CN14/NA CN14/NA NA NA NA Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NA CN7/NA NA NA NA Firmware_Update_Response CN7/NA CN7/NA CN7/NA O NA Get_Battery_Cap R R NA NA NA Get_Battery_Status R R NA NA NA Get_Manufacturer_Info R R NA NA NA Manufacturer_Info R R R NA NA PPS_Status CN8/NA NA NA NA NA Security_Request CN6/NA CN6/NA NA NA NA Security_Response CN6/NA CN6/NA CN6/NA NA NA Sink_Capabilities_Extended NA N N NA NA NA Source_Capabilities_Extended R NA R NA NA NA 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 306 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Status CN15/R CN15/R CN15/R CN12/NA CN12/NA NA Vendor_Defined_Extended O O O O O Received Message Battery_Capabilities CN4/NS CN4/NS I I I Country_Codes CN10/NS CN10/NS I I I Country_Info CN10/NS CN10/NS I I I EPR_Source_Capabilities NS CN14/NS CN14/NS I I I EPR_Sink_Capabilities CN14/NS NS CN14/NS I I I Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NS CN7/NS CN7/I O I Firmware_Update_Response CN7/NS CN7/NS I I I Get_Battery_Cap CN1/NS CN1/NS I I I Get_Battery_Status CN1/NS CN1/NS I I I Get_Manufacturer_Info R/NS R/NS R/I I I Manufacturer_Info CN5/NS CN5/NS I I I PPS_Status NS CN9/NS I I I Security_Request CN6/NS CN6/NS CN6/I I I Security_Response CN6/NS CN6/NS I I I Sink_Capabilities_Extended CN11/NS NS CN11/NS I I I Source_Capabilities_Extended NS CN2/NS CN2/NS I I I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 307 Status CN33/NS CN3/NS I I I Vendor_Defined_Extended O/NS O/NS O/I O/I O/I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 308 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.4 Applicability of Extended Control Messages Table 6.80, "Applicability of Extended Control Messages" details Extended Control Messages that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.80 Applicability of Extended Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD2 Transmitted Message EPR_Get_Source_Cap NA CN1 CN1 NA NA EPR_Get_Sink_Cap CN1 NA CN1 NA NA EPR_KeepAlive NA CN1 NA NA EPR_KeepAlive_Ack CN1 NA NA NA Received Message EPR_Get_Source_Cap CN1 NS CN1 I I EPR_Get_Sink_Cap NS CN1 CN1 I I EPR_KeepAlive CN1 NS I I EPR_KeepAlive_Ack NS CN1 I I 1) Shall be supported by products that support EPR Mode. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 309 6.13.5 Applicability of Structured VDM Commands Table 6.81, "Applicability of Structured VDM Commands" details Structured VDM Commands that Shall/Should/ Shall Not be transmitted and received by a DFP, UFP, Cable Plug or VPD. If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. Table 6.81 Applicability of Structured VDM Commands Command Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD4 Transmitted Command Request Discover Identity CN1,6/R R2 NA NA NA Discover SVIDs CN1/O O NA NA NA Discover Modes CN1/O O NA NA NA Enter Mode CN1/NA NA NA NA NA Exit Mode CN1/NA NA NA NA NA Attention O O NA NA NA Received Command Request/Transmitted Command Response Discover Identity CN5,6/R/ NK3 CN1,6/R/ NK3 N I N Discover SVIDs O/NK3 CN1/NK3 CN1/NK I NK Discover Modes O/NK3 CN1/NK3 CN1/NK I NK Enter Mode NK3 CN1/NK3 CN1/NK O NK Exit Mode NK3 CN1/NK3 CN1/NK O NK Attention O/I3 O/I3 I I I 1) Shall be supported when Modal Operation is supported. 2) May be transmitted by a UFP/Source during discovery (see Section 6.4.4.3.1, "Discover Identity" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 3) If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. 4) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT- VPD Shall only take place when not Connected to a Charger. 5) Shall be supported by products with more than one DFP. 6) Shall be supported by products that support [USB4]. Page 310 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.6 Applicability of Reset Signaling Table 6.82, "Applicability of Reset Signaling" details the Reset that Shall/Should/ Shall Not be transmitted and received by a DFP/UFP or Cable Plug. 6.13.7 Applicability of Fast Role Swap Request Table 6.83, "Applicability of Fast Role Swap Request" details the Fast Role Swap Request that Shall/Should/ Shall Not be transmitted and received by a Source or Sink. Table 6.82 Applicability of Reset Signaling Reset Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD2 Transmitted Message/Signaling Soft_Reset N N NA NA NA Hard Reset N N NA NA NA Cable Reset CN1 NA NA NA NA Received Message/Signaling Soft_Reset N N N N N Hard Reset N N N N N Cable Reset DR DR N N N 1) Shall be supported when transmission of SOP’ Packets are supported, and the Port can supply VCONN. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Table 6.83 Applicability of Fast Role Swap Request Command Type Source Sink Dual-Role Power Transmitted Message/Signaling Fast Role Swap NA NA R Received Message/Signaling Fast Role Swap NA NA R Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 311 6.14 Value Parameters Table 6.84, "Value Parameters" contains value parameters used in this section. Table 6.84 Value Parameters Parameter Description Value Unit Reference MaxExtendedMsgLen Maximum length of an Extended Message as expressed in the Data Size field. 260 Byte Section 6.2.1.2 MaxExtendedMsgChunkLen Maximum length of an Extended Message Chunk. 26 Byte Section 6.2.1.2 MaxExtendedMsgLegacyLen Maximum length of an Extended Message that can be sent without Chunking. 26 Byte Section 6.2.1.2
7 - Power Supply. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 312)
Page 312 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7 Power Supply 7.1 Source Requirements 7.1.1 Behavioral Aspects A PDUSB Source exhibits the following behaviors:  Shall supply [USB Type-C 2.4] USB Type-C® current to VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS voltage transitions as bound by undershoot, overshoot and transition time requirements. 7.1.2 Source Bulk Capacitance The Source bulk capacitance Shall Not be placed between the transceiver isolation impedance and the USB receptacle. The Source bulk capacitance consists of C1 and C2 as shown in Figure 7.1, "Placement of Source Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect might also be part of the circuit implemented by the Source to limit its VBUS Output Voltage Limit (OVL) as described in Section 7.1.7.5, "Output Voltage Limit". Though a Source Shall limit its output voltage, a Sink Shall implement Sink OVP as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. If the power supply is shared across multiple ports, the bulk capacitance is defined as cSrcBulkShared. If the power supply is dedicated to a single Port, the minimum bulk capacitance is defined as cSrcBulk. The Source bulk capacitance is allowed to change for a newly Negotiated power level. The capacitance change Shall occur before the Source is ready to operate at the new power level. During a Power Role Swap, the Initial Source Shall transition to Swap Standby before operating as the New Sink. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.1 Placement of Source Bulk Capacitance 7.1.3 Types of Sources Consistent with the Power Data Objects discussed in Section 6.4.1, "Capabilities Message", the power supply types that are available as Sources in a USB Power Delivery System are:  The Fixed Supply PDO exposes well-regulated fixed voltage power supplies. Sources Shall support at least one Fixed Supply capable of supplying vSafe5V. The output voltage of a Fixed Supply Shall remain C2 Ohmic Interconnect GND SHIELD VBUS ... Data Lines GND SHIELD VBUS ... Data Lines SOURCE CABLE C1 Power Supply Source Bulk Capacitance OVL Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 313 within the range defined by the relative tolerance vSrcNew and the absolute band vSrcValid as listed in Table 7.23, "Source Electrical Parameters" and described in Section 7.1.8, "Output Voltage Tolerance and Range".  The Variable Supply (non-Battery) PDO exposes less well-regulated Sources. The output voltage of a Variable Supply (non-Battery) Shall remain within the absolute maximum output voltage and the absolute minimum output voltage exposed in the Variable Supply PDO.  The Battery Supply PDO exposes Batteries than can be connected directly as a Source to VBUS. The output voltage of a Battery Supply Shall remain within the absolute maximum output voltage and the absolute minimum output exposed in the Battery Supply PDO.  The Programmable Power Supply (PPS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the Programmable Power Supply Shall remain within a range defined by the relative tolerance vPpsNew and the absolute band vPpsValid.  The Adjustable Voltage Supply (AVS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the AVS Shall remain within a range defined by the relative tolerance vAvsNew and the absolute band vAvsValid. 7.1.4 Source Transitions 7.1.4.1 Fixed Supply 7.1.4.1.1 Fixed Supply Positive Voltage Transitions The Source Shall transition VBUS from the starting voltage to the higher new voltage in a controlled manner. The Negotiated new voltage (e.g., 5V, 9V, 15V, …) defines the nominal value for vSrcNew. During the positive transition the Source Should be able to supply the Sink Standby current and the transient current to charge the total bulk capacitance on VBUS. The slew rate of the positive transition Shall Not exceed vSrcSlewPos. The transitioning Source output voltage Shall settle within vSrcNew by tSrcSettle. The Source Shall be able to supply the Negotiated power level at the new voltage by tSrcReady. The positive voltage transition Shall remain above vSrcValid min of the previous Explicit Contract and below vSrcValid max of the new Explicit Contract (Figure 7.2, "Transition Envelope for Positive Voltage Transitions"). The voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.2, "Transition Envelope for Positive Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.2 Transition Envelope for Positive Voltage Transitions At the start of the positive voltage transition the VBUS voltage level Shall Not droop vSrcValid min below either vSrcNew (i.e., if the starting VBUS voltage level is not vSafe5V) or vSafe5V as applicable. Starting voltage vSrcNew(typ) t0 vSrcSlewPos tSrcSettle vSrcValid(max) Upper bound of valid Source range vSrcNew(max) vSrcNew(min) tSrcReady Lower bound of valid Source range § § vSrcValid(min) beyond min/max limits of starting voltage Page 314 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewPos limit. 7.1.4.1.2 Fixed Supply Negative Voltage Transitions Negative voltage transitions are defined as shown in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" and are specified in a similar manner to positive voltage transitions. Figure 7.3, "Transition Envelope for Negative Voltage Transitions" does not apply to vSafe0V transitions. The slew rate of the negative transition Shall Not exceed vSrcSlewNeg. The negative voltage transition Shall remain below vSrcValid max of the previous Explicit Contract and above vSrcValid min of the new Explicit Contract, as shown in FFigure 7.3, "Transition Envelope for Negative Voltage Transitions". The transitioning Source output voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.3 Transition Envelope for Negative Voltage Transitions If the newly Negotiated voltage is vSafe5V, then the vSrcValid limits Shall determine the transition window and the transitioning Source Shall settle within the vSafe5V limits by tSrcSettle. Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewNeg limit. 7.1.4.2 SPR Programmable Power Supply (PPS) 7.1.4.2.1 SPR Programmable Power Supply Voltage Transitions The Programmable Power Supply (PPS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the Programmable RDO defines the nominal value of the PPS output voltage after completing a voltage change and Shall settle within the limits defined by vPpsNew by tPpsSrcTransSmall for steps smaller than or equal to vPpsSmallStep, or else, within the limits defined by vPpsNew by tPpsSrcTransLarge, but only in case the Programmable Power Supply is not in CL mode. Any overshoot beyond vPpsNew Shall Not exceed vPpsValid at any time. Any undershoot beyond vPpsNew Shall Not exceed vPpsValid for currents not resulting in CL mode. The PPS output voltage May change in a step-wise or linear manner and the slew rate of either type of change Shall Not exceed vPpsSlewPos for voltage increases or vPpsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the PPS output voltage is defined as vPpsStep. A PPS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level. All PPS voltage increases Shall Starting voltage Lower bound of valid Source range Upper bound of valid Source range t0 tSrcSettle tSrcReady vSrcNew(typ) vSrcValid(min) vSrcNew(max) vSrcNew(min) § vSrcSlewNeg § vSrcValid(max) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 315 result in a voltage that is greater than or equal to the previous PPS output voltage. Likewise, all PPS voltage decreases Shall result in a voltage that is less than or equal to the previous PPS output voltage. Since a Sink can draw current up to the Negotiated APDO current level in case of a voltage step, the voltage might not increase to the requested level due to the power supply operating in CL mode. Likewise, since a Sink can have a Battery connected to VBUS, the voltage might not decrease to the requested level due to the Battery voltage being higher than the output voltage set point the Source is transitioning to. Were the Source to rely on checking the voltage on VBUS, in either case, to determine when its power supply is ready a PS_RDY Message would never be sent. When the PPS voltage steps up or down, a PS_RDY Message Shall be sent within:  tPpsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vPpsSmallStep.  tPpsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vPpsSmallStep provided that either the voltage on VBUS has reached vPpsNew or the power supply is in CL mode. When vPpsNew is lower than the Battery voltage, or the Source's primary power is cut off the Sink Shall immediately disconnect its Battery from VBUS. In these situations, the output current could reverse polarity and the Sink is not allowed to source current (see Section 7.2.1, "Behavioral Aspects" and Section 7.2.9, "Robust Sink Operation"). Figure 7.4, "PPS Positive Voltage Transitions" and Figure 7.5, "PPS Negative Voltage Transitions" below show the output voltage behavior of a Programmable Power Supply in response to positive and negative voltage change requests. The parameters vPpsMinVoltage and vPpsMaxVoltage define the lower and upper limits of the PPS range respectively (see Table 10.11, "SPR Programmable Power Supply Voltage Ranges" for required ranges). vPpsMinVoltage corresponds to the Minimum Voltage field in the PPS APDO and vPpsMaxVoltage corresponds to Maximum Voltage field in the PPS APDO. If the Sink negotiates for a new PPS APDO, then the transition between the two PPS APDOs Shall occur as described in Section 7.3.1, "Transitions caused by a Request Message". Figure 7.4 PPS Positive Voltage Transitions vPpsMinVoltage V(2) = 1 + vPpsMinVoltage vPpsMinVoltage V(1) § § Programmable Power Supply Output Range § vPpsSlewPos V(3) = 1+n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § vPpsSlewPos vPpsSlewPos § § § § vPpsValid vPpsNew § § vPpsValid vPpsValid vPpsNew § § vPpsValid Nominal V(2) Nominal V(3) vPpsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) Page 316 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.5 PPS Negative Voltage Transitions Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vPpsSlewNeg and vPpsSlewPos limits. See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage and current DNL step adjustments. 7.1.4.2.2 SPR Programmable Power Supply Current Limit The Programmable Power Supply operating in SPR PPS Mode Shall limit its output current to the Operating Current field value in the RDO when the Sink attempts to draw more current than the Operating Current field value level. The programming step size for the Operating Current is iPpsCLStep. All programming changes of the Operating Current Shall settle to the new Operating Current field value within tPpsCLProgramSettle. The SPR PPS Operating Current regulation accuracy during Current Limit is defined as iPpsCLNew. The minimum programmable Current Limit level is iPpsCLMin. A Source that supports SPR PPS Mode Shall support Current Limit programmability between iPpsCLMin and the Maximum Current value in the SPR PPS APDO. A Source which receives a request for current below iPpsCLMin Should reject the request. A Source that accepts a request for current below iPpsCLMin Shall set its current limit at 1A. The response of an SPR PPS to a load change depends on the Operating mode of the SPR PPS and the magnitude of the load change. These dependencies lead to one of four possible responses of an SPR PPS to any load change. They are differentiated by the value of the PPS Status OMF before and after the load change:  If the PPS Status OMF is cleared both before and after the load change, the SPR PPS responds solely by maintaining the output voltage. The SPR PPS output voltage Shall remain within vPpsValid range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsTransient. The Operating Mode Flag Shall remain cleared during the load change response of the SPR PPS.  If the PPS Status OMF is cleared before the load change and set after the load change, the SPR PPS responds by reducing its output voltage to limit the SPR PPS output current. The SPR PPS output current Shall stay within the iPpsCVCLTransient range once it reaches the iPpsCVCLTransient range. The SPR vPpsMinVoltage V(c) = 1 + vPpsMinVoltage vPpsMinVoltage V(d) § § Programmable Power Supply Output Range § V(b) = 1 + n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § § § § vPpsValid vPpsNew § § vPpsValid Nominal V(c) Nominal V(b) vPpsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vPpsValid vPpsNew § § vPpsValid § vPpsSlewNeg vPpsSlewNeg vPpsSlewNeg Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 317 PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCVCLTransient. The Operating Mode Flag Shall be set when the SPR PPS load change response settles.  If the PPS Status OMF is set both before and after the load change, the SPR PPS responds by adjusting its output voltage to maintain the output current. The SPR PPS output current Shall stay within the iPpsCLTransient range. The SPR PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCLSettle. The Operating Mode Flag Shall remain set during the load change response of the SPR PPS.  If the PPS Status OMF is set before the load change and cleared after the load change, the PPS responds to the load change by increasing its output voltage to vPpsNew and then maintaining it. The SPR PPS output voltage Shall stay within the vPpsCLCVTransient range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsCLCVTransient. The Operating Mode Flag Shall be cleared when the PPS load change response settles. The SPR PPS Source Shall maintain its output voltage at the value requested in the PPS RDO for all static and dynamic load conditions except when in Current Limit operation. In response to any static or dynamic load condition during Current Limit operation that causes the SPR PPS output voltage to drop below vPpsShutdown the Source May send Hard Reset Signaling and Shall discharge VBUS to vSafe0V then resumes USB Default Operation at vSafe5V. When the Sink attempts to draw more current than the Operating Current in the RDO, the Source Shall limit its output current. The current available from the Source during Current Limit mode Shall meet iPpsCLNew. The Sink May Not reduce its Operating Current request in the RDO when the PPS Status OMF is set. Current limiting Shall be performed by the SPR PPS Source. Sinks that rely on PPS Current Limiting Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The Source Shall Not shutdown or otherwise disrupt the available output power while in Current Limit mode unless another protection mechanism as outlined in Section 7.1.7, "Robust Source Operation" is engaged to protect the Source from damage. An SPR PPS Source that is operating in Current Limit Shall Not change its set-point in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The relationship between SPR PPS programmable output voltage and SPR PPS programmable Current Limit Shall be as shown in Figure 7.6, "SPR PPS Programmable Voltage and Current Limit". The transition between the Constant Voltage mode and the Current Limit mode occurs between points a and b. The PPS Status OMF Shall be set or cleared within this region. In Current Limit mode when the load resistance changes, the output current of the Source Shall stay within iPpsCLNew. The proper behavior is represented by point c. Page 318 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.6 SPR PPS Programmable Voltage and Current Limit 7.1.4.2.3 SPR PPS Constant Power Mode In Constant Power mode (when the PPS Power Limited bit is set) the Source May supply power that exceeds the Source's PDP Rating. Sinks May limit their Operating Current request in the RDO and Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The tolerances along the Constant Power Curve Shall Not extend into the Guaranteed Capability Area of Figure 7.7, "SPR PPS Constant Power". Current Voltage PPS APDO Min Voltage (max) PPS APDO Max Voltage iPpsCLMin PPS APDO Max Current vPpsNew PPS RDO Operating Current PPS RDO Output Voltage Programmable Voltage Only Region Programmable Voltage & Programmable Current Limit Region Valid Current Limit Response Invalid Current Limit Response iPpsCLNew a Current Limit Flag set Current Limit Flag cleared b c c c Source Disconnect Region vPpsShutdown (min) Point a represents entry into the transition region between Constant Voltage mode and Current Limit mode. Point b represents exit from the transition region between Constant Voltage mode and Current Limit mode. Point c represents the exit from the iPpsCLNew region as the voltage drops below the PPS APDO Min Voltage. The Source May disconnect at any point inside the tolerance range of the minimum voltage defined in the PPS APDO. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 319 Figure 7.7 SPR PPS Constant Power Current Voltage Nominal limits as pr. the APDO Guaranteed operating capability as pr. the APDO Tolerance area for actual voltages (only static tolerances are shown) vPpsNew PDP constant power curve Max APDO Voltage Capabilities when the Power Limited bit is set The figure shows only the steady state after the transition vPpsNew 0A 0V iPpsCLNew (X = PPS APDO Max Current, Y = Prog Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • Prog Voltage = 9V • PPS APDO Max Current = 3 A Coordinate = (3, 9) vPpsNew Min APDO Voltage vPpsNew iPpsCLMin(1A) Min Current Limit PPS APDO Max Current Valid Current Limit Range (X = PDP/PPS APDO Max Current, Y = PPS APDO Max Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • PPS APDO Max Voltage = 11 V Coordinate = (2.45, 11) Page 320 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3 Adjustable Voltage Supply (AVS) 7.1.4.3.1 Adjustable Voltage Supply Voltage Transitions The Adjustable Voltage Supply (AVS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the AVS RDO defines the nominal value of the AVS output voltage after completing a voltage change and Shall settle within the limits defined by vAvsNew by tAvsSrcTransSmall for steps smaller than or equal to vAvsSmallStep, or else, within the limits defined by vAvsNew by tAvsSrcTransLarge for steps larger than vAvsSmallStep. Any overshoot beyond vAvsNew Shall Not exceed vAvsValid at any time. Any undershoot beyond vAvsNew Shall Not exceed vAvsValid at any time. The AVS output voltage May change in a stepwise or linear manner and the slew rate of either type of change Shall Not exceed vAvsSlewPos for voltage increases or vAvsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the AVS output voltage is defined as vAvsStep. An AVS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level if the change of output voltage is less than or equal to vAvsSmallStep relative to vAvsNew. All AVS voltage increases Shall result in a voltage that is greater than or equal to the previous AVS output voltage. Likewise, all AVS voltage decreases Shall result in a voltage that is less than or equal to the previous AVS output voltage. Any time the Source enters the AVS range of operation that voltage transition is considered a voltage step larger than vAvsSmallStep. When the AVS voltage steps up or down, a PS_RDY Message Shall be sent within:  tAvsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vAvsSmallStep.  tAvsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vAvsSmallStep provided the voltage on VBUS has reached vAvsNew. Figure 7.8, "AVS Positive Voltage Transitions" and Figure 7.9, "AVS Negative Voltage Transitions" below show the output voltage behavior of an AVS in response to positive and negative voltage change requests. The parameters vAvsMinVoltage and vAvsMaxVoltage define the lower and upper limits of the AVS range respectively:  For SPR AVS Sources there are two possible voltage ranges where the vAvsMinVoltage is always 9V and vAvsMaxVoltage is either 15V or 20V depending on the Source's PDP. See Table 10.9, "SPR Adjustable Voltage Supply (AVS) Voltage Ranges".  For EPR AVS Sources vAvsMinVoltage corresponds to Minimum Voltage field (always 15V) in the EPR AVS APDO and vAvsMaxVoltage corresponds to Maximum Voltage field in the EPR AVS APDO. See Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" for required ranges. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 321 Figure 7.8 AVS Positive Voltage Transitions Figure 7.9 AVS Negative Voltage Transitions See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage DNL step adjustments. vAvsMinVoltage V(2) = 1 + vAvsMinVoltage vAvsMinVoltage V(1) § § Adjustable Voltage Supply Output Range § vAvsSlewPos V(3) = 1+n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § vAvsSlewPos vAvsSlewPos § § § § vAvsValid vAvsNew § § vAvsValid vAvsValid vAvsNew § § vAvsValid Nominal V(2) Nominal V(3) vAvsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) vAvsMinVoltage V(c) = 1 + vAvsMinVoltage vAvsMinVoltage V(d) § § Adjustable Voltage Supply Output Range § V(b) = 1 + n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § § § § vAvsValid vAvsNew § § vAvsValid Nominal V(c) Nominal V(b) vAvsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vAvsValid vAvsNew § § vAvsValid § vAvsSlewNeg vAvsSlewNeg vAvsSlewNeg Page 322 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3.2 Adjustable Voltage Supply Current The AVS Shall maintain its output voltage at the value requested in the AVS RDO for all static and dynamic load conditions that do not exceed the Operating Current in the RDO. Unlike the SPR PPS programmable current, the AVS programmable power May range from zero to the PDP. The maximum operating current:  For SPR Sources, the maximum operating current is defined in the SPR Source_Capabilities Message Maximum Current 15V/Maximum Current 20V fields.  For EPR Sources, the maximum operating current has to be calculated as the lower of the PDP field value/Output Voltage or 5A whichever is lower. See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" 7.1.5 Response to Hard Resets Hard Reset Signaling indicates a communication failure has occurred and the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall drive VBUS to vSafe0V as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". The USB connection May reset during a Hard Reset since the VBUS voltage will be less than vSafe5V for an extended period of time. After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform to the VCONN timing as specified in [USB Type-C 2.4]. A Sink that enters Hard Reset can have cSnkBulkPd present until VBUS drops below vSafe0V. The Source Shall take this into consideration. Device operation during and after a Hard Reset is defined as follows:  Self-powered devices Should Not disconnect from USB during a Hard Reset (see Section 9.1.2, "Mapping to USB Device States").  Self-powered devices operating at more than vSafe5V May Not maintain full functionality after a Hard Reset.  Bus powered devices will disconnect from USB during a Hard Reset due to the loss of their power source. When a Hard Reset occurs the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall start to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. The Source Shall meet both tSafe5V and tSafe0V relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 323 Figure 7.10 Source VBUS and VCONN Response to Hard Reset VCONN will meet tVCONNDischarge relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset" due to the discharge circuitry in the Cable Plug. VCONN Shall meet tVCONNOn relative to VBUS reaching vSafe5V. Note: tVCONNOn and tVCONNDischarge are defined in [USB Type-C 2.4]. 7.1.6 Changing the Output Power Capability Some USB Power Delivery Negotiations will require the Source to adjust its output power capability without changing the output voltage. In this case the Source Shall be able to supply a higher or lower load current within tSrcReady. 7.1.7 Robust Source Operation 7.1.7.1 Output Over Current Protection Sources Shall implement over current protection to prevent damage from output current that exceeds the current handling capability of the Source. The definition of current handling capability is left to the discretion of the Source implementation and Shall take into consideration the current handling capability of the connector contacts. If the over current protection implementation does not use a Hard Reset or Error Recovery, it Shall Not interfere with the Negotiated VBUS current level. After three consecutive over current events Source Shall go to ErrorRecovery. Sources Should attempt to send Hard Reset Signaling when over current protection engages followed by an Alert Message indicating an OCP event once an Explicit Contract has been established. The over current protection response May engage at either the Port or system level. Systems or ports that have engaged over current protection Should attempt to resume USB Default Operation after determining that the cause of over current is no longer present and May latch off to protect the Port or system. The definition of how to detect if the cause of over current is still present is left to the discretion of the Source implementation. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over current event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over current protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over current. During the over current response and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. Old voltage 0V vSafe0V(max) vSrcNeg(max) t0 tSafe5V tSafe0V tSrcTurnOn vSafe5V(max), VCONN(max) § vVconnDischarge tVconnDischarge tVconnOn tSrcRecover Page 324 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.7.2 Over Temperature Protection Sources Shall implement Over Temperature Protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Source. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Source implementation. In order to avoid reaching an OTP event, Sources May proactively reduce the available power being offered to the Sink, even though these offers might be lower than the Source would be expected to offer during normal thermal operating conditions. Prior to reducing power, the Source Should generate Alert Message indicating an Operating Condition Change and set the Temperature Status bit in the SOP Status Message to Warning (10b). Sources Should attempt to send Hard Reset Signaling when OTP engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The OTP response May engage at either the Port or system level. Systems or ports that have engaged OTP Should attempt to resume USB Default Operation and May latch off to protect the Port or system. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over temperature event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. During the OTP and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. 7.1.7.3 vSafe5V Externally Applied to Ports Supplying vSafe5V Safe operation mandates that Power Delivery Sources Shall be tolerant of vSafe5V being present on VBUS when simultaneously applying power to VBUS. Normal USB PD communication Shall be supported when this vSafe5V to vSafe5V connection exists. 7.1.7.4 Detach A USB Detach is detected electrically using CC detection on the USB Type-C connector. When the Source is Detached the Source Shall transition to vSafe0V by tSafe0V relative to when the Detach event occurred. During the transition to vSafe0V the VBUS voltage Shall be below vSafe5V max by tSafe5V relative to when the Detach event occurred and Shall Not exceed vSafe5V max after this time. Sources operating in EPR Mode need to avoid creating large differential voltages at the connector. See Appendix H in the [USB Type-C 2.4] specification for background information. To achieve this, Sources operating in EPR Mode, upon detecting a disconnect, Shall stop sourcing current and minimize VBUS capacitance. There May continue to be current sourced from the Source bulk capacitance, but that Should also be minimized by disconnecting as much of the Source bulk capacitance as possible. For example, the Source can stop sourcing from the Power Supply and the C1 portion of the Source bulk capacitance in Figure 7.1, "Placement of Source Bulk Capacitance" by disabling the Ohmic Interconnect switch. The Source Should detect the disconnect, stop sourcing current, and minimize the VBUS capacitance as quickly as practical. If this is done after the CC contacts disconnect and before the VBUS contacts disconnect there is less risk of large differential voltages at the connector. Note: A USB-PD transmission by the Source during a disconnect event will delay disconnect detection by the Source. 7.1.7.5 Output Voltage Limit The output voltage of Sources Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid or vAvsNew, vAvsValid as determined by the Negotiated VBUS value. Sources Shall meet applicable safety and regulatory requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 325 7.1.8 Output Voltage Tolerance and Range After a voltage transition is complete (i.e., after tSrcReady) and during static load conditions the Source output voltage Shall remain within the vSrcNew or vSafe5V limits as applicable. The ranges defined by vSrcNew and vSafe5V account for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e., after tSrcReady) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vSrcValid. The amount of time the Source output voltage can be in the band between either vSrcNew or vSafe5V and vSrcValid Shall Not exceed tSrcTransient. Refer to Table 7.23, "Source Electrical Parameters" for the output voltage tolerance specifications. Figure 7.11, "Application of vSrcNew and vSrcValid limits after tSrcReady" illustrates the application of vSrcNew and vSrcValid after the voltage transition is complete. The vSrcNew and vSrcValid limits Shall Not apply to VBUS during the VBUS discharge and switchover that occurs during a Fast Role Swap as described in Section 7.1.13, "Fast Role Swap". Figure 7.11 Application of vSrcNew and vSrcValid limits after tSrcReady The Source output voltage Shall be measured at the connector receptacle. The stability of the Source Shall be tested in 25% load step increments from minimum load to maximum load and also from maximum load to minimum load. The transient behavior of the load current is defined in Section 7.2.6, "Transient Load Behavior". The time between each step Shall be sufficient to allow for the output voltage to settle between load steps. In some systems it might be necessary to design the Source to compensate for the voltage drop between the output stage of the power supply electronics and the receptacle contact. The determination of whether compensation is necessary is left to the discretion of the Source implementation. 7.1.8.1 AVS/PPS Output Voltage Ripple The AVS/PPS output voltage ripple is expected to exceed the magnitude of one or more LSB as show in the Figure 7.12, "Expected AVS/PPS Ripple Relative to an LSB". Sink Load I1 vSrcNew(typ) tSrcReady iLoadStepRate vSrcValid(max) vSrcValid(min) vSrcNew(max) vSrcNew(min) tSrcTransient window у tSrcTransient windows у у iLoadReleaseRate Sink Load I2 Page 326 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.12 Expected AVS/PPS Ripple Relative to an LSB 7.1.8.2 AVS/PPS DNL Errors and Output Voltage/Current Tolerance The PPS voltage and current discrete LSB steps have a DNL tolerance as shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode" below. In absolute terms the step size of the LSB for both voltage and current is defined by vPpsStep/vAvsStep for voltage and iPpsCLStep for current. Several examples of Valid LSB steps are shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode":  The upper end of the DNL error (+1 LSB) shows the case where one step is effectively skipped.  The lower end of the DNL error (-1 LSB) shows the case where the voltage or current set-point remained the same. The ideal scenario for the DNL error (=0) matches the typical step size for the voltage or current. The intent of DNL is to guarantee that changes to the voltage/current have the correct directionality, and that the maximum step size is clearly defined. Note: The Source Should avoid scenarios where multiple consecutive steps have errors close to the Maximum and Minimum DNL. time voltage +1 LSB +1 LSB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 327 Figure 7.13 Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode 7.1.8.3 Programmable Power Supply Output Voltage Tolerance and Range After a voltage transition of a Programmable Power Supply is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vPpsNew limits. The range defined by vPpsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vPpsValid. The amount of time the Source output voltage can be in the band between vPpsNew and vPpsValid Shall Not exceed tPpsTransient. 7.1.8.4 Adjustable Voltage Supply Output Voltage tolerance and Range After a voltage transition of an AVS is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vAvsNew limits. The range defined by vAvsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vAvsValid. The amount of time the Source output voltage can be in the band between vAvsNew and vAvsValid Shall Not exceed tAvsTransient. Code Voltage, Current 1 LSB DNL < 0 LSB Max DNL = 1 LSB vPpsNew,vAvsNew, iPpsNew (max) vPpsNew,vAvsNew, iPpsNew (min) vPpsNew,vAvsNew, iPpsNew DNL = -1 LSB Page 328 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.9 Charging and Discharging the Bulk Capacitance on VBUS The Source Shall charge and discharge the bulk capacitance on VBUS whenever the Source voltage is Negotiated to a different value. The charging or discharging occurs during the voltage transition and Shall Not interfere with the Source's ability to meet tSrcReady. 7.1.10 Swap Standby for Sources Sources and Sinks of a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Source after the Source power supply has discharged the bulk capacitance on VBUS to vSafe0V as part of the Power Role Swap transition. While in Swap Standby:  The Source Shall Not drive VBUS that is therefore expected to remain at vSafe0V.  Any discharge circuitry that was used to achieve vSafe0V Shall be removed from VBUS.  The Dual-Role Power Port Shall be configured as a Sink.  The USB connection Shall Not reset even though vSafe5V is no longer present on VBUS (see Section 9.1.2, "Mapping to USB Device States"). The PS_RDY Message associated with the Source being in Swap Standby Shall be sent after the VBUS drive is removed. The time for the Source to transition to Swap Standby Shall Not exceed tSrcSwapStdby. Upon entering Swap Standby, the Source has relinquished its Power Role as Source and is ready to become the New Sink. The transition time from Swap Standby to being the New Sink Shall be no more than tNewSnk. The New Sink May start using power after the new Source sends the PS_RDY Message. 7.1.11 Source Peak Current Operation A Source that has the Fixed Supply PDO or AVS APDO Peak Current bits set to 01b, 10b and 11b Shall be designed to support one of the overload Capabilities defined in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability" respectively. The overload conditions are bound in magnitude, duration and duty cycle as listed in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability". Sources are not required to support continuous overload operation. When overload conditions occur, the Source is allowed the range of vSrcPeak (instead of vSrcNew) relative to the nominal value (see Figure 7.14, "Source Peak Current Overload"). When the overload capability is exceeded, the Source is expected take whatever action is necessary to prevent electrical or thermal damage to the Source. The Source May send a new Source_Capabilities Message with the Fixed Supply PDO or AVS APDO Peak Current bits set to 00b to prohibit overload operation even if an overload capability was previously Negotiated with the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 329 Figure 7.14 Source Peak Current Overload 7.1.12 Source Capabilities Extended Parameters Implementers can choose to make available certain characteristics of a PDUSB Source as a set of Static and/or dynamic parameters to improve interoperability between external power sources and portable computing devices. The complete list of reportable Static parameters is described in full in Section 6.5.1, "Source_Capabilities_Extended Message" and listed in Figure 6.37, "Source_Capabilities_Extended Message". The subset of parameters listed below directly represent Source Capabilities and are described in the rest of this section.  Voltage Regulation.  Holdup Time.  Compliance.  Peak Current.  Source Inputs.  Batteries. 7.1.12.1 Voltage Regulation Field The power consumption of a device can change dynamically. The ability of the Source to regulate its voltage output might be important if the device is sensitive to fluctuations in voltage. The Voltage Regulation bit field is used to convey information about the Sources output regulation and tolerance to various load steps. 7.1.12.1.1 Load Step Slew Rate The default load step slew rate is established at 150mA/µs. A Source Shall meet the following requirements under the load step reported in the Source_Capabilities_Extended Message:  The Source Shall maintain VBUS regulation within the vSrcValid range.  The noise on the CC line Shall remain below vNoiseIdle and vNoiseActive. Sink Port Current Source Port Voltage vSrcNew(max)/ vSrcPeak(max) Nominal Voltage vSrcNew(min) vSrcPeak(min) IOC level as requested in the Operating Current field of an RDO % level with respect to IOC as advertised in the Peak Current field of Fixed Supply PDO Additional operating range for Fixed Supply that supports overload capability Operating range for supply that DOES NOT support overload capability Page 330 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Test conditions require a change in both positive and negative load steps from 1Hz to 5000Hz, up to the Advertised Load Step Magnitude of the full load output including from both 10 mA and 10% initial load. The Source Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks" under all load conditions. 7.1.12.1.2 Load Step Magnitude The default load step magnitude rate Shall be 25% of IoC. The Source May report higher capability tolerating a load step of 90% of IoC. 7.1.12.2 Holdup Time Field The Holdup Time field Shall return a numeric value of the number of milliseconds the output voltage stays in regulation upon a short interruption of the AC Supply. An AC Supplied Source Shall report its holdup time in this field. The holdup time is measured with the load at rated maximum, with the AC Supply at 115VAC rms and 60Hz (or at 230VAC rms and 50Hz for a Source that does not support 115VAC AC Supply). The reported time describes the minimum length of time from the last completed AC Supply input cycle (zero-degree phase angle) until when the output voltage decays below vSrcValid (min). Sources are recommended to support a minimum of 3ms and are preferred to support over 10 milliseconds holdup time (equivalent to a half cycle drop from the AC Supply). See Figure 7.15, "Holdup Time Measurement". Figure 7.15 Holdup Time Measurement 7.1.12.3 Compliance Field An SPR Source claiming LPS, PS1 or PS2 compliance (see [IEC 62368-1]) Shall report its Capabilities in the Compliance field. Since the SPR Source May have several potential output voltage and current settings, every SPR Source supply (each indicated by a PDO) Shall be compliant to LPS requirements. Note: According to the requirements of [IEC 60950-1] and/or [IEC 62368-3], a device tested and certified with an LPS Source (SPR Source or EPR Source operating in SPR Mode) is prohibited from using a non-LPS Source (EPR Source operating in EPR Mode). Alternatively, [IEC 62368-1], classifies power sources according to their maximum, constrained power output (15watts or 100watts). 7.1.12.4 Peak Current The Source reports its ability to source peak current delivery in excess of the Negotiated amount in the Peak Current field. The duration of peak current Shall be followed by a current consumption below the Operating Current (IoC) in order to maintain average power delivery below the IoC current. vSrcValid(min) Hold Up Time у VBUS AC mains voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 331 A Source May have greater capability to source peak current than can be reported using the Peak Current field in the Fixed Supply PDO or AVS APDO. In this case the Source Shall report its additional capability in the Peak Current1/Peak Current2/Peak Current3 fields in the Source_Capabilities_Extended Message. Each overload period Shall be followed by a period of reduced current draw such that the rolling average current over the Overload Period field value with the specified Duty Cycle field value (see Section 6.5.1.10, "Peak Current Field") Shall Not exceed the Negotiated current. This is calculated as: Period of reduced current = (1 - value in Duty Cycle field/100) * value in Overload Period field 7.1.12.5 Source Inputs The Source Inputs field identifies the possible inputs that provide power to the Source. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. 7.1.12.6 Batteries The Number of Batteries/Battery Slots field Shall report the number of Batteries the Source supports. The Source Shall independently report the number of Hot Swappable Batteries and the number of Fixed Batteries. 7.1.13 Fast Role Swap A Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port supporting DRP as shown in Figure 7.16, "VBUS Power during Fast Role Swap". Figure 7.16 VBUS Power during Fast Role Swap When the power source connected to the Hub UFP stops sourcing power and VBUS at the Hub DRP connector discharges below vSrcValid(min), if VBUS has been Negotiated to a higher voltage than vSafe5V, or vSafe5V (min) the Fast Role Swap Request Shall be sent from the Hub DRP to the Host DRP and the Hub DRP Shall sink power. In the Fast Role Swap use case, the Hub DRP behaves like a bidirectional power path. The Hub DRP Shall Not enable VBUS discharge circuitry when changing operation from Initial Source to New Sink. The Hub DFP Port(s) Shall support default USB Type-C Current (see [USB Type-C 2.4]) until a new Explicit Contract is Negotiated. After sending the Fast Role Swap Request and while VBUS > vSafe5V (min), the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. The New Sink Shall Not draw more than iSnkStdby from VBUS until tSnkFRSwap after it has started sending the Fast Role Swap Request or VBUS has fallen below vSafe5V (min). The tSnkFRSwap time Shall start at the beginning of the Fast Role Swap Request or when VBUS falls below vSafe5V (min), whichever comes later. After waiting for tSnkFRSwap, the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. After the New Source has applied its Rp, the New Sink Shall be limited to USB Type-C Current (see [USB Type-C 2.4]) in an Implicit Contract until a new Explicit Contract is Negotiated. All Sink requirements Shall apply to the New Sink after the Fast Role Swap is complete. The Fast Role Swap response of the Host DRP is described in Section 7.2.10, "Fast Role Swap" since the Host DRP is operating as the Initial Sink prior to the Fast Role Swap. After the VBUS voltage level at the Hub DRP connector drops below vSafe5V a PS_RDY Message Shall be sent to the Host DRP as shown in the Fast Role Swap transition diagram of Section 7.3.4, "Transitions Caused by Fast Role Swap". USB PD Capable Hub DRP UFP DFP Power Source Bus Powered Accessory USB PD Capable Host DRP Power flow before the Fast Role Swap Power flow after the Fast Role Swap Page 332 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.17, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min)" and Figure 7.18, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min)" show the VBUS detection and timing for the New Source during a Fast Role Swap after the Fast Role Swap Request has been received. The New Source May turn on the VBUS output switch once VBUS is below vSafe5V (max). In this case, the New Source prevents VBUS from falling below vSafe5V (min). The new source Shall turn on the VBUS output switch within tSrcFRSwap of falling below vSafe5V (min). VBUS might have started at vSafe5V or at higher voltage. When the Fast Role Swap Request is detected, VBUS could therefore be either above vSafe5V (max), within the vSafe5V range, or below vSafe5V (min). If the Fast Role Swap Request is detected when VBUS is below vSafe5V (min), then the new source Shall turn on the VBUS output switch within tSrcFRSwap of detecting the Fast Role Swap Request. In this case, the maximum time from the beginning of the Fast Role Swap Request to VBUS being sourced May be tSrcFRSwap (max) + tFRSwapRx (max). Figure 7.17 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min) Figure 7.18 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min) 7.1.14 Non-application of VBUS Slew Rate Limits Scenarios where vSrcSlewPos and vPpsSlewPos VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When first applying VBUS after an Attach.  When applying VBUS as part of a Power Role Swap to Source Power Role.  When increasing VBUS from vSafe0V to vSafe5V during a Hard Reset.  During a Fast Role Swap when the Initial Sink applies VBUS. Old Voltage 0V vSafe5V(min) tSrcFRSwap vSafe5V(max) § New Source may turn on at any time after VBUS falls below vSafe5V(max) VBUS Old Source detects power loss and signals Fast Role Swap Old Voltage 0V vSafe5V(min) tSrcFRSwap VBUS is below vSafe5V(min) before FRS signal is finished Old Source detects power loss and signals Fast Role Swap tFRSwapRx (max) VBUS at new Source CC New Source may turn on after detecting Fast Role Swap signal Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 333 Scenarios where vSrcSlewNeg and vPpsSlewNeg VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When discharging VBUS to vSafe0V during a Hard Reset.  When discharging VBUS to vSafe0V as part of a Power Role Swap to Sink Power Role.  When discharging VBUS to vSafe0V after a Detach.  During a Fast Role Swap when the VBUS power source connected to the Hub UFP stops sourcing power. 7.1.15 VCONN Power Cycle 7.1.15.1 UFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the UFP is the VCONN Source, the following steps Shall be followed:  Following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message, the UFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type- C 2.4]) within tVCONNZero.  When VCONN is below vRaReconnect, the UFP Shall send a PS_RDY Message. Note: If the UFP was not sourcing VCONN, it still sends the PS_RDY Message.  The DFP Shall wait tVCONNReapplied following the last bit of the GoodCRC Message acknowledging the PS_RDY Message before sourcing VCONN. The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.19, "Data Reset UFP VCONN Power Cycle" below illustrates the UFP VCONN Power Cycle process. Figure 7.19 Data Reset UFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied PS_RDY (UFP) UFP DFP Page 334 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.15.2 DFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the DFP is the VCONN Source, the following steps Shall be followed: 1) If the DFP sent the Data_Reset Message and is sourcing VCONN then it Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero of the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 2) If the UFP sent the Data_Reset Message then the DFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 3) When VCONN is below vRaReconnect, the DFP Shall wait tVCONNReapplied before sourcing VCONN. 4) The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.20, "Data Reset DFP VCONN Power Cycle" below illustrates the DFP VCONN Power Cycle process. Figure 7.20 Data Reset DFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied UFP DFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 335 7.2 Sink Requirements 7.2.1 Behavioral Aspects A PDUSB Sink exhibits the following behaviors:  Shall Not draw more than [USB Type-C 2.4] USB Type-C Current from VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS in-rush current when increasing current consumption according to [USB 2.0] or [USB 3.2] as appropriate. 7.2.2 Sink Bulk Capacitance The Sink bulk capacitance consists of C3 and C4 as shown in Figure 7.21, "Placement of Sink Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect is expected to be part of an input Over Voltage Protection (Sink OVP) circuit implemented by the Sink as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. A Sink Shall implement OVP. The Sink Shall Not rely on the Source output voltage limit for its input OVP. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. An upper bound of cSnkBulkPd Shall Not be exceeded so that the transient charging, or discharging, of the total bulk capacitance on VBUS can be accounted for during voltage transitions. The Sink bulk capacitance that is within the cSnkBulk max or cSnkBulkPd max limits is allowed to change to support a newly Negotiated power level. The capacitance can be changed when the Sink enters Sink Standby or during a voltage transition or when the Sink begins to operate at the new power level. Changing the Sink bulk capacitance Shall Not cause a transient current on VBUS that violates the present Contract. During a Power Role Swap the Default Sink Shall transition to Swap Standby before operating as the New Source. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.21 Placement of Sink Bulk Capacitance 7.2.3 Sink Standby The Sink Shall transition to Sink Standby before a positive voltage transition of VBUS. During Sink Standby the Sink Shall reduce the current drawn to iSnkStdby. This allows the Source to manage the voltage transition as well as supply sufficient operating current to the Sink to maintain PD operation during the transition. The Sink Shall complete this transition to Sink Standby within tSnkStdby after evaluating the Accept Message from the Source. The transition when returning to Sink operation from Sink Standby Shall be completed within tSnkNewPower. The iSnkStdby requirement Shall only apply if the Sink current draw is higher than this level. See Section 7.3, "Transitions" for details. GND SHIELD VBUS ... Data Lines C3 GND SHIELD VBUS ... Data Lines SINK CABLE C4 Load Sink Bulk Capacitance Ohmic Interconnect OVP Page 336 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.3.1 Programmable Power Supply Sink Standby A Sink is not required to transition to Sink Standby when operating within the Negotiated PPS APDO. A Sink May consume the Operating Current value in the PPS RDO during PPS output voltage changes. However, prior to operating the SPR PPS in Current Limit, the Sink Shall program the PPS Operating Voltage to the lowest practical level that satisfies the Sink load requirement. Doing so will minimize the inrush current that occurs when the transition to Current Limit occurs. When operating with an SPR PPS Source that is in Current Limit, the Sink Shall Not change its load in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The load change magnitude Shall Not request a change to the Current Limit set-point that exceeds iPpsCLLoadStep. If the Sink Negotiates for a new PPS APDO, that is expected to increase VBUS voltage, then the Sink Shall transition to Sink Standby while changing between PPS APDOs as described in Section 7.3.1, "Transitions caused by a Request Message". 7.2.4 Suspend Power Consumption When Source has set its USB Suspend Supported flag (see Section 6.4.1.2.1.2, "USB Suspend Supported"), a Sink Shall go to the lowest power state during USB suspend. The lowest power state Shall be pSnkSusp or lower for a PDUSB Peripheral and pHubSusp or lower for a PDUSB Hub. There is no requirement for the Source voltage to be changed during USB suspend. 7.2.5 Zero Negotiated Current When a Sink Requests zero current as part of a power Negotiation with a Source, the Sink Shall go to the lowest power state, pSnkSusp or lower, where it can still communicate using PD signaling. 7.2.6 Transient Load Behavior When a Sink's operating current changes due to a load step, load release or any other change in load level, the positive or negative overshoot of the new load current Shall Not exceed the range defined by iOvershoot. For the purposes of measuring iOvershoot the new load current value is defined as the average steady state value of the load current after the load step has settled. The rate of change of any shift in Sink load current during normal operation Shall Not exceed iLoadStepRate (for load steps) and iLoadReleaseRate (for load releases) as measured at the Sink receptacle. The Sink's operating current Shall Not change faster than the value reported in the Source's Load Step Slew Rate in its Voltage Regulation bit field and Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks". 7.2.7 Swap Standby for Sinks The Sink functionality in a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Sink after evaluating the Accept Message from the Source during a Power Role Swap. While in Swap Standby the Sink's current draw Shall Not exceed iSnkSwapStdby from VBUS and the Dual-Role Power Port Shall be configured as a Source after VBUS has been discharged to vSafe0V by the existing Initial Source. The Sink's USB connection Should Not be reset even though vSafe5V is not present on the VBUS conductor (see Section 9.1.2, "Mapping to USB Device States"). The time for the Sink to transition to Swap Standby Shall be no more than tSnkSwapStdby. When in Swap Standby the Sink has relinquished its Power Role as Sink and will prepare to become the New Source. The transition time from Swap Standby to New Source Shall be no more than tNewSrc. 7.2.8 Sink Peak Current Operation Sinks Shall only make use of a Source overload capability when the corresponding Fixed Supply PDO Peak Current (see Section 6.4.1.2.1.8, "Peak Current") or AVS APDO Peak Current (see Section 6.4.1.2.4.3.2, "Peak Current") bits are set to 01b, 10b and 11b. Sinks Shall manage thermal aspects of the overload event by not exceeding the average Negotiated output of a Fixed Supply or AVS that supports Peak Current operation. Sinks that depend on the Peak Current capability for enhanced system performance Shall also function correctly when Attached to a Source that does not offer the Peak Current capability or when the Peak Current capability has been inhibited by the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 337 7.2.9 Robust Sink Operation 7.2.9.1 Sink Bulk Capacitance Discharge at Detach When a Source is Detached from a Sink, the Sink Shall continue to draw power from its input bulk capacitance until VBUS is discharged to vSafe5V or lower by no longer than tSafe5V from the Detach event. This safe Sink requirement Shall apply to all Sinks operating with a Negotiated VBUS level greater than vSafe5V and Shall apply during all low power and high-power operating modes of the Sink. If the Detach is detected during a Sink low power state, such as USB Suspend, the Sink can then draw as much power as needed from its bulk capacitance since a Source is no longer Attached. In order to achieve a successful Detach detect based on VBUS voltage level droop, the Sink power consumption Shall be high enough so that VBUS will decay below vSrcValid(min) well within tSafe5V after the Source bulk capacitance is removed due to the Detach. Once adequate VBUS droop has been achieved, a discharge circuit can be enabled to meet the safe Sink requirement. To illustrate the point, the following set of Sink conditions will not meet the safe Sink requirement without additional discharge circuitry:  Negotiated VBUS = 20V.  Maximum allowable supplied VBUS voltage = 21.55V.  Maximum bulk capacitance = 30µF.  Power consumption at Detach = 12.5mW. When the Detach occurs (hence removal of the Source bulk capacitance) the 12.5mW power consumption will draw down the VBUS voltage from the worst-case maximum level of 21.55V to 17V in approximately 205ms. At this point, with VBUS well below vSrcValid (min) an approximate 100mW discharge circuit can be enabled to increase the rate of Sink bulk capacitance discharge and meet the safe Sink requirement. The power level of the discharge circuit is dependent on how much time is left to discharge the remaining voltage on the Sink bulk capacitance. If a Sink has the ability to detect the Detach in a different manner and in much less time than tSafe5V, then this different manner of detection can be used to enable a discharge circuit, allowing even lower power dissipation during low power modes such as USB Suspend. In most applications, the safe Sink requirement will limit the maximum Sink bulk capacitance well below the cSnkBulkPd limit. A Detach occurring during Sink high power operating modes must quickly discharge the Sink bulk capacitance to vSafe5V or lower as long as the Sink continues to draw adequate power until VBUS has decayed to vSafe5V or lower. 7.2.9.2 Input Over Voltage Protection Sinks Shall implement input Over-Voltage Protection (OVP) to prevent damage from input voltage that exceeds the voltage handling capability of the Sink. The definition of voltage handling capability is left to the discretion of the Sink implementation. The over voltage response of Sinks Shall Not interfere with normal PD operation and Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid as determined by the Negotiated VBUS value. SPR Sinks Should tolerate input voltages as high as vSprMax and Shall meet applicable safety requirements if vSprMax is exceeded. Likewise, EPR Sinks Should tolerate input voltages as high as vEprMax and Shall meet applicable safety requirements if vEprMax is exceeded. Sinks Should attempt to send Hard Reset Signaling when OVP engages followed by an Alert Message indicating an OVP event once an Explicit Contract has been established. The OVP response May engage at either the Port or system level. Systems or ports that have engaged OVP Shall resume USB Default Operation when the Source has re- established vSafe5V on VBUS. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an OVP event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if OVP continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over voltage. Page 338 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.9.3 Over Temperature Protection Sinks Shall implement over temperature protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Sink. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Sink implementation. Sinks Shall attempt to send Hard Reset Signaling when over temperature protection engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The over temperature protection response May engage at either the Port or system level. Systems or ports that have engaged over temperature protection Should attempt to resume USB Default Operation after sufficient cooling is achieved and May latch off to protect the Port or system. The definition of sufficient cooling is left to the discretion of the Sink implementation. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an over temperature event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. 7.2.9.4 Over Current Protection Sinks that operate with a Programmable Power Supply Shall implement their own internal current protection mechanism to protect against internal VBUS current faults as well as erratic Source current regulation. The Sink Shall never draw higher current than the Maximum Current value in the PPS APDO. 7.2.10 Fast Role Swap As described in Section 7.1.13, "Fast Role Swap" a Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port that supports DRP. This configuration is shown in Figure 7.16, "VBUS Power during Fast Role Swap". The Host DRP, upon establishing an Explicit Contract, Shall query the Initial Source's Sink Capabilities to determine whether the Initial Source supports Fast Role Swap, and what level of current it requires. If the Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap required USB Type-C Current bits set, and the Host DRP is able to source the requested current at 5V, the Host DRP May arm itself for Fast Role Swap. If the Host DRP has not queried the Sink Capabilities from the Initial Source, or if the Sink_Capabilities Message reports no Fast Role Swap support or a current that is beyond what the Host DRP is able or willing to source in the event of a Fast Role Swap, the Host DRP Shall Not arm itself for Fast Role Swap and Shall Ignore any Fast Role Swap Requests that are detected. When the Host DRP that supports Fast Role Swap detects the FFast Role Swap Request, the Host DRP Shall stop sinking current and Shall be ready and able to source vSafe5V if the residual VBUS voltage level at the Host DRP connector is greater than vSafe5V. When the residual VBUS voltage level at the Host DRP connector discharges below vSafe5V(min) the Host DRP as the New Source Shall supply vSafe5V to the Hub DRP within tSrcFRSwap. The Host DRP Shall Not enable VBUS discharge circuitry when changing Power Roles from Initial Sink to New Source. The New Source Shall supply vSafe5V at USB Type-C Current (see [USB Type-C 2.4]) at the value Advertised in the Fast Role Swap required USB Type-C Current field (see Section 6.4.1.3.1.6, "Fast Role Swap USB Type-C Current"). All Source requirements Shall apply to the New Source after the Fast Role Swap is complete The Fast Role Swap response of the Hub DRP is described in Section 7.1.13, "Fast Role Swap" since the Hub DRP is operating as the Initial Source prior to the Fast Role Swap. After the Host DRP is providing VBUS power to the Hub DRP, a PS_RDY Message Shall be sent to the Hub DRP as defined by the Fast Role Swap Request and the AMS detailed in Section 7.3.4, "Transitions Caused by Fast Role Swap". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 339 7.3 Transitions The following sections illustrate the power supply's response to various types of Negotiations. The Negotiations are triggered by certain Messages or Signaling. It provides examples of the transitions and is organized around each of the Messages and Signals that result in a response from the power supply. The response to a Message or Signal can result in different transitions depending upon the power supply's starting conditions and the requested change.  Transitions caused by a Request Message:  Generic transition between (A)PDO s:  Increase the current.  Increase the voltage.  Increase the voltage and the current.  Increase the voltage and decrease the current.  Decrease the voltage and increase the current.  Decrease the voltage and the current.  No change in Current or voltage.  Transitions within the same PDO (Fixed Supply, Battery Supply, Variable Supply):  Increase the current.  Decrease the current.  No change in current.  Transitions within the same PPS APDO:  Increasing the Programmable Power Supply (PPS) voltage.  Decreasing the Programmable Power Supply (PPS) voltage.  Increasing the Programmable Power Supply (PPS) Current.  Decreasing the Programmable Power Supply (PPS) Current.  Same Request Programmable Power Supply (PPS).  Transitions within the same AVS APDO:  Increasing the Adjustable Voltage Supply (AVS) voltage  Decreasing the Adjustable Voltage Supply (AVS) voltage  Same Request Adjustable Voltage Supply (AVS)  Transitions caused by the PR_Swap Message:  Source requests a Power Role Swap  Sink requests a Power Role Swap  Transitions caused by Hard Reset Signaling:  Source issues Hard Reset Signaling.  Sink issues Hard Reset Signaling.  Transitions caused by the Fast Role Swap Request:  Source asserts Rd at its preferred [USB Type-C 2.4] current. Page 340 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1 Transitions caused by a Request Message This section describes transitions that are caused by a Request Message. 7.3.1.1 Changing the Source between Different (A)PDOs In these transition descriptions the term (A)PDO is used to describe any Power Data Object, regardless of whether it is a PDO or an APDO in the Capabilities Message. This section describes transitions in response to a Request Message:  From one (A)PDO to another (A)PDO  From an Implicit Contract to an Explicit Contract  From [USB Type-C 2.4]operation to the First Explicit Contract These transitions usually result in a voltage change but is not required. The interaction of the Device Policy Manager, the Port Policy Engine and the Power Supply that Shall be followed when increasing the current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current" and Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The Source voltage as the transition starts Shall be any voltage within the Valid VBUS range of the previous Source PDO or APDO. The Source voltage after the transition is complete Shall be any voltage within the Valid VBUS range of the New Source PDO or APDO. The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current" and Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In this figure, the Sink has previously sent a Request Message to the Source. The voltage is considered to increase if the change from VOLD to VNEW is greater than vSmallStep. The determination Shall be based on the nominal (A)PDO voltage before and after, unless either (A)PDO is Battery Supply or Variable Supply when the worst case of the following is assumed in making this determination.  Minimum voltage to voltage.  Minimum voltage to Maximum voltage.  Voltage to Maximum voltage. The following sections begin with a description of the generic process followed by more specific examples of the most common transitions. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 341 7.3.1.1.1 Examples of changes from one (A)PDO to another (A)PDO The seven examples of (A)PDO change transitions below illustrate the most common transitions. 7.3.1.1.1.1 Increasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage is shown in Figure 7.22, "Transition Diagram for Increasing the Voltage". The sequence that Shall be followed is described in Table 7.1, "Sequence Description for Increasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.22, "Transition Diagram for Increasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 342 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.22 Transition Diagram for Increasing the Voltage t3 t1 t2 Source VOLD Source VNEW Source × V 4 3 7 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply 8 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,2/' Sink ” IOLD ” IOLD ” IOLD Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) VNEW I1 ... § Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 343 Table 7.1 Sequence Description for Increasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 344 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.2 Increasing the Voltage and Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current". The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.23, "Transition Diagram for Increasing the Voltage and Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 345 Figure 7.23 Transition Diagram for Increasing the Voltage and Current t3 Source VOLD Source VNEW Source × V × I 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ”INEW Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD VNEW 3 7 I1 § ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) t2 t1 Page 346 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.2 Sequence Diagram for Increasing the Voltage and Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out, the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 347 7.3.1.1.1.3 Increasing the Voltage and Decreasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and decreasing the current is shown in Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current". The sequence that Shall be followed is described in Table 7.3, "Sequence Description for Increasing the Voltage and Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current", the Sink has previously sent a Request Message to the Source. Page 348 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.24 Transition Diagram for Increasing the Voltage and Decreasing the Current t3 t1 Source VOLD Source VNEW Source × V ØI 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW I1 Sink to Sink Standby Sink Standby to Sink Sink iSnkStdBy VNEW VOLD 3 7 ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) § t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 349 Table 7.3 Sequence Description for Increasing the Voltage and Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 350 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.4 Decreasing the Voltage and Increasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and increasing the current is shown in Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The sequence that Shall be followed is described in Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 351 Figure 7.25 Transition Diagram for Decreasing the Voltage and Increasing the Current t2 Source VOLD Source VNEW Source Ø V × I 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW VNEW VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink × I ... 6 7 t1 Page 352 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.4 Sequence Description for Decreasing the Voltage and Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the PS_RDY Message from the Source and tells the Device Policy Manager it is okay to operate at the new power level. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 353 7.3.1.1.1.5 Decreasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage is shown in Figure 7.26, "Transition Diagram for Decreasing the Voltage". The sequence that Shall be followed is described in Table 7.5, "Sequence Description for Decreasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.26, "Transition Diagram for Decreasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 354 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.26 Transition Diagram for Decreasing the Voltage t Source VOLD Source Ø V 3 Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”IOLD VOLD ” IOLD ” IOLD VNEW Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 355 Table 7.5 Sequence Description for Decreasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 356 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.6 Decreasing the Voltage and the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and current is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.6, "Sequence Description for Decreasing the Voltage and the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.27, "Transition Diagram for Decreasing the Voltage and the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 357 Figure 7.27 Transition Diagram for Decreasing the Voltage and the Current t1 t2 Source Ø V Ø I 4 Source VOLD Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”INEW Sink ”IOLD ” IOLD ” INEW Sink Ø I VNEW VOLD 3 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Page 358 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.6 Sequence Description for Decreasing the Voltage and the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 359 7.3.1.1.1.7 No change in Current or Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while the Sink requests the same voltage and Current as it is currently operating at is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.7, "Sequence Description for no change in Current or Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.28, "Transition Diagram for no change in Current or Voltage", the Sink has previously sent a Request Message to the Source. Page 360 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.28 Transition Diagram for no change in Current or Voltage Table 7.7 Sequence Description for no change in Current or Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine waits tSrcTransition then sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine evaluates the PS_RDY Message. Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink ”IOLD VBUS doesn’t change Source VOLD Current doesn’t change Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tSrcTransition Good CRC Good CRC tSrcTransReq Vold Source VOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 361 7.3.1.2 Transitions within the same Fixed, Battery or Variable PDO or between Different (A)PDOs 7.3.1.2.1 Increasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current without changing the voltage is shown in Figure 7.29, "Transition Diagram for Increasing the Current". The sequence that Shall be followed is described in Table 7.8, "Sequence Description for Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.29, "Transition Diagram for Increasing the Current", the Sink has previously sent a Request Message to the Source. Page 362 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.29 Transition Diagram for Increasing the Current Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Sink ”INEW Source Port Voltage Sink Port Current Sink ”IOLD ” IOLD ” INEW Sink × I VBUS doesn’t change Source × I 3 6 ... 7 § Source VOLD Source VOLD Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Port to Port Messaging Good CRC tSrcTransReq Good CRC Sink Port Policy Engine t1 t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 363 Table 7.8 Sequence Description for Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t2) depends on the magnitude of the load change. Page 364 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.2.2 Decreasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current without changing the voltage is shown in Figure 7.30, "Transition Diagram for Decreasing the Current". The sequence that Shall be followed is described in Table 7.9, "Sequence Description for Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.30, "Transition Diagram for Decreasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 365 Figure 7.30 Transition Diagram for Decreasing the Current Source VOLD Source VOLD Sink ”IOLD Sink ”INEW VBUS does not change Source Ø I 4 3 ” IOLD ” INEW Sink Ø I Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC t1 t2 Page 366 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.9 Sequence Description for Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. Policy Engine tells the Device Policy Manager to instruct the power supply to reduce power consumption. 3 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 367 7.3.1.3 Changing Voltage or Current within the same PPS APDO 7.3.1.3.1 Increasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.10, "Sequence Description for Increasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Page 368 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.31 Transition Diagram for Increasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Current may change (not to exceed negotiated current) Source CL Current Sink VBUS Current Sink Port Current VOLD Source Port Voltage VNEW Source VBUS Voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 369 Table 7.10 Sequence Description for Increasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to increase its output voltage. The Programmable Power Supply new voltage set- point Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new set-point and whether VBUS is at the corresponding new level, or if the supply is operating in CL mode. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 370 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.2 Decreasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.11, "Sequence Description for Decreasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 371 Figure 7.32 Transition Diagram for Decreasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Source CL Current Current may change (not to exceed negotiated current) Sink VBUS Current Sink Port Current Page 372 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.11 Sequence Description for Decreasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to decrease its output voltage. The Programmable Power Supply new voltage set- point (corresponding to vPpsNew) Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 373 7.3.1.3.3 Increasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current limit in the same APDO, not exceeding the maximum for that APDO and without changing the requested voltage is shown in Figure 7.33, "Transition Diagram for increasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.12, "Sequence Description for increasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.33, "Transition Diagram for increasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. The Sink May draw current equal to the increasing Current Limit of the Source before it has received the PS_RDY Message for the new Request. Page 374 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.33 Transition Diagram for increasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ĺ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 375 Table 7.12 Sequence Description for increasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Power Supply increases its Current Limit set- point to the new requested value. The Sink draws current according to the increased Current Limit of the Source. 4 The Policy Engine waits tPpsSrcTransSmall then sends the PS_RDY Message to the Sink starting within tPpsCLProgramSettle of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. 6 Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message and tells the Device Policy Manager it can increase the current up to the requested value without the Source going into CL mode. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink increases its current. Page 376 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.4 Decreasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current limit in the same APDO, not exceeding the minimum for that APDO and without changing the requested voltage is shown in Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.13, "Sequence Description for decreasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 377 Figure 7.34 Transition Diagram for decreasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ļ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Set-point V does not change, only resulting V Page 378 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.13 Sequence Description for decreasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and instructs the Sink to reduce its current to below the new Negotiated current level and starts the PSTransitionTimer. 3 The Power Supply decreases its Current Limit set- point to the new Negotiated value. The Sink reduces its current to less than the new Negotiated current to prevent the Source from going into Current Limit. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Policy Engine receives the PS_RDY Message. 6 Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink is allowed to draw INEW but must be aware the voltage on VBUS can drop doing so. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 379 7.3.1.3.5 Same Request Programmable Power Supply (PPS) The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current is shown in Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode". The sequence that Shall be followed is described in Table 7.14, "Sequence Description for no change in Current or Voltage in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode", the Sink has previ- ously sent a Request Message to the Source. Page 380 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.35 Transition Diagram for no change in Current or Voltage in PPS mode Table 7.14 Sequence Description for no change in Current or Voltage in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and starts the PSTransitionTimer. 3 The Policy Engine then sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Source IOLD Sink ” IOLD Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD Sink Port Current Source CL Current CL doesn’t change Current doesn’t change VBUS doesn’t change Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 381 7.3.1.4 Changing Voltage or Current within the same AVS APDO 7.3.1.4.1 Increasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.15, "Sequence Description for Increasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed inTable 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage", the Sink has pre- viously sent a Request Message to the Source. Page 382 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.36 Transition Diagram for Increasing the Adjustable Power Supply Voltage AVS Transition Interval Source VOLD Source VNEW Sink draws current continuously for voltage changes less than or equal to vAvsSmallStep. For larger voltage changes, the Sink reduces to iSnkStdby. IOLD VOLD Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Depends on magnitude of AVS voltage change Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 383 Table 7.15 Sequence Description for Increasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. If the voltage increase is larger than vAvsSmallStep, the Sink Shall reduce its current draw to iSnkStdby within tSnkStdby. The reduction to iSnkStdby is not required if the voltage increase is less than or equal to vAvsSmallStep. 3 After sending the Accept Message, the AVS starts to increase its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point. The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 384 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.4.2 Decreasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage". The sequence that Shall be followed is described in Table 7.16, "Sequence Description for Decreasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 385 Figure 7.37 Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage AVS Transition Interval Source VOLD Source VNEW ”IOLD VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Sink ”IOLD Page 386 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.16 Sequence Description for Decreasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the AVS starts to decrease its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vAvsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 387 7.3.1.4.3 Same Request Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current as shown in Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode". The sequence that Shall be followed is described in Table 7.17, "Sequence Description for no change in Current or Voltage in AVS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode", the Sink has previ- ously sent a Request Message to the Source. Figure 7.38 Transition Diagram for no change in Current or Voltage in AVS mode Table 7.17 Sequence Description for no change in Current or Voltage in AVS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 4 Protocol Layer receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Current doesn’t change VBUS doesn’t change Source Port Policy Engine Sink Port Policy Engine Source Port Voltage Sink Port Current Port to Port Messaging Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Page 388 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2 Transitions Caused by Power Role Swap 7.3.2.1 Sink Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink requested Power Role Swap is shown in Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.18, "Sequence Description for a Sink Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap", the Sink has previously sent a PR_Swap Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 389 Figure 7.39 Transition Diagram for a Sink Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 3 4 7 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSSourceOffTimer tSrcTransition Good CRC tSrcTransOff Good CRC PSSourceOnTimer Send PS_RDY Evaluate PS_RDY Good CRC 8 9 tSrcTransOn Page 390 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.18 Sequence Description for a Sink Requested Power Role Swap Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port 1 Policy Engine sends the Accept Message to the Initial Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Initial Source. Policy Engine then starts the PSSourceOffTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition min. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 5 The power supply is ready, and the Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. 6 Protocol Layer receives the GoodCRC Message from the device that will become the New Source. Policy Engine starts the PSSourceOnTimer. Upon sending the PS_RDY Message and receiving the GoodCRC Message the Initial Source is ready to be the New Sink. The Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine the stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 8 Policy Engine receives the PS_RDY Message from the Source. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 391 9 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 10 The power supply as the New Sink transitions from Swap Standby and begins to drawing the current allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.18 Sequence Description for a Sink Requested Power Role Swap (Continued) Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port Page 392 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2.2 Source Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source requested Power Role Swap is shown in Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.19, "Sequence Description for a Source Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap", the Source has previously sent a PR_Swap Message to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 393 Figure 7.40 Transition Diagram for a Source Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 2a 4 6 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSSourceOffTimer (running) tSrcTransition Good CRC Good CRC PSSourceOnTimer (running) Send PS_RDY Evaluate PS_RDY Good CRC 7 9 Page 394 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.19 Sequence Description for a Source Requested Power Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port 1 Policy Engine receives the Accept Message. Policy Engine sends the Accept Message to the Initial Source. 2 Protocol Layer sends the GoodCRC Message to the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer receives the GoodCRC Message from the Initial Source. Policy Engine starts the PSSourceOffTimer. 2a The Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby. The power supply Shall complete the transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). 3 tSrcTransition after the GoodCRC Message was sent the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY. 5 Protocol Layer receives the GoodCRC Message from the soon to be New Source. Policy Engine starts the PSSourceOnTimer. At this point the Initial Source is ready to be the New Sink. Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine then stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before the PSSourceOffTimer times out the Sink starts sending Hard Reset Signaling. 6 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 7 Policy Engine receives the PS_RDY Message. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 395 8 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 9 The power supply as the New Sink transitions from Swap Standby to drawing the power allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The New Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.19 Sequence Description for a Source Requested Power Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 396 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3 Transitions Caused by Hard Reset 7.3.3.1 Source Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source Initiated Hard Reset is shown in Figure 7.41, "Transition Diagram for a Source Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.20, "Sequence Description for a Source Initiated Hard Reset". The timing parameters that Shall be applied are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 397 Figure 7.41 Transition Diagram for a Source Initiated Hard Reset Table 7.20 Sequence Description for a Source Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Sink. Sink receives Hard Reset Signaling. 2 Policy Engine is informed of the Hard Reset. Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine waits tPSHardReset after sending Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 5 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 Source VOLD Send Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 vSafe5V Default current draw § § Source vSafe5V 4 Source vSafe0V Sink ” IOLD Ready to recover and power up Source Recover tSrcRecover 5 Process Hard Reset tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current 2 t2 t1 Page 398 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3.2 Sink Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink Initiated Hard Reset is shown in Figure 7.42, "Transition Diagram for a Sink Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.21, "Sequence Description for a Sink Initiated Hard Reset". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 399 Figure 7.42 Transition Diagram for a Sink Initiated Hard Reset Table 7.21 Sequence Description for a Sink Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Source. 2 Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager. The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine is informed of the Hard Reset. 5 Policy Engine waits tPSHardReset after receiving Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 6 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 t2 Send Hard Reset Evaluate Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 4 vSafe5V Defalt current draw § § Source vSafe5V 5 Source vSafe0V Sink ” IOLD Source VOLD Ready to recover and power up Source Recover tSrcRecover 6 tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Process Hard Reset 2 t1 Page 400 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.4 Transitions Caused by Fast Role Swap 7.3.4.1 Fast Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Fast Role Swap is shown in Figure 7.43, "Transition Diagram for Fast Role Swap". The parallel sequences that Shall be followed are described in Table 7.22, "Sequence Description for Fast Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Negotiations between the New Source and the New Sink May occur after the New Source sends the final PS_RDY Message. Note: In Figure 7.43, "Transition Diagram for Fast Role Swap". and Table 7.22, "Sequence Description for Fast Role Swap" numbers are used to indicate Message related steps and letters are used to indicate other events. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 401 Figure 7.43 Transition Diagram for Fast Role Swap Rp Changed to Rd Signal Fast Swap Detect Fast Swap Old Sink New Sink Old Source A B 2 C Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Path Sink Port Device Policy Mgr Sink Port Power Path Source Port Voltage Sink Port Current Port to Port Signaling & Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Stops Send FR_Swap 1 Send Accept Evaluate FR_Swap New Source = vSafe5V Evaluate Accept 3 4 Send PS_RDY Evaluate PS_RDY D1 Sink 5 6 Source VBUS< vSafe5V Send PS_RDY 7 VBUS< vSafe5V Source VBUS Source vSafe5V D2 E Ready & Able to Source vSafe5V Evaluate PS_RDY 8 tFRSwapInit Rd Changed to Rp F G 0 A < tSrcFRSwap discharging Sink 0 V Any voltage > vSafe5V No current may be drawn while VBUS is below vSafe5V Page 402 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.22 Sequence Description for Fast Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Fast Role Swap Request and Power Transition A The Source connected to the Hub UFP (see Figure 7.16, "VBUS Power during Fast Role Swap") stops sourcing VBUS. B Policy Engine sends the Fast Role Swap Request to the Initial Sink on the CC wire. When VBUS < vSafe5V (min), it tells the Device Policy Manager not to draw more than iSnkStdby until the tSnkFRSwap timer has elapsed. C Policy Engine detects the Fast Role Swap Request on the CC wire from the Initial Source and Shall send the FR_Swap Message back to the Initial Source (that is no longer powering VBUS) within time tFRSwapInit. D1 The Policy Engine monitors for VBUS ≤ vSafe5V so that a PS_RDY Message can be sent to the New Source at Step 5 of the messaging sequence. D2 The Policy Engine monitors for VBUS ≤ vSafe5V so the Initial Sink can assume the Power Role of New Source and begin to source VBUS. E When VBUS = vSafe5V the New Source May provide power to VBUS. When VBUS < vSafe5V the New Source Shall provide power to VBUS within tSrcFRSwap. Once the New Source is providing power, the PS_RDY Message can be sent to the New Sink at Step 7 of the messaging sequence. F The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]) before the New Sink sends the PS_RDY Message at Step 5 to the New Source. G The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]) before the New Source sends the PS_RDY Message at Step 7 to the New Sink. Fast Role Swap Message Sequence 1 Policy Engine receives the FR_Swap Message from the Initial Sink that is transitioning to be the New Source. Policy Engine sends the FR_Swap Message to the Initial Source (that is no longer powering VBUS) after detecting the Fast Role Swap Request at Step C. 2 Protocol Layer sends the GoodCRC Message to the Initial Sink. Policy Engine then evaluates the FR_Swap Message. Protocol Layer receives the GoodCRC Message from the Initial Source. 3 Policy Engine sends an Accept Message to the Initial Sink that is transitioning to be the New Source. Policy Engine receives the Accept Message from the Initial Source that is transitioning to be the New Sink. 4 Protocol Layer receives the GoodCRC Message from the Initial Sink that is transitioning to be the New Source. Protocol Layer sends the GoodCRC Message to the Initial Source that is transitioning to be the New Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 403 5 Policy Engine sends a PS_RDY Message to the Initial Sink that is transitioning to be the New Source. The Policy Engine Shall start the PS_RDY Message at least tFRSwap5V after it has sent the Accept Message, and when Step D1 has also been completed. Policy Engine receives the PS_RDY Message from the New Sink. 6 Protocol Layer receives the GoodCRC Message from the New Source. Protocol Layer sends the GoodCRC Message from the Initial Sink that has completed the transition to New Source. Policy Engine then evaluates the PS_RDY Message. 7 Policy Engine receives the PS_RDY Message from the New Source. Policy Engine sends a PS_RDY Message to the New Sink. The Policy Engine Shall wait for Step E before sending the PS_RDY Message, and Shall send the PS_RDY Message within tFRSwapComplete of receiving the PS_RDY Message from the Initial Source Port. Table 7.22 Sequence Description for Fast Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 404 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.4 Electrical Parameters 7.4.1 Source Electrical Parameters The Source Electrical Parameters that Shall be followed are specified in Table 7.23, "Source Electrical Parameters". Table 7.23 Source Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSrcBulk Source bulk capacitance when a Port is powered from a dedicated supply.1 10 µF Section 7.1.2 cSrcBulkShared Source bulk capacitance when a Port is powered from a shared supply.1 120 µF Section 7.1.2 DNL (Differential Non- Linearity) Deviation between ideal analog values corresponding to adjacent input digital values -1 0 +1 LSB Section 7.1.4.2.1 iPpsCLMin SPR PPS Minimum Current Limit setting. 1 A Section 7.1.4.2.2 iPpsCLNew Current Limit accuracy Section 7.1.4.2.2 1A ≤ Operating Current ≤ 3A -150 150 mA Operating current > 3A -5 5 % iPpsCLStep SPR PPS Current Limit programming step size (1 LSB). 50 mA Section 7.1.4.2.2 iPpsCLLoadReleaseRate Maximum load decrease slew rate during Current Limit set-point changes. -150 mA/µs Section 7.1.4.2.2 iPpsCLLoadStepRate Maximum load increase slew rate during Current Limit set-point changes. 150 mA/µs Section 7.1.4.2.2 iPpsCLTransient Allowed output current overshoot when a load increase occurs while in CL mode. New load + 100 mA Section 7.1.4.2.2 Allowed output current undershoot when a load decrease occurs while in CL mode. New load – 100 mA 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 405 iPpsCVCLTransient CV to CL transient current bounds assuming the Operating Voltage reduction of Section 7.2.3.1, "Programmable Power Supply Sink Standby". iPpsCLNe w - 100 New load + 500 mA Section 7.1.4.2.2 tAvsTransient The maximum time for the AVS to be between vAvsNew and vAvsValid in response to a load transient. 5 ms Section 7.1.8.4 tAvsSrcTransLarge The time the AVS set- point Shall transition between requested voltages for steps larger than vAvsSmallStep. 0 700 ms Section 7.1.4.3.1 tAvsSrcTransSmall The time the AVS set- point Shall transition between requested voltages for steps smaller than vAvsSmallStep. 0 50 ms Section 7.1.4.3.1 tNewSnk Time allowed for an Initial Source in Swap Standby to transition New Sink operation. 15 ms Section 7.1.10 Figure 7.39 Figure 7.40 tPpsCLCVTransient CL to CV transient voltage settling time. 275 ms Section 7.1.4.2.2 tPpsCLProgramSettle SPR PPS Current Limit programming settling time. 250 ms Section 7.1.4.2.2 tPpsCLSettle CL load transient current settling time. 250 ms Section 7.1.4.2.2 tPpsCVCLTransient CV to CL transient settling time. 250 ms Section 7.1.8.3 tPpsSrcTransLarge The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps larger than vPpsSmallStep. 0 275 ms Section 7.3.1.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 406 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tPpsSrcTransSmall The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps less than or equal to vPpsSmallStep. 0 25 ms Section 7.3.1.3 tPpsTransient The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is greater than or equal to 60mA. 5 ms Section 7.1.8.3 The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8.3 tSrcFRSwap Time from the Initial Sink detecting that VBUS has dropped below vSafe5V until the Initial Sink/new Source is able to supply USB Type-C Current (see [USB Type-C 2.4]) 150 µs Section 7.1.13 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 407 tSrcReady SPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies only to SPR Mode voltage transitions. 285 ms Figure 7.2 Figure 7.3 EPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 720 tSrcRecover SPR Mode Time allotted for the Source to recover. 0.66 1.0 s Section 7.1.5 EPR Mode 1.085 1.425 tSrcSettle SPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vSrcNew. Applies only to SPR Mode voltage transitions. 275 ms Figure 7.2 EPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vAvsNew. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 700 tSrcSwapStdby The maximum time for the Source to transition to Swap Standby. 650 ms Section 7.1.10 Figure 7.17 Figure 7.18 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 408 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tSrcTransient The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is greater or equal to than 60mA. 5 ms Section 7.1.8 The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8 tSrcTransition The time the Source Shall wait before transitioning the power supply to ensure that the Sink has sufficient time to prepare (does not apply to transitions within the same PPS or AVS APDO). 25 35 ms Section 7.3 tSrcTransOff SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the PR_Swap Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 690 ms Section 7.3.2 tSrcTransOn Time from the last bit of the GoodCRC Message acknowledging the PS_RDY Message sent by the new Source, in response to the PR_Swap Message until the PS_RDY Message must be started. 280 ms Section 7.3.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 409 tSrcTransReq SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 325 ms Section 7.3 EPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 760 ms Section 7.3 tSrcTurnOn Transition time from vSafe0V to vSafe5V. 275 ms Figure 7.10 Table 7.20 Table 7.21 vAvsMaxVoltage Maximum Voltage Field in the AVS APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.3.1 vAvsMinVoltage Minimum Voltage Field in the AVS APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.3.1 vAvsNew Adjustable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.4 vAvsSlewNeg AVS maximum slew rate for negative voltage changes. -30 mV/µs Section 7.1.8.4 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 410 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vAvsSlewPos AVS maximum slew rate for positive voltage changes. 30 mV/µs Section 7.1.8.4 vAvsSmallStep AVS step size defined as a small step relative to the previous vAvsNew. -1.0 1.0 V Section 7.1.4.3.1 vAvsStep AVS voltage programming step size. 100 mV Section 7.1.8.4 vAvsValid The range in addition to vAvsNew which the AVS output is considered Valid during and after a transition as well as in response to a transient load condition. -0.5 0.5 V Section 7.1.8.4 vPpsCLCVTransient CL to CV load transient voltage bounds. Operating Voltage * 0.95 – 0.1V Operating Voltage * 1.05 + 0.1V V Section 7.1.4.2.2 vPpsMaxVoltage Maximum Voltage Field in the Programmable Power Supply APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.2.1 vPpsMinVoltage Minimum Voltage Field in the Programmable Power Supply APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.2.1 vPpsNew Programmable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.3 vPpsShutdown The voltage at which the SPR PPS shuts down when operating in CL. APDO Minimum Voltage * 0.85 APDO Minimum Voltage * 0.95 V Section 7.1.4.2.2 vPpsSlewNeg Programmable Power Supply maximum slew rate for negative voltage changes -30 mV/µs Section 7.1.8.3 vPpsSlewPos Programmable Power Supply maximum slew rate for positive voltage changes 30 mV/µs Section 7.1.8.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 411 vPpsSmallStep PPS Step size defined as a small step relative to the previous vPpsNew. -500 500 mV Section 7.1.4.2.2 vPpsStep PPS voltage programming step size (1 LSB). 20 mV Section 7.1.8.3 vPpsValid The range in addition to vPpsNew which the Programmable Power Supply output is considered Valid in response to a load step. -0.1 0.1 V Section 7.1.8.3 vSmallStep VBUS step size increase defined as a small step relative to the previous VBUS when Requesting a different (A)PDO. 500 mV Section 7.1.4.3.1 vSrcNeg Most negative voltage allowed during transition. -0.3 V Figure 7.10 vSrcNew Fixed Supply output measured at the Source receptacle. PDO Voltage *0.95 PDO Voltage PDO Voltage *1.05 V Table 7.2 Variable Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V Battery Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V vSrcPeak The range that a Fixed Supply or EPR AVS in Peak Current operation is allowed when overload conditions occur. PDO Voltage *0.90 PDO Voltage *1.05 V Table 6.10 Table 6.16 Figure 7.14 vSrcSlewNeg Maximum slew rate allowed for negative voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. -30 mV/µs Section 7.1.4.2 Table 7.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 412 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vSrcSlewPos Maximum slew rate allowed for positive voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. 30 mV/µs Section 7.1.4 Figure 7.2 vSrcValid The range in addition to vSrcNew which a newly Negotiated voltage is considered Valid during and after a transition as well as in response to a transient load condition. This range also applies to vSafe5V. -0.5 0.5 V Figure 7.2 Figure 7.3 Section 7.1.8 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 413 7.4.2 Sink Electrical Parameters The Sink Electrical Parameters that Shall be followed are specified in Table 7.24, "Sink Electrical Parameters". Table 7.24 Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSnkBulk Sink bulk capacitance on VBUS at Attach and during FRS after the Initial Source stops sourcing and prior to establishing the First Explicit Contract (see Appendix E, "FRS System Level Example" for an example).1 See [USB 3.2] Section 7.2.2 [USB 3.2] cSnkBulkPd Bulk capacitance on VBUS a Sink is allowed after a successful Negotiation.1 100 µF Section 7.2.2 iLoadReleaseRate Load release di/dt. -150 mA/ µs Section 7.2.6 iLoadStepRate Load step di/dt. 150 mA/ µs Section 7.2.6 iNewFrsSink Maximum current the New Sink can draw during a Fast Role Swap until the New Source applies Rp. Matches the required Fast Role Swap required USB Type-C Current Current field of the Fixed Supply PDO of the Initial Source’s Sink_Capabilities Message. Default USB current or 1.5 or 3.0 A Section 7.1.13 iOvershoot Positive or negative overshoot when a load change occurs less than or equal to iLoadStepRate; relative to the settled value after the load change. -230 230 mA Section 7.2.6 iPpsCLLoadStep Maximum Current set-point change while operating in CL mode. -500 500 mA Section 7.2.3.1 iSafe0mA Maximum current a Sink is allowed to draw when VBUS is driven to vSafe0V. 1.0 mA Figure 7.29 Figure 7.30 iSnkStdby Maximum current during voltage transition. 500 mA Section 7.2.3 iSnkSwapStdby Maximum current a Sink can draw during Swap Standby. Ideally this current is very near to 0 mA largely influenced by Port leakage current. 2.5 mA Section 7.2.7 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Page 414 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 pHubSusp Suspend power consumption for a Hub. 25mW + 25mW per downstream Port for up to 4 ports. 125 mW Section 7.2.3 pSnkSusp Suspend power consumption for a peripheral device. 25 mW Section 7.2.3 tNewSrc Maximum time allowed for an Initial Sink in Swap Standby to transition to New Source operation. 275 ms Section 7.2.7 Table 7.18 Table 7.19 tSnkFRSwap Time during a Fast Role Swap when the New Sink can draw no more than iSnkStdby. 200 µs Section 7.1.13 tSnkHardResetPrepare Time allotted for the Sink power electronics to prepare for a Hard Reset. 15 ms Table 7.12 tSnkNewPower Maximum transition time between power levels. 15 ms Section 7.2.3 tSnkRecover Time for the Sink to resume USB Default Operation. 150 ms Table 7.20 tSnkStdby Time to transition to Sink Standby from Sink. 15 ms Section 7.2.3 tSnkSwapStdby Maximum time for the Sink to transition to Swap Standby. 15 ms Section 7.2.7 vEprMax Highest voltage an EPR Sink is expected to tolerate 55 V Section 7.2.9.2 vSprMax Highest voltage an SPR Sink is expected to tolerate 24 V Section 7.2.9.2 Table 7.24 Sink Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 415 7.4.3 Common Electrical Parameters Electrical Parameters that are common to both the Source and the Sink that Shall be followed are specified in Table 7.25, "Common Source/Sink Electrical Parameters"”. Table 7.25 Common Source/Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference tSafe0V Time to reach vSafe0V max. 650 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tSafe5V Time to reach vSafe5V max. 275 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tVCONNReapplied When the UFP is the VCONN Source: time from the last bit of the GoodCRC acknowledging the PS_RDY Message before reapplying VCONN. When the DFP is the VCONN Source: time from when VCONN drops below vRaReconnect. 10 20 ms Figure 7.19 Figure 7.20 tVCONNValid Time from tVCONNReapplied until VCONN is within vVconnValid (see [USB Type-C 2.4]).1 0 5 ms Figure 7.19 Figure 7.20 tVCONNZero Time from the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message until VCONN is below vRaReconnect (see [USB Type-C 2.4]). 125 ms Figure 7.19 Figure 7.20 vSafe0V Safe operating voltage at “zero volts”. 0 0.8 V Section 7.1.5 vSafe5V Safe operating voltage at 5V. See [USB 2.0] and [USB 3.2] for allowable VBUS voltage range. 4.75 5.5 V Section 7.1.5 1) tVCONNStable (See [USB Type-C 2.4]) still applies.
8 - Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 416)
Page 416 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy 8.1 Overview This section describes the Device Policy and Policy Engine that implements it. For an overview of the architecture and how the Device Policy Manager fits into this architecture, please see Section 2.6, "Architectural Overview". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 417 8.2 Device Policy Manager The Device Policy Manager is responsible for managing the power used by one or more USB Power Delivery ports. In order to have sufficient knowledge to complete this task it needs relevant information about the device it resides in. Firstly, it has a priori knowledge of the device including the Capabilities of the power supply and the receptacles on each Port since these will for example have specific current ratings. It also has to know information from the USB-C® Port Control module regarding cable insertion, type and rating of cable etc. It also has to have information from the power supply about changes in its Capabilities as well as being able to request power supply changes. With all of this information the Device Policy Manager is able to provide up to date information regarding the Capabilities available to a specific Port and to manage the power resources within the device. When working out the Capabilities for a given Source Port the Device Policy Manager will take into account firstly the current rating of the Port's receptacle and whether the inserted cable is PD or non-PD rated and if so, what is the capability of the plug. This will set an upper bound for the Capabilities which might be offered. After this the Device Policy Manager will consider the available power supply resources since this will bound which voltages and currents might be offered. Finally, the Device Policy Manager will consider what power is currently allocated to other ports, which power is in the Power Reserve and any other amendments to Policy from the System Policy Manager. The Device Policy Manager will offer a set of Capabilities within the bounds detailed above. When selecting a capability for a given Sink Port the Device Policy Manager will look at the Capabilities offered by the Source. This will set an upper bound for the Capabilities which might be requested. The Device Policy Manager will also consider which Capabilities are required by the Sink in order to operate. If an appropriate match for voltage and Current can be found within the limits of the receptacle and cable, then this will be requested from the Source. If an appropriate match cannot be found then a request for an offered voltage and current will be made, along with an indication of a Capabilities Mismatch. USB PD defines two types of power sources:  Predefined voltage sources (Fixed Supply, Variable Supply and Battery Supply)  Programmable voltage sources:  Programmable Power Supply (PPS)  Adjustable Voltage Supply (AVS) The first are generally used for classic charging wherein the Charger electronics reside inside the Sink. The Device Policy Manager in the Sink requests a fixed voltage from the list of PDOs offered by the Source and which is converted internally to charge the Sink's Battery and/or power its function. The second moves the Charger electronics that manage the voltage control outside the Sink and back into the Source itself. When in SPR PPS Mode, the Device Policy Manager in the Sink requests a specific voltage with a 20mV accuracy and sets a current limit. Unlike traditional USB where Sinks are responsible for limiting the current, they consume, the SPR PPS Source limits the current to what the Sink has requested. When operating in, the Device Policy Manager in the Sink requests a specific voltage with a 100mV accuracy and requests a maximum current it is allowed to draw. Note: The AVS Sources unlike SPR PPS Sources do not support current limit mode. A Sink operating in is respon- sible not to draw more current than it requests. The process to request power is the same for both types of power Sources although the actual format and contents of the request are slightly different. The primary operational differences are:  A Sink that is using SPR PPS is required to periodically sent requests to let the Source know it is still alive and communicating. When this communication fails a Hard Reset results.  A Sink operating in SPR Mode has no special timing requirements.  A Sink operating in EPR Mode is required to periodically communicate with the Source to let it know it is still operational. If the communication fails, a Hard Reset results. For Dual-Role Power Ports the Device Policy Manager manages the functionality of both a Source and a Sink. In addition, it is able to manage the Power Role Swap process between the two. In terms of power management this Page 418 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 could mean that a Port which is initially consuming power as a Sink is able to become a power resource as a Source. Conversely, Attached Sources might request that power be provided to them. The functionality within the Device Policy Manager (and to a certain extent the Policy Engine) is scalable depending on the complexity of the device, including the number of different power supply Capabilities and the number of different features supported for example System Policy Manager interface or Capabilities Mismatch, and the number of ports being managed. Within these parameters it is possible to implement devices from very simple power supplies to more complex power supplies or devices such as USB Hubs or Hard Drives. Within multi-Port devices it is also permitted to have a combination of USB Power Delivery and non-USB Power Delivery ports which Should all be managed by the Device Policy Manager. As noted in Section 2.6, "Architectural Overview" the logical architecture used in the PD specification will vary depending on the implementation. This means that different implementations of the Device Policy Manager might be relatively small or large depending on the complexity of the device, as indicated above. It is also possible to allocate different responsibilities between the Policy Engine and the Device Policy Manager, which will lead to different types of architectures and interfaces. The Device Policy Manager is responsible for the following:  Maintaining the Local Policy for the device.  For a Source, monitoring the present Capabilities and triggering notifications of the change.  For a Sink, evaluating and responding to Capabilities related requests from the Policy Engine for a given Port.  Control of the Source/Sink in the device.  Control of the USB-C® Port Control module for each Port.  Interface to the Policy Engine for a given Port. The Device Policy Manager is responsible for the following Optional features when implemented:  Communications with the System Policy over USB.  For Sources with multiple ports monitoring and balancing power requirements across these ports.  Monitoring of batteries and AC power supplies.  Managing Modes in its Port Partner and Cable Plug(s). 8.2.1 Capabilities The Device Policy Manager in a Provider Shall know the power supplies available in the device and their Capabilities. In addition, it Shall be aware of any other PD sources of power such as batteries and AC inputs. The available power sources and existing demands on the device Shall be taken into account when presenting Capabilities to a Sink. The Device Policy Manager in a Consumer Shall know the requirements of the Sink and use this to evaluate the Capabilities offered by a Source. It Shall be aware of its own power sources e.g., Batteries or AC supplies where these have a bearing on its operation as a Sink. The Device Policy Manager in a Dual-Role Power Device Shall combine the above Capabilities and Shall also be able to present the dual-role nature of the device to an Attached PD Capable device. 8.2.2 System Policy A given PD Capable device might have no USB capability, or PD might have been added to a USB device in such a way that PD is not integrated with USB. In these two cases there Shall be no requirement for the Device Policy Manager to interact with the USB interface of the device. The following requirements Shall only apply to PD devices that expose PD functionality over USB. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 419 The Device Policy Manager Shall communicate over USB with the System Policy Manager according to the requirements detailed in [UCSI]. Whenever requested the Device Policy Manager Shall implement a Local Policy according to that requested by the System Policy Manager. For example, the System Policy Manager might request that a Battery powered Device temporarily stops charging so that there is sufficient power for an HDD to spin up. Note: Due to timing constraints, a PD Capable device Shall be able to respond autonomously to all time-critical PD related requests. 8.2.3 Control of Source/Sink The Device Policy Manager for a Provider Shall manage the power supply for each PD Source Port and Shall know at any given time what the Negotiated power is. It Shall request transitions of the supply and inform the Policy Engine whenever a transition completes. The Device Policy Manager for a Consumer Shall manage the Sink for each PD Sink Port and Shall know at any given time what the Negotiated power is. The Device Policy Manager for a Dual-Role Power Device Shall manage the transition between Source/Sink Power Roles for each PD Dual-Role Power Port and Shall know at any given time what Power Role the Port is in. 8.2.4 Cable Detection 8.2.4.1 Device Policy Manager in a Provider The Device Policy Manager in the Provider Shall control the USB-C® Port Control module and Shall be able to use the USB-C® Port Control module to determine the Attachment status. Note: It might be necessary for the Device Policy Manager to also initiate additional discovery using the Discov- er Identity Command in order to determine the full Capabilities of the cabling (see Section 6.4.4.3.1, "Dis- cover Identity"). 8.2.4.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer controls the USB-C® Port Control module and Shall be able to use the USB- C® Port Control module to determine the Attachment status. 8.2.4.3 Device Policy Manager in a Consumer/Provider The Device Policy Manager in a Consumer/Provider inherits characteristics of Consumers and Providers and Shall control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Attachment of a USB Power Delivery Provider/Consumer which supports Dead Battery back-powering.  Presence of VBUS. 8.2.4.4 Device Policy Manager in a Provider/Consumer The Device Policy Manager in a Provider/Consumer inherits characteristics of Consumers and Providers and May control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Presence of VBUS. Page 420 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.2.5 Managing Power Requirements It is the responsibility of the Device Policy Manager in a Provider to be aware of the power requirements of all devices connected to its Source Ports. This includes being aware of any reserve power that might be required by devices in the future and ensuring that power is shared optimally amongst Attached PD Capable devices. This is a key function of the Device Policy Manager; whose implementation is critical to ensuring that all PD Capable devices get the power they require in a timely fashion in order to facilitate smooth operation. This is balanced by the fact that the Device Policy Manager is responsible for managing the sources of power that are, by definition, finite. The Consumer's Device Policy Manager Shall ensure that it takes no more power than is required to perform its functions and when its requirements change, it Should make a new Request. The Provider, after satisfying the Request, Should reclaim any unused power to ensure that it can meet total power requirements of Attached Sinks on at least one Port. Note: It is expected that a future design guide will provide additional guidance. 8.2.5.1 Managing the Power Reserve There might be some products where a Device has certain functionality at one power level and a greater functionality at another, for example a Printer/Scanner that operates only as a printer with one power level and as a scanner if it can get more power. While the visibility of the linkage between power and functionality might only be apparent to the USB Host; the Device Policy Manager Should provide mechanisms to manage the power requirements of such Devices. It is the Device Policy Manager's responsibility to allocate power and maintain a power reserve so as not to over- subscribe its available power resource. A Device with multiple ports such as a Hub Shall always attempt to meet the incremental demands of the Port requiring the highest incremental power from its power reserve. 8.2.5.2 Power Capability Mismatch A Capabilities Mismatch occurs when a Consumer cannot obtain required power from a Provider (or the Source is not PD Capable) and the Consumer requires such Capabilities to operate. Different actions are taken by the Device Policy Manager and the System Policy Manager in this case. 8.2.5.2.1 Local device handling of mismatch The Consumer's Device Policy Manager Shall cause a notification to be displayed to the end user that a power Capabilities Mismatch has occurred. Examples of such feedback can include:  For a simple Device an LED May be used to indicate the failure. For example, during connection the LED could be solid amber. If the connection is successful, the LED could change to green. If the connection fails, it could be red or alternately blink amber.  A more sophisticated Device with a user interface, e.g., a mobile device or monitor, Should provide no- tification through the user interface on the Device. The Provider's Device Policy Manager May cause a notification to be displayed to the user of the power Capabilities Mismatch. Because the Capabilities Mismatch might not cause operational failure, the Provider's Device Policy Manager Should Not display a notification to the user if the power offered to the Sink meets or exceeds the SPR Sink Minimum PDP/ EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). If a notification is displayed, it Should Not be shown as an error unless the power offered to the Sink is less than the SPR Sink Minimum PDP/EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message. 8.2.5.2.2 Device Policy Manager Communication with System Policy In a USB Power Delivery aware system with an active System Policy Manager (see Section 8.2.2, "System Policy"), the Device Policy Manager Shall notify the System Policy Manager of the mismatch. This information Shall be passed back to the System Policy Manager using the mechanisms described in [UCSI]. The System Policy Manager Should Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 421 ensure that the user is informed of the condition. When another Port in the system could satisfy the Consumer's power requirements the user Should be directed to move the Device to the alternate Port. In order to identify a more suitable Source Port for the Consumer the System Policy Manager Shall communicate with the Device Policy Manager in order to determine the Consumer's requirements. The Device Policy Manager Shall use a Get_Sink_Cap Message (see Section 6.3.8, "Get_Sink_Cap Message") to discover which power levels can be utilized by the Consumer. 8.2.6 Use of "Unconstrained Power" bit with Batteries and AC supplies The Device Policy Manager in a Provider or Consumer May monitor the status of any variable sources of power that could have an impact on its Capabilities as a Source such as Batteries and AC supplies and reflect this in the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") provided as part of the Source_Capabilities or Sink_Capabilities Message (see Section 6.4.1, "Capabilities Message"). When monitored, and a USB interface is supported, the External Power status (see [UCSI]) and the Battery state (see Section 9.4.1, "GetBatteryStatus") Shall also be reported to the System Policy Manager using the USB interface. 8.2.6.1 AC Supplies The Unconstrained Power bit provided by Sources and Sinks (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") notifies a connected device that it is acceptable to use the Advertised power for charging as well as for what is needed for normal operation. A device that sets the Unconstrained Power bit has either an external source of power that is sufficient to adequately power the system while charging external devices or expects to charge external devices as a primary state of function (such as a battery pack). In the case of the external power source, the power can either be from an AC Supply directly connected to the device or from an AC Supply connected to an Attached device, which is also getting unconstrained power from its power supply. The Unconstrained Power bit is in this way communicated through a PD system indicating that the origin of the power is from a single or multiple AC supplies, from a battery bank, or similar:  If the "Unconstrained Power" bit is set, then that power is originally sourced from an AC Supply.  Devices capable of consuming on multiple ports can only claim that they have "Unconstrained Power" for the power Advertised as a Provider Port if there is unconstrained power beyond that needed for nor- mal operation coming from external supplies, (e.g., multiple AC supplies).  This concept applies as the power is routed through multiple Provider and Consumer tiers, so, as an ex- ample. Power provided out of a monitor that is connected to a monitor that gets power from an AC Sup- ply, will claim it has "Unconstrained Power" even though it is not directly connected to the AC Supply. An example use case is a Tablet computer that is used with two USB A/V displays that are daisy chained (see Figure 8.1, "Example of daisy chained displays"). The tablet and 1st display are not externally powered, (meaning, they have no source of power outside of USB PD). The 2nd display has an external supply Attached which could either be a USB PD based supply or some other form of external supply. When the displays are connected as shown, the power adapter Attached to the 2nd display is able to power both the 1st display and the tablet. In this case the 2nd display will indicate the presence of a sufficiently sized Charger to the 1st display, by setting its "Unconstrained Power" bit. The 1st display will then in turn assess and indicate the presence of the extra power to the tablet by setting its "Unconstrained Power" bit. Power is transmitted through the system to all devices, provided that there is sufficient power available from the external supply. Page 422 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.1 Example of daisy chained displays Another example use case is a laptop computer that is Attached to both an external supply and a Tablet computer. In this situation, if the external supply is large enough to power the laptop in its normal state as well as charge an external device, the laptop would set its "Unconstrained Power" bit and the tablet will allow itself to charge at its peak rate. If the external supply is small, however, and would not prevent the laptop from discharging if maximal power is drawn by the external device, the laptop would not set its "Unconstrained Power" bit, and the tablet can choose to draw less than what is offered. This amount could be just enough to prevent the tablet from discharging, or none at all. Alternatively, if the tablet determines that the laptop has significantly larger battery with more charge than the tablet has, the tablet can still choose to charge itself, although possibly not at the maximal rate. In this way, Sinks that do not receive the Unconstrained Power bit from the connected Source can still choose to charge their batteries, or charge at a reduced rate, if their policy determines that the impact to the Source is minimal -- such as in the case of a phone with a small battery charging from a laptop with a large battery. These policies can be decided via further USB PD communication. 8.2.6.2 Battery Supplies When monitored, and a USB interface is supported, the Battery state Shall be reported to the System Policy Manager using the USB interface. If the device is Battery-powered but is in a state that is primarily for charging external devices, the device is considered to be an unconstrained source of power and thus Should set the "Unconstrained Power" bit. A simplified algorithm is detailed below to ensure that Battery powered devices will get charge from non-Battery powered devices when possible, and also to ensure that devices do not constantly Power Role Swap back and forth. When two devices are connected that do not have Unconstrained Power, they Should define their own policies so as to prevent constant Power Role Swapping. This algorithm uses the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power"), thus the decisions are based on the availability and sufficiency of an external supply, not the full Capabilities of a system or device or product. Recommendations:  Provider/Consumers using large external sources ("Unconstrained Power" bit set) Should always deny Power Role Swap requests from Consumer/Providers not using external sources ("Unconstrained Pow- er" bit cleared). AC Tablet Display 1 Display 2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 423  Provider/Consumers not using large external sources ("Unconstrained Powered" bit cleared) Should al- ways accept a Power Role Swap request from a Consumer/Provider using large external power sources ("Unconstrained Power" bit set) unless the requester is not able to provide the requirements of the present Provider/Consumer. 8.2.7 Interface to the Policy Engine The Device Policy Manager Shall maintain an interface to the Policy Engine for each Port in the device. 8.2.7.1 Device Policy Manager in a Provider The Device Policy Manager in a Provider Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/ device Attachment status for a given cable.  Inform the Policy Engine whenever the Source Capabilities available for a Port change.  Evaluate requests from an Attached Consumer and provide responses to the Policy Engine.  Respond to requests for power supply transitions from the Policy Engine.  Indication to Policy Engine when power supply transitions are complete.  Maintain a power reserve for devices operating on a Port at less than maximum power. 8.2.7.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/device Attachment status.  Inform the Policy Engine whenever the power requirements for a Port change.  Evaluate Source Capabilities and provide suitable responses:  Request from offered Capabilities.  Indicate whether additional power is required.  Respond to requests for Sink transitions from the Policy Engine. 8.2.7.3 Device Policy Manager in a Dual-Role Power Device The Device Policy Manager in a Dual-Role Power Device Shall provide the following functions to the Policy Engine:  Provider Device Policy Manager  Consumer Device Policy Manager  Interface for the Policy Engine to request power supply transitions from Source to Sink and vice versa.  Indications to Policy Engine during Power Role Swap transitions. 8.2.7.4 Device Policy Manager in a Dual-Role Power Device Dead Bat- tery handling The Device Policy Manager in a Dual-Role Power Device with a Dead Battery Should:  Switch Ports to Sink-only or Sink DFP operation to obtain power from the next Attached Source.  Use VBUS from the Attached Source to power the USB Power Delivery communications as well as charging to enable the Negotiation of higher input power. Page 424 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3 Policy Engine 8.3.1 Introduction There is one Policy Engine instance per Port that interacts with the Device Policy Manager in order to implement the present Local Policy for that particular Port. This section includes:  AMSs for various operations.  State diagrams covering operation of Sources, Sinks and Cable Plugs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 425 8.3.2 Atomic Message Sequence Diagrams 8.3.2.1 Introduction The Policy Engine drives the Atomic Message Sequences (AMS) and responses based on both the expected AMSs and the present Local Policy. An AMS Shall be defined as a Message sequence that starts and/or ends in either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states (see Section 8.3.3.2, "Policy Engine Source Port State Diagram", Section 8.3.3.3, "Policy Engine Sink Port State Diagram" and Section 8.3.3.25, "Cable Plug Specific State Diagrams"). In addition, the Cable Plug discovery sequence specified in Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram" Shall be defined as an AMS. The Source and Sink indicate to the Protocol Layer when an AMS starts and ends on entry to/exit from PE_SRC_Ready or PE_SNK_Ready (see Section 8.3.3.2, "Policy Engine Source Port State Diagram" and Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). An AMS Shall be considered to have been started by the Initiator when the protocol engine signals the Policy Engine that transmission is a success (the GoodCRC Message has been received in response to the initial Message). For the receiving Port the AMS Shall be considered to have started when the initial Message has arrived. An AMS Shall be considered to have ended:  When the Protocol Layer signals the Policy Engine that transmission of the final Message in the AMS is a success and for the opposite Port when the final Message has been received.  A Soft_Reset Message, Hard Reset Signaling for SOP’ or SOP’’ or Cable Reset Signaling has been sent or received. Section 8.3.2.1.3, "Atomic Message Sequences" gives details of these AMS's. This section contains sequence diagrams that highlight some of the more interesting transactions. It is by no means a complete summary of all possible combinations but is Informative in nature. Page 426 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.1 Basic Message Exchange Figure 8.2, "Basic Message Exchange (Successful)" below illustrates how a Message is sent. Table 8.1, "Basic Message Flow" details the steps in the flow. Note that the sender might be either a Source or Sink while the receiver might be either a Sink or Source. The basic Message sequence is the same. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. Figure 8.2 Basic Message Exchange (Successful) Table 8.1 Basic Message Flow Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 7 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Protocol Layer checks and increments the MessageIDCounter and stops CRCReceiveTimer. 9 Protocol Layer informs the Policy Engine that the Message was successfully sent. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 427 8.3.2.1.2 Errors in Basic Message flow There are various points during the Message flow where failures in communication or other issues can occur. Figure 8.3, "Basic Message flow indicating possible errors" is an annotated version of Figure 8.2, "Basic Message Exchange (Successful)" indicating at which point issues can occur. Table 8.2, "Potential issues in Basic Message Flow" details the steps in the flow. Figure 8.3 Basic Message flow indicating possible errors Table 8.2 Potential issues in Basic Message Flow Point Possible issues A 1) There is an incoming Message on the channel meaning that the PHY Layer is unable to send. In this case the outgoing Message is removed from the queue and the incoming Message processed. 2) Due to some sort of noise on the line it is not possible to transmit. In this case the outgoing Message is Discarded by the PHY Layer. Retransmission is via the Protocol Layer’s normal mechanism. B 1) Message does not arrive at the PHY Layer due to noise on the channel. 2) Message arrives but has been corrupted and has a bad CRC. There is no Message to pass up to the Protocol Layer on the receiver which means a GoodCRC Message is not sent. This leads to a CRCReceiveTimer timeout in the Message Sender. C 1) MessageID of received Message matches stored MessageID so this is a retry. Message is not passed up to the Policy Engine. D 1) Policy Engine receives a known Message that it was not expecting. 2) Policy Engine receives an Unrecognized Message. These cases are errors in the protocol which could lead to the generation of a Soft_Reset Message. E Same as point A but at the Message Receiver side. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver • Message currently being received • Channel unavailable • Message does not arrive • Message has bad CRC • Message is a retry • Message is unexpected • Message is unknown • Message currently being received • Channel unavailable • GoodCRC does not arrive • GoodCRC has a bad CRC • GoodCRC has the wrong MessageID • Response is not GoodCRC A B C D E F G Page 428 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.4, "Basic Message Flow with Bad followed by a Retry" illustrates one of these cases; the basic Message flow with a retry due to a bad CRC at the Message Receiver. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. The Protocol Layer is responsible for retries on a “'n' strikes and you are out" basis (nRetryCount). Table 8.3, "Basic Message Flow with CRC failure" details the steps in the flow. Figure 8.4 Basic Message Flow with Bad followed by a Retry F 1) GoodCRC Message response does not arrive at the Message Sender side due to the noise on the channel. 2) GoodCRC Message response arrives but has a bad CRC. A GoodCRC Message is not received by the Message Sender’s Protocol Layer. This leads to a CRCReceiveTimer timeout in the Message Sender. G 1) GoodCRC Message is received but does contain the same MessageID as the transmitted Message. 2) A Message is received but it is not a GoodCRC Message (similar case to that of an unexpected or unknown Message but this time detected in the Protocol Layer). Both of these issues indicate errors in receiving an expected GoodCRC Message which will lead to a CRCReceiveTimer timeout in the Protocol Layer and a subsequent retry (except for communications with Cable Plugs). Table 8.2 Potential issues in Basic Message Flow Point Possible issues : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine 4: Message 5: Message + CRC 6: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 7: Message received Consume message 8: GoodCRC 9: GoodCRC + CRC 10: GoodCRC Check and increment MessageIDCounter Reset RetryCounter Stop CRCReceiveTimer 11: Message sent 1: Send message 2: Message 3: Message + CRC Start CRCReceiveTimer CRCReceiveTimer expires Retry and increment RetryCounter Message is not received or CRC is bad so message is not passed to the protocol layer Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 429 Table 8.3 Basic Message Flow with CRC failure Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives no Message or a Message with an incorrect CRC. Nothing is passed to Protocol Layer. 4 Since no response is received, the CRCReceiveTimer will expire and trigger the first retry by the Protocol Layer. The RetryCounter is incremented. Protocol Layer passes the Message to the PHY Layer. 5 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 6 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 7 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 8 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 9 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 10 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 11 Protocol Layer verifies the MessageID, stops CRCReceiveTimer and resets the RetryCounter. Protocol Layer informs the Policy Engine that the Message was successfully sent. Page 430 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3 Atomic Message Sequences The types of Atomic Message Sequences (AMS) are listed in Table 8.4, "Atomic Message Sequences". The following tables list sequences of either Messages or combinations of Messages and one or more embedded AMSes which are Non-interruptible. Where there is an embedded AMS the entire Message sequence is treated as an AMS and the Rp value used for Collision Avoidance (see Section 5.7, "Collision Avoidance") Shall only be changed on leaving or entering the ready state at the beginning or end of the entire Message sequence, and not at the start or end of the embedded AMS. Note: An AMS is has not started until the first Message in the sequence has been successfully sent (i.e., a GoodCRC Message has been received acknowledging the Message). Table 8.31, "AMS: Hard Reset" details a Hard Reset (which is Signaling not an AMS) followed by an SPR Contract Negotiation AMS which Shall be treated as Non-interruptible. Table 8.4 Atomic Message Sequences Type of AMS Table Reference Section Reference Power Negotiation (SPR) Table 8.5, "AMS: Power Negotiation (SPR)" Section 8.3.2.2.1 Power Negotiation (EPR) Table 8.6, "AMS: Power Negotiation (EPR)" Section 8.3.2.2.2 Unsupported Message Table 8.7, "AMS: Unsupported Message" Section 8.3.2.3 Soft Reset Table 8.8, "AMS: Soft Reset" Section 8.3.2.4 Data Reset Table 8.9, "AMS: Data Reset" Section 8.3.2.5 Hard Reset Table 8.31, "AMS: Hard Reset" Section 8.3.2.6 Power Role Swap Table 8.10, "AMS: Power Role Swap" Section 8.3.2.7 Fast Role Swap Table 8.11, "AMS: Fast Role Swap" Section 8.3.2.8 Data Role Swap Table 8.12, "AMS: Data Role Swap" Section 8.3.2.9 VCONN Swap Table 8.13, "AMS: VCONN Swap" Section 8.3.2.10 Alert Table 8.14, "AMS: Alert" Section 8.3.2.11.1 Status Table 8.15, "AMS: Status" Section 8.3.2.11.2 Source Capabilities/ Sink Capabilities (SPR) Table 8.16, "AMS: Source/Sink Capabilities (SPR)" Section 8.3.2.11.3.1 Source Capabilities/ Sink Capabilities (EPR) Table 8.17, "AMS: Source/Sink Capabilities (EPR)" Section 8.3.2.11.3.2 Extended Capabilities Table 8.18, "AMS: Extended Capabilities" Section 8.3.2.11.4 Battery Capabilities and Status Table 8.19, "AMS: Battery Capabilities" Section 8.3.2.11.5 Manufacturer Information Table 8.20, "AMS: Manufacturer Information" Section 8.3.2.11.6 Country Codes Table 8.21, "AMS: Country Codes" Section 8.3.2.11.7 Country Information Table 8.22, "AMS: Country Information" Section 8.3.2.11.8 Revision Information Table 8.23, "AMS: Revision Information" Section 8.3.2.11.9 Source Information Table 8.24, "AMS: Source Information" Section 8.3.2.11.10 Security Table 8.25, "AMS: Security" Section 8.3.2.12 Firmware Update Table 8.26, "AMS: Firmware Update" Section 8.3.2.13 Structured VDM Table 8.27, "AMS: Structured VDM" Section 8.3.2.14 Built-In Self-Test (BIST) Table 8.28, "AMS: Built-In Self-Test (BIST)" Section 8.3.2.15 Enter USB Table 8.29, "AMS: Enter USB" Section 8.3.2.16 Unstructured VDM Table 8.30, "AMS: Unstructured VDM" Section 8.3.2.17 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 431 8.3.2.1.3.1 AMS: Power Negotiation (SPR) Table 8.5 AMS: Power Negotiation (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref SPR Explicit Contract Negotiation (Accept) 1. Source_Capabilities Message 2. Request Message 3. Accept Message 4. PS_RDY Message Started by Source, SPR Mode Section 8.3.2.2.1.1.1 Section 8.3.3.2, Section 8.3.3.3 SPR Explicit Contract Negotiation (Reject) 1. Source_Capabilities Message 2. Request Message 3. Reject Message Section 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Wait) 1. Source_Capabilities Message 2. Request Message 3. Wait Message Section 8.3.2.2.1.1.3 SPR PPS Keep Alive 1. Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, SPR Mode Section 8.3.2.2.1.2 Section 8.3.3.3 SPR Sink Makes Request (Accept) 1. Request Message 2. Accept Message 3. PS_RDY Message Section 8.3.2.2.1.3.1 Section 8.3.3.2, Section 8.3.3.3 SPR Sink Makes Request (Reject) 1. Request Message 2. Reject Message Section 8.3.2.2.1.3.2 SPR Sink Makes Request (Wait) 1. Request Message 2. Wait Message Section 8.3.2.2.1.3.3 Page 432 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.2 AMS: Power Negotiation (EPR) Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Entering EPR Mode (Success) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS (Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Succeeded) Message 6. EPR Explicit Contract Negotiation AMS Started by Sink, SPR Mode Section 8.3.2.2.2.1, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3, Section 8.3.2.2.2.4 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1, Section 8.3.3.2, Section 8.3.3.3 Entering EPR Mode (Failure due to non-EPR Cable) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS(Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.2, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1 Entering EPR Mode (Failure of VCONN Swap) 1. EPR_Mode (Enter) Message. 2. EPR_Mode (Enter Acknowledge) Message. 3. VCONN Source Swap, initiated by non- VCONN Source (Reject) AMS(Optional). 4. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.3, Section 8.3.2.10.1, Section 8.3.2.10.2 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 433 EPR Explicit Contract Negotiation (Accept) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Accept Message 4. PS_RDY Message Started by Source, EPR Mode Section 8.3.2.2.2.2.1 Section 8.3.3.2, Section 8.3.3.3 EPR Explicit Contract Negotiation (Reject) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Reject Message Section 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Wait) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Wait Message Section 8.3.2.2.2.2.3 EPR Keep Alive 1. EPR_KeepAlive Message 2. EPR_KeepAlive_Ack Message Started by Sink, EPR Mode Section 8.3.2.2.2.3 Exiting EPR Mode (Sink Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Sink, EPR Mode Section 8.3.2.2.2.4.1, Section 8.3.2.2.1.1 Section 8.3.3.25.3, Section 8.3.3.25.4, Section 8.3.3.2, Section 8.3.3.3 Exiting EPR Mode (Source Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Source, EPR Mode Section 8.3.2.2.2.4.2, Section 8.3.2.2.1.1 EPR Sink Makes Request (Accept) 1. EPR_Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.1 Section 8.3.3.2, Section 8.3.3.3 EPR Sink Makes Request (Reject) 1. EPR_Request Message 2. Reject Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.2 EPR Sink Makes Request (Wait) 1. EPR_Request Message 2. Wait Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.3 Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Page 434 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.3 AMS: Unsupported Message 8.3.2.1.3.4 AMS: Soft Reset 8.3.2.1.3.5 AMS: Data Reset Table 8.7 AMS: Unsupported Message AMS Message Sequence Conditions AMS Ref State Machine Ref Unsupported Message 1. Any Message which is not supported by the Source or Sink 2. Not_Supported Message Started by Source or Sink Section 8.3.2.3 Section 8.3.3.6.2 Table 8.8 AMS: Soft Reset AMS Message Sequence Conditions AMS Ref State Machine Ref Soft Reset 1. Soft_Reset Message 2. Accept Message 3. In SPR Mode: SPR Explicit Contract Negotiation AMS 4. or in EPR Mode: EPR Explicit Contract Negotiation AMS. Started by Source or Sink Section 8.3.2.4, Section 8.3.2.2.1.1, Section 8.3.2.2.1.1, Section 8.3.2.2.2.2 Section 8.3.3.4.1, Section 8.3.3.4.2, Section 8.3.3.25.2.1, Section 8.3.3.25.2.3, Section 8.3.3.25.2.4, Section 8.3.3.2, Section 8.3.3.3 Table 8.9 AMS: Data Reset AMS Message Sequence Conditions AMS Ref State Machine Ref DFP Initiated Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.1 Section 8.3.3.5.1, Section 8.3.3.5.2 DFP Receives Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.2 DFP Initiated Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.3 DFP Receives Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 435 8.3.2.1.3.6 AMS: Power Role Swap 8.3.2.1.3.7 AMS: Fast Role Swap Table 8.10 AMS: Power Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.7.1.1, Section 8.3.2.2.1.1 Section 8.3.3.19.3, Section 8.3.3.19.4, Section 8.3.3.2, Section 8.3.3.3 Source Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.1.2 Source Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.1.1 Sink Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.7.2.1, Section 8.3.2.2.1.1 Sink Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.2.2 Sink Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.2.3 Table 8.11 AMS: Fast Role Swap AMS Message Sequence Conditio ns AMS Ref State Machine Ref Fast Role Swap 1. FR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.8, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3, Section 8.3.3.19.5, Section 8.3.3.19.6 Page 436 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.8 AMS: Data Role Swap Table 8.12 AMS: Data Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Data Role Swap, Initiated by UFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.1.1 Section 8.3.3.19.1, Section 8.3.3.19.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.2.3 Data Role Swap, Initiated by DFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.4.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 437 8.3.2.1.3.9 AMS: VCONN Swap 8.3.2.1.3.10 AMS: Alert Table 8.13 AMS: VCONN Swap AMS Message Sequence Conditions AMS Ref State Machine Ref VCONN Source Swap, initiated by VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by VCONN Source Section 8.3.2.10.1.1 Section 8.3.3.20 VCONN Source Swap, initiated by VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.1.3 VCONN Source Swap, initiated by non- VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by non-VCONN Source Section 8.3.2.10.2.1 VCONN Source Swap, initiated by non- VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.2.2 VCONN Source Swap, initiated by non- VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.2.3 Table 8.14 AMS: Alert AMS Message Sequence Conditions AMS Ref AMS Ref Source sends Alert to a Sink (SenderResponseTi mer Timeout) 1. Alert Message Started by Source Section 8.3.2.11.1.1 Section 8.3.3.7.1, Section 8.3.3.7.2 Source sends Alert to a Sink (Get_Status Message) 1. Alert Message 2. Sink Gets Source Status AMS Sink sends Alert to a Source (SenderResponseTi mer Timeout) 1. Alert Message Started by Sink Section 8.3.2.11.1.2 Section 8.3.3.7.3, Section 8.3.3.7.4 Sink sends Alert to a Source (Get_Status Message) 1. Alert Message 2. Source Gets Sink Status AMS Page 438 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.11 AMS: Status 8.3.2.1.3.12 AMS: Source/Sink Capabilities (SPR) Table 8.15 AMS: Status AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Status 1. Get_Status Message 2. Status Message Started by Sink Started by Source Section 8.3.2.11.2.1, Section 8.3.2.11.2.2 Section 8.3.3.10.1, Section 8.3.3.10.2 Source Gets Sink Status 1. Get_Status Message 2. Status Message VCONN Source Gets Cable Plug Status 1. Get_Status Message 2. Status Message Started by VCONN Source Started by Sink Section 8.3.2.11.2.3, Section 8.3.2.11.2.4 Sink Gets Source PPS Status 1. Get_PPS_Status Message 2. PPS_Status Message Section 8.3.3.10.3, Section 8.3.3.10.4 Table 8.16 AMS: Source/Sink Capabilities (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Capabilities (EPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Sink Section 8.3.2.11.3.1.1, Section 8.3.2.2.1.3.1, Section 8.3.2.2.1.3.2, Section 8.3.2.2.1.3.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets Source Capabilities (Accept in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Accept) AMS Sink Gets Source Capabilities (Reject in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Reject) AMS Sink Gets Source Capabilities (Wait in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Source Section 8.3.2.11.3.1.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink Capabilities 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Source Section 8.3.2.11.3.1.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.1.4 Section 8.3.3.19.9, Section 8.3.3.19.8 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 439 8.3.2.1.3.13 AMS: Source/Sink Capabilities (EPR) Table 8.17 AMS: Source/Sink Capabilities (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets EPR Source Capabilities (SPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Sink Section 8.3.2.11.3.2.1, Section 8.3.2.2.2.5.1, Section 8.3.2.2.2.5.2, Section 8.3.2.2.2.5.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets EPR Source Capabilities (Accept in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Accept) AMS Sink Gets EPR Source Capabilities (Reject in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Reject) AMS Sink Gets EPR Source Capabilities (Wait in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power EPR Sink 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Source Section 8.3.2.11.3.2.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink EPR Capabilities 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Source Section 8.3.2.11.3.2.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink EPR Capabilities from a Dual-Role Power Source 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.2.4 Section 8.3.3.19.8, Section 8.3.3.19.9 Page 440 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.14 AMS: Extended Capabilities 8.3.2.1.3.15 AMS: Battery Capabilities Table 8.18 AMS: Extended Capabilities AMS Interruptible Message Sequence Conditions AMS Ref Sink Gets Source Extended Capabilities 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.4.1 Section 8.3.3.8.1, Section 8.3.3.8.2 Dual-Role Power Source Gets Source Extended Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.4.2 Section 8.3.3.19.11, Section 8.3.3.19.12 Source Gets Sink Extended Capabilities 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Source Section 8.3.2.11.4.3 Section 8.3.3.8.3, Section 8.3.3.8.4 Dual-Role Power Sink Gets Sink Extended Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Sink Section 8.3.2.11.4.4 Section 8.3.3.19.13, Section 8.3.3.19.14 Table 8.19 AMS: Battery Capabilities AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Sink Section 8.3.2.11.5.1 Section 8.3.3.11.1, Section 8.3.3.11.2 Source Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Source Section 8.3.2.11.5.2 Sink Gets Battery Status 1. Get_Battery_Status Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.3 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Battery Status 1. Get_Battery_Cap Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 441 8.3.2.1.3.16 AMS: Manufacturer Information 8.3.2.1.3.17 AMS: Country Codes 8.3.2.1.3.18 AMS: Country Information Table 8.20 AMS: Manufacturer Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Port Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.1 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Port Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.2 Source Gets Battery Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.3 Sink Gets Battery Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.4 VCONN Source Gets Manufacturer Information from a Cable Plug 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by VCONN Source Section 8.3.2.11.6.5 Table 8.21 AMS: Country Codes AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Codes from a Sink 1. Get_Country_Codes Message 2. Country_Codes Message Started by Source Section 8.3.2.11.7.1 Section 8.3.3.14.1, Section 8.3.3.14.2 Sink Gets Country Codes from a Source 1. Get_Country_Codes Message 2. Country_Codes Message Started by Sink Section 8.3.2.11.7.2 VCONN Source Gets Country Codes from a Cable Plug 1. Get_Country_Codes Message 2. Country_Codes Message Started by VCONN Source Section 8.3.2.11.7.3 Table 8.22 AMS: Country Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Information from a Sink 1. Get_Country_Info Message 2. Country_Info Message Started by Source Section 8.3.2.11.8.1 Section 8.3.3.14.3, Section 8.3.3.14.4 Sink Gets Country Information from a Source 1. Get_Country_Info Message 2. Country_Info Message Started by Sink Section 8.3.2.11.8.2 VCONN Source Gets Country Information from a Cable Plug 1. Get_Country_Info Message 2. Country_Info Message Started by VCONN Source Section 8.3.2.11.8.3 Page 442 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.19 AMS: Revision Information 8.3.2.1.3.20 AMS: Source Information 8.3.2.1.3.21 AMS: Security Table 8.23 AMS: Revision Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Revision Information from a Sink 1. Get_Revision Message 2. Revision Message Started by Source Section 8.3.2.11.9.1 Section 8.3.3.15.1, Section 8.3.3.15.2 Sink Gets Revision Information from a Source 1. Get_Revision Message 2. Revision Message Started by Sink Section 8.3.2.11.9.2 VCONN Source Gets Revision Information from a Cable Plug 1. Get_Revision Message 2. Revision Message Started by VCONN Source Section 8.3.2.11.9.1 Table 8.24 AMS: Source Information AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Information 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.10.1 Section 8.3.3.9.1, Section 8.3.3.9.2 Dual-Role Power Source Gets Source Information from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.10.2 Section 8.3.3.19.15, Section 8.3.3.19.16 Table 8.25 AMS: Security AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests security exchange with Sink 1. Security_Request Message Started by Source Section 8.3.2.12.1 Section 8.3.3.17.1, Section 8.3.3.17.2, Section 8.3.3.17.3 Sink requests security exchange with Source 1. Security_Request Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Request Message Started by VCONN Source Section 8.3.2.12.3 Source responds to security exchange with Sink 1. Security_Response Message Started by Source Section 8.3.2.12.1 Sink responds to security exchange with Source 1. Security_Response Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Response Message Started by VCONN Source Section 8.3.2.12.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 443 8.3.2.1.3.22 AMS: Firmware Update Table 8.26 AMS: Firmware Update AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests firmware update exchange with Sink 1. Firmware_Update_Request Message Started by Source Section 8.3.2.13.1 Section 8.3.3.18.1, Section 8.3.3.18.2, Section 8.3.3.18.3 Sink requests firmware update exchange with Source 1. Firmware_Update_Request Message Started by Sink Section 8.3.2.13.2 VCONN Source requests firmware update exchange with Cable Plug 1. Firmware_Update_Request Message Started by VCONN Source Section 8.3.2.13.3 Source responds to firmware update exchange with Sink 1. Firmware_Update_Response Message Started by Source Section 8.3.2.13.1 Sink responds to firmware update exchange with Source 1. Firmware_Update_Response Message Started by Sink Section 8.3.2.13.2 VCONN Source responds to firmware update exchange with Cable Plug 1. Firmware_Update_Response Message Started by VCONN Source Section 8.3.2.13.3 Page 444 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.23 AMS: Structured VDM Table 8.27 AMS: Structured VDM AMS Message Sequence Conditions AMS Ref State Machine Ref Initiator to Responder Discover Identity (ACK) 1. Discover Identity REQ Command 2. Discover Identity ACK Command Started by Initiator Section 8.3.2.14.1.1 Section 8.3.3.21.1, Section 8.3.3.22.1 Initiator to Responder Discover Identity (NAK) 1. Discover Identity REQ Command 2. Discover Identity NAK Command Section 8.3.2.14.1.2 Initiator to Responder Discover Identity (BUSY) 1. Discover Identity REQ Command 2. Discover Identity BUSY Command Section 8.3.2.14.1.3 Initiator to Responder Discover SVIDs (ACK) 1. Discover SVIDs REQ Command 2. Discover SVIDs ACK Command Section 8.3.2.14.2.1 Section 8.3.3.21.2, Section 8.3.3.22.2 Initiator to Responder Discover SVIDs (NAK) 1. Discover SVIDs REQ Command 2. Discover SVIDs NAK Command Section 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (BUSY) 1. Discover SVIDs REQ Command 2. Discover SVIDs BUSY Command Section 8.3.2.14.2.3 Initiator to Responder Discover Modes (ACK) 1. Discover Modes REQ Command 2. Discover Modes ACK Command Section 8.3.2.14.3.1 Section 8.3.3.21.3, Section 8.3.3.22.3 Initiator to Responder Discover Modes (NAK) 1. Discover Modes REQ Command 2. Discover Modes NAK Command Section 8.3.2.14.3.2 Initiator to Responder Discover Modes (BUSY) 1. Discover Modes REQ Command 2. Discover Modes BUSY Command Section 8.3.2.14.3.3 DFP to UFP Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Started by DFP Section 8.3.2.14.4.1 Section 8.3.3.23.1, Section 8.3.3.24.1 DFP to UFP Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.2 Section 8.3.3.23.2, Section 8.3.3.24.2 DFP to Cable Plug Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Section 8.3.2.14.4.3 Section 8.3.3.23.1, Section 8.3.3.25.4.1 DFP to Cable Plug Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.4 Section 8.3.3.23.2, Section 8.3.3.25.4.2 Initiator to Responder Attention 1. Attention REQ Command Started by Initiator Section 8.3.2.14.4.5 Section 8.3.3.21.4, Section 8.3.3.22.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 445 8.3.2.1.3.24 AMS: Built-In Self-Test (BIST) 8.3.2.1.3.25 AMS: Enter USB 8.3.2.1.3.26 AMS: Unstructured VDM Table 8.28 AMS: Built-In Self-Test (BIST) AMS Message Sequence Conditions AMS Ref State Machine Ref BIST Carrier Mode 1. BIST (BIST Carrier Mode) Message Started by Tester Section 8.3.2.15.1 Section 8.3.3.27.1 BIST Test Data Mode 1. BIST (BIST Test Data) Message Section 8.3.2.15.2 Section 8.3.3.27.2 BIST Shared Capacity Test Mode 1. BIST (BIST Shared Test Mode Entry) Message 2. Series of Messages 3. BIST (BIST Shared Test Mode Exit) Message Section 8.3.2.15.3 Section 8.3.3.27.3 Table 8.29 AMS: Enter USB AMS Message Sequence Conditions AMS Ref State Machine Ref UFP Entering USB4® Mode (Accept) 1. Enter_USB Message 2. Accept Message Started by DFP Section 8.3.2.16.1.1 Section 8.3.3.16.1, Section 8.3.3.16.2 UFP Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.1.2 UFP Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.1.3 Cable Plug Entering USB4 Mode (Accept) 1. Enter_USB Message 2. Accept Message Section 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.2.3 Table 8.30 AMS: Unstructured VDM AMS Message Sequence AMS Ref State Machine Ref Unstructured VDM 1. Unstructured Vendor_Defined Message Section 8.3.2.17.1 VDEM 1. Vendor_Defined_Extended Message Section 8.3.2.17.2 Page 446 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.27 AMS: Hard Reset Table 8.31 AMS: Hard Reset AMS Interruptibl e Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.1, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3 Sink Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.6.2, Section 8.3.2.2.1.1 Source Initiated Hard Reset – Sink Long Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.3, Section 8.3.2.2.1.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 447 8.3.2.2 Power Negotiation 8.3.2.2.1 SPR 8.3.2.2.1.1 SPR Explicit Contract Negotiation 8.3.2.2.1.1.1 SPR Explicit Contract Negotiation (Accept) Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through 5 distinct phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  For SPR PPS operation:  the Source starts its keep alive timer.  the Sink starts its request timer to send periodic Request Messages. Page 448 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.5 Successful Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer For PPS operation start PPSRequestTimer New Power level Evaluate Capabilities Detect plug type Evaluate Request Prepare for new power Source Sink Cable Capabilities detected Plug type detected For PPS operation start PPSTimeoutTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 449 Table 8.32, "Steps for a successful Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.32 Steps for a successful Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 450 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.32 Steps for a successful Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 451 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. New Power Level Negotiated Table 8.32 Steps for a successful Power Negotiation Step Source Sink Page 452 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Reject) Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Reject Message. Figure 8.6 Rejected Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 453 Table 8.33, "Steps for a rejected Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 454 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 455 8.3.2.2.1.1.3 SPR Explicit Contract Negotiation (Wait) Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Wait Message. Figure 8.7 Wait response to Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Page 456 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.34, "Steps for a Wait response to a Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 457 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink Page 458 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.2 SPR PPS Keep Alive This is an example of SPR PPS keep alive operation during an Explicit Contract with SPR PPS as the APDO. Figure 8.8, "SPR PPS Keep Alive" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.8 SPR PPS Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer Stop PPSCommTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer Stop PPSRequestTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Send Ping if required to maintain activity Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer Start PPSRequestTimer New Power level Evaluate Request Prepare for new power Source Sink PPSRequestTimer Timeout Start PPSCommTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 459 Table 8.35, "Steps for SPR PPS Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.8, "SPR PPS Keep Alive" above. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink 1 The SinkPPSPeriodicTimer times out in the Policy Engine. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourcePPSCommTimer. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Page 460 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 27 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 461 8.3.2.2.1.3 SPR Sink Makes Request 8.3.2.2.1.3.1 SPR Sink Makes Request (Accept) This is an example of SPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.9, "SPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.9 SPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate Request Prepare for new power Source Sink Page 462 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.36, "Steps for SPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.9, "SPR Sink Makes Request (Accept)" above. Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 463 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink Page 464 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.3.2 SPR Sink Makes Request (Reject) This is an example of SPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.10, "SPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.10 SPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 465 Table 8.37, "Steps for SPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.10, "SPR Sink Makes Request (Reject)" above. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 466 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 467 8.3.2.2.1.3.3 SPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.11, "SPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.11 SPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate Request Source Sink Page 468 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.38, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.11, "SPR Sink Makes Request (Wait)" above. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 469 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 470 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2 EPR 8.3.2.2.2.1 Entering EPR Mode 8.3.2.2.2.1.1 Entering EPR Mode (Success) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process succeeds. Figure 8.12, "Entering EPR Mode (Success)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.12 Entering EPR Mode (Success) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode entered Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is EPR Capable 21: Send EPR_Mode (Enter Succeeded) 22: EPR_Mode (Enter Succeeded) 23: EPR_Mode (Enter Succeeded) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Succeeded) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Succeeded) 25: EPR_Mode (Enter Succeeded) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 471 Table 8.39, "Steps for Entering EPR Mode (Success)" below provides a detailed explanation of what happens at each labeled step in Figure 8.12, "Entering EPR Mode (Success)" above. Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter)Source_Capabilities Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 472 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source is now the VCONN Source and has determined that the Sink and the cable are EPR Capable. The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Succeeded) Message. 22 Protocol Layer creates the EPR_Mode (Enter Succeeded) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Succeeded) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Succeeded) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Succeeded) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Succeeded) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Entered Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 473 8.3.2.2.2.1.2 Entering EPR Mode (Failure due to non-EPR cable) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to the cable not being capable of EPR. Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.13 Entering EPR Mode (Failure due to non-EPR cable) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is not EPR Capable 21: Send EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) 23: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Failed) 25: EPR_Mode (Enter Failed) received Page 474 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.40, "Steps for Entering EPR Mode (Failure due to non-EPR cable)" below provides a detailed explanation of what happens at each labeled step in Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" above. Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 475 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR; cable is not EPR Capable. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 22 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source Page 476 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.1.3 Entering EPR Mode (Failure of VCONN Swap) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to a failure of the VCONN Swap process. Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.14 Entering EPR Mode (Failure of VCONN Swap) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source fails to become VCONN Source 20: Send EPR_Mode (Enter Failed) 21: EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 25: GoodCRC 26: GoodCRC + CRC 27: GoodCRC 28: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 23: EPR_Mode (Enter Failed) 24: EPR_Mode (Enter Failed) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 477 Table 8.41, "Steps for Entering EPR Mode (Failure of VCONN Swap)" below provides a detailed explanation of what happens at each labeled step in Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" above. Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 478 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". In this case the VCONN Swap process fails. 20 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 21 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 22 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 23 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 24 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 25 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 26 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 27 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 28 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 479 8.3.2.2.2.2 EPR Explicit Contract Negotiation 8.3.2.2.2.2.1 EPR Explicit Contract Negotiation (Accept) Figure 8.15, "Successful Fixed EPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  the Source starts its keep alive timer  the Sink starts its request timer to send periodic EPR_KeepAlive Messages Page 480 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.15 Successful Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer Start SinkEPRKeepAliveTimer New Power level Evaluate EPR Capabilities Evaluate EPR Request Prepare for new power Source Sink Cable EPR_Source_Capabilities detected Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 481 Table 8.42, "Steps for a successful EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.15, "Successful Fixed EPR Power Negotiation" above. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 482 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 483 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. The Policy Engine starts the SinkEPRKeepAliveTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in EPR operation the Policy Engine starts the SourceEPRKeepAliveTimer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Page 484 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Reject) Figure 8.16, "Rejected Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Reject Message. Figure 8.16 Rejected Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 485 Table 8.43, "Steps for a Rejected EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.16, "Rejected Fixed EPR Power Negotiation" above. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 486 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 487 8.3.2.2.2.2.3 EPR Explicit Contract Negotiation (Wait) Figure 8.17, "Wait response to Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Wait Message. Figure 8.17 Wait response to Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Page 488 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.44, "Steps for a Wait response to an EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.17, "Wait response to Fixed EPR Power Negotiation" above. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 489 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink Page 490 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.3 EPR Keep Alive This is an example of keep alive operation during an Explicit Contract in EPR Mode. Figure 8.18, "EPR Keep Alive"shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.18 EPR Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_KeepAlive 2: EPR_KeepAlive 3: EPR_KeepAlive + CRC 4: EPR_KeepAlive Check MessageID against local copy Store copy of MessageID 5: EPR_KeepAlive received Stop SourceEPRKeepAliveTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_KeepAlive sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send EPR_KeepAlive_Ack 11: EPR_KeepAlive_Ack 12: EPR_KeepAlive_Ack + CRC 13: EPR_KeepAlive_Ack Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: EPR_KeepAlive_Ack received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: EPR_KeepAlive_Ack sent Stop SenderResponseTimer Start SinkEPRKeepAliveTimer EPR Mode Continues Evaluate EPR_KeepAlive Source Sink SinkEPRKeepAliveTimer Timeout Stop SinkEPRKeepAliveTimer Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 491 Table 8.45, "Steps for EPR Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.18, "EPR Keep Alive" above. Table 8.45 Steps for EPR Keep Alive Step Source Sink 1 The SinkEPRKeepAliveTimer times out in the Policy Engine. The Policy Engine stops the SinkEPRKeepAliveTimer timer and tells the Protocol Layer to form an EPR_KeepAlive Message. 2 The Protocol Layer creates the EPR_KeepAlive Message and passes it to PHY Layer. The Protocol Layer. 3 PHY Layer receives the EPR_KeepAlive Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_KeepAlive Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourceEPRKeepAliveTimer. 6 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 9 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the SinkEPRKeepAliveTimer Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM to evaluate the SourceEPRKeepAliveTimer Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an EPR_KeepAlive_Ack Message. 11 The Protocol Layer forms the EPR_KeepAlive_Ack Message that is passed to the PHY Layer. 12 PHY Layer appends CRC and sends the EPR_KeepAlive_Ack Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_KeepAlive_Ack Message and compares the CRC it calculated with the one sent to verify the Message. 13 PHY Layer forwards the EPR_KeepAlive_Ack Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the SinkEPRKeepAliveTimer. Page 492 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 18 The Protocol Layer informs the Policy Engine that an EPR_KeepAlive_Ack Message was successfully sent. The Policy Engine starts the SourceEPRKeepAliveTimer. EPR Mode Continues Table 8.45 Steps for EPR Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 493 8.3.2.2.2.4 Exiting EPR Mode 8.3.2.2.2.4.1 Exiting EPR Mode (Sink Initiated) This is an example of an Exit EPR Mode operation where the Sink requests EPR Mode to be exited. Figure 8.19, "Exiting EPR Mode (Sink Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.19 Exiting EPR Mode (Sink Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Page 494 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.46, "Steps for Exiting EPR Mode (Sink Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.19, "Exiting EPR Mode (Sink Initiated)" above. Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 495 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source Page 496 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.4.2 Exiting EPR Mode (Source Initiated) This is an example of an Exit EPR Mode operation where the Source requests EPR Mode to be exited. Figure 8.20, "Exiting EPR Mode (Source Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.20 Exiting EPR Mode (Source Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 497 Table 8.47, "Steps for Exiting EPR Mode (Source Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.20, "Exiting EPR Mode (Source Initiated)" above. Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. Starts CRCReceiveTimer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Page 498 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 499 8.3.2.2.2.5 EPR Sink Makes Request 8.3.2.2.2.5.1 EPR Sink Makes Request (Accept) This is an example of EPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.21, "EPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.21 EPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate EPR_Request Prepare for new power Source Sink Page 500 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.48, "Steps for EPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.21, "EPR Sink Makes Request (Accept)" above. Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 501 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink Page 502 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.5.2 EPR Sink Makes Request (Reject) This is an example of EPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.22, "EPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.22 EPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 503 Table 8.49, "Steps for EPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.22, "EPR Sink Makes Request (Reject)" above. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 504 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 505 8.3.2.2.2.5.3 EPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.23, "EPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.23 EPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Page 506 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.50, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.23, "EPR Sink Makes Request (Wait)" above. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 507 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 508 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.3 Unsupported Message This is an example of the response to an Unsupported Message. Figure 8.24, "Unsupported message" shows the Messages as they flow across the bus and within the devices. Figure 8.24 Unsupported message : Protocol 1: Send Message : PHY : PHY : Protocol 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer 5: Message received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Message sent Start SenderResponseTimer 10: Send Not_supported 11: Not_supported 12: Not_supported + CRC 13: Not_supported 14: Not_supported received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Not_supported sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Message Initiator Message Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 509 Table 8.51, "Steps for an Unsupported Message" below provides a detailed explanation of what happens at each labeled step in Figure 8.24, "Unsupported message" above. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder 1 The Policy Engine directs the Protocol Layer to generate a Message. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Not_Supported Message. 11 Protocol Layer creates the Not_Supported Message and passes to PHY Layer. 12 PHY Layer receives the Not_Supported Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Not_Supported Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Not_Supported Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 510 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Not_Supported Message was successfully sent. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 511 8.3.2.4 Soft Reset This is an example of a Soft Reset operation. Figure 8.25, "Soft Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Soft Reset. Figure 8.25 Soft Reset : Protocol 1: Send Soft Reset : PHY : PHY : Protocol 2: Soft Reset 3: Soft Reset + CRC 4: Soft Reset Start CRCReceiveTimer 5: Soft Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Soft Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Reset Complete, Explicit Contract negotiation Reset Initiator Reset Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 512 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.52, "Steps for a Soft Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.25, "Soft Reset" above. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder 1 The Policy Engine directs the Protocol Layer to generate a Soft_Reset Message to request a Soft Reset. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Soft_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Soft_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Soft_Reset Message to the Protocol Layer. 5 Protocol Layer does not check the MessageID in the incoming Message and resets MessageIDCounter, stored MessageID and RetryCounter. The Protocol Layer forwards the received Soft_Reset Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Soft_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 513 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The reset is complete and protocol communication can restart. Port Partners perform an Explicit Contract Negotiation to re- synchronize their state machines. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder Page 514 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5 Data Reset 8.3.2.5.1 DFP Initiated Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP is also the VCONN Source and initiates a Data Reset. Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.26 DFP Initiated Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Tell DPM to perform Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete Start CRCReceiveTimer 23: Data_Reset_Complete received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 515 Table 8.53, "Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" above. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to perform a Data Reset. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 516 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The Data Reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 517 8.3.2.5.2 DFP Receives Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and is the VCONN Source. Figure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.27 DFP Receives Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Tell DPM to perform a Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete 23: Data_Reset_Complete received Inform DPM Data Reset is complete 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Page 518 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.54, "Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource" below provides a detailed explanation of what happens at each labeled step in FFigure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" above. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 519 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the DPM to perform a Data Reset. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Page 520 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.3 DFP Initiated Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP initiates a Data Reset and the UFP is the VCONN Source. Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.28 DFP Initiated Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Start VCONNDischargeTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset Request DPM to turn off VCONN DPM indicates VCONN is off 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete Start CRCReceiveTimer 32: Data_Reset_Complete received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 521 Table 8.55, "Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" above. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and starts the VCONNDischargeTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 522 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests the DPM to turn off VCONN. 19 When the DPM indicates VCONN has been turned off the Policy Engine tells the Protocol Layer to form an PS_RDY Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 22 Protocol Layer stores the MessageID of the incoming Message. 23 The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and tells the DPM to perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 523 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Page 524 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.4 DFP Receives Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and the UFP is the VCONN Source. Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.29 DFP Receives a Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer Tell DPM to turn off VCONN. 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Start VCONNDischargeTimer DPM indicates that VCONN has been turned off. 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete 32: Data_Reset_Complete received Inform DPM Data Reset is complete 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 525 Table 8.56, "Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" above. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to turn off VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 526 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNDischargeTimer. 19 When the DPM indicates that VCONN has been turned off the Policy Engine directs the Protocol Layer to generate a PS_RDY Message to request a Soft Reset. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and requests the DPM perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 527 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Page 528 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6 Hard Reset The following sections describe the steps required for a USB Power Delivery Hard Reset. The Hard Reset returns the operation of the USB Power Delivery to default Power Role/Data Role and operating voltage/current. During the Hard Reset USB Power Delivery PHY Layer communications Shall be disabled preventing communication between the Port Partner. Note: Hard Reset, in this case, is applied to the USB Power Delivery capability of an individual Port on which the Hard Reset is requested. A side effect of the Hard Reset is that it might reset other functions on the Port such as USB. 8.3.2.6.1 Source Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Source. Figure 8.30, "Source initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.30 Source initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink Hard Reset Complete Reset MessageIDCounter and RetryCounter Reset MessageIDCounter and RetryCounter 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN 9: Hard Reset Complete Channel enabled Channel enabled 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN Channel disabled Channel disabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 529 Table 8.57, "Steps for Source initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.30, "Source initiated Hard Reset" above. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter and RetryCounter. 5 The Protocol Layer informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation. and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Page 530 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 531 8.3.2.6.2 Sink Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Sink. Figure 8.31, "Sink Initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.31 Sink Initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 9: Hard Reset Complete Channel enabled 2: Send Hard Reset 5: Hard Reset received Channel enabled Page 532 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.58, "Steps for Sink initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.31, "Sink Initiated Hard Reset" above. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 533 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink Page 534 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6.3 Source Initiated Hard Reset - Sink Long Reset This is an example of a Hard Reset operation when initiated by a Source. In this example the Sink is slow responding to the reset causing the Source to send multiple Source_Capabilities Messages before it receives a GoodCRC Message response. Figure 8.32, "Source initiated reset - Sink long reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.32 Source initiated reset - Sink long reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 6: Power Supply Reset 11: Power Sink Reset 13: Send Capabilities 14: Capabilities 15: Capabilities + CRC 16: Capabilities Start CRCReceiveTimer Store copy of MessageID 17: Capabilities received 18: GoodCRC 19: GoodCRC + CRC 20: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 21: Capabilities sent Stop SourceCapabilitiesTimer Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 8: Send Capabilities 9: Capabilities 10: Capabilities + CRC Run SourceCapabilityTimer Send Capabilities messages until GoodCRC response is received. 12: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 7: Hard Reset Complete Channel enabled Channel enabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 535 Table 8.59, "Steps for Source initiated Hard Reset - Sink long reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.32, "Source initiated reset - Sink long reset" above. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 8 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Policy Engine starts the SourceCapabilityTimer. The SourceCapabilityTimer times out one or more times until a GoodCRC Message response is received. 9 Protocol Layer creates the Message and passes to PHY Layer. 10 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. Note: Source_Capabilities Message not received since channel is disabled. 11 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. Page 536 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 12 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 13 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Starts the SourceCapabilityTimer. 14 Protocol Layer creates the Message and passes to PHY Layer. 15 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 16 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 17 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 18 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 19 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 20 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 21 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the SourceCapabilityTimer, stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 537 8.3.2.7 Power Role Swap 8.3.2.7.1 Source Initiated Power Role Swap 8.3.2.7.1.1 Source Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap sequence. Page 538 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.33 Successful Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply stops sourcing power CC -> Rd 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Tell Power Supply to stop sourcing power Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Sink to start sinking power Reset Protocol Layer New Power Roles Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 539 Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" above. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine requests its power supply to stop supplying power and stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 540 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the PSSourceOffTimer and tells the power supply to stop sinking current. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Message to Sink, creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 541 30 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Page 542 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.1.2 Source Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  An Reject Message in response to the PR_Swap Message. Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.34 Rejected Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 543 Table 8.61, "Steps for a Rejected Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" above. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 544 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 545 8.3.2.7.1.3 Source Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, with a wait response, initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.35 Power Role Swap Sequence with wait Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 546 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.62, "Steps for a Source Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" above. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 547 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port Page 548 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2 Sink Initiated Power Role Swap 8.3.2.7.2.1 Sink Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 549 Figure 8.36 Successful Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Supply to start sinking power Reset Protocol Layer Tell Power Supply to stop sourcing power Power Supply stops sourcing power CC -> Rd Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 550 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" above. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer and tells the power supply to stop sinking current. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 551 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the power supply to stop supplying power. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 552 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer, informs the power supply that it can start consuming power. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 553 8.3.2.7.2.2 Sink Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Reject Message in response to the PR_Swap Message. Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.37 Rejected Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 554 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.64, "Steps for a Rejected Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" above. Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 555 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 556 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2.3 Sink Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, responded to with wait, initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.38 Power Role Swap Sequence with wait Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 557 Table 8.65, "Steps for a Sink Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" above. Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 558 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Wait Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 559 8.3.2.8 Fast Role Swap This is an example of a successful Fast Role Swap operation initiated by a Port that is initially a Source and therefore has Rp pulled up on its CC wire and which has lost power and needs to get vSafe5V quickly. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are several distinct phases to the Fast Role Swap Negotiation:  The Initial Source stops driving its power output which starts transitioning to vSafe0V and send the Fast Role Swap Request on the CC wire; these could occur in either order or simultaneously.  The Initial Sink stops sinking power. At this point the New Source still has Rd asserted and the New Sink still has Rp asserted.  An FR_Swap Message is sent by the New Source within tFRSwapInit of detecting the Fast Swap signal.  An Accept Message is sent by the New Sink in response to the FR_Swap Message.  The New Sink asserts Rd and sends a PS_RDY Message indicating that the voltage on VBUS is at or below vSafe5V.  The New Source asserts Rp and sends a PS_RDY Message indicating that it is acting as a Source and is sup- plying vSafe5V. Note: The New Source can start applying VBUS when VBUS is at or below vSafe5V (max) but will start driving VBUS to vSafe5V no later than tSrcFRSwap after detecting both the Fast Role Swap Request and that VBUS has dropped below vSafe5V (min). Figure 8.39, "Successful Fast Role Swap Sequence" shows the Messages as they flow across the bus and within the devices to accomplish the Fast Role Swap. Page 560 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.39 Successful Fast Role Swap Sequence : Protocol 1: Send FR_Swap : PHY : PHY : Protocol 2:FR_Swap 3: FR_Swap + CRC 4: FR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: FR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:FR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate FR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Stop PSSourceOnTimer Reset Protocol Layer Power Supply acting as a Sink and VBUS at or below vSafe5V CC -> Rd vSafe5V is being sourced by the new Source Stop PSSourceOffTimer CC -> Rp New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Tell Power Supply to Stop sourcing power and switch to Sink operation Signal Fast Swap on the CC Wire Fast Role Swap signal detected on CC Wire Tell Power Supply to stop sinking current. Fast Swap signal (CC driven to Gnd through rFRSwapTx or rFRSwapCableTx) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 561 Table 8.66, "Steps for a Successful Fast Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.39, "Successful Fast Role Swap Sequence" above. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. The DPM detects Fast Swap on the CC wire and tells the power supply to stop sinking current. The Policy Engine directs the Protocol Layer to send an FR_Swap Message within tFRSwapInit of detecting the Fast Swap signal. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. The DPM tells the Power Supply to stop sourcing power and switch to Sink operation. The DPM signals Fast Swap on the CC wire by driving CC to ground with a resistance of less than rFRSwapTx for at least tFRSwapTx. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the FR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the FR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received FR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the FR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer. Page 562 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The Policy Engine determines its power supply is no longer supplying VBUS and is acting as a Sink. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 563 28 The Policy Engine directs the DPM to apply the Rp pull up. Note: At some point (either before or after receiving the PS_RDY Message) the New Source has ap- plied vSafe5V no later than tSrcFRSwap after detecting the Fast Role Swap Request and that VBUS has dropped below vSafe5V. Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Fast Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Page 564 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9 Data Role Swap 8.3.2.9.1 Data Role Swap, Initiated by UFP Operating as Sink 8.3.2.9.1.1 Data Role Swap, Initiated by UFP Operating as Sink (Accept) Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.40 Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 565 Table 8.67, "Steps for Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" above. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 566 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 567 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.41 Rejected Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Page 568 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.68, "Steps for Rejected Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" above. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 569 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Page 570 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Sink (Wait) Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.42 Data Role Swap with Wait, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 571 Table 8.69, "Steps for Data Role Swap with Wait, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" above. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 572 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 573 8.3.2.9.2 Data Role Swap, Initiated by UFP Operating as Source 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Accept) Figure 8.43, "Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.43 Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 574 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.70, "Steps for Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.43, "Data Role Swap, UFP operating as Source initiates" above. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 575 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), and Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and still operating as a Sink (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 576 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Reject) Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.44 Rejected Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 577 Table 8.71, "Steps for Rejected Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" above. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 578 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 579 8.3.2.9.2.3 Data Role Swap, Initiated by UFP Operating as Source (Wait) Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.45 Data Role Swap with Wait, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Page 580 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.72, "Steps for Data Role Swap with Wait, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" above. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 581 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 582 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3 Data Role Swap, Initiated by DFP Operating as Source 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Accept) Figure 8.46, "Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.46 Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 583 Table 8.73, "Steps for Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.46, "Data Role Swap, DFP operating as Source initiates" above. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 584 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 585 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Reject) Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.47 Rejected Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 586 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.74, "Steps for Rejected Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" above. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 587 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Page 588 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Source (Wait) Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed by wait. Figure 8.48 Data Role Swap with Wait, DFP operating as Source initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 589 Table 8.75, "Steps for Data Role Swap with Wait, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" above. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 590 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 591 8.3.2.9.4 Data Role Swap, Initiated by DFP Operating as Sink 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Accept) Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.49 Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) Page 592 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.76, "Steps for Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" above. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 593 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP, still operating as a Sink (Rd asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 594 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Reject) Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.50 Rejected Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 595 Table 8.77, "Steps for Rejected Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" above. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 596 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 597 8.3.2.9.4.3 Data Role Swap, Initiated by DFP Operating as Sink (Wait) Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.51 Data Role Swap with Wait, DFP operating as Sink initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Page 598 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.78, "Steps for Data Role Swap with Wait, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" above. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 599 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 600 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10 VCONN Swap 8.3.2.10.1 VCONN Source Swap, initiated by VCONN Source 8.3.2.10.1.1 VCONN Source Swap, initiated by VCONN Source (Accept) Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source role. Figure 8.52 Successful VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Vconn is on 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Stop SenderResponseTimer Start VCONNOnTimer Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN has been swapped VCONN off VCONN Source Tell power supply to start supplying VCONN VCONN is off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 601 Table 8.79, "Steps for Source to Sink VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" above. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 602 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine asks the DPM to turn on VCONN. 19 The DPM informs the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Source it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 VCONN is off. Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Port Partners have swapped VCONN Source role. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 603 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Reject) Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.53 Rejected VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Page 604 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.80, "Steps for Rejected VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" above. Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 605 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off Page 606 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.1.3 VCONN Source Swap, initiated by VCONN Source (Wait) Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is told to wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.54 VCONN Source Swap with Wait, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 607 Table 8.81, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" above. Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 608 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 609 8.3.2.10.2 VCONN Source Swap, initiated by non-VCONN Source 8.3.2.10.2.1 VCONN Source Swap, initiated by non-VCONN Source (Accept) Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source. Figure 8.55 VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port Vconn is on Start VCONNOnTimer VCONN Source VCONN Off Stop SenderResponseTimer Tell power supply to start supplying VCONN 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Source is supplying VCONN Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN is off Page 610 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.82, "Steps for VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" above. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 611 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNOnTimer. 19 The DPM tells the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Sink it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. VCONN is off. The Port Partners have swapped VCONN Source role. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Page 612 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.2.2 VCONN Source Swap, initiated by non-VCONN Source (Reject) Figure 8.56, "Rejected VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap which is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.56 Rejected VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 613 Table 8.83, "Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.56, "Rejected VCONN Source Swap, initiated by non- VCONN Source" above. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 614 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 615 8.3.2.10.2.3 VCONN Source Swap (Wait) Figure 8.57, "VCONN Source Swap with Wait" shows an example where the Port requests a VCONN Swap which is delayed with a wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.57 VCONN Source Swap with Wait : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Page 616 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.84, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.57, "VCONN Source Swap with Wait" above. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 617 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source Page 618 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11 Additional Capabilities, Status and Information 8.3.2.11.1 Alert 8.3.2.11.1.1 Source sends Alert to a Sink Figure 8.58, "Source Alert to Sink" shows an example sequence between a Source and a Sink where the Source alerts the Sink that there has been a status change. This AMS will be followed by getting the Source status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.58 Source Alert to Sink : Sink Policy Engine : Protocol : PHY : PHY : Protocol : Source Policy Engine Sink Port Source Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 619 Table 8.85, "Steps for Source Alert to Sink" below provides a detailed explanation of what happens at each labeled step in Figure 8.58, "Source Alert to Sink" above. Table 8.85 Steps for Source Alert to Sink Step Sink Source 1 The DPM indicates a Source alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 620 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.1.2 Sink sends Alert to a Source Figure 8.59, "Sink Alert to Source" shows an example sequence between a Source and a Sink where the Sink alerts the Source that there has been a status change. This AMS will be followed by getting the Sink status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.59 Sink Alert to Source : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine Source Port Sink Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 621 Table 8.86, "Steps for Sink Alert to Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.59, "Sink Alert to Source" above. Table 8.86 Steps for Sink Alert to Source Step Source Sink 1 The DPM indicates a Sink alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 622 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2 Status 8.3.2.11.2.1 Sink Gets Source Status Figure 8.60, "Sink Gets Source Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Sink gets more details on the change. Figure 8.60 Sink Gets Source Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 623 Table 8.87, "Steps for a Sink getting Source Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.60, "Sink Gets Source Status" above. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 624 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Source has informed the Sink of its present status. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 625 8.3.2.11.2.2 Source Gets Sink Status Figure 8.61, "Source Gets Sink Status" shows an example sequence between a Source and a Sink where, after the Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Source gets more details on the change. Figure 8.61 Source Gets Sink Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink Status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Page 626 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.88, "Steps for a Source getting Sink Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.61, "Source Gets Sink Status" above. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 627 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Sink has informed the Source of its present status. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port Page 628 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2.3 VCONN Source Gets Cable Plug Status Figure 8.62, "VCONN Source Gets Cable Plug Status" shows an example sequence between a VCONN Source and a Cable Plug where, after the VCONN Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the VCONN Source gets more details on the change. Figure 8.62 VCONN Source Gets Cable Plug Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Status Information from DPM : Policy Engine : Policy Engine VCONN Source Port Cable Plug Stop SenderResponseTimer 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 629 Table 8.89, "Steps for a VCONN Source getting Cable Plug Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.62, "VCONN Source Gets Cable Plug Status" above. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug 1 Policy Engine directs the Protocol Layer to send a Get_Status Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 630 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Cable Plug has informed the VCONN Source of its present status. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 631 8.3.2.11.2.4 Sink Gets Source PPS Status Figure 8.63, "Sink Gets Source PPS Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a PPS status change, the Sink gets more details on the change. Figure 8.63 Sink Gets Source PPS Status : Protocol 1: Send Get_PPS_Status : PHY : PHY : Protocol 2:Get_PPS_Status 3: Get_PPS_Status + CRC 4: Get_PPS_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_PPS_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_PPS_Status sent Start SenderResponseTimer 10: Send PPS_Status 11: PPS_Status 12: PPS_Status + CRC 13: PPS_Status Check MessageID against local copy Store copy of MessageID 14: PPS_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source PPS Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: PPS_Status sent Page 632 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.90, "Steps for a Sink getting Source PPS status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.63, "Sink Gets Source PPS Status" above. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_PPS_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_PPS_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_PPS_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_PPS_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_PPS_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a PPS_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the PPS_Status Message. PHY Layer appends a CRC and sends the PPS_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PPS_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 633 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PPS_Status Message was successfully sent. The Source has informed the Sink of its present PPS status. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port Page 634 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3 Source/Sink Capabilities 8.3.2.11.3.1 SPR 8.3.2.11.3.1.1 Sink Gets Source Capabilities Figure 8.64, "Sink Gets Source's Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source Capabilities. Figure 8.64 Sink Gets Source's Capabilities : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Source_Capabilities sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 635 Table 8.91, "Steps for a Sink getting Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.64, "Sink Gets Source's Capabilities" above. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 636 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its capabilities. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 637 8.3.2.11.3.1.2 Dual-Role Source Gets Source Capabilities from a Dual-Role Sink Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as a Source. Figure 8.65 Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 638 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.92, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" above. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 639 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its capabilities. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 640 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.1.3 Source Gets Sink Capabilities Figure 8.66, "Source Gets Sink's Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink Capabilities. Figure 8.66 Source Gets Sink's Capabilities : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 641 Table 8.93, "Steps for a Source getting Sink Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.66, "Source Gets Sink's Capabilities" above. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 642 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its capabilities. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 643 8.3.2.11.3.1.4 Dual-Role Sink Get Sink Capabilities from a Dual-Role Source Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.67 Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 644 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.94, "Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" above. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 645 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as a Sink. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 646 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2 EPR 8.3.2.11.3.2.1 Sink Gets EPR Source Capabilities Figure 8.68, "Sink Gets Source's EPR Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's EPR Capabilities. Figure 8.68 Sink Gets Source's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 647 Table 8.95, "Steps for a Sink getting EPR Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.68, "Sink Gets Source's EPR Capabilities" above. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present EPR Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 648 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its EPR Capabilities. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 649 8.3.2.11.3.2.2 Dual-Role Source Gets Source Capabilities from a Dual-Role EPR Sink Figure 8.69, "Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as an EPR Source. Figure 8.69 Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 650 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.96, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.69, "Dual-Role Source Gets Dual- Role Sink's Capabilities as an EPR Source" above. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 651 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its EPR Capabilities. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 652 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2.3 Source Gets Sink EPR Capabilities Figure 8.70, "Source Gets Sink's EPR Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's EPR Capabilities. Figure 8.70 Source Gets Sink's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 653 Table 8.97, "Steps for a Source getting Sink EPR Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.70, "Source Gets Sink's EPR Capabilities" above. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 654 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its EPR Capabilities. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 655 8.3.2.11.3.2.4 Dual-Role Sink Get Sink EPR Capabilities from a Dual-Role Source Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.71 Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 656 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.98, "Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" above. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 657 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as an EPR Sink. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 658 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4 Extended Capabilities 8.3.2.11.4.1 Sink Gets Source Extended Capabilities Figure 8.72, "Sink Gets Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Extended Capabilities. Figure 8.72 Sink Gets Source's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 659 Table 8.99, "Steps for a Sink getting Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.72, "Sink Gets Source's Extended Capabilities" above. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 660 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Source has informed the Sink of its Extended Capabilities. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 661 8.3.2.11.4.2 Dual-Role Source Gets Source Capabilities Extended from a Dual- Role Sink Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Source gets the Dual-Role Power Sink's Extended Capabilities as a Source. Figure 8.73 Dual-Role Source Gets Dual-Role Sink's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 662 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.100, "Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" above. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Source which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 663 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its Extended Capabilities as a Source. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 664 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4.3 Source Gets Sink Extended Capabilities Figure 8.74, "Source Gets Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Extended Capabilities. Figure 8.74 Source Gets Sink's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 665 Table 8.101, "Steps for a Source getting Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.74, "Source Gets Sink's Extended Capabilities" above. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 666 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Sink has informed the Source of its Extended Capabilities. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 667 8.3.2.11.4.4 Dual-Role Sink Gets Sink Capabilities Extended from a Dual-Role Source Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Sink gets the Dual-Role Power Source's Extended Capabilities as a Sink. Figure 8.75 Dual-Role Sink Gets Dual-Role Source's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 668 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.102, "Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" above. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Sink which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 669 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Extended Capabilities as a Sink. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 670 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5 Battery Capabilities and Status 8.3.2.11.5.1 Sink Gets Battery Capabilities Figure 8.76, "Sink Gets Source's Battery Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery capabilities for a given Battery. Figure 8.76 Sink Gets Source's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 671 Table 8.103, "Steps for a Sink getting Source Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.76, "Sink Gets Source's Battery Capabilities" above. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 672 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Source has informed the Sink of the Battery capabilities for the requested Battery. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 673 8.3.2.11.5.2 Source Gets Battery Capabilities Figure 8.77, "Source Gets Sink's Battery Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery capabilities for a given Battery. Figure 8.77 Source Gets Sink's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 674 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.104, "Steps for a Source getting Sink Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.77, "Source Gets Sink's Battery Capabilities" above. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 675 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Sink has informed the Source of the Battery capabilities for the requested Battery. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port Page 676 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5.3 Sink Gets Battery Status Figure 8.78, "Sink Gets Source's Battery Status" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery status for a given Battery. Figure 8.78 Sink Gets Source's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 677 Table 8.105, "Steps for a Sink getting Source Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.78, "Sink Gets Source's Battery Status" above. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 678 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Source has informed the Sink of the Battery status for the requested Battery. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 679 8.3.2.11.5.4 Source Gets Battery Status Figure 8.79, "Source Gets Sink's Battery Status" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery status for a given Battery. Figure 8.79 Source Gets Sink's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 680 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.106, "Steps for a Source getting Sink Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.79, "Source Gets Sink's Battery Status" above. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 681 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Sink has informed the Source of the Battery status for the requested Battery. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port Page 682 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6 Manufacturer Information 8.3.2.11.6.1 Source Gets Port Manufacturer Information from a Sink Figure 8.80, "Source Gets Sink's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.80 Source Gets Sink's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 683 Table 8.107, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.80, "Source Gets Sink's Port Manufacturer Information" above. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 684 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 685 8.3.2.11.6.2 Sink Gets Port Manufacturer Information from a Source Figure 8.81, "Sink Gets Source's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.81 Sink Gets Source's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 686 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.108, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.81, "Sink Gets Source's Port Manufacturer Information" above. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 687 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port Page 688 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.3 Source Gets Battery Manufacturer Information from a Sink Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for one of its Batteries. Figure 8.82 Source Gets Sink's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 689 Table 8.109, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" above. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 690 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 691 8.3.2.11.6.4 Sink Gets Battery Manufacturer Information from a Source Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.83 Sink Gets Source's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 692 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.110, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" above. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 693 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port Page 694 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.5 VCONN Source Gets Manufacturer Information from a Cable Plug Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Manufacturer information. Figure 8.84 VCONN Source Gets Cable Plug's Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 695 Table 8.111, "Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" above. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 696 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Cable Plug has informed the Source of its manufacturer information. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 697 8.3.2.11.7 Country Codes 8.3.2.11.7.1 8.3.2.12.7.1Source Gets Country Codes from a Sink Figure 8.85, "Source Gets Sink's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's Country Codes. Figure 8.85 Source Gets Sink's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 698 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.112, "Steps for a Source getting Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.85, "Source Gets Sink's Country Codes" above. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 699 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port Page 700 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.7.2 Sink Gets Country Codes from a Source Figure 8.86, "Sink Gets Source's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.86 Sink Gets Source's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 701 Table 8.113, "Steps for a Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.86, "Sink Gets Source's Country Codes" above. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 702 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 703 8.3.2.11.7.3 VCONN Source Gets Country Codes from a Cable Plug Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Country Codes. Figure 8.87 VCONN Source Gets Cable Plug's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Codes sent Page 704 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.114, "Steps for a VCONN Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" above. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 705 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Cable Plug has informed the Source of its country codes. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug Page 706 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8 Country Information 8.3.2.11.8.1 Source Gets Country Information from a Sink Figure 8.88, "Source Gets Sink's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country information. Figure 8.88 Source Gets Sink's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 707 Table 8.115, "Steps for a Source getting Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.88, "Source Gets Sink's Country Information" above. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific Country Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 708 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 709 8.3.2.11.8.2 Sink Gets Country Information from a Source Figure 8.89, "Sink Gets Source's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.89 Sink Gets Source's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 710 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.116, "Steps for a Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.89, "Sink Gets Source's Country Information" above. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 711 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port Page 712 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8.3 VCONN Source Gets Country Information from a Cable Plug Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's country information. Figure 8.90 VCONN Source Gets Cable Plug's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 713 Table 8.117, "Steps for a VCONN Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" above. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 714 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Cable Plug has informed the Source of its country information. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 715 8.3.2.11.9 Revision Information 8.3.2.11.9.1 Source Gets Revision Information from a Sink Figure 8.91, "Source Gets Sink's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision information. Figure 8.91 Source Gets Sink's Revision Information : Protocol 1: Send Get_Revision : PHY : PHY : Protocol 2:Get_Revision 3: Get_Revision + CRC 4: Get_Revision Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Revision received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Revision sent Start SenderResponseTimer 10: Send Revision 11: Revision 12: Revision + CRC 13: Revision Check MessageID against local copy Store copy of MessageID 14: Revision received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Revision sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 716 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.118, "Steps for a Source getting Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.91, "Source Gets Sink's Revision Information" above. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 717 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port Page 718 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.9.2 Sink Gets Revision Information from a Source Figure 8.92, "Sink Gets Source's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision codes. Figure 8.92 Sink Gets Source's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 719 Table 8.119, "Steps for a Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.92, "Sink Gets Source's Revision Information" above. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 720 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 721 8.3.2.11.9.3 VCONN Source Gets Revision Information from a Cable Plug Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Revision information. Figure 8.93 VCONN Source Gets Cable Plug's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Page 722 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.120, "Steps for a VCONN Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" above. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 723 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Cable Plug has informed the Source of its Revision information. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug Page 724 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.10 Source Information 8.3.2.11.10.1 Sink Gets Source Information Figure 8.94, "Sink Gets Source's Information" shows an example sequence between a Source and a Sink when the Sink gets the Source's information. Figure 8.94 Sink Gets Source's Information : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 725 Table 8.121, "Steps for a Sink getting Source Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.94, "Sink Gets Source's Information" above. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 726 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Source has provided the Sink with its information. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 727 8.3.2.11.10.2 Dual-Role Source Gets Source Information from a Dual-Role Sink Figure 8.95, "Dual-Role Source Gets Dual-Role Sink's Information as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink's Information as a Source. Figure 8.95 Dual-Role Source Gets Dual-Role Sink's Information as a Source : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 728 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.122, "Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.95, "Dual-Role Source Gets Dual- Role Sink's Information as a Source" above. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 729 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Dual-Role Power Sink has provided the Dual-Role Power Source with its information. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 730 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12 Security 8.3.2.12.1 Source requests security exchange with Sink Figure 8.96, "Source requests security exchange with Sink" shows an example sequence for a security exchange between a Source and a Sink. Figure 8.96 Source requests security exchange with Sink : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 731 Table 8.123, "Steps for a Source requesting a security exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.96, "Source requests security exchange with Sink" above. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 732 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 733 8.3.2.12.2 Sink requests security exchange with Source Figure 8.97, "Sink requests security exchange with Source" shows an example sequence for a security exchange between a Sink and a Source. Figure 8.97 Sink requests security exchange with Source : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 734 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.124, "Steps for a Sink requesting a security exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.97, "Sink requests security exchange with Source" above. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 735 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port Page 736 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12.3 VCONN Source requests security exchange with Cable Plug Figure 8.98, "VCONN Source requests security exchange with Cable Plug" shows an example sequence for a security exchange between a VCONN Source and a Cable Plug. Figure 8.98 VCONN Source requests security exchange with Cable Plug : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Vconn Source Cable Plug 18: Security_Response sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 737 Table 8.125, "Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.98, "VCONN Source requests security exchange with Cable Plug" above. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 738 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 739 8.3.2.13 Firmware Update 8.3.2.13.1 Source requests firmware update exchange with Sink Figure 8.99, "Source requests firmware update exchange with Sink" shows an example sequence for a firmware update exchange between a Source and a Sink. Figure 8.99 Source requests firmware update exchange with Sink : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 740 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.126, "Steps for a Source requesting a firmware update exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.99, "Source requests firmware update exchange with Sink" above. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 741 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port Page 742 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.13.2 Sink requests firmware update exchange with Source Figure 8.100, "Sink requests firmware update exchange with Source" shows an example sequence for a firmware update exchange between a Sink and a Source. Figure 8.100 Sink requests firmware update exchange with Source : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 743 Table 8.127, "Steps for a Sink requesting a firmware update exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.100, "Sink requests firmware update exchange with Source" above. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Page 744 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 745 8.3.2.13.3 VCONN Source requests firmware update exchange with Cable Plug Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" shows an example sequence for a firmware update exchange between a VCONN Source and a Cable Plug. Figure 8.101 VCONN Source requests firmware update exchange with Cable Plug : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine VCONN Source Cable Plug 18: Firmware_Update_Response sent Page 746 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.128, "Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" above. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 747 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Page 748 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14 Structured VDM 8.3.2.14.1 Discover Identity 8.3.2.14.1.1 Initiator to Responder Discover Identity (ACK) Figure 8.102, "Initiator to Responder Discover Identity (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers identity information from the Responder. Figure 8.102 Initiator to Responder Discover Identity (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity ACK 11: Discover Identity ACK 12: Discover Identity ACK + CRC 13: Discover Identity ACK Check MessageID against local copy Store copy of MessageID 14: Discover Identity ACK received Stop VDMResponseTimer DPM evaluates Identity information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 749 Table 8.129, "Steps for Initiator to UFP Discover Identity (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.102, "Initiator to Responder Discover Identity (ACK)" above. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command ACK response. 11 Protocol Layer creates the Discover Identity Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 750 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command ACK response was successfully sent. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 751 8.3.2.14.1.2 Initiator to Responder Discover Identity (NAK) Figure 8.103, "Initiator to Responder Discover Identity (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a NAK. Figure 8.103 Initiator to Responder Discover Identity (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity NAK 11: Discover Identity NAK 12: Discover Identity NAK + CRC 13: Discover Identity NAK Check MessageID against local copy Store copy of MessageID 14: Discover Identity NAK received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Page 752 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.130, "Steps for Initiator to UFP Discover Identity (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.103, "Initiator to Responder Discover Identity (NAK)" above. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command NAK response. 11 Protocol Layer creates the Discover Identity Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 753 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder Page 754 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.1.3 Initiator to Responder Discover Identity (BUSY) Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a BUSY. Figure 8.104 Initiator to Responder Discover Identity (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity BUSY 11: Discover Identity BUSY 12: Discover Identity BUSY + CRC 13: Discover Identity BUSY Check MessageID against local copy Store copy of MessageID 14: Discover Identity BUSY received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 755 Table 8.131, "Steps for Initiator to UFP Discover Identity (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" above. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command BUSY response. 11 Protocol Layer creates the Discover Identity Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 756 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 757 8.3.2.14.2 Discover SVIDs 8.3.2.14.2.1 Initiator to Responder Discover SVIDs (ACK) Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers SVID information from the Responder. Figure 8.105 Initiator to Responder Discover SVIDs (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs ACK 11: Discover_SVIDs ACK 12: Discover_SVIDs ACK + CRC 13: Discover_SVIDs ACK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs ACK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 758 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.132, "Steps for DFP to UFP Discover SVIDs (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" above. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command ACK response. 11 Protocol Layer creates the Discover SVIDs Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 759 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command ACK response was successfully sent. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder Page 760 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (NAK) Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a NAK. Figure 8.106 Initiator to Responder Discover SVIDs (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs NAK 11: Discover_SVIDs NAK 12: Discover_SVIDs NAK + CRC 13: Discover_SVIDs NAK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs NAK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 761 Table 8.133, "Steps for DFP to UFP Discover SVIDs (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" above. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command NAK response. 11 Protocol Layer creates the Discover SVIDs Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 762 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command NAK response was successfully sent. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 763 8.3.2.14.2.3 Initiator to Responder Discover SVIDs (BUSY) Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a BUSY. Figure 8.107 Initiator to Responder Discover SVIDs (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs BUSY 11: Discover_SVIDs BUSY 12: Discover_SVIDs BUSY + CRC 13: Discover_SVIDs BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs BUSY received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 764 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.134, "Steps for DFP to UFP Discover SVIDs (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" above. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command BUSY response. 11 Protocol Layer creates the Discover SVIDs Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 765 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command BUSY response was successfully sent. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder Page 766 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3 Discover Modes 8.3.2.14.3.1 Initiator to Responder Discover Modes (ACK) Figure 8.108, "Initiator to Responder Discover Modes (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers Mode information from the Responder. Figure 8.108 Initiator to Responder Discover Modes (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes ACK 11: Discover_Modes ACK 12: Discover_Modes ACK + CRC 13: Discover_Modes ACK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes ACK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 767 Table 8.135, "Steps for DFP to UFP Discover Modes (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.108, "Initiator to Responder Discover Modes (ACK)". Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command ACK response. 11 Protocol Layer creates the Discover Modes Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 768 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command ACK response was successfully sent. Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 769 8.3.2.14.3.2 Initiator to Responder Discover Modes (NAK) Figure 8.109, "Initiator to Responder Discover Modes (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a NAK. Figure 8.109 Initiator to Responder Discover Modes (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes NAK 11: Discover_Modes NAK 12: Discover_Modes NAK + CRC 13: Discover_Modes NAK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes NAK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Page 770 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.136, "Steps for DFP to UFP Discover Modes (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.109, "Initiator to Responder Discover Modes (NAK)". Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 771 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP Page 772 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3.3 Initiator to Responder Discover Modes (BUSY) Figure 8.110, "Initiator to Responder Discover Modes (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a BUSY. Figure 8.110 Initiator to Responder Discover Modes (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes BUSY 11: Discover_Modes BUSY 12: Discover_Modes BUSY + CRC 13: Discover_Modes BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_Modes BUSY received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 773 Table 8.137, "Steps for DFP to UFP Discover Modes (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.110, "Initiator to Responder Discover Modes (BUSY)". Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 774 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 775 8.3.2.14.4 Enter/Exit Mode 8.3.2.14.4.1 DFP to UFP Enter Mode Figure 8.111, "DFP to UFP Enter Mode" shows an example sequence between a DFP and a UFP that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.111 DFP to UFP Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP Supported SVIDS/Modes discovered Enter USB Safe State 37: Send Enter Mode 38: Enter Mode 39: Enter Mode + CRC 40: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 41: Enter Mode received 42: GoodCRC 43: GoodCRC + CRC 44: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 45: Enter Mode sent Start VDMModeEntryTimer 46: Send Enter Mode ACK 47: Enter Mode ACK 48: Enter Mode ACK + CRC 49: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 50: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 51: GoodCRC 52: GoodCRC + CRC 53: GoodCRC 54: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Operation USB Operation Evaluate Enter Mode request Enter New Mode New Mode Entered Page 776 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.138, "Steps for DFP to UFP Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.111, "DFP to UFP Enter Mode" above. Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. The Policy Engine directs the Protocol Layer to send an Enter Mode Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. The Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 777 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and UFP are operating in the new Mode Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP Page 778 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.2 DFP to UFP Exit Mode Figure 8.112, "DFP to UFP Exit Mode" shows an example sequence between a DFP and a UFP, where the DFP commands the UFP to exit the only Active Mode. Figure 8.112 DFP to UFP Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 779 Table 8.139, "Steps for DFP to UFP Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.112, "DFP to UFP Exit Mode" above. Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The UFP is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. The Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 780 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and UFP are in USB Operation Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 781 8.3.2.14.4.3 DFP to Cable Plug Enter Mode Figure 8.113, "DFP to Cable Plug Enter Mode" shows an example sequence between a DFP and a Cable Plug that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.113 DFP to Cable Plug Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug Supported SVIDs/Modes Discovered Enter USB Safe Mode Wait tCableMessage before transmission 19: Send Enter Mode 20: Enter Mode 21: Enter Mode + CRC 22: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Enter Mode received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Enter Mode sent Start VDMModeEntryTimer 10: Send Enter Mode ACK 11: Enter Mode ACK 12: Enter Mode ACK + CRC 13: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 14: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Mode USB Mode Evaluate Enter Mode request Enter New Mode Wait tCableMessage before transmission New Mode Entered Page 782 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.140, "Steps for DFP to Cable Plug Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.113, "DFP to Cable Plug Enter Mode" above. Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. tCableMessage after the last GoodCRC Message was sent the Policy Engine directs the Protocol Layer to send an Enter Mode Command request. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 783 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and Cable Plug are operating in the new Mode Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug Page 784 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.4 DFP to Cable Plug Exit Mode Figure 8.114, "DFP to Cable Plug Exit Mode" shows an example sequence between a USB Type-C® DFP and a Cable Plug, where the DFP commands the Cable Plug to exit an Active Mode. Figure 8.114 DFP to Cable Plug Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation Wait tCableMessage before transmission USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 785 Table 8.141, "Steps for DFP to Cable Plug Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.114, "DFP to Cable Plug Exit Mode" above. Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The Cable Plug is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 786 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and Cable Plug are in USB Operation Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 787 8.3.2.14.4.5 Initiator to Responder Attention Figure 8.115, "Initiator to Responder Attention" shows an example sequence between an Initiator and a Responder, where the Initiator requests attention from the Responder. Figure 8.115 Initiator to Responder Attention : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Responder Initiator 1: Send Attention 2: Attention 3: Attention + CRC 4: Attention Check MessageID against local copy Store copy of MessageID 5: Attention received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Attention sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Page 788 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.142, "Steps for Initiator to Responder Attention" below provides a detailed explanation of what happens at each labeled step in Figure 8.115, "Initiator to Responder Attention" above. Table 8.142 Steps for Initiator to Responder Attention Step Responder Initiator 1 The DPM requests attention. The Policy Engine tells the Protocol Layer to form an Attention Command request. 2 Protocol Layer creates the Attention Command request and passes to PHY Layer. 3 PHY Layer receives the Attention Command request and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Attention Command request. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Attention Command request information to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Attention Command request was successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 789 8.3.2.15 Built in Self-Test (BIST) 8.3.2.15.1 BIST Carrier Mode The following is an example of a BIST Carrier Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.116, "BIST Carrier Mode Test" shows the Messages as they flow across the bus and within the devices. This test enables the measurement of power supply noise and frequency drift. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Carrier Mode BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT starts sending the Test Pattern. 5) Operator does the measurements. 6) The test ends after tBISTContMode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.1, "BIST Carrier Mode". Figure 8.116 BIST Carrier Mode Test : Protocol 1: Send BIST(Carrier Mode) : PHY : PHY : Protocol 2: BIST(Carrier Mode) 3: BIST(Carrier Mode) + CRC 4: BIST(Carrier Mode) Start CRCReceiveTimer 5: BIST(Carrier Mode) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Carrier Mode) sent : Policy Engine : Policy Engine Go to BIST Carrier Mode Tester UUT 12: Send Test Pattern 13: Send Test Pattern 14: Test Pattern Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (after tBISTContMode) Enter BIST Carrier Mode mode 10: Go to BIST Carrier Mode 11: Go to BIST Carrier Mode Page 790 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.143, "Steps for BIST Carrier Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.116, "BIST Carrier Mode Test" above. Table 8.143 Steps for BIST Carrier Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Carrier Mode, to put the UUT into BIST Carrier Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Carrier Mode. The Policy Engine goes to BIST Carrier Mode. 11 Protocol Layer tells PHY Layer to go into BIST Carrier Mode. UUT enters BIST Carrier Mode. 12 The Policy Engine directs the Protocol Layer to start generation of the Test Pattern. 13 Protocol Layer directs the PHY Layer to generate the Test Pattern. 14 PHY Layer receives the Test Pattern stream. PHY Layer generates a continuous Test Pattern stream. The UUT exits BIST Carrier Mode after tBISTContMode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 791 8.3.2.15.2 BIST Test Data Mode The following is an example of a BIST Test Data Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.117, "BIST Test Data Test" shows the Messages as they flow across the bus and within the devices. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Test Data BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) Steps 2and 3 are repeated any number of times. 5) The test ends after Hard Reset Signaling is issued. See also Section 5.9.2, "BIST Test Data Mode" and Section 6.4.3.2, "BIST Test Data Mode". Page 792 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.117 BIST Test Data Test : Protocol 1: Send BIST(Test Data) : PHY : PHY : Protocol 2: BIST(Test Data) 3: BIST(Test Data) + CRC 4: BIST(Test Data) Start CRCReceiveTimer 5: BIST(Test Data) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Test Data) sent : Policy Engine : Policy Engine Go to BIST Test Data mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (Hard Reset) Enter BIST Test Data mode 10: Send BIST(Test Data) 11: BIST(Test Data) 12: BIST(Test Data) + CRC 13: BIST(Test Data) Start CRCReceiveTimer 14: BIST(Test Data) received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: BIST(Test Data) sent Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 793 Table 8.144, "Steps for BIST Test Data Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.117, "BIST Test Data Test" above. Table 8.144 Steps for BIST Test Data Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. UUT enters BIST Test Data Mode. 10 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 13 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. Page 794 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. Repeat steps 10-18 any number of times The UUT exits BIST Test Data Mode after a Hard Reset Table 8.144 Steps for BIST Test Data Test Step Tester UUT Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 795 8.3.2.15.3 BIST Shared Capacity Test Mode The following is an example of a BIST Shared Capacity Test Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.118, "BIST Share Capacity Mode Test" shows the Messages as they flow across the bus and within the devices. This test places the UUT in a compliance test mode where the maximum Source capability is always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Shared Test Mode Entry BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT enters BIST Shared Capacity Test Mode. 5) Operator does the measurements. 6) Tester sends a BIST Message with a BIST Shared Test Mode Exit BIST Data Object. 7) UUT answers with a GoodCRC Message. 8) UUT exits BIST Shared Capacity Test Mode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.3, "BIST Shared Capacity Test Mode". Figure 8.118 BIST Share Capacity Mode Test 12: Send BIST(Shared Capacity Test Mode Exit) 13: BIST(Shared Capacity Test Mode Exit) 14: BIST(Shared Capacity Test Mode Exit) + CRC 15: BIST(Shared Capacity Test Mode Exit) Start CRCReceiveTimer 16: BIST(Shared Capacity Test Mode Exit) received 17: GoodCRC 18: GoodCRC + CRC 19: GoodCRC 20: BIST(Shared Capacity Test Mode) sent Go to BIST Shared Capacity Test Mode Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID EXit BIST Shared Capacity Test Mode mode 21: Exit BIST Shared Capacity Test Mode 22: Exit BIST Shared Capacity Test Mode : Protocol 1: Send BIST(Shared Capacity Test Mode Entry) : PHY : PHY : Protocol 2: BIST(Shared Capacity Test Mode Entry) 3: BIST(Shared Capacity Test Mode Entry) + CRC 4: BIST(Shared Capacity Test Mode Entry) Start CRCReceiveTimer 5: BIST(Shared Capacity Test Mode Entry) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Shared Capacity Test Mode) sent : Policy Engine : Policy Engine Go to BIST Shared Capacity Test Mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Enter BIST Shared Capacity Test Mode mode 10: Go to BIST Shared Capacity Test Mode 11: Go to BIST Shared Capacity Test Mode Tester Performs Tests Page 796 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.145, "Steps for BIST Shared Capacity Test Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.118, "BIST Share Capacity Mode Test" above. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Entry, to put the UUT into BIST Shared Capacity Test Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY LayerPHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Shared Capacity Test Mode. The Policy Engine goes to BIST Shared Capacity Test Mode. 11 Protocol Layer tells PHY Layer to go into BIST Shared Capacity Test Mode. UUT enters BIST Shared Capacity Test Mode. Tester performs tests. 12 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Exit, to take the UUT out of BIST Shared Capacity Test Mode. 13 Protocol Layer creates the Message and passes to PHY Layer. 14 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 15 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 16 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 797 17 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 18 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 19 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 20 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 21 Policy Engine tells Protocol Layer to exit BIST Shared Capacity Test Mode. The Policy Engine exits to BIST Shared Capacity Test Mode. 22 Protocol Layer tells PHY Layer to exit BIST Shared Capacity Test Mode. UUT exits BIST Shared Capacity Test Mode. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT Page 798 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16 Enter USB 8.3.2.16.1 UFP Entering USB4 Mode 8.3.2.16.1.1 UFP Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the UFP. Figure 8.119, "UFP Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.119 UFP Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 799 Table 8.146, "Steps for UFP USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.119, "UFP Entering USB4 Mode (Accept)" above. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 800 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Both Port Partners enter [USB4] operation. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 801 8.3.2.16.1.2 UFP Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the UFP. Figure 8.120, "UFP Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.120 UFP Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 802 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.147, "Steps for UFP USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.120, "UFP Entering USB4 Mode (Reject)" above. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 803 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP Page 804 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.1.3 UFP Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the UFP at this time. Figure 8.121, "UFP Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.121 UFP Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait 14: Wait received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 805 Table 8.148, "Steps for UFP USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.121, "UFP Entering USB4 Mode (Wait)" above. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 806 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 807 8.3.2.16.2 Cable Plug Entering USB4 Mode 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the Cable Plug. Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.122 Cable Plug Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 808 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.149, "Steps for Cable Plug USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" above. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 809 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Cable Plug enters [USB4] operation. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug Page 810 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the Cable Plug. Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.123 Cable Plug Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 811 Table 8.150, "Steps for Cable Plug USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" above. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 812 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 813 8.3.2.16.2.3 Cable Plug Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the Cable Plug at this time. Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.124 Cable Plug Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 814 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.151, "Steps for Cable Plug USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" above. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 815 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug Page 816 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.17 Unstructured Vendor Defined Messages 8.3.2.17.1 Unstructured VDM Figure 8.125, "Unstructured VDM Message Sequence" shows an example sequence of an Unstructured VDM Transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.125 Unstructured VDM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send Unstructured VDM Start CRCReceive Timer 21 : Unstructured VDM 22 : Unstructured VDM + CRC 23 : Unstructured VDM Check MessageID against local copy Store Copy of MessageID 23 : Unstructured VDM Received Evaluate Unstructured VDM Reply with the application specific response which can be again a Unstructured VDM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send Unstructured VDM 11: Unstructured VDM 18: Unstructured VDM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : Unstructured VDM + CRC 16: GoodCRC + CRC 11: Unstructured VDM 15: GoodCRC 14: Unstructured VDM Received Process Unstructured VDM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : Unstructured VDM Sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 817 Table 8.152, "Steps for Unstructured VDM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.125, "Unstructured VDM Message Sequence" above. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send an Unstructured Vendor_Defined Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. PHY Layer receives the Unstructured Vendor_Defined Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Unstructured Vendor_Defined Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form an Unstructured Vendor_Defined Message. 11 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 12 PHY Layer receives the Unstructured Vendor_Defined Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 818 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 819 8.3.2.17.2 VDEM Figure 8.126, "VDEM Message Sequence" shows an example sequence of an VDEM transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.126 VDEM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send VDEM Start CRCReceive Timer 21 : VDEM 22 : VDEM + CRC 23 : VDEM Check MessageID against local copy Store Copy of MessageID 23 : VDEM Received Evaluate VDEM Reply with the application specific response which can be again a VDEM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send VDEM 11: VDEM 18: VDEM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : VDEM + CRC 16: GoodCRC + CRC 11: VDEM 15: GoodCRC 14: VDEM Received Process VDEM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : VDEM Sent Page 820 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.153, "Steps for VDEM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.126, "VDEM Message Sequence" above. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send a Vendor_Defined_Extended Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Vendor_Defined_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Vendor_Defined_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY LayerPHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form a Vendor_Defined_Extended Message. 11 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 12 PHY Layer receives the Vendor_Defined_Extended Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 821 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP Page 822 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3 State Diagrams 8.3.3.1 Introduction to state diagrams used in Chapter 8 The state diagrams defined in Section 8.3.3, "State Diagrams" are Normative and Shall define the operation of the Power Delivery Policy Engine. Note: These state diagrams are not intended to replace a well written and robust design. Figure 8.127 Outline of States Figure 8.127, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state. If there are also "Actions on exit" a list of actions carried out on exiting the state, then these are listed as well; otherwise, this box is omitted from the state. At the bottom the status of PD is listed:  “Power" which indicates the present output power for a Source Port or input power for a Sink Port.  “PD" which indicates the present Attachment status either "Attached", "Detached", or "unknown". Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&". In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams (e.g., Source Port or Sink Port state diagrams). Figure 8.128, "References to states" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the state and whether the state is a DFP or UFP. It has also been necessary to indicate conditional entry to either Source Port or Sink Port state diagrams. This is achieved by the use of a bulleted list indicating the preconditions (see example in Figure 8.129, "Example of state reference with conditions"). It is also possible that the entry and return states are the same. Figure 8.130, "Example of state reference with the same entry and exit" indicates a state reference where each referenced state corresponds to either the entry state or the exit state. <Name of State> Actions on entry: “List of actions to carry out on entering the state” Power (VI) = “Present power level” PD = “attachment status” Actions on exit: “List of actions to carry out on exiting the state” Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 823 Figure 8.128 References to states Figure 8.129 Example of state reference with conditions Figure 8.130 Example of state reference with the same entry and exit Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the particular state it is referenced. As soon as the state is exited then the timer is no longer active. Where the timers continue to run outside of the state (such as the NoResponseTimer), this is called out in the text. Timeouts of the timers are listed as conditions on state transitions. The SenderResponseTimer is a special case, as it May be stopped and started from outside the states in which it is used. To allow this to be done without over-complicating the state diagrams, the SenderResponseTimer is described with its own state diagram (Figure 8.131, "SenderResponseTimer Policy Engine State Diagram"). The control of this Timer is shared between the Policy Engine and the Chunking Layer. <Name of reference state> (<DFP | UFP>) Hard Reset: • Consumer or Consumer/Provider -> PE_SNK_.... • Provider/Consumer in Source role -> PE_SRC_... <Name of reference state 1> or <Name of reference state 2> (<DFP | UFP>) Page 824 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Conditions listed on state transitions will come from one of three sources and, when there is a conflict, Should be serviced in the following order: 1) Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.). 2) Events triggered within the Policy Engine e.g., timer timeouts. 3) Information and requests coming from the Device Policy Manager relating either to Local Policy, or to other modules which the Device Policy Manager controls such as power supply and USB-C® Port Control. Note: The following state diagrams are not intended to cover all possible corner cases that could be encountered. For example, where an outgoing Message is Discarded, due to an incoming Message by the Protocol Layer (see Section 6.12.2.3, "Protocol Layer Message Reception") it will be necessary for the higher layers of the system to handle a retry of the AMS that was being initiated, after first handling the incoming Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 825 8.3.3.1.1 SenderResponseTimer State Diagram Figure 8.131, "SenderResponseTimer Policy Engine State Diagram" below shows the state diagram for the Policy Engine in a Source Port or a Sink Port. The following sections describe operation in each of the states. Figure 8.131 SenderResponseTimer Policy Engine State Diagram 8.3.3.1.1.1 SRT_Stopped State The SRT_Stopped State Shall be the starting state for the SenderResponseTimer either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall stop incrementing the SR_Timer. The Policy Engine Shall transition to the SRT_Running State:  When the SenderResponseTimer is started from within a Policy Engine state, or  When a Start_SRT is requested from the Chunking Layer. 8.3.3.1.1.2 SRT_Running State On entry to the SRT_Running State the SenderResponseTimer state machine Shall:  Set the SR_Timer to zero  Start running SR_Timer. The SenderResponseTimer state machine Shall transition to the SRT_Expired State:  When the SR_Timer reaches its maximum count The SenderResponseTimer state machine Shall transition to the SRT_Stopped State:  When the SenderResponseTimer is stopped by exiting a Policy Engine state, or  When a Stop_SRT is requested from the Chunking Layer SRT_Stopped Actions on entry: Stop Incrementing SR_Timer1 Power-up | Hard Reset | SenderResponseTimer stopped on exit from Policy Engine State | Stop_SRT requested from Chunking Layer Actions on entry: Zero SR_Timer Start Incrementing SR_Timer1 SRT_Running SenderResponseTimer started from within Policy Engine State | Start_SRT requested from Chunking Layer Actions on entry: Inform Policy Engine of SenderResponseTimer timeout SRT_Expired SR_Timer1 reached maximum count Policy Engine informed 1) The SR_Timer is regarded as the mechanism within the SenderResponseTimer state diagram that implements the SenderResponseTimer. Page 826 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.1.1.3 SRT_Expired State On entry to the SRT_Running State the SenderResponseTimer state machine Shall Inform Policy Engine of SenderResponseTimer timeout The Policy Engine Shall then transition to the SRT_Stopped state:  When the Policy Engine has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 827 8.3.3.2 Policy Engine Source Port State Diagram Figure 8.132, "Source Port State Diagram" below shows the state diagram for the Policy Engine in a Source Port. The following sections describe operation in each of the states. Figure 8.132 Source Port State Diagram 1) Implementation of the CapsCounter is Optional. In the case where this is not implemented the Source Shall continue to send Source_Capabilities Messages each time the SourceCapabilityTimer times out. 2) Since the Sink is required to make a Valid request from the offered capabilities the expected transition is via "Request can be met" unless the Source Capabilities have changed since the last offer. 3) “Contract Invalid" means that the previously Negotiated voltage and Current values are no longer included in the Source's new Capabilities. If the Sink fails to make a Valid Request in this case, then Power Delivery operation is no lon- ger possible and Power Delivery mode is exited with a Hard Reset. Protocol LayerReset4 | SwapSourceStartTimer timeout PE_SRC_Discovery Actions on entry: Initialize and run SourceCapabilityTimer Power = Default (5V) or Implicit Contract PD = not Connected PE_SRC_Ready Actions on entry: Notify Protocol Layer of end of AMS8 Initialize and run DiscoverIdentityTimer7 Initialize and run SourcePPSCommTimer10 Initialize and run SourceEPRKeepAliveTimer11 Power = Explicit Contract PD = Connected PE_SRC_Transition_Supply Actions on entry: Send Accept message (within tReceiverResponse) Request Device Policy Manager to transition Power Supply Power = transition PD = Connected Actions on exit: Send PS_RDY message (In SPR Mode & Request Message) | (In EPR Mode & EPR_Request Message) PE_SRC_Negotiate_Capability Actions on entry: Get Device Policy Manager evaluation of sink request: • Can be met • Can’t be met • Could be met later from Power Reserve If the sink request for Operating Current or Operating Power can be met, but the sink still requires more power (“Capability Mismatch”) this information will be passed to Device Policy Manager4 Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SRC_Capability_Response Actions on entry: Send Reject message if request can’t be met Send Wait message if request could be met later from the Power Reserve and present Contract is still valid Power = DefauIt (5V) or Implicit/ Explicit Contract PD = Connected Start Explicit Contract (Reject message sent & Contract still valid) | Wait message sent PE_SRC_Send_Capabilities Actions on entry: Request present source capabilities from Device Policy Manager In SPR Mode Send Source_Capabilities Message In EPR Mode Send EPR_Source_Capabilities Message Increment CapsCounter (optional)1 If GoodCRC received: • stop NoResponseTimer • reset HardResetCounter and CapsCounter • initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SRC_Hard_Reset Actions on entry: Generate Hard Reset signalling Initialize and start NoResponseTimer Start PSHardResetTimer Increment HardResetCounter Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Request can’t be met | Request met later from Power Reserve Explicit Contract & Reject message sent & Contract Invalid4 PSHardResetTimer timeout Request can be met Power supply ready Power source at default (SourceCapabilityTimer timeout & CapsCounter ” nCapsCount1) Capabilities message sending failure (without GoodCRC) ¬ presently PD Connected6 In SPR Mode Request Message received | In EPR Mode EPR_Request Message received PE_SRC_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager12 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Hard reset signalling received SenderResponseTimer timeout not previously PD Connected6& NoResponseTimer timeout & HardResetCounter > nHardResetCount1 PSHardResetTimer timeout (SourceCapabilityTimer timeout & CapsCounter > nCapsCount1) | (not previously PD Connected6 & NoResponseTimer timeout & HardResetCounter > nHardResetCount1) PE_SRC_Startup Actions on entry: Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer (only after Swap) Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SRC_Transition_to_default Actions on entry: Request Device Policy Manager to request power supply Hard Resets to vSafe5V via vSafe0V Reset local HW Request Device Policy Manager to set Port Data Role to DFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected PE_SRC_Disabled Actions on entry: Disable Power Delivery Power = DefauIt (5V) PD =not Connected Actions on exit: Request Device Policy Manager to turn on VCONN Inform Protocol Layer Hard Reset complete ErrorRecovery previously PD Connected6 & NoResponseTimer timeout & HardResetCount > nHardResetCount PE_SRC_Wait_New_Capabilities Actions on entry: Wait for new Source Capabilities9 Power = DefauIt (5V) PD =Connected PE_SRC_Hard_Reset_Received Actions on entry: Start PSHardResetTimer Initialize and start NoResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Source capability change (from Device Policy Manager) no Explicit Contract & (Reject message sent | Wait message sent) Source capability change (from Device Policy Manager) | (In SPR Mode & Get_Source_Cap Message) | (In EPR Mode & EPR_Get_Source_Cap Message) Protocol Error Actions on exit: If the Source is initiating an AMS then notify the Protocol Layer than the first Message in an AMS will follow8 SourcePPSCommTimer timeout | SourceEPRKeepAliveTimer timeout PE_SRC_EPR_Keep_Alive Actions on entry: Send EPR_Keep_Alive_Ack Message Power = Explicit Contract PD = Connected EPR_Keep_Alive Message EPR_Keep_Alive_Ack Sent Hard Reset request from Device Policy Manager | EPR Mode & Request Message received | EPR Capable & SPR Mode & EPR_Request Message received (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities message sent PE_SRC_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Page 828 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) After a Power Swap the New Source is required to wait an additional tSwapSourceStart before sending a Source_Capabilities Message. This delay is not required when first starting up a system. 5) PD Connected is defined as a situation when the Port Partners are actively communicating. The Port Partners remain PD Connected after a Swap until there is a transition to Disabled or the connector is able to identify a Detach. 6) Port Partners are no longer PD Connected after a Hard Reset, but consideration needs to be given as to whether there has been a PD Connection while the Ports have been Attached to prevent unnecessary USB Type-C Error Recovery. 7) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 8) See Section 5.7, "Collision Avoidance", Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". 9) In the PE_SRC_Wait_New_Capabilities State the Device Policy Manager Should either decide to send no further Source Capabilities or Should send a different set of Source Capabilities. Continuing to send the same set of Source Capabilities could result in a live lock situation. 10) The SourcePPSCommTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sourc- es that do not support SPR PPS do not need to implement the SourcePPSCommTimer. 11) The SourceEPRKeepAliveTimer is only initialized and run when the Source is in EPR Mode; Sources that do not support EPR Mode do not need to implement the SourceEPRKeepAliveTimer. 12) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. 8.3.3.2.1 PE_SRC_Startup State PE_SRC_Startup Shall be the starting state for a Source Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the CapsCounter and reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state:  When the Protocol Layer reset has completed if the PE_SRC_Startup state was entered due to the system first starting up.  When the SwapSourceStartTimer times out if the PE_SRC_Startup state was entered as the result of a Power Role Swap. Note: Sources Shall remain in the PE_SRC_Startup state, without sending any Source_Capabilities Messages until a plug is Attached. 8.3.3.2.2 PE_SRC_Discovery State On entry to the PE_SRC_Discovery state the Policy Engine Shall initialize and run the SourceCapabilityTimer in order to trigger sending a Source_Capabilities Message. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The SourceCapabilityTimer times out and CapsCounter ≤ nCapsCount. The Policy Engine May Optionally go to the PE_SRC_Disabled state when:  The Port Partners are not presently PD Connected  And the SourceCapabilityTimer times out  And CapsCounter > nCapsCount. The Policy Engine Shall go to the PE_SRC_Disabled state when:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 829  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. Note: In the PE_SRC_Disabled state the Attached device is assumed to be unresponsive. The Policy Engine operates as if the device is Detached until such time as a Detach/Re-attach is detected. 8.3.3.2.3 PE_SRC_Send_Capabilities State Note: This state can be entered from the PE_SRC_Soft_Reset state. On entry to the PE_SRC_Send_Capabilities state the Policy Engine Shall request the present Port capabilities from the Device Policy Manager. The Policy Engine Shall then request the Protocol Layer to send a capabilities Message containing these capabilities. The Policy Engine Shall request:  A Source_Capabilities Message if the Source is in SPR Mode or  An EPR_Source_Capabilities Message if the Source is in EPR Mode. The Policy Engine Shall then increment the CapsCounter (if implemented). If a GoodCRC Message is received, then the Policy Engine Shall:  Stop the NoResponseTimer.  Reset the HardResetCounter and CapsCounter to zero. Note: The HardResetCounter Shall only be set to zero in this state and at power up; its value Shall be maintained during a Hard Reset.  Initialize and run the SenderResponseTimer. Once a Source_Capabilities Message has been received and acknowledged by a GoodCRC Message, the Sink is required to then send a Request Message within tSenderResponse. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received from the Sink and the Source is operating in SPR Mode or  An EPR_Request Message is received from the Sink and the Source is operating in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Discovery state when:  The Protocol Layer indicates that the Message has not been sent and we are presently not Connected. This is part of the Capabilities sending process whereby successful Message sending indicates connection to a PD Sink Port. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The SenderResponseTimer times out. In this case a transition back to USB Default Operation is required. When:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment)  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. The Policy Engine Shall do one of the following:  Transition to the PE_SRC_Discovery state.  Transition to the PE_SRC_Disabled state. Page 830 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: That in either case the Attached device is assumed to be unresponsive. The Policy Engine Should operate as if the device is Detached until such time as a Detach/Re-attach is detected. The Policy Engine Shall go to the ErrorRecovery state when:  The Port Partners have previously been PD Connected (the Source Port remains Attached to a Port it has had a PD Connection with during this Attachment)  And the NoResponseTimer times out.  And the HardResetCounter > nHardResetCount. 8.3.3.2.4 PE_SRC_Negotiate_Capability State On entry to the PE_SRC_Negotiate_Capability state the Policy Engine Shall ask the Device Policy Manager to evaluate the Request from the Attached Sink. The response from the Device Policy Manager Shall be one of the following:  The Request can be met.  The Request cannot be met  The Request could be met later from the Power Reserve. The Policy Engine Shall transition to the PE_SRC_Transition_Supply state when:  The Request can be met. The Policy Engine Shall transition to the PE_SRC_Capability_Response state when:  The Request cannot be met.  Or the Request can be met later from the Power Reserve. 8.3.3.2.5 PE_SRC_Transition_Supply State The Policy Engine Shall be in the PE_SRC_Transition_Supply state while the power supply is transitioning from one power to another. On entry to the PE_SRC_Transition_Supply state, the Policy Engine Shall request the Protocol Layer to send an Accept Message and inform the Device Policy Manager that it Shall transition the power supply to the Requested power level. Note: If the power supply is currently operating at the requested power no change will be necessary. On exit from the PE_SRC_Transition_Supply state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The Device Policy Manager informs the Policy Engine that the power supply is ready. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.2.6 PE_SRC_Ready State In the PE_SRC_Ready state the PD Source Shall be operating at a stable power with no ongoing Negotiation. It Shall respond to requests from the Sink, events from the Device Policy Manager. On entry to the PE_SRC_Ready state the Source Shall notify the Protocol Layer of the end of the Atomic Message Sequence (AMS). If the transition into PE_SRC_Ready is the result of Protocol Error that has not caused a Soft Reset (see Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram") then the notification to the Protocol Layer of the end of the AMS Shall Not be sent since there is a Message to be processed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 831 On entry to the PE_SRC_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, the Policy Engine Shall:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). On entry to the PE_SRC_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SourcePPSCommTimer. On entry to the PE_SRC_Ready state if the current Explicit Contract is for EPR Mode, then the Policy Engine Shall do the following:  Initialize and run the SourceEPRKeepAliveTimer. On exit from the PE_SRC_Ready, if the Source is initiating an AMS, then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed or  A Get_Source_Cap Message is received, and the Source is in SPR Mode or  An EPR_Get_Source_Cap Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received, and the Source is in SPR Mode or  An EPR_Request Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap state when:  The Device Policy Manager asks for the Sink Capabilities. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Source is operating as an SPR PPS and the SourcePPSCommTimer Timer times-out or  The Source is in EPR Mode and the SourceEPRKeepAliveTimer Timer times-out. The Policy Engine Shall transition to the PE_SRC_EPR_Keep_Alive state when:  An EPR_KeepAlive Message is received. The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap State when:  In EPR Mode and a Get_Source_Cap Message is received or  In SPR Mode and an EPR_Get_Source_Cap Message is received. 8.3.3.2.7 PE_SRC_Disabled State In the PE_SRC_Disabled state the PD Source supplies default power and is unresponsive to USB Power Delivery messaging, but not to Hard Reset Signaling. 8.3.3.2.8 PE_SRC_Capability_Response State The Policy Engine Shall enter the PE_SRC_Capability_Response state if there is a Request received from the Sink that cannot be met based on the present capabilities. When the present Explicit Contract is not within the present capabilities it is regarded as Invalid and a Hard Reset will be triggered. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall request the Protocol Layer to send one of the following: Page 832 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Reject Message - if the request cannot be met or the present Explicit Contract is Invalid.  Wait Message - if the request could be met later from the Power Reserve. A Wait Message Shall Not be sent if the present Explicit Contract is Invalid. The Policy Engine Shall transition to the PE_SRC_Ready state when:  There is an Explicit Contract and  A Reject Message has been sent and the present Explicit Contract is still Valid or  A Wait Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  There is an Explicit Contract and  The Reject Message has been sent and the present Explicit Contract is Invalid (i.e., the Sink had to request a new value so instead we will return to USB Default Operation). The Policy Engine Shall transition to the PE_SRC_Wait_New_Capabilities state when:  There is no Explicit Contract and  A Reject Message has been sent or  A Wait Message has been sent. 8.3.3.2.9 PE_SRC_Hard_Reset State The Policy Engine Shall transition to the PE_SRC_Hard_Reset state from any state when:  Hard Reset request from Device Policy Manager or  In EPR Mode and a Request Message is received or  EPR Capable and in SPR Mode and an EPR_Request Message is received. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall:  request the generation of Hard Reset Signaling by the PHY Layer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out.  initialize and run the PSHardResetTimer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when:  The PSHardResetTimer times out. 8.3.3.2.10 PE_SRC_Hard_Reset_Received State The Policy Engine Shall transition from any state to the PE_SRC_Hard_Reset_Received state when:  Hard Reset Signaling is detected. On entry to the PE_SRC_Hard_Reset_Received state the Policy Engine Shall:  initialize and run the PSHardResetTimer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 833  The PSHardResetTimer times out. 8.3.3.2.11 PE_SRC_Transition_to_default State On entry to the PE_SRC_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the power supply Shall Hard Reset (see Section 7.1.5, "Response to Hard Resets").  request a reset of the local hardware  request the Device Policy Manager to set the Port Data Role to DFP and turn off VCONN. On exit from the PE_SRC_Transition_to_default state the Policy Engine Shall:  request the Device Policy Manager to turn on VCONN  inform the Protocol Layer that the Hard Reset is complete. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Device Policy Manager indicates that the power supply has reached the default level. 8.3.3.2.12 PE_SRC_Get_Sink_Cap State In this state the Policy Engine, due to a request from the Device Policy Manager, Shall request the capabilities from the Attached Sink. On entry to the PE_SRC_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SRC_Ready state when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. 8.3.3.2.13 PE_SRC_Wait_New_Capabilities State In this state the Policy Engine has been unable to Negotiate an Explicit Contract and is waiting for new Capabilities from the Device Policy Manager. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed. 8.3.3.2.14 PE_SRC_EPR_Keep_Alive State On entry to the PE_SRC_EPR_Keep_Alive State the Policy Engine Shall send a EPR_KeepAlive_Ack Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_KeepAlive_Ack Message has been sent. Page 834 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.2.15 8.3.3.2.15PE_SRC_Give_Source_Cap State  On entry to the PE_SRC_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Source Capabilities Message has been successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 835 8.3.3.3 Policy Engine Sink Port State Diagram Figure 8.133, "Sink Port State Diagram" below shows the state diagram for the Policy Engine in a Sink Port. The following sections describe operation in each of the states. Figure 8.133 Sink Port State Diagram 1) Source Capabilities Messages received in States other than PE_SNK_Wait_for_Capabilities, PE_SNK_Ready or PE_SNK_Get_Source_Cap constitute a Protocol Error. 2) The SinkRequestTimer Should Not be stopped if a Ping (Deprecated) Message is received in the PE_SNK_Ready state since it represents the maximum time between requests after a Wait Message which is not reset by a Ping (Deprecat- ed) Message. 3) During a Hard Reset the Source voltage will transition to vSafe0V and then transition to vSafe5V. Sinks need to ensure that VBUS present is not indicated until after the Source has completed the Hard Reset process by detecting both of these transitions. New power required | SinkRequestTimer Timeout | SinkPPSPeriodicTimer Timeout Start Explicit Contract & (Reject message received | Wait message received) Hard reset signalling received Power Sink at default Protocol Layer Reset Hard Reset complete VBUS 6 present3 ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source_Capabilities Message received))1 Device Policy Manager Response received Accept message received PS_RDY message received Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink capabilities message sent ((SinkWaitCapTimer timeout | PSTransitionTimer timeout) & (HardResetCounter ” nHardResetCount)) | Hard Reset request from Device Policy Manager | EPR Mode & (EPR_Source _Capabilites message with An EPR PDO in positions 1..7 | Source_Capabilities Message not requested by Get_Source_caps) PE_SNK_Startup Actions on entry: Reset Protocol Layer Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected SenderResponseTimer Timeout PE_SNK_Discovery Actions on entry: Wait for VBUS 6 Power = Default (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Wait_for_Capabilities Actions on entry: Initialize and run SinkWaitCapTimer Power = Default (5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Evaluate_Capability Actions on entry: Reset HardResetCounter to zero. Ask Device Policy Manager to evaluate the options based on supplied capabilities, any Power Reserve that it needs, and respond indicating the selected capability and, Optionally, a “Capability Mismatch”. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Select_Capability Actions on entry: Send Request based on Device Policy Manager response: • Request from present capabilities • Optionally Indicate that other capabilities would be preferred (“Capability Mismatch”) Initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Transition_Sink Actions on entry: Initialize and run PSTransitionTimer Power = transition PD = Connected Actions on exit: Request Device Policy Manager transitions sink power supply to new power (if required) PE_SNK_Ready Actions on entry: Initialize and run SinkRequestTimer2 (on receiving Wait) Initialize and run DiscoverIdentityTimer4 Initialize and run the SinkPPSPeriodicTimer5 In EPR Mode Initialize and run the SinkEPRKeepAliveTimer8 If Sink supports Fast Role Swap send Get_Sink_Cap Message7 Power = Explicit Contract PD = Connected PE_SNK_Give_Sink_Cap Actions on entry: Get present sink capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected PE_SNK_Hard_Reset Actions on entry: Generate Hard Reset signalling. Increment HardResetCounter. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SNK_Transition_to_default Actions on entry: Request Device Policy Manager to request power sink transition to default Reset local HW Set Port Data Role to UFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected Actions on exit: Inform Protocol Layer Hard Reset complete no Explicit Contract & (Reject message received | Wait message received) ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source Capabilities Message))1 Actions on exit: If the Sink is initiating an AMS then notify the Protocol Layer that the first Message in the AMS will follow. Protocol Error PE_SNK_EPR_Keep_Alive Actions on entry: Send EPR_KeepAlive Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected SinkEPRKeepAliveTimer Timeout EPR_KeepAlive_Ack Message SenderResponseTimer Timeout PE_SNK_Get_Source_Cap Actions on entry: If SPR Mode capabilities requested send Get_Source_Cap Message If EPR Mode capabilities requested send EPR_Get_Source_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get source capabilities request from Device Policy Manager (EPR Mode & SPR Source Capabilities requested & Source_Capabilities Message received) | (SPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message received) | SenderResponseTimer timeout Actions on exit: Pass Source capabilities/outcome to Device Policy Manager (SPR Mode & SPR Source Capabilities requested & Source_Capabilities Message) | (EPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message) Page 836 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 5) The SinkPPSPeriodicTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sinks that do not support PPS do not need to implement the SinkPPSPeriodicTimer. 6) A Sink that is a VPD May use VCONN as a proxy for VBUS. 7) To be sent once, and only required if Fast Role Swap is supported by the Sink. 8.3.3.3.1 PE_SNK_Startup State PE_SNK_Startup Shall be the starting state for a Sink Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). Once the reset process completes, the Policy Engine Shall transition to the PE_SNK_Discovery state. 8.3.3.3.2 PE_SNK_Discovery State In the PE_SNK_Discovery state the Sink Policy Engine waits for VBUS to be present. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Device Policy Manager indicates that VBUS has been detected. 8.3.3.3.3 PE_SNK_Wait_for_Capabilities State On entry to the PE_SNK_Wait_for_Capabilities state the Policy Engine Shall initialize and start the SinkWaitCapTimer. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  The Sink is in SPR Mode and a Source_Capabilities Message is received or  The Sink is in EPR Mode and an EPR_Source_Capabilities Message is received. When the SinkWaitCapTimer times out, the Policy Engine will perform a Hard Reset. 8.3.3.3.4 PE_SNK_Evaluate_Capability State The PE_SNK_Evaluate_Capability state is first entered when the Sink receives its first Source_Capabilities Message from the Source. At this point the Sink knows that it is Attached to and communicating with a PD capable Source. On entry to the PE_SNK_Evaluate_Capability state the Policy Engine Shall request the Device Policy Manager to evaluate the supplied Source Capabilities based on Local Policy. The Device Policy Manager Shall indicate to the Policy Engine the new power level required, selected from the present offered capabilities. The Device Policy Manager Shall also indicate to the Policy Engine a Capabilities Mismatch if the offered power does not meet the device's requirements. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A response is received from the Device Policy Manager. 8.3.3.3.5 PE_SNK_Select_Capability State On entry to the PE_SNK_Select_Capability state the Policy Engine Shall request the Protocol Layer to send a response Message, based on the evaluation from the Device Policy Manager. The Message Shall be one of the following:  A Request from the offered Source Capabilities. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 837  A Request from the offered Source Capabilities with an indication that another power level would be preferred (Capability Mismatch bit set). When in SPR Mode a Request Message Shall be sent. When in EPR Mode an EPR_Request Message Shall be sent. The Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Transition_Sink state when:  An Accept Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  There is no Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Ready state when:  There is an Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs. 8.3.3.3.6 PE_SNK_Transition_Sink State On entry to the PE_SNK_Transition_Sink state the Policy Engine Shall initialize and run the PSTransitionTimer (timeout will lead to a Hard Reset see Section 8.3.3.3.8, "PE_SNK_Hard_Reset State" and Shall then request the Device Policy Manager to transition the Sink's power supply to the new power level. Note: If there is no power level change the Device Policy Manager Should Not affect any change to the power supply. On exit from the PE_SNK_Transition_Sink state the Policy Engine Shall request the Device Policy Manager to transition the Sink's power supply to the new power level. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A PS_RDY Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.3.7 PE_SNK_Ready State In the PE_SNK_Ready state the PD Sink Shall be operating at a stable power level with no ongoing Negotiation. It Shall respond to requests from the Source, events from the Device Policy Manager. On entry to the PE_SNK_Ready state as the result of a wait the Policy Engine Should do the following:  Initialize and run the SinkRequestTimer. On entry to the PE_SNK_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, then the Policy Engine Shall do the following:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). Page 838 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SinkPPSPeriodicTimer. On entry to the PE_SNK_Ready state if the Sink supports Fast Role Swap, then the Policy Engine Shall do the following:  Send a Get_Sink_Cap Message. On exit from the PE_SNK_Ready state, if the transition is as a result of a DPM request to start a new Atomic Message Sequence (AMS) then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  In SPR Mode and a Source_Capabilities Message is received or  In EPR Mode and an EPR_Source_Capabilities Message is received. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A new power level is requested by the Device Policy Manager or  A SinkRequestTimer timeout occurs or  A SinkPPSPeriodicTimer timeout occurs. The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap state when:  Get_Sink_Cap Message is received or  EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap state when:  The Device Policy Manager requests an update of the remote Source Capabilities. The Policy Engine Shall transition to the PE_SNK_EPR_Keep_Alive state when:  The SinkEPRKeepAliveTimer timeouts out. 8.3.3.3.8 PE_SNK_Hard_Reset State The Policy Engine Shall transition to the PE_SNK_Hard_Reset state from any state when:  (PSTransitionTimer times out) and  (HardResetCounter ≤ nHardResetCount)) |  Hard Reset request from Device Policy Manager or  In EPR Mode and  An EPR_Source_Capabilities Message is received with an EPR (A)PDO in object positions 1…7 or  A Source_Capabilities Message is received that has not been requested using a Get_Source_Cap Message. The Policy Engine May transition to the PE_SNK_Hard_Reset state from any state when:  SinkWaitCapTimer times out Note: If the SinkWaitCapTimer times out and the HardResetCounter is greater than nHardResetCount the Sink Shall assume that the Source is non-responsive. Note: The HardResetCounter is reset on a power cycle or Detach. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 839 On entry to the PE_SNK_Hard_Reset state the Policy Engine Shall request the generation of Hard Reset Signaling by the PHY Layer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SNK_Transition_to_default state when:  The Hard Reset is complete. 8.3.3.3.9 PE_SNK_Transition_to_default State The Policy Engine Shall transition from any state to PE_SNK_Transition_to_default state when:  Hard Reset Signaling is detected. When Hard Reset Signaling is received or transmitted then the Policy Engine Shall transition from any state to PE_SNK_Transition_to_default. This state can also be entered from the PE_SNK_Hard_Reset state. On entry to the PE_SNK_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the Sink Shall transition to default  request a reset of the local hardware  request the Device Policy Manager that the Port Data Role is set to UFP. The Policy Engine Shall transition to the PE_SNK_Startup state when:  The Device Policy Manager indicates that the Sink has reached the default level. 8.3.3.3.10 PE_SNK_Give_Sink_Cap State  On entry to the PE_SNK_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Sink_Capabilities Message has been successfully sent. 8.3.3.3.11 PE_SNK_EPR_Keep_Alive On entry to the PE_SNK_EPR_Keep_Alive State the Policy Engine Shall send an EPR_KeepAlive Message and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A EPR_KeepAlive_Ack Message is received. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The SenderResponseTimer times out. 8.3.3.3.12 PE_SNK_Get_Source_Cap State  On entry to the PE_SNK_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. Page 840 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On exit from the PE_SNK_Get_Source_Cap State the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SNK_Ready state when:  In EPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In SPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability State when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 841 8.3.3.4 SOP Soft Reset and Protocol Error State Diagrams 8.3.3.4.1 SOP Source Port Soft Reset and Protocol Error State Diagram Figure 8.134, "SOP Source Port Soft Reset and Protocol Error State Diagram" below shows the state diagram for the Policy Engine in a Source Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.134 SOP Source Port Soft Reset and Protocol Error State Diagram 8.3.3.4.1.1 PE_SRC_Send_Soft_Reset State The PE_SRC_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during a Non-interruptible AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response or  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  The Source is in the PE_SRC_Send_Capabilities state, there is a Source_Capabilities Message sending failure on SOP (without a GoodCRC Message) and the Source is not presently Attached (as indicated in Figure 8.132, "Source Port State Diagram"). In this case, the PE_SRC_Discovery state is entered (see Section 8.3.3.2.2, "PE_SRC_Discovery State").  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.2, "Policy Engine Source Port State Diagram"). In this case Hard Reset Signaling will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case USB Type-C Error Recovery will be triggered directly.  During a Data Role Swap when there is a mismatch in the Port Data Role field (see Section 6.2.1.1.6, "Port Data Role"). In this case USB Type-C Error Recovery will be triggered directly. PE_SRC_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept message Received from SOP Accept message Sent to SOP Soft Reset message Received on SOP PE_SRC_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SRC_Send_Capabilities Transmission Error indication from Protocol Layer PE_SRC_Ready In Explicit Contract & Protocol Error2 before first Message in AMS sent (no GoodCRC received) PE_SRC_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message received on SOP will result in a Not_Supported Message response being generated on SOP (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Source during the EPR Mode entry process. Page 842 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SRC_Ready state where the Message received will be handled as if it had been received in the PE_SRC_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. On entry to the PE_SRC_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message to the Sink on SOP, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.1.2 PE_SRC_Soft_Reset State The PE_SRC_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SRC_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state (see Section 8.3.3.2.3, "PE_SRC_Send_Capabilities State") when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 843 8.3.3.4.2 SOP Sink Port Soft Reset and Protocol Error State Diagram Figure 8.135, "Sink Port Soft Reset and Protocol Error Diagram" below shows the state diagram for the Policy Engine in a Sink Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.135 Sink Port Soft Reset and Protocol Error Diagram 8.3.3.4.2.1 PE_SNK_Send_Soft_Reset State The PE_SNK_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during an AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response.  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). In this case a Hard Reset will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case a Hard Reset will be triggered directly.  During a Data Role Swap when the DFP/UFP Data Roles are changing. In this case USB Type-C Error Recovery will be triggered directly. Note: Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SNK_Ready state where the Message received will be handled as if it had been received in the PE_SNK_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. PE_SNK_Send_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Soft Reset Message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept Message Received on SOP Accept Message Sent to SOP Soft Reset Message Received on SOP PE_SNK_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Accept Message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SNK_Wait_for_Capabilities Transmission Error indication from Protocol Layer PE_SNK_Ready In Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message will result in a Not_Supported Message response being generated (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Sink during the EPR Mode entry process. Page 844 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP to the Source, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.2.2 PE_SNK_Soft_Reset State The PE_SNK_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SNK_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 845 8.3.3.5 Data Reset State Diagrams 8.3.3.5.1 DFP Data_Reset Message State Diagrams Figure 8.136, "DFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a DFP. Figure 8.136 DFP Data_Reset Message State Diagram 8.3.3.5.1.1 PE_DDR_Send_Data_Reset State The PE_DDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_DDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and start the SenderResponseTimer. On exit from the PE_DDR_Send_Data_Reset State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been received and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been received and PE_DDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and start SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_DDR_Wait_for_VCONN_Off Actions on entry: Initialize and start VCONNDischargeTimer Power = Explicit Contract PD = connected Accept Message Received & Not VCONN Source VCONNDischargeTimer Timeout | Protocol Error PS_RDY Received PE_DDR_Perform_Data_Reset Actions on entry: Tell Device Policy Manager to perform Data Reset Power = Explicit Contract PD = connected PE_SRC_Ready or PE_SNK_Ready (DFP) Data Reset process is complete Accept Message Sent & Not VCONN Source Protocol Error DataResetFailTimer Timeout | Protocol Error Actions on exit: Stop DataResetFailTimer Send Data_Reset_Complete Message Actions on exit: Initialize and start DataResetFailTimer1 Actions on exit: Initialize and start DataResetFailTimer1 1) Note that the DataResetFailTimer Shall continue to run in every state until it is stopped or times out. Page 846 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A SenderResponseTimer timeout occurs or  A Protocol Error occurs. 8.3.3.5.1.2 PE_DDR_Data_Reset_Received State The PE_DDR_Data_Reset_Received State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_DDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_DDR_Data_Reset_Received State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been sent and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been sent and  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.1.3 PE_DDR_Wait_For_VCONN_Off State On entry to the PE_DDR_Wait_For_VCONN_Off State the Policy Engine Shall initialize and start the VCONNDischargeTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  A PS_RDY Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The VCONNDischargeTimer has timed out or  A Protocol Error occurs. 8.3.3.5.1.4 PE_DDR_Perform_Data_Reset State On entry to the PE_DDR_Perform_Data_Reset State the Policy Engine Shall request the Device Policy Manager to complete the Data Reset process as defined in Section 6.3.14, "Data_Reset Message". On exit from the PE_DDR_Perform_Data_Reset State the Policy Engine Shall stop the DataResetFailTimer and send a Data_Reset_Complete Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the DFP's Power Role when:  The DPM indicates that Data Reset process is complete (see Section 6.3.14, "Data_Reset Message"). The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailTimer times out  A Protocol Error occurs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 847 8.3.3.5.2 UFP Data_Reset Message State Diagrams Figure 8.137, "UFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a UFP. Figure 8.137 UFP Data_Reset Message State Diagram 8.3.3.5.2.1 PE_UDR_Send_Data_Reset State The PE_UDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_UDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and run the SenderResponseTimer. On exit from the PE_UDR_Send_Data_Reset State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been received and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been received and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when: PE_UDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (UFP) PE_UDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_UDR_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = connected PE_UDR_Send_Ps_Rdy Actions on entry: Send PS_RDY Message Power = Explicit Contract PD = connected VCONN Off1 PE_SRC_Ready or PE_SNK_Ready (UFP) Accept Message Received & Not VCONN Source PS_RDY Message Sent Accept Message Sent & Not VCONN Source Protocol Error PE_UDR_Wait_For_Data_Reset_Complete Actions on entry: Wait for Data_Reset_Complete Message Power = Explicit Contract PD = connected Data_Reset_Complete Message received Protocol Error Protocol Error DataResetFailUFPTimer Timeout2 | Protocol Error Actions on exit: Stop DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 1) VCONN Shall be fully discharged see Section 7.1.15 “Vconn Power Cycle”. 2) Note that the DataResetFailUFPTimer Shall continue to run in every state until it is stopped or times out. Page 848 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The SenderResponseTimer has timed out or  A Protocol Error occurs. 8.3.3.5.2.2 PE_UDR_Data_Reset_Received State The PE_UDR_Data_Reset_Received State Shall be entered from either the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_UDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_UDR_Data_Reset_Received State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been sent and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been sent and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.3 PE_UDR_Turn_Off_VCONN State On entry to the PE_UDR_Turn_Off_VCONN State the Policy Engine Shall request the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition to the PE_UDR_Send_Ps_Rdy State when:  The DPM indicates that VCONN has been turned off (VCONN below vRaReconnect see [USB Type-C 2.4]). The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.4 PE_UDR_Send_Ps_Rdy State On entry to the PE_UDR_Send_Ps_Rdy State the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.5 PE_UDR_Wait_For_Data_Reset_Complete State On entry to the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall wait for the Data_Reset_Complete Message. On exit from the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall stop the DataResetFailUFPTimer. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the UFP's Power Role when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 849  The Data_Reset_Complete Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailUFPTimer times out or  A Protocol Error occurs. Page 850 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6 Not Supported Message State Diagrams 8.3.3.6.1 Source Port Not Supported Message State Diagram Figure 8.138, "Source Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Source Port. Figure 8.138 Source Port Not Supported Message State Diagram 8.3.3.6.1.1 PE_SRC_Send_Not_Supported State The PE_SRC_Send_Not_Supported state Shall be entered from the PE_SRC_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SRC_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SRC_Send_Not_Supported state (from the PE_SRC_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.1.2 PE_SRC_Not_Supported_Received State The PE_SRC_Not_Supported_Received state Shall be entered from the PE_SRC_Ready state when a Not_Supported Message is received. On entry to the PE_SRC_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.1.3 PE_SRC_Chunk_Received State The PE_SRC_Chunk_Received state Shall be entered from the PE_SRC_Ready state as a result of an Unsupported Message being received in the PE_SRC_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). PE_SRC_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SRC_Ready PE_SRC_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SRC_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SRC_Ready state directly (see also Section 8.3.3.4.1 “SOP Source Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 851 On entry to the PE_SRC_Chunk_Received state (from the PE_SRC_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SRC_Send_Not_Supported when:  The ChunkingNotSupportedTimer has timed out. Page 852 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6.2 Sink Port Not Supported Message State Diagram Figure 8.139, "Sink Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Sink Port. Figure 8.139 Sink Port Not Supported Message State Diagram 8.3.3.6.2.1 PE_SNK_Send_Not_Supported State The PE_SNK_Send_Not_Supported state Shall be entered from the PE_SNK_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SNK_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Send_Not_Supported state (from the PE_SNK_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.2.2 PE_SNK_Not_Supported_Received State The PE_SNK_Not_Supported_Received state Shall be entered from the PE_SNK_Ready state when a Not_Supported Message is received. On entry to the PE_SNK_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.2.3 PE_SNK_Chunk_Received State The PE_SNK_Chunk_Received state Shall be entered from the PE_SNK_Ready state as a result of an Unsupported Message being received in the PE_SNK_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Chunk_Received state (from the PE_SNK_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SNK_Send_Not_Supported when: PE_SNK_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SNK_Ready PE_SNK_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SNK_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SNK_Ready state directly (see also Section 8.3.3.4.2 “SOP Sink Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 853  The ChunkingNotSupportedTimer has timed out. Page 854 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7 Alert State Diagrams 8.3.3.7.1 Source Port Source Alert State Diagram Figure 8.140, "Source Port Source Alert State Diagram" shows the state diagram for an Alert Message sent by a Source Port. Figure 8.140 Source Port Source Alert State Diagram 8.3.3.7.1.1 PE_SRC_Send_Source_Alert State The PE_SRC_Send_Source_Alert state Shall be entered from the PE_SRC_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SRC_Send_Source_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SRC_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.1.2 PE_SRC_Wait_for_Get_Status State On entry to the PE_SRC_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The SenderResponseTimer times out. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 855 8.3.3.7.2 Sink Port Source Alert State Diagram Figure 8.141, "Sink Port Source Alert State Diagram" shows the state diagram for an Alert Message received by a Sink Port. Figure 8.141 Sink Port Source Alert State Diagram 8.3.3.7.2.1 PE_SNK_Source_Alert_Received State The PE_SNK_Source_Alert_Received state Shall be entered from the PE_SNK_Ready state when an Alert Message is received. On entry to the PE_SNK_Source_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SNK_Ready State (see Figure 8.133, "Sink Port State Diagram") when:  The DPM does not request status. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Page 856 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7.3 Sink Port Sink Alert State Diagram Figure 8.142, "Sink Port Sink Alert State Diagram" shows the state diagram for an Alert Message sent by a Sink Port. Figure 8.142 Sink Port Sink Alert State Diagram 8.3.3.7.3.1 PE_SNK_Send_Sink_Alert State The PE_SNK_Send_Sink_Alert state Shall be entered from the PE_SNK_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SNK_Send_Sink_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SNK_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.3.2 PE_SNK_Wait_for_Get_Status State On entry to the PE_SNK_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to the PE_SNK_Ready (see Figure 8.133, "Sink Port State Diagram") when:  The SenderResponseTimer times out. PE_SNK_Send_Sink_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Sink alert condition Alert Message sent PE_SNK_Ready SenderResponseTimer Timeout PE_SNK_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 857 8.3.3.7.4 Source Port Sink Alert State Diagram Figure 8.143, "Source Port Sink Alert State Diagram" shows the state diagram for an Alert Message received by a Source Port. Figure 8.143 Source Port Sink Alert State Diagram 8.3.3.7.4.1 PE_SRC_Sink_Alert_Received State The PE_SRC_Sink_Alert_Received state Shall be entered from the PE_SRC_Ready state when an Alert Message is received. On entry to the PE_SRC_Sink_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The DPM does not request status. PE_SRC_Sink_Alert_Received Actions on entry: Inform DPM of the detail of the alert Power = Explicit Contract PD = connected Sink Alert Message received DPM does not request status PE_SRC_Ready PE_Get_Status DPM Requests Status Page 858 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8 Source/Sink Capabilities Extended State Diagrams 8.3.3.8.1 Sink Port Get Source Capabilities Extended State Diagram Figure 8.144, "Sink Port Get Source Capabilities Extended State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.144 Sink Port Get Source Capabilities Extended State Diagram 8.3.3.8.1.1 PE_SNK_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 859 8.3.3.8.2 Source Give Source Capabilities Extended State Diagram Figure 8.145, "Source Give Source Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.145 Source Give Source Capabilities Extended State Diagram 8.3.3.8.2.1 PE_SRC_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_SRC_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SRC_Ready PE_SRC_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 860 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8.3 Source Port Get Sink Capabilities Extended State Diagram Figure 8.146, "Source Port Get Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.146 Source Port Get Sink Capabilities Extended State Diagram 8.3.3.8.3.1 PE_SRC_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Sink_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_SRC_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass sink extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 861 8.3.3.8.4 Sink Give Sink Capabilities Extended State Diagram Figure 8.147, "Sink Give Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.147 Sink Give Sink Capabilities Extended State Diagram 8.3.3.8.4.1 PE_SNK_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_SNK_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Sink_Capabilities_Extended Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SNK_Ready PE_SNK_Give_Sink_Cap_Ext Actions on entry: Get present extended Sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 862 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.9 Source Information State Diagrams 8.3.3.9.1 Sink Port Get Source Information State Diagram Figure 8.148, "Sink Port Get Source Information State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.148 Sink Port Get Source Information State Diagram 8.3.3.9.1.1 PE_SNK_Get_Source_Info State The Policy Engine Shall transition to the PE_SNK_Get_Source_Info state, from the PE_SNK_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Info Message is received  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 863 8.3.3.9.2 Source Give Source Information State Diagram Figure 8.149, "Source Give Source Information State Diagram" shows the state diagram for a Source on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.149 Source Give Source Information State Diagram 8.3.3.9.2.1 PE_SRC_Give_Source_Info State The Policy Engine Shall transition to the PE_SRC_Give_Source_Info state, from the PE_SRC_Ready state, when a Get_Source_Info Message is received. On entry to the PE_SRC_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SRC_Ready PE_SRC_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 864 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10 Status State Diagrams 8.3.3.10.1 Get Status State Diagram Figure 8.150, "Get Status State Diagram" shows the state diagram for a Port on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Status. See also Section 6.5.2, "Status Message". Figure 8.150 Get Status State Diagram 8.3.3.10.1.1 PE_Get_Status State The Policy Engine Shall transition to the PE_Get_Status state, from the PE_SRC_Ready or PE_SNK_Ready States, due to a request to get the Port Partner or Cable Plug's status from the Device Policy Manager. On entry to the PE_Get_Status state the Policy Engine Shall send a Get_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram" or Figure 8.133, "Sink Port State Diagram") when:  A Status Message is received  Or SenderResponseTimer times out. get status request from Device Policy Manager Status Message received | SenderResponseTimer Timeout PE_SNK_Ready, PE_SRC_Ready PE_Get_Status Actions on entry: Send Get_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 865 8.3.3.10.2 Give Status State Diagram Figure 8.151, "Give Status State Diagram" shows the state diagram for a Source on receiving a Get_Status Message. See also Section 6.5.2, "Status Message". Figure 8.151 Give Status State Diagram 8.3.3.10.2.1 PE_Give_Status State The Policy Engine Shall transition to the PE_Give_Status state, from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States, when a Get_Status Message is received. On entry to the PE_Give_Status state the Policy Engine Shall request the present Source status from the Device Policy Manager and then send a Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram"and Figure 8.203, "Cable Ready State Diagram") when:  The Status Message has been successfully sent. Get_Status Message received Status Message sent PE_SRC_Ready, PE_SNK_Ready, PE_CBL_Ready PE_Give_Status Actions on entry: Get present Status from Device Policy Manager Send Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 866 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10.3 Sink Port Get Source PPS Status State Diagram Figure 8.152, "Sink Port Get Source PPS Status State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source status when operating as a PPS. See also Section 6.5.10, "PPS_Status Message". Figure 8.152 Sink Port Get Source PPS Status State Diagram 8.3.3.10.3.1 PE_SNK_Get_PPS_Status State The Policy Engine Shall transition to the PE_SNK_Get_PPS_Status state, from the PE_SNK_Ready state, due to a request to get the remote Source PPS status from the Device Policy Manager. On entry to the PE_SNK_Get_PPS_Status state the Policy Engine Shall send a Get_PPS_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_PPS_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A PPS_Status Message is received  Or SenderResponseTimer times out. get PPS status request from Device Policy Manager PPS_Status Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_PPS_Status Actions on entry: Send Get_PPS_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 867 8.3.3.10.4 Source Give Source PPS Status State Diagram Figure 8.153, "Source Give Source PPS Status State Diagram" shows the state diagram for a Source on receiving a Get_PPS_Status Message. See also Section 6.5.10, "PPS_Status Message". Figure 8.153 Source Give Source PPS Status State Diagram 8.3.3.10.4.1 PE_SRC_Give_PPS_Status State The Policy Engine Shall transition to the PE_SRC_Give_PPS_Status state, from the PE_SRC_Ready state, when a Get_PPS_Status Message is received. On entry to the PE_SRC_Give_PPS_Status state the Policy Engine Shall request the present Source PPS status from the Device Policy Manager and then send a PPS_Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The PPS_Status Message has been successfully sent. Get_PPS_Status Message received PPS_Status Message sent PE_SRC_Ready PE_SRC_Give_PPS_Status Actions on entry: Get present Source PPS status from Device Policy Manager Send PPS_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 868 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.11 Battery Capabilities State Diagrams 8.3.3.11.1 Get Battery Capabilities State Diagram Figure 8.154, "Get Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery capabilities for a specified Battery. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.154 Get Battery Capabilities State Diagram 8.3.3.11.1.1 PE_Get_Battery_Cap State The Policy Engine Shall transition to the PE_Get_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery capabilities, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Cap state the Policy Engine Shall send a Get_Battery_Cap Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Capabilities Message is received  Or SenderResponseTimer times out. get Battery capabilities request from Device Policy Manager Battery_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Cap Actions on entry: Send Get_Battery_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 869 8.3.3.11.2 Give Battery Capabilities State Diagram Figure 8.155, "Give Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Cap Message. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.155 Give Battery Capabilities State Diagram 8.3.3.11.2.1 PE_Give_Battery_Cap State The Policy Engine Shall transition to the PE_Give_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Cap Message is received. On entry to the PE_Give_Battery_Cap state the Policy Engine Shall request the present Battery capabilities, for the requested Battery, from the Device Policy Manager and then send a Battery_Capabilities Message based on these capabilities. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Capabilities Message has been successfully sent. Get_Battery_Cap Message received Battery_Capabilities Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Cap Actions on entry: Get present Battery capabilities from Device Policy Manager Send Battery_Capabilities Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 870 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.12 Battery Status State Diagrams 8.3.3.12.1 Get Battery Status State Diagram Figure 8.156, "Get Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery status for a specified Battery. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.156 Get Battery Status State Diagram 8.3.3.12.1.1 PE_Get_Battery_Status State The Policy Engine Shall transition to the PE_Get_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery status, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Status state the Policy Engine Shall send a Get_Battery_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Status Message is received  Or SenderResponseTimer times out. get Battery status request from Device Policy Manager Battery_Status Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Status Actions on entry: Send Get_Battery_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 871 8.3.3.12.2 Give Battery Status State Diagram Figure 8.157, "Give Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Status Message. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.157 Give Battery Status State Diagram 8.3.3.12.2.1 PE_Give_Battery_Status State The Policy Engine Shall transition to the PE_Give_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Status Message is received. On entry to the PE_Give_Battery_Status state the Policy Engine Shall request the present Battery status, for the requested Battery, from the Device Policy Manager and then send a Battery_Status Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Status Message has been successfully sent. Get_Battery_Status Message received Battery_Status Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Status Actions on entry: Get present Battery status from Device Policy Manager Send Battery_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 872 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.13 Manufacturer Information State Diagrams 8.3.3.13.1 Get Manufacturer Information State Diagram Figure 8.158, "Get Manufacturer Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Manufacturer Information. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.158 Get Manufacturer Information State Diagram 8.3.3.13.1.1 PE_Get_Manufacturer_Info State The Policy Engine Shall transition to the PE_Get_Manufacturer_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Manufacturer_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Manufacturer_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Manufacturer_Info Message is received  Or SenderResponseTimer times out. get manufacturer information request from Device Policy Manager Manufacturer_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Manfacturer_Info Actions on entry: Send Get_Manfacturer_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Manufacturer Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 873 8.3.3.13.2 Give Manufacturer Information State Diagram Figure 8.159, "Give Manufacturer Information State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Manufacturer_Info Message. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.159 Give Manufacturer Information State Diagram 8.3.3.13.2.1 PE_Give_Manufacturer_Info State The Policy Engine Shall transition to the PE_Give_Manufacturer_Info state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Manufacturer_Info Message is received. On entry to the PE_Give_Manufacturer_Info state the Policy Engine Shall request the manufacturer information from the Device Policy Manager and then send a Manufacturer_Info Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Manufacturer_Info Message has been successfully sent. Get_Manufacturer_Info Message received Manufacturer_Info Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Manufacturer_Info Actions on entry: Get present Manufacturer Information from Device Policy Manager Send Manufacturer_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 874 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14 Country Codes and Information State Diagrams 8.3.3.14.1 Get Country Codes State Diagram Figure 8.160, "Get Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Codes. See also Section 6.5.11, "Country_Codes Message". Figure 8.160 Get Country Codes State Diagram 8.3.3.14.1.1 PE_Get_Country_Codes State The Policy Engine Shall transition to the PE_Get_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Country Codes from the Device Policy Manager. On entry to the PE_Get_Country_Codes state the Policy Engine Shall send a Get_Country_Codes Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Codes state the Policy Engine Shall inform the Device Policy Manager of the outcome (Country Codes or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Codes Message is received  Or SenderResponseTimer times out. get country codes request from Device Policy Manager Country_Codes Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Codes Actions on entry: Send Get_Country_Codes Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Codes/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 875 8.3.3.14.2 Give Country Codes State Diagram Figure 8.161, "Give Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Codes Message. See also Section 6.5.11, "Country_Codes Message". Figure 8.161 Give Country Codes State Diagram 8.3.3.14.2.1 PE_Give_Country_Codes State The Policy Engine Shall transition to the PE_Give_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Codes Message is received. On entry to the PE_Give_Country_Codes state the Policy Engine Shall request the country codes from the Device Policy Manager and then send a Country_Codes Message containing these codes. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Codes Message has been successfully sent. Get_Country_Codes Message received Country_Codes Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Codes Actions on entry: Get present Country Codes from Device Policy Manager Send Country_Codes Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 876 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14.3 Get Country Information State Diagram Figure 8.162, "Get Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Information. See also Section 6.5.12, "Country_Info Message". Figure 8.162 Get Country Information State Diagram 8.3.3.14.3.1 PE_Get_Country_Info State The Policy Engine Shall transition to the PE_Get_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Country_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (country information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Info Message is received  Or SenderResponseTimer times out. get country information request from Device Policy Manager Country_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Info Actions on entry: Send Get_Country_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 877 8.3.3.14.4 Give Country Information State Diagram Figure 8.163, "Give Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Info Message. See also Section 6.5.12, "Country_Info Message". Figure 8.163 Give Country Information State Diagram 8.3.3.14.4.1 PE_Give_Country_Info State The Policy Engine Shall transition to the PE_Give_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Info Message is received. On entry to the PE_Give_Country_Info state the Policy Engine Shall request the country information from the Device Policy Manager and then send a Country_Info Message containing this country information. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Info Message has been successfully sent. Get_Country_Info Message received Country_Info Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Info Actions on entry: Get present Country Information from Device Policy Manager Send Country_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 878 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.15 Revision State Diagrams 8.3.3.15.1 Get Revision State Diagram Figure 8.164, "Get Revision State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Revision Information. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.164 Get Revision State Diagram 8.3.3.15.1.1 PE_Get_Revision State The Policy Engine Shall transition to the PE_Get_Revision state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Revision Information from the Device Policy Manager. On entry to the PE_Get_Revision state the Policy Engine Shall send a Get_Revision Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Revision state the Policy Engine Shall inform the Device Policy Manager of the outcome (Revision information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Revision Message is received  Or SenderResponseTimer times out. get Revision request from Device Policy Manager Revision Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Revision Actions on entry: Send Get_Revision Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Revision Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 879 8.3.3.15.2 Give Revision State Diagram Figure 8.165, "Give Revision State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Revision Message. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.165 Give Revision State Diagram 8.3.3.15.2.1 PE_Give_Revision State The Policy Engine Shall transition to the PE_Give_Revision state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Revision Message is received. On entry to the PE_Give_Revision state the Policy Engine Shall request the Revision information from the Device Policy Manager and then send a Revision Message based on this information. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Revision Message has been successfully sent. Get_Revision Message received Revision Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Revision Actions on entry: Get present Revision Information from Device Policy Manager Send Revision Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 880 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.16 Enter_USB Message State Diagrams 8.3.3.16.1 DFP Enter_USB Message State Diagrams Figure 8.166, "DFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message sent by a DFP. Figure 8.166 DFP Enter_USB Message State Diagram 8.3.3.16.1.1 PE_DEU_Send_Enter_USB State The PE_DEU_Send_Enter_USB State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager and the Port is operating as a DFP. On entry to the PE_DEU_Send_Enter_USB State the Policy Engine Shall request the Protocol Layer to send an Enter_USB Message and then initialize and run the SenderResponseTimer. On exit from the PE_DEU_Send_Enter_USB state the Policy Engine Shall inform the Device Policy Manager of the outcome: Accept Message received, Reject Message received, SenderResponseTimer timeout. The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready State depending on the Ports Power Role when:  An Accept Message has been received or  A Wait Message has been received or  A Reject Message has been received  There is a SenderResponseTimer timeout. PE_DEU_Send_Enter_USB Actions on entry: Send Enter_USB Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Enter USB (USB Mode) request from DPM Accept Message Received | Reject Message Received | Wait Message Received | SenderResponseTimer timeout PE_SRC_Ready or PE_SNK_Ready (DFP) Actions on exit: Inform Device Policy Manager of Accept, Wait, Reject or timeout. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 881 8.3.3.16.2 UFP or Cable Plug Enter_USB Message State Diagrams Figure 8.167, "UFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message received by a UFP or Cable Plug. Figure 8.167 UFP Enter_USB Message State Diagram 8.3.3.16.2.1 PE_UEU_Enter_USB_Received State The PE_UEU_Enter_USB_Received state Shall be entered from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when an Enter_USB Message is received and the Port is operating as a UFP or is a Cable Plug. On entry to the PE_UEU_Enter_USB_Received state the Policy Engine Shall inform the Device Policy Manager. The Device Policy Manager responds with an indication of whether the Enter_USB Message is to be accepted or rejected. The Policy Engine Shall send either an Accept Message, a Wait Message or a Reject Message as appropriate. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate when:  Either an Accept Message, a Wait Message or a Reject Message has been sent. PE_SRC_Ready (UFP), PE_SNK_Ready (UFP) or PE_CBL_Ready PE_UEU_Enter_USB_Received Actions on entry: Inform Device Policy Manager of Enter_USB Message Send Accept/Wait/Reject Message based on DPM response Power = Explicit Contract PD = connected Enter_USB Message Received Accept/Wait/Reject Message sent Page 882 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17 Security State Diagrams 8.3.3.17.1 Send Security Request State Diagram Figure 8.168, "Send security request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a security request. See also Section 6.5.8, "Security Messages". Figure 8.168 Send security request State Diagram 8.3.3.17.1.1 PE_Send_Security_Request State The Policy Engine Shall transition to the PE_Send_Security_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a security request from the Device Policy Manager. On entry to the PE_Send_Security_Request state the Policy Engine Shall send a Security_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Security_Request Message has been sent. Send security request from Device Policy Manager Security_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Security_Request Actions on entry: Send Security_Request Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 883 8.3.3.17.2 Send Security Response State Diagram Figure 8.169, "Send security response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Security_Request Message. See also Section 6.5.8, "Security Messages". Figure 8.169 Send security response State Diagram 8.3.3.17.2.1 PE_Send_Security_Response State The Policy Engine Shall transition to the PE_Send_Security_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Security_Request Message is received. On entry to the PE_Send_Security_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Security_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Security_Response Message has been successfully sent. Security_Request Message received Security_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Security_Response Actions on entry: Get present Security response from Device Policy Manager Send Security_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 884 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17.3 Security Response Received State Diagram Figure 8.170, "Security response received State Diagram" shows the state diagram for a Source or Sink on receiving a Security_Response Message. See also Section 6.5.8, "Security Messages". Figure 8.170 Security response received State Diagram 8.3.3.17.3.1 PE_Security_Response_Received State The Policy Engine Shall transition to the PE_Security_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Security_Response Message is received. On entry to the PE_Security_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the security response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Security_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Security_Response_Received Actions on entry: Inform Device Policy Manager of the security response details. Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 885 8.3.3.18 Firmware Update State Diagrams 8.3.3.18.1 Send Firmware Update Request State Diagram Figure 8.171, "Send firmware update request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a firmware update request. See also Section 6.5.9, "Firmware Update Messages". Figure 8.171 Send firmware update request State Diagram 8.3.3.18.1.1 PE_Send_Firmware_Update_Request State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a firmware update request from the Device Policy Manager. On entry to the PE_Send_Firmware_Update_Request state the Policy Engine Shall send a Firmware_Update_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Firmware_Update_Request Message has been sent. Send firmware update request from Device Policy Manager Firmware_Update_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Firmware_Update_Request Actions on entry: Send Firmware_Update_Request Message Power = Explicit Contract PD = Connected Page 886 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.18.2 Send Firmware Update Response State Diagram Figure 8.172, "Send firmware update response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Firmware_Update_Request Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.172 Send firmware update response State Diagram 8.3.3.18.2.1 PE_Send_Firmware_Update_Response State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Firmware_Update_Request Message is received. On entry to the PE_Send_Firmware_Update_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Firmware_Update_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Firmware_Update_Response Message has been successfully sent. Firmware_Update_Request Message received Firmware_Update_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Firmware_Update_Response Actions on entry: Get present firmware update response from Device Policy Manager Send Firmware_Update_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 887 8.3.3.18.3 Firmware Update Response Received State Diagram Figure 8.173, "Firmware update response received State Diagram" shows the state diagram for a Source or Sink on receiving a Firmware_Update_Response Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.173 Firmware update response received State Diagram 8.3.3.18.3.1 PE_Firmware_Update_Response_Received State The Policy Engine Shall transition to the PE_Firmware_Update_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Firmware_Update_Response Message is received. On entry to the PE_Firmware_Update_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the firmware update response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Firmware_Update_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Firmware_Update_Response_Received Actions on entry: Inform Device Policy Manager of the firmware update response details. Power = Explicit Contract PD = Connected Page 888 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19 Dual-Role Port State Diagrams Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition they Shall have the capability to perform a Power Role Swap from the PE_SRC_Ready or PE_SNK_Ready states and Shall return to USB Default Operation on a Hard Reset. The State Diagrams in this section Shall apply to every [USB Type-C 2.4] DRP. 8.3.3.19.1 DFP to UFP Data Role Swap State Diagram Figure 8.174, "DFP to UFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DFP to UFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.174 DFP to UFP Data Role Swap State Diagram 8.3.3.19.1.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Evaluate_Swap state when:  A DR_Swap Message is received and PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DRS_DFP_UFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_DFP_UFP_ Change_to_UFP Actions on entry: Request Device Policy Manager to change port to UFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_DFP_UFP_ Send_Swap Actions on entry: Send Swap DR message Initialize and run SenderResponseTimer Reject message received | Wait message received | SenderResponseTimer timeout PE_DRS_DFP_UFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_DFP_UFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept message sent Port changed to UFP PE_SRC_Ready or PE_SNK_Ready (UFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap message received & in Modal Operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 889  There are no Active Modes (not in Modal Operation). The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.1.2 PE_DRS_DFP_UFP_Evaluate_Swap State On entry to the PE_DRS_DFP_UFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.1.3 PE_DRS_DFP_UFP_Accept_Swap State On entry to the PE_DRS_DFP_UFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  The Accept Message has been sent. 8.3.3.19.1.4 PE_DRS_DFP_UFP_Change_to_UFP State On entry to the PE_DRS_DFP_UFP_Change_to_UFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a DFP to a UFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a UFP. 8.3.3.19.1.5 PE_DRS_DFP_UFP_Send_Swap State On entry to the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  An Accept Message is received. 8.3.3.19.1.6 PE_DRS_DFP_UFP_Reject_Swap State On entry to the PE_DRS_DFP_UFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send: Page 890 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Reject Message if the device is unable to perform a Data Role Swap at this time.  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 891 8.3.3.19.2 UFP to DFP Data Role Swap State Diagram Figure 8.175, "UFP to DFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DRP UFP to DFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.175 UFP to DFP Data Role Swap State Diagram 8.3.3.19.2.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from the either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Evaluate_Swap state when:  A DR_Swap Message is received and  There are no Active Modes (not in Modal Operation). PE_SRC_Ready or PE_SNK_Ready (UFP) PE_DRS_UFP_DFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_UFP_DFP_ Change_to_DFP Actions on entry: Request Device Policy Manager to change port to DFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_UFP_DFP_ Send_Swap Actions on entry: Send Swap DR Message Initialize and run SenderResponseTimer Reject Message received | Wait Message received | SenderResponseTimer timeout PE_DRS_UFP_DFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_UFP_DFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap Message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept Message sent Port changed to DFP PE_SRC_Ready or PE_SNK_Ready (DFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap Message received & in Modal Operation Page 892 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.2.2 PE_DRS_UFP_DFP_Evaluate_Swap State On entry to the PE_DRS_UFP_DFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.2.3 PE_DRS_UFP_DFP_Accept_Swap State On entry to the PE_DRS_UFP_DFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  The Accept Message has been sent. 8.3.3.19.2.4 PE_DRS_UFP_DFP_Change_to_DFP State On entry to the PE_DRS_UFP_DFP_Change_to_DFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a UFP to a DFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a DFP. 8.3.3.19.2.5 PE_DRS_UFP_DFP_Send_Swap State On entry to the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a UFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  An Accept Message is received. 8.3.3.19.2.6 PE_DRS_UFP_DFP_Reject_Swap State On entry to the PE_DRS_UFP_DFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Data Role Swap at this time. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 893  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a UFP and Shall transition to the either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Page 894 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.3 Policy Engine in Source to Sink Power Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.176, "Dual-Role Port in Source to Sink Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Figure 8.176 Dual-Role Port in Source to Sink Power Role Swap State Diagram PE_SRC_Ready PE_PRS_SRC_SNK_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SRC_SNK_ Transition_to_off Actions on entry: Tell Device Policy Manager to turn off power supply Power = Transition to stop sourcing PD = Connected PE_PRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Source off PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SRC_SNK_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected Accept received PE_PRS_SRC_SNK_ Reject_PR_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PS_RDY Message received PE_SNK_Startup PE_PRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Source off PD = Connected Source turned off Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 895 8.3.3.19.3.1 PE_SRC_Ready State The Power Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Evaluate_Swap state when:  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.3.2 PE_PRS_SRC_SNK_Evaluate_Swap State On entry to the PE_PRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK.  Or further evaluation of the Power Role Swap request is needed. 8.3.3.19.3.3 PE_PRS_SRC_SNK_Accept_Swap State On entry to the PE_PRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.3.4 PE_PRS_SRC_SNK_Transition_to_off State On entry to the PE_PRS_SRC_SNK_Transition_to_off state the Policy Engine Shall request the Device Policy Manager to turn off the Source. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that the Source has been turned off. 8.3.3.19.3.5 PE_PRS_SRC_SNK_Assert_Rd State On entry to the PE_PRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.3.6 PE_PRS_SRC_SNK_Wait_Source_on State On entry to the PE_PRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the remote Source is now supplying power. The Policy Engine Shall transition to the ErrorRecovery state when: Page 896 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.3.7 PE_PRS_SRC_SNK_Send_Swap State On entry to the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.3.8 PE_PRS_SRC_SNK_Reject_Swap State On entry to the PE_PRS_SRC_SNK_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SRC_Ready when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 897 8.3.3.19.4 Policy Engine in Sink to Source Power Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.177, "Dual-role Port in Sink to Source Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 898 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.177 Dual-role Port in Sink to Source Power Role Swap State Diagram 8.3.3.19.4.1 PE_SNK_Ready State The Power Role Swap process Shall start only from the PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Evaluate_Swap state when: PE_SNK_Ready PE_PRS_SNK_SRC_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Tell Device Policy Manager to turn off Power Sink. Power = Transition to stop sinking PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SNK_SRC_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SNK_SRC_Accept_Swap Actions on entry: Send Accept Message Disable Fast Role Swap Receiver if enabled Power = Explicit Contract PD = Connected Accept Message received PE_PRS_SNK_SRC_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PE_PRS_SNK_SRC_ Source_on Actions on entry: Tell Device Policy Manager to turn on Source Power = Transition to source on PD = Connected VBUS is at vSafe5V Actions on exit: Send PS_RDY Message PE_SRC_Startup Message sent PE_PRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Source off PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 899  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.4.2 PE_PRS_SNK_SRC_Evaluate_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK. 8.3.3.19.4.3 PE_PRS_SNK_SRC_Accept_Swap State On entry to the PE_PRS_SNK_SRC_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message and Shall disable the Fast Role Swap receiver if this is enabled. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.4.4 PE_PRS_SNK_SRC_Transition_to_off State On entry to the PE_PRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Assert_Rp state when:  A PS_RDY Message is received. 8.3.3.19.4.5 PE_PRS_SNK_SRC_Assert_Rp State On entry to the PE_PRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.4.6 PE_PRS_SNK_SRC_Source_on State On entry to the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Source Port VBUS is at vSafe5V. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Page 900 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.4.7 PE_PRS_SNK_SRC_Send_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.4.8 PE_PRS_SNK_SRC_Reject_Swap State On entry to the PE_PRS_SNK_SRC_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 901 8.3.3.19.5 Policy Engine in Source to Sink Fast Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.178, "Dual-Role Port in Source to Sink Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Page 902 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.178 Dual-Role Port in Source to Sink Fast Role Swap State Diagram PE_SRC_Ready PE_FRS_SRC_SNK_ Evaluate_Swap Actions on entry: Ask Device Policy Manager if Fast Role Swap signaled on CC wire Power = Implicit Contract PD = Connected PE_FRS_SRC_SNK_ Transition_to_off Actions on entry: Wait for VBUS to reach vSafe5V Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Implicit Contract PD = Connected Fast Role Swap signaled Accept Message sent PS_RDY Message received PE_SNK_Startup PE_FRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Implicit contract PD = Connected VBUS at vSafe5V Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Accept Message not sent after retries (no GoodCRC received) PE_SRC_Hard_Reset FR_Swap Message received Fast Role Swap not signaled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 903 8.3.3.19.5.1 PE_SRC_Ready State The Fast Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Evaluate_Swap state when:  An FR_Swap Message is received. 8.3.3.19.5.2 PE_FRS_SRC_SNK_Evaluate_Swap State On entry to the PE_FRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether Fast Role Swap has been signaled on the CC wire. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Fast Role Swap has been signaled. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Device Policy Manager indicates that a Fast Role Swap is not being signaled. 8.3.3.19.5.3 PE_FRS_SRC_SNK_Accept_Swap State On entry to the PE_FRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Accept Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.5.4 PE_FRS_SRC_SNK_Transition_to_off State On entry to the PE_FRS_SRC_SNK_Transition_to_off state the Policy Engine Shall wait until VBUS has discharged to vSafe5V. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that VBUS has discharged to vSafe5V. 8.3.3.19.5.5 PE_FRS_SRC_SNK_Assert_Rd State On entry to the PE_FRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.5.6 PE_FRS_SRC_SNK_Wait_Source_on State On entry to the PE_FRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the New Source is now applying Rp. The Policy Engine Shall transition to the ErrorRecovery state when: Page 904 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 905 8.3.3.19.6 Policy Engine in Sink to Source Fast Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.179, "Dual-role Port in Sink to Source Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 906 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.179 Dual-role Port in Sink to Source Fast Role Swap State Diagram PE_FRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Power = Implicit Contract PD = Connected Fast Swap signal detected on CC Wire PE_FRS_SNK_SRC_ Send_Swap Actions on entry: Send FR_Swap Message Initialize and run SenderResponseTimer Power = Implicit Contract PD = Connected Accept Message received PE_FRS_SNK_SRC_ Source_on Actions on entry: Send PS_RDY Message Power = Transition to source on PD = Connected PS_RDY Message sent PE_SRC_Startup PE_FRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Implicit Contract PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout SenderResponseTimer timeout | FR_Swap Message not sent after retries (no GoodCRC received) PE_FRS_SNK_SRC_Vbus_Applied Actions on entry: Request Device Policy Manager to notify when vSafe5v is being applied by the local power source. Power = Implicit Contract PD = Connected New Source is applying vSafe5V PE_FRS_SNK_SRC_ Start_AMS Actions on entry: Notify the Protocol Layer that the first Message in the AMS will follow. Power = Implicit Contract PD = Connected Protocol Layer notified Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 907 8.3.3.19.6.1 PE_FRS_SNK_SRC_Start_AMS State The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Start_AMS state from any other state provided there is an Explicit Contract in place when:  The Sink Capabilities received from the Initial Source by the Policy Engine has at least one of the Fast Role Swap bits set.  The system has sufficient reserve power to provide the requested current to the Initial Source, as requested in the Fast Role Swap bits in the Sink Capabilities, and is willing to dedicate it to the Port  The Device Policy Manager indicates that a Fast Role Swap signal has been detected on the CC wire. On entry to the PE_FRS_SNK_SRC_Start_AMS state the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Send_Swap state when:  The Protocol Layer has been notified. 8.3.3.19.6.2 PE_FRS_SNK_SRC_Send_Swap State On entry to the PE_FRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send an FR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. The Policy Engine Shall transition to the ErrorRecovery state when:  The SenderResponseTimer times out or  The FR_Swap Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. 8.3.3.19.6.3 PE_FRS_SNK_SRC_Transition_to_off State On entry to the PE_FRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_VBUS_Applied state when:  A PS_RDY Message is received. 8.3.3.19.6.4 PE_FRS_SNK_SRC_VBUS_Applied State On entry to the PE_FRS_SNK_SRC_VBUS_Applied state the Policy Engine waits for a notification from the Device Policy Manager that the local power source has applied vSafe5V to VBUS (see Section 5.8.6.3, "Fast Role Swap Detection"). Note: This could have already been applied prior to entering this state or could be applied while waiting in this state. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Assert_Rp state when:  The Device Policy Manager indicates that vSafe5V is being applied. 8.3.3.19.6.5 PE_FRS_SNK_SRC_Assert_Rp State On entry to the PE_FRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. Page 908 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rp is asserted. 8.3.3.19.6.6 PE_FRS_SNK_SRC_Source_on State On entry to the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 909 8.3.3.19.7 Dual-Role (Source Port) Get Source Capabilities State Diagram Figure 8.180, "Dual-Role (Source) Get Source Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.180 Dual-Role (Source) Get Source Capabilities diagram 8.3.3.19.7.1 PE_DR_SRC_Get_Source_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap state, from the PE_SRC_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready State (see Figure 8.132, "Source Port State Diagram") when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. get source capabilities request from Device Policy Manager SPR Souce Capabilities requested & Source_Capabilities Message received | EPR Souce Capabilities requested & EPR_Source_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap Actions on entry: If SPR Source Capabilities requested Send Get_Source_Cap Message1 If EPR Source Capabilities requested Send EPR_Get_Source_Cap Message1 Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source capabilities/outcome to Device Policy Manager 1) Either SPR or EPR Source Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. Page 910 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.8 Dual-Role (Source Port) Give Sink Capabilities State Diagram Figure 8.181, "Dual-Role (Source) Give Sink Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a Get_Sink_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.181 Dual-Role (Source) Give Sink Capabilities diagram 8.3.3.19.8.1 PE_DR_SRC_Give_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap state, from the PE_SRC_Ready state, when a Get_Sink_Cap Message or EPR_Get_Sink_Cap Message is received.  On entry to the PE_DR_SRC_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Sink_Capabilities Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap_Ext Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 911 8.3.3.19.9 Dual-Role (Sink Port) Get Sink Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's Sink Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.182 Dual-Role (Sink) Get Sink Capabilities State Diagram 8.3.3.19.9.1 PE_DR_SNK_Get_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap state, from the PE_SNK_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SNK_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). If Fast Role Swap is supported, request Device Policy Manager prepare or disable 5V source and configure the Fast Role Swap receiver based on the Fast Role Swap required USB Type- C Current bits in the received Sink Capabilities. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager1 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Request Device Policy Manager to configure Fast Role Swap if supported 1) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Sink is currently operating in SPR or EPR Mode. Page 912 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.10 Dual-Role (Sink Port) Give Source Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.183 Dual-Role (Sink) Give Source Capabilities State Diagram 8.3.3.19.10.1 PE_DR_SNK_Give_Source_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap state, from the PE_SNK_Ready state, when a Get_Source_Cap Message is received.  On entry to the PE_DR_SNK_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities.  The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source Capabilities Message has been successfully sent. (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities Message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 913 8.3.3.19.11 Dual-Role (Source Port) Get Source Capabilities Extended State Diagram Figure 8.184, "Dual-Role (Source) Get Source Capabilities Extended State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.184 Dual-Role (Source) Get Source Capabilities Extended State Diagram 8.3.3.19.11.1 PE_DR_SRC_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Page 914 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.12 Dual-Role (Sink Port) Give Source Capabilities Extended State Diagram Figure 8.185, "Dual-Role (Sink) Give Source Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.185 Dual-Role (Sink) Give Source Capabilities Extended diagram 8.3.3.19.12.1 PE_DR_SNK_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_DR_SNK_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 915 8.3.3.19.13 Dual-Role (Sink Port) Get Sink Capabilities Extended State Dia- gram Figure 8.186, "Dual-Role (Sink) Get Sink Capabilities Extended State Diagram" shows the state diagram for a Dual- Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.186 Dual-Role (Sink) Get Sink Capabilities Extended State Diagram 8.3.3.19.13.1 PE_DR_SNK_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Sink_Capabilities_Extended Message is received.  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Sink extended capabilities/outcome to Device Policy Manager Page 916 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.14 Dual-Role (Source Port) Give Sink Capabilities Extended State Diagram Figure 8.187, "Dual-Role (Source) Give Sink Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.187 Dual-Role (Source) Give Sink Capabilities Extended diagram 8.3.3.19.14.1 PE_DR_SRC_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_DR_SRC_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Sink Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram")when:  The Sink_Capabilities_Extended Message has been successfully sent. _Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink Capabilities Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 917 8.3.3.19.15 Dual-Role (Source Port) Get Source Information State Diagram Figure 8.188, "Dual-Role (Source) Get Source Information State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.188 Dual-Role (Source) Get Source Information State Diagram 8.3.3.19.15.1 PE_DR_SRC_Get_Source_Info State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Info state, from the PE_SRC_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Info Message is received.  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Page 918 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.16 Dual-Role (Sink Port) Give Source Information State Diagram Figure 8.189, "Dual-Role (Source) Give Source Information diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.189 Dual-Role (Source) Give Source Information diagram 8.3.3.19.16.1 PE_DR_SNK_Give_Source_Info State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Info state, from the PE_SNK_Ready state, when a Get_Source_Info Message is received. On entry to the PE_DR_SNK_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 919 8.3.3.20 VCONN Swap State Diagram The State Diagram in this section Shall apply to Ports that supply VCONN. Figure 8.190, "VCONN Swap State Diagram" shows the state operation for a Port on sending or receiving a VCONN Swap request. Figure 8.190 VCONN Swap State Diagram 8.3.3.20.1 PE_VCS_Send_Swap State The PE_VCS_Send_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a request from the Device Policy Manager to perform a VCONN Swap. On entry to the PE_VCS_Send_Swap state the Policy Engine Shall send a VCONN_Swap Message and start the SenderResponseTimer. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  An Accept Message is received and  The Port is presently the VCONN Source. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  An Accept Message is received and  The Port is not presently the VCONN Source. PE_VCS_Evaluate_Swap Actions on entry: Get evaluation of VCONN swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_VCS_Turn_On_VCONN Actions on entry: Tell Device Policy Manager to turn on VCONN PE_VCS_Send_PS_Rdy Actions on entry: Send PS_RDY Message PE_VCS_Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected PE_VCS_Reject_VCONN_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent VCONN_Swap Message received VCONN Swap ok (Not Presently VCONN SOURCE & VCONN Swap not ok) | Further evaluation Required Accept Message sent & Not presently VCONN Source1 VCONN turned on PS_RDY Message sent VCONNOnTimer Timeout Hard Reset: Consumer/Provider -> PE_SNK_Hard_Reset Provider/Consumer -> PE_SRC_Hard_Reset Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_VCS_Wait_for_VCONN Actions on entry: Start VCONNOnTimer Power = Explicit Contract PD = Connected Accept Message sent & Presently VCONN Source1 PE_VCS_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = Connected PS_RDY Message received Device Policy Manager Informed VCONN Swap required (indication from Device Policy Manager) PE_VCS_Send_Swap Actions on entry: Send VCONN_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout Accept Message received & Presently VCONN Source1 Accept Message received & Not presently VCONN Source1 PE_VCS_Force_VCONN2 Actions on entry: Tell Device Policy Manager to turn on VCONN Power = Explicit Contract PD = Connected Not_Supported Message received & Not presently VCONN Source1 VCONN turned on PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Entry_ACK PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_SNK_EPR_Mode_Entry_Wait_For_Response PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable 1) A Port is presently the VCONN Source if it has the responsibility for supplying VCONN even if VCONN has been turned off. 2) The PE_VCS_Force_VCONN state is Optional. Page 920 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  A Reject Message is received or  A Wait Message is received or  The SenderResponseTimer times out. The Policy Engine May transition to the PE_VCS_Force_VCONN state when:  A Not_Supported Message is received and  The Port is not presently the VCONN Source. 8.3.3.20.2 PE_VCS_Evaluate_Swap State The PE_VCS_Evaluate_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a VCONN_Swap Message. On entry to the PE_VCS_Evaluate_Swap state the Policy Engine Shall request the Device Policy Manager for an evaluation of the VCONN Swap request. The Policy Engine Shall transition to the PE_VCS_Accept_Swap state when:  The Device Policy Manager indicates that a VCONN Swap is OK. The Policy Engine Shall transition to the PE_VCS_Reject_Swap state when:  The Port is not presently the VCONN Source and the Device Policy Manager indicates that a VCONN Swap is not OK or  The Device Policy Manager indicates that a VCONN Swap cannot be done at this time. 8.3.3.20.3 PE_VCS_Accept_Swap State On entry to the PE_VCS_Accept_Swap state the Policy Engine Shall send an Accept Message. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is on. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is off. 8.3.3.20.4 PE_VCS_Reject_Swap State On entry to the PE_VCS_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a VCONN Swap at this time.  A Wait Message if further evaluation of the VCONN Swap request is required. Note: In this case it is expected that the Port will send a VCONN_Swap Message at a later time. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 921 8.3.3.20.5 PE_VCS_Wait_for_VCONN State On entry to the PE_VCS_Wait_For_VCONN state the Policy Engine Shall start the VCONNOnTimer. The Policy Engine Shall transition to the PE_VCS_Turn_Off_VCONN state when:  A PS_RDY Message is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state when:  The VCONNOnTimer times out. 8.3.3.20.6 PE_VCS_Turn_Off_VCONN State On entry to the PE_VCS_Turn_Off_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Device Policy Manager has been informed. 8.3.3.20.7 PE_VCS_Turn_On_VCONN State On entry to the PE_VCS_Turn_On_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition to the PE_VCS_Send_Ps_Rdy state when:  The Port's VCONN is on. 8.3.3.20.8 PE_VCS_Send_PS_Rdy State On entry to the PE_VCS_Send_Ps_Rdy state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The PS_RDY Message has been sent. 8.3.3.20.9 PE_VCS_Force_VCONN State On entry to the PE_VCS_Force_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Port's VCONN is on. 8.3.3.21 Initiator Structured VDM State Diagrams The State Diagrams in this section Shall apply to all Initiators. Page 922 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.1 Initiator Structured VDM Discover Identity State Diagram Figure 8.191, "Initiator to Port VDM Discover Identity State Diagram" shows the state diagram for an Initiator when discovering the identity of its Port Partner or Cable Plug. Figure 8.191 Initiator to Port VDM Discover Identity State Diagram 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_Request State The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the identity of the Port Partner or Cable Plug or  The DiscoverIdentityTimer times out. The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from the PE_SRC_EPR_Mode_Discover_Cable state when:  The Cable Plug Discovery Process has been initiated. PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_INIT_PORT_VDM_Identity_Request Actions on entry: Send Discover Identity request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests identity discovery1 | DiscoverIdentityTimer timeout Discover Identity ACK received PE_INIT_PORT_VDM_Identity_ACKed Actions on entry: Inform DPM of identity Power = Explicit Contract PD = Connected PE_INIT_PORT_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR 1) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 923 On entry to the PE_INIT_PORT_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out. 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_ACKed State On entry to the PE_INIT_PORT_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. 8.3.3.21.1.3 PE_INIT_PORT_VDM_Identity_NAKed State On entry to the PE_INIT_PORT_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. Page 924 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.2 Initiator Structured VDM Discover SVIDs State Diagram Figure 8.192, "Initiator VDM Discover SVIDs State Diagram" shows the state diagram for an Initiator when discovering SVIDs of its Port Partner or Cable Plug. Figure 8.192 Initiator VDM Discover SVIDs State Diagram 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_Request State The Policy Engine transitions to the PE_INIT_VDM_SVIDs_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the SVIDs of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_SVIDs_Request state the Policy Engine Shall send a Structured VDM Discover SVIDs Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_ACKed state when:  A Structured VDM Discover SVIDs ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_NAKed state when:  A Structured VDM Discover SVIDs NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_SVIDs_Request Actions on entry: Send Discover SVIDs request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests SVIDs discovery Discover SVIDs ACK received PE_INIT_VDM_SVIDs_ACKed Actions on entry: Inform DPM of SVIDs Power = Explicit Contract PD = Connected PE_INIT_VDM_SVIDs_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover SVIDs NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 925 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_ACKed State On entry to the PE_INIT_VDM_SVIDs_ACKed state the Policy Engine Shall inform the Device Policy Manager of the SVIDs information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. 8.3.3.21.2.3 PE_INIT_VDM_SVIDs_NAKed State On entry to the PE_INIT_VDM_SVIDs_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. Page 926 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.3 Initiator Structured VDM Discover Modes State Diagram Figure 8.193, "Initiator VDM Discover Modes State Diagram" shows the state diagram for an Initiator when discovering Modes of its Port Partner or Cable Plug. Figure 8.193 Initiator VDM Discover Modes State Diagram 8.3.3.21.3.1 PE_INIT_VDM_Modes_Request State The Policy Engine transitions to the PE_INIT_VDM_Modes_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the Modes of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_Modes_Request state the Policy Engine Shall send a Structured VDM Discover Modes Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_ACKed state when:  A Structured VDM Discover Modes ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_NAKed state when:  A Structured VDM Discover Modes NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Modes_Request Actions on entry: Send Discover Modes request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests Modes discovery Discover Modes ACK received PE_INIT_VDM_Modes_ACKed Actions on entry: Inform DPM of Modes Power = Explicit Contract PD = Connected PE_INIT_VDM_Modes_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Modes NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 927 8.3.3.21.3.2 PE_INIT_VDM_Modes_ACKed State On entry to the PE_INIT_VDM_Modes_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Modes information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. 8.3.3.21.3.3 PE_INIT_VDM_Modes_NAKed State On entry to the PE_INIT_VDM_Modes_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Page 928 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.4 Initiator Structured VDM Attention State Diagram Figure 8.194, "Initiator VDM Attention State Diagram" shows the state diagram for an Initiator when sending an Attention Command request. Figure 8.194 Initiator VDM Attention State Diagram 8.3.3.21.4.1 PE_INIT_VDM_Attention_Request State The Policy Engine transitions to the PE_INIT_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  When the Device Policy Manager requests attention from its Port Partner. On entry to the PE_INIT_VDM_Attention_Request state the Policy Engine Shall send an Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Attention Command request has been sent. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Attention_Request Actions on entry: Send Attention Command request Power = Explicit Contract PD = Connected Attention request from DPM Attention Command request sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 929 8.3.3.22 Responder Structured VDM State Diagrams 8.3.3.22.1 Responder Structured VDM Discover Identity State Diagram Figure 8.195, "Responder Structured VDM Discover Identity State Diagram" shows the state diagram for a Responder receiving a Discover Identity Command request. Figure 8.195 Responder Structured VDM Discover Identity State Diagram 8.3.3.22.1.1 PE_RESP_VDM_Get_Identity State The Policy Engine transitions to the PE_RESP_VDM_Get_Identity state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Identity Command request is received. On entry to the PE_RESP_VDM_Get_Identity state the Responder Shall request identity information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Identity state when:  Identity information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Identity_NAK state when:  The Device Policy Manager indicates that the response to the Discover Identity Command request is NAK or BUSY. 8.3.3.22.1.2 PE_RESP_VDM_Send_Identity State On entry to the PE_RESP_VDM_Send_Identity state the Responder Shall send the Structured VDM Discover Identity ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Discover Identity ACK Command response has been sent. 8.3.3.22.1.3 PE_RESP_VDM_Get_Identity_NAK State On entry to the PE_RESP_VDM_Get_Identity_NAK state the Policy Engine Shall send a Structured VDM Discover Identity NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Identity NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Identity Actions on entry: Send Discover Identity ACK Power = Explicit Contract PD = Connected Discover Identity request Discover Identity ACK sent PE_RESP_VDM_Get_Identity Actions on entry: Request Identity information from DPM Power = Explicit Contract PD = Connected Identity information from DPM PE_RESP_VDM_Get_Identity_NAK Actions on entry: Send Discover Identity NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Identity NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 930 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.2 Responder Structured VDM Discover SVIDs State Diagram Figure 8.196, "Responder Structured VDM Discover SVIDs State Diagram" shows the state diagram for a Responder when receiving a Discover SVIDs Command. Figure 8.196 Responder Structured VDM Discover SVIDs State Diagram 8.3.3.22.2.1 PE_RESP_VDM_Get_SVIDs State The Policy Engine transitions to the PE_RESP_VDM_Get_SVIDs state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover SVIDs Command request is received. On entry to the PE_RESP_VDM_Get_SVIDs state the Responder Shall request SVIDs information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_SVIDs state when:  SVIDs information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_SVIDs_NAK state when:  The Device Policy Manager indicates that the response to the Discover SVIDs Command request is NAK or BUSY. 8.3.3.22.2.2 PE_UFP_VDM_Send_SVIDs State On entry to the PE_RESP_VDM_Send_SVIDs state the Responder Shall send the Structured VDM Discover SVIDs ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs ACK Command response has been sent. 8.3.3.22.2.3 PE_UFP_VDM_Get_SVIDs_NAK State On entry to the PE_RESP_VDM_Get_SVIDs_NAK state the Policy Engine Shall send a Structured VDM Discover SVIDs NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_SVIDs Actions on entry: Send Discover SVIDs ACK Power = Explicit Contract PD = Connected Discover SVIDs request Discover SVIDs ACK sent PE_RESP_VDM_Get_SVIDs Actions on entry: Request SVIDs information from DPM Power = Explicit Contract PD = Connected SVIDs information from DPM PE_RESP_VDM_Get_SVIDs_NAK Actions on entry: Send Discover SVIDs NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover SVIDs NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 931 8.3.3.22.3 Responder Structured VDM Discover Modes State Diagram Figure 8.197, "Responder Structured VDM Discover Modes State Diagram" shows the state diagram for a Responder on receiving a Discover Modes Command. Figure 8.197 Responder Structured VDM Discover Modes State Diagram 8.3.3.22.3.1 PE_RESP_VDM_Get_Modes State The Policy Engine transitions to the PE_RESP_VDM_Get_Modes state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Modes Command request is received. On entry to the PE_RESP_VDM_Get_Modes state the Responder Shall request Modes information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Modes state when:  Modes information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Modes_NAK state when:  The Device Policy Manager indicates that the response to the Discover Modes Command request is NAK or BUSY. 8.3.3.22.3.2 PE_RESP_VDM_Send_Modes State On entry to the PE_RESP_VDM_Send_Modes state the Responder Shall send the Structured VDM Discover Modes ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes ACK Command response has been sent. 8.3.3.22.3.3 PE_RESP_VDM_Get_Modes_NAK State On entry to the PE_RESP_VDM_Get_Modes_NAK state the Policy Engine Shall send a Structured VDM Discover Modes NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Modes Actions on entry: Send Discover Modes ACK Power = Explicit Contract PD = Connected Discover Modes request Discover Modes ACK sent PE_RESP_VDM_Get_Modes Actions on entry: Request Modes information from DPM Power = Explicit Contract PD = Connected Modes information from DPM PE_RESP_VDM_Get_Modes_ NAK Actions on entry: Send Discover Modes NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Modes NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 932 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.4 Receiving a Structured VDM Attention State Diagram Figure 8.198, "Receiving a Structured VDM Attention State Diagram" shows the state diagram when receiving an Attention Command request. Figure 8.198 Receiving a Structured VDM Attention State Diagram 8.3.3.22.4.1 PE_RCV_VDM_Attention_Request State The Policy Engine transitions to the PE_RCV_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  An Attention Command request is received. On entry to the PE_RCV_VDM_Attention_Request state the Policy Engine Shall inform the Device Policy Manager of the Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. PE_SRC_Ready or PE_SNK_Ready PE_RCV_VDM_Attention_Request Actions on entry: Inform Device Policy Manager of Attention Command request Power = Explicit Contract PD = Connected Attention Command request received DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 933 8.3.3.23 DFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all DFPs that support Structured VDMs. 8.3.3.23.1 DFP Structured VDM Mode Entry State Diagram Figure 8.199, "DFP VDM Mode Entry State Diagram" shows the state operation for a DFP when entering a Mode. Figure 8.199 DFP VDM Mode Entry State Diagram 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Entry_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug enter a Mode. On entry to the PE_DFP_VDM_Mode_Entry_Request state the Policy Engine Shall send a Structured VDM Enter Mode Command request and Shall start the VDMModeEntryTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Enter Mode ACK Command response is received. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_NAKed state when:  A Structured VDM Enter Mode NAK or BUSY Command response is received or  The VDMModeEntryTimer times out. PE_SRC_Ready or PE_SNK_Ready (DFP) DPM requests Mode entry1 PE_DFP_VDM_Mode_Entry_ACKed Actions on entry: Request DPM to enter the mode Power = Explicit Contract PD = Connected PE_DFP_VDM_Mode_Entry_Request Actions on entry: Send Mode Entry request Start VDMModeEntryTimer Power = Explicit Contract PD = Connected Mode Entry ACK received Mode entered PE_DFP_VDM_Mode_Entry_NAKed Actions on entry: Inform DPM of reason for failure Power = Explicit Contract PD = Connected Mode Entry NAK/BUSY Received | VDMModeEntryTimer timeout | Protocol Error3 DPM informed2 1) The Device Policy Manager Shall have placed the system into USB Safe State before issuing this request when entering Modal operation. 2) The Device Policy Manager Shall have returned the system to USB operation if not in Modal operation at this point. 3) Protocol Errors are handled by informing the DPM, returning to USB Safe State and then processing the Message once the PE_SRC_Ready or PE_SNK_Ready state has been entered. Page 934 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_ACKed State On entry to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall request the Device Policy Manager to enter the Mode. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Mode has been entered. 8.3.3.23.1.3 PE_DFP_VDM_Mode_Entry_NAKed State On entry to the PE_DFP_VDM_Mode_Entry_NAKed state the Policy Engine Shall inform the Device Policy Manager of the reason for failure (NAK, BUSY, timeout or Protocol Error). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 935 8.3.3.23.2 DFP Structured VDM Mode Exit State Diagram Figure 8.200, "DFP VDM Mode Exit State Diagram" shows the state diagram for a DFP when exiting a Mode. Figure 8.200 DFP VDM Mode Exit State Diagram 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Exit_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug exit a Mode. On entry to the PE_DFP_VDM_Mode_Exit_Request state the Policy Engine Shall send a Structured VDM Exit Mode Command request and Shall start the VDMModeExitTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Exit Mode ACK or NAK Command response is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state depending on the present Power Role when:  A Structured VDM Exit Mode BUSY Command response is received or  The VDMModeExitTimer times out. 8.3.3.23.2.2 PE_DFP_VDM_DFP_Mode_Exit_ACKed State On Exit to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall inform the Device Policy Manager Of the result: ACK or NAK. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when: PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DFP_VDM_Mode_Exit_Request Actions on entry: Send Exit Mode request Start VDMModeExitTimer Power = Explicit Contract PD = Connected DPM indicates Mode exit PE_DFP_VDM_Exit_Mode_ACKed Actions on entry: Inform DPM of ACK or NAK Power = Explicit Contract PD = Connected Exit Mode ACK/NAK received DPM informed1 PE_SRC_Hard_Reset or PE_SNK_Hard_Reset (DFP) Exit Mode BUSY Received | VDMModeExitTimer Timeout 1) The Device Policy Manager is required to return the system to USB operation at this point when exiting Modal Operation. Page 936 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 937 8.3.3.24 UFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all UFPs that support Structured VDMs. 8.3.3.24.1 UFP Structured VDM Enter Mode State Diagram Figure 8.201, "UFP Structured VDM Enter Mode State Diagram" shows the state diagram for a UFP in response to an Enter Mode Command. Figure 8.201 UFP Structured VDM Enter Mode State Diagram 8.3.3.24.1.1 PE_UFP_VDM_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_UFP_VDM_Evaluate_Mode_Entry state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_UFP_VDM_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected Enter Modes request1 PE_UFP_VDM_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_UFP_VDM_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_UFP_VDM_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 938 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_ACK State On entry to the PE_UFP_VDM_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.24.1.3 PE_UFP_VDM_Mode_Entry_NAK State On entry to the PE_UFP_VDM_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 939 8.3.3.24.2 UFP Structured VDM Exit Mode State Diagram Figure 8.202, "UFP Structured VDM Exit Mode State Diagram" shows the state diagram for a UFP in response to an Exit Mode Command. Figure 8.202 UFP Structured VDM Exit Mode State Diagram 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit State The Policy Engine transitions to the PE_UFP_VDM_Mode_Exit state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_UFP_VDM_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. PE_UFP_VDM_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Power = Explicit Contract PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_UFP_VDM_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Power = Explicit Contract PD = Connected Mode exited PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected PE_UFP_VDM_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Power = Explicit Contract PD = Connected DPM says NAK Exit Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 940 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_ACK State On entry to the PE_UFP_VDM_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.24.2.3 PE_UFP_VDM_Mode_Exit_NAK State On entry to the PE_UFP_VDM_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 941 8.3.3.25 Cable Plug Specific State Diagrams The State Diagrams in this section Shall apply to all Cable Plugs that support Structured VDMs. 8.3.3.25.1 Cable Plug Cable Ready State Diagram Figure 8.203, "Cable Ready State Diagram" shows the Cable Ready state diagram for a Cable Plug. Figure 8.203 Cable Ready State Diagram 8.3.3.25.1.1 PE_CBL_Ready State The PE_CBL_Ready state shown in the following sections is the normal operational state for a Cable Plug and where it starts after power up or a Hard/Cable Reset. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Power up | Hard Reset Complete | Cable Reset Complete Page 942 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2 Soft/Hard/Cable Reset 8.3.3.25.2.1 Cable Plug Soft Reset State Diagram Figure 8.204, "Cable Plug Soft Reset State Diagram" shows the Cable Plug state diagram on reception of a Soft_Reset Message. Figure 8.204 Cable Plug Soft Reset State Diagram 8.3.3.25.2.1.1 PE_CBL_Soft_Reset State The PE_CBL_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received from the Protocol Layer. On entry to the PE_CBL_Soft_Reset state the Policy Engine Shall reset the Protocol Layer in the Cable Plug and Shall then request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Accept Message has been sent or  The Protocol Layer indicates that a transmission error has occurred. Accept Message sent | Transmission Error indication from Protocol Layer Soft Reset Message received PE_CBL_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept Message Cable = Awake PD = Connected PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 943 8.3.3.25.2.2 Cable Plug Hard Reset State Diagram Figure 8.205, "Cable Plug Hard Reset State Diagram" shows the Cable Plug state diagram for a Hard Reset or Cable Reset. Figure 8.205 Cable Plug Hard Reset State Diagram 8.3.3.25.2.2.1 PE_CBL_Hard_Reset State The PE_CBL_Hard_Reset state Shall be entered from any state when either Hard Reset Signaling or Cable Reset Signaling is detected. On entry to the PE_CBL_Hard_Reset state the Policy Engine Shall reset the Cable Plug (equivalent to a power cycle). The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Cable Plug reset is complete. Hard Reset signalling Received | Cable Reset Command PE_CBL_Hard_Reset Actions on entry: Reset Cable Plug Cable = Awake/Asleep PD = Not Connected Cable reset complete PE_CBL_Ready Page 944 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.3 DFP/VCONN Source SOP'/SOP'' Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram Figure 8.206, "DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the Policy Engine in a VCONN Source when performing a Soft Reset or Cable Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.206 DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Soft_Reset State The PE_DFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_DFP_VCS_CBL_Send_Soft_Reset state the DFP Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug/VPD, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the DFP VCONN Source's Power Role, when:  There is no Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Send_Capabilities state or PE_SRC_Discovery state, depending on the DFP's VCONN Source's Power Role, when:  There is an Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to the PE_DFP_VCS_CBL_Send_Cable_Reset state when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_DFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered| Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error In Explicit Contract & Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_DFP_VCS_CBL_Send_Cable_Reset Actions on entry: Send Cable Reset Message Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Cable Reset Request from Device Policy Manager Cable Reset sent PE_SRC_Send_Capabilities or PE_SRC_Discovery2 (VCONN Source) Not in Explicit Contract & Accept Message Received on SOP’/SOP’’ 1) Excludes the Soft_Reset Message itself. 2) Sink only communicates with the Cable Plug when in an Explicit Contract. If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 945 8.3.3.25.2.3.2 PE_DFP_VCS_CBL_Send_Cable_Reset State The PE_DFP_VCS_CBL_Send_Cable_Reset state Shall be entered from any state when the Device Policy Manager requests a Cable Reset. On entry to the PE_DFP_VCS_CBL_Send_Cable_Reset state the DFP Policy Engine Shall request the Protocol Layer to send Cable Reset Signaling. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the VCONN Source's Power Role, when:  Cable Reset Signaling has been sent. Page 946 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.4 UFP/VCONN Source SOP'/SOP'' Soft Reset of a Cable Plug or VPD State Diagram Figure 8.207, "UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the UFP Policy Engine in a VCONN Source when performing a Soft Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.207 UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.4.1 PE_UFP_VCS_CBL_Send_Soft_Reset State The PE_UFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_UFP_VCS_CBL_Send_Soft_Reset state the Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the UFP VCONN Source's Power Role, when:  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state, depending on the UFP VCONN Source's Power Role, when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_UFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered | Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_SRC_Hard_Reset or PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 947 8.3.3.25.3 Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" shows the state diagram for Source discovery of identity information from a Cable Plug during the startup sequence. Figure 8.208 Source Startup Structured VDM Discover Identity State Diagram 8.3.3.25.3.1 PE_SRC_VDM_Identity_Request State The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Startup state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Discovery state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug and  The DiscoverIdentityCounter < nDiscoverIdentityCount. Even though there has been a transition out of the PE_SRC_Discovery state the SourceCapabilityTimer Shall continue to run during the states shown in Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" and Shall Not be initialized on re-entry to PE_SRC_Discovery. PE_SRC_Send_Capabilities or PE_SRC_Discovery1 PE_SRC_VDM_Identity_Request Actions on entry: Send Discover Identity request Increment the DiscoverIdentityCounter Start VDMResponseTimer Power = No or Implicit Contract Cable Plug = Not PD Connected DPM requests identity discovery3 & Protocol Layer Reset Complete Discover Identity ACK received PE_SRC_VDM_Identity_ACKed Actions on entry: Inform DPM of identity PE_SRC_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power =No or Implicit Contract Cable Plug = PD Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout | Discover Identity request sending failure (without GoodCRC) DPM informed DPM informed PE_SRC_Startup DPM requests identity discovery & DiscoverIdentityCounter < nDiscoverIdentityCount2 PE_SRC_Discovery Power = No or Implicit Contract Cable Plug = PD Connected 1) If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. 2) The SourceCapabilityTimer continues to run during the states defined in this diagram even though there has been an exit from the PE_SRC_Discovery state. This ensures that Source_Capabilities Messages are sent out at a regular rate. 3) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Page 948 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: An EPR Source is required to discover the identity of the Cable Plug prior to entering the First Explicit Contract (see Section 6.4.10.1, "Process to enter EPR Mode") On entry to the PE_SRC_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request, Shall increment the DiscoverIdentityCounter and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out or  The Structured VDM Discover Identity Command request Message sending fails (no GoodCRC Message received after retries). 8.3.3.25.3.2 PE_SRC_VDM_Identity_ACKed State On entry to the PE_SRC_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. 8.3.3.25.3.3 PE_SRC_VDM_Identity_NAKed State On entry to the PE_SRC_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 949 8.3.3.25.4 Cable Plug Mode Entry/Exit 8.3.3.25.4.1 Cable Plug Structured VDM Enter Mode State Diagram Figure 8.209, "Cable Plug Structured VDM Enter Mode State Diagram" shows the state diagram for a Cable Plug in response to an Enter Mode Command. Figure 8.209 Cable Plug Structured VDM Enter Mode State Diagram 8.3.3.25.4.1.1 PE_CBL_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_CBL_Evaluate_Mode_Entry state from the PE_CBL_Ready state when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_CBL_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_ACK State On entry to the PE_CBL_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Enter Modes request1 PE_CBL_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_CBL_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_CBL_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 950 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.25.4.1.3 PE_CBL_Mode_Entry_NAK State On entry to the PE_CBL_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 951 8.3.3.25.4.2 Cable Plug Structured VDM Exit Mode State Diagram Figure 8.210, "Cable Plug Structured VDM Exit Mode State Diagram" shows the state diagram for a Cable Plug in response to an Exit Mode Command. Figure 8.210 Cable Plug Structured VDM Exit Mode State Diagram 8.3.3.25.4.2.1 PE_CBL_Mode_Exit State The Policy Engine transitions to the PE_CBL_Mode_Exit state from the PE_CBL_Ready state when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_CBL_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_ACK State On entry to the PE_CBL_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. PE_CBL_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Cable = Awake PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_CBL_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Cable = Awake PD = Connected Mode exited PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected PE_CBL_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Cable = Awake PD = Connected DPM says NAK Exit Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 952 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.25.4.2.3 PE_CBL_Mode_Exit_NAK State On entry to the PE_CBL_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 953 8.3.3.26 EPR Mode State Diagrams 8.3.3.26.1 Source EPR Mode Entry State Diagram Figure 8.211, "Source EPR Mode Entry State Diagram" shows the state diagram for an EPR Source in response to an EPR_Mode Message. Figure 8.211 Source EPR Mode Entry State Diagram 8.3.3.26.1.1 PE_SRC_Evaluate_EPR_Mode_Entry State The Policy Engine transitions to the PE_SRC_Evaluate_EPR_Mode_Entry state from the PE_SRC_Ready state when:  An EPR_Mode (Enter) Message is received from the Sink. On Entry to the PE_SRC_Evaluate_EPR_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the EPR_Mode (Enter) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Ack state when:  The Device Policy Manager indicates that EPR Mode can be entered. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Device Policy Manager indicates that the EPR Mode is not to be entered. EPR_Mode (Enter) received PE_SRC_EPR_Mode_Entry_ACK Actions on entry: Send EPR Enter Mode Acknowledge If Source is not the VCONN Source initiate VCONN Swap process PE_SRC_Evaluate_EPR Mode_Entry Actions on entry: Request DPM to evaluate request to enter EPR Mode Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Failed Actions on entry: Send Enter Mode (Enter Failed) with appropriate failure code. DPM says enter EPR Mode EPR Enter Mode (Enter Failed) sent PE_SRC_Ready PE_VCS_Send_Swap PE_VCS_Force_VCONN or PE_VCS_Send_PS_RDY VCONN Swap Process DPM says don’t enter EPR Mode PE_SRC_EPR_Mode_Discover_Cable Actions on entry: Check Vconn Swap Result if Vconn Swap Process carried out. Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected EPR Enter Mode (Enter Acknowledged) Sent & Source is VCONN Source & Unknown Cable PE_INIT_PORT_VDM_Identity_Request PE_INIT_PORT_VDM_Identity_ACKed or PE_INIT_PORT_VDM_Identity_NAKed Source is the VCONN Source Cable Discovery Process PE_SRC_EPR_Mode_Evaluate_Cable_EPR Actions on entry: Ask DPM to evaluate Cable Discovery results Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Succeeded Actions on entry: Send EPR Mode (Enter Succeeded) Enter EPR Mode. Power = Explicit Contract PD = Connected VCONN Swap Process Complete Cable Discovery Process Complete Cable Plug is EPR capable PE_SRC_Send_Capabilities EPR Mode Entered Cable Plug is not EPR capable EPR Enter Mode (Enter Acknowledged) Sent & (captive cable | known EPR Capable Cable) EPR Enter Mode (Enter Acknowledged) Sent & Source is not VCONN Source & Unknown Cable Page 954 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.1.2 PE_SRC_EPR_Mode_Entry_Ack State On entry to the PE_SRC_EPR_Mode_Entry_Ack state the Policy Engine Shall send a EPR_Mode (Enter Acknowledged) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is a captive cable or a known EPR Cable. The Policy Engine Shall transition to the PE_VCS_Send_Swap state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is unknown. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Discover_Cable state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is the VCONN Source and  The cable is unknown. 8.3.3.26.1.3 PE_SRC_EPR_Mode_Discover_Cable State The Policy Engine transitions to the PE_SRC_EPR_Mode_Discover_Cable state from the PE_VCS_Force_VCONN state or PE_VCS_Send_Ps_Rdy state when:  A Source initiated VCONN Swap process has completed. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_Request state in order to perform Cable Plug discovery when:  The Source is the VCONN Source. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The VCONN Swap process failed (the Source is not the VCONN Source). 8.3.3.26.1.4 PE_SRC_EPR_Mode_Evaluate_Cable_EPR State In the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state the Policy Engine requests the DPM to evaluate the Cable Discovery results. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Succeeded state when:  The Cable Plug is capable of EPR Mode. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Cable Plug is not capable of EPR Mode. 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Succeeded State On entry to the PE_SRC_EPR_Mode_Entry_Succeeded state the Policy Engine Shall send a EPR_Mode (Enter Succeeded) Message and enter EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  EPR Mode has been entered. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 955 8.3.3.26.1.6 PE_SRC_EPR_Mode_Entry_Failed State On entry to the PE_SRC_EPR_Mode_Entry_Failed state the Policy Engine Shall send a EPR_Mode (Enter Failed) Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_Mode (Enter Failed) Message has been sent. Page 956 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.2 Sink EPR Mode Entry State Diagram Figure 8.212, "Sink EPR Mode Entry State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode Entry process. Figure 8.212 Sink EPR Mode Entry State Diagram 8.3.3.26.2.1 PE_SNK_Send_EPR_Mode_Entry State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Entry state from the PE_SNK_Ready state when:  The DPM requests entry into EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Entry state the Policy Engine Shall send an EPR_Mode (Enter) Message and starts the SenderResponseTimer and the SinkEPREnterTimer. Note: The SinkEPREnterTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SNK_EPR_Mode_Wait_For_Response state when:  An EPR_Mode (Enter Acknowledge) Message is received. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or DPM Request EPR Mode Entry PE_SNK_EPR_Mode_Entry_Wait_For_Response Actions on entry: Wait for EPR Enter Mode response PE_SNK_Send_EPR Mode_Entry Actions on entry: Send EPR Mode Entry Message Start SenderResponse Timer Start SinkEPREnterTimer Power = Explicit Contract PD = Connected EPR Enter Mode Acknowledge received PE_SNK_Ready EPR Enter Mode Succeeded received Power = Explicit Contract PD = Connected PE_SNK_Send_Soft_Reset EPR Enter Mode received (!Succceded) | SenderResponseTimer timeout | SinkEPREnterTimer timeout EPR Enter Mode received (!Succceded) | SinkEPREnterTimer timeout Actions on exit: Stop the SinkEPRTimer Enter EPR Mode PE_SNK_Wait_For_Capabilities PE_VCS_Evaluate_Swap VCONN Swap Process VCONN_Swap Message Received VCONN Swap Process completed PE_VCS_Turn_Off_VCONN Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 957  The SenderResponseTimer times out or  The SinkEPREnterTimer times out. 8.3.3.26.2.2 PE_SNK_EPR_Mode_Wait_For_Response State In the State the Policy Engine waits for a confirmation that the EPR Mode entry request has succeeded. On exit from the PE_SNK_EPR_Mode_Wait_For_Response state the Policy Engine Shall stop the SinkEPREnterTimer and enter EPR Mode. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or  The SinkEPREnterTimer times out. The Policy Engine Shall transition to the PE_VCS_Evaluate_Swap State when:  A VCONN_Swap Message is received. The Policy Engine Shall transition back from the PE_VCS_Turn_Off_VCONN State to the PE_SNK_EPR_Mode_Wait_For_Response State when:  The VCONN Swap process has completed. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An EPR_Mode (Enter Succeeded) Message has been received. Page 958 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.3 Source EPR Mode Exit State Diagram Figure 8.213, "Source EPR Mode Exit State Diagram" shows the state diagram for an EPR Source initiating the EPR Mode exit process. Figure 8.213 Source EPR Mode Exit State Diagram 8.3.3.26.3.1 PE_SRC_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SRC_Send_EPR_Mode_Exit state from the PE_SRC_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.3.2 PE_SRC_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SRC_EPR_Mode_Exit_Received state from the PE_SRC_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SRC_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SRC_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SRC_Ready Actions on exit: Exit EPR Mode PE_SRC_Send_Capabilities PE_SRC_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explict Contract with SPR PDO & EPR Mode Exited PE_SRC_Hard_Reset Not in an Explicit Contract with an SPR PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 959 8.3.3.26.4 Sink EPR Mode Exit State Diagram Figure 8.214, "Sink EPR Mode Exit State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode exit process. Figure 8.214 Sink EPR Mode Exit State Diagram 8.3.3.26.4.1 PE_SNK_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Exit state from the PE_SNK_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.4.2 PE_SNK_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SNK_EPR_Mode_Exit_Received state from the PE_SNK_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SNK_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SNK_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SNK_Ready Actions on exit: Exit EPR Mode PE_SNK_Wait_for_Capabilities PE_SNK_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explicit Contract with SPR PDO & EPR Mode Exited PE_SNK_Hard_Reset Not in an Explicit Contract with an SPR PDO Page 960 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27 BIST State diagrams 8.3.3.27.1 BIST Carrier Mode State Diagram Figure 8.215, "BIST Carrier Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Carrier Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.215 BIST Carrier Mode State Diagram 8.3.3.27.1.1 PE_BIST_Carrier_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Carrier_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Carrier Mode BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Carrier_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Carrier Mode (see Section 6.4.3.1, "BIST Carrier Mode") and Shall initialize and run the BISTContModeTimer. BIST message received with Data Object BIST Carrier Mode & VBUS = vSafe5V BISTContModeTimer timeout PE_BIST_Carrier_Mode Actions on entry: Tell Protocol Layer to go to BIST Carrier Mode Initialize and run BISTContModeTimer PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 961 The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  The BISTContModeTimer times out. Page 962 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.2 BIST Test Data Mode State Diagram Figure 8.216, "BIST Test Data Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Test Data Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.216 BIST Test Data Mode State Diagram 8.3.3.27.2.1 PE_BIST_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Test Data BIST Data Object and  VBUS is at vSafe5V. BIST message received with Data Object BIST Test Mode & VBUS = vSafe5V Hard Reset PE_BIST_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Test Mode PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 963 On entry to the PE_BIST_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go into BIST Test Data Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A Hard Reset occurs. Page 964 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.3 BIST Shared Capacity Test Mode State Diagram Figure 8.217, "BIST Shared Capacity Test Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Shared Capacity Test Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.217 BIST Shared Capacity Test Mode State Diagram 8.3.3.27.3.1 PE_BIST_Shared_Capacity_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Shared_Capacity_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Shared Test Mode Entry BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Shared_Capacity_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Shared Capacity Test Mode (see Section 6.4.3.3, "BIST Shared Capacity Test Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A BIST Message is received with a BIST Shared Test Mode Exit BIST Data Object. BIST message received with Data Object BIST Shared Test Mode Entry BIST message received with Data Object BIST Shared Test Mode Exit PE_BIST_Shared Capacity_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Shared Capacity Test Mode1. PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected 1) The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off. The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs: Hard Reset, Cable Reset, Soft Reset, Data Role Swap, Power Role Swap, Fast Role Swap, VCONN Swap. The UUT May leave test mode if the tester makes a request that exceeds the capabilities of the UUT. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 965 8.3.3.28 USB Type-C Referenced States This section contains states cross-referenced from the [USB Type-C 2.4] specification. 8.3.3.28.1 ErrorRecovery state The ErrorRecovery state is used to electronically disconnect Port Partners using the USB Type-C connector. The ErrorRecovery state Shall be entered when there are errors on USB Type-C Ports which cannot be recovered by Hard Reset. The ErrorRecovery state Shall map to USB Type-C ErrorRecovery state operation as defined in the [USB Type-C 2.4] specification. Bus powered Sinks Shall Not be required to meet this requirement as removal of their power will serve the same purpose. On entry to the ErrorRecovery state the Explicit Contract and PD Connection Shall be ended. On exit from the ErrorRecovery state a new Explicit Contract Should be established once the Port Partners have re-connected over the CC wire. Page 966 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.29 Policy Engine States Table 8.154, "Policy Engine States" lists the states used by the various state machines. Table 8.154 Policy Engine States State name Reference SenderResponseTimer SRT_Stopped Section 8.3.3.1.1.1 SRT_Running Section 8.3.3.1.1.2 SRT_Expired Section 8.3.3.1.1.3 Source Port PE_SRC_Startup Section 8.3.3.2.1 PE_SRC_Discovery Section 8.3.3.2.2 PE_SRC_Send_Capabilities Section 8.3.3.2.3 PE_SRC_Negotiate_Capability Section 8.3.3.2.4 PE_SRC_Transition_Supply Section 8.3.3.2.5 PE_SRC_Ready Section 8.3.3.2.6 PE_SRC_Disabled Section 8.3.3.2.7 PE_SRC_Capability_Response Section 8.3.3.2.8 PE_SRC_Hard_Reset Section 8.3.3.2.9 PE_SRC_Hard_Reset_Received Section 8.3.3.2.10 PE_SRC_Transition_to_default Section 8.3.3.2.11 PE_SRC_Give_Source_Cap Section 8.3.3.2.15 PE_SRC_Get_Sink_Cap Section 8.3.3.2.12 PE_SRC_Wait_New_Capabilities Section 8.3.3.2.13 PE_SRC_EPR_Keep_Alive Section 8.3.3.2.14 Sink Port PE_SNK_Startup Section 8.3.3.3.1 PE_SNK_Discovery Section 8.3.3.3.2 PE_SNK_Wait_for_Capabilities Section 8.3.3.3.3 PE_SNK_Evaluate_Capability Section 8.3.3.3.4 PE_SNK_Select_Capability Section 8.3.3.3.5 PE_SNK_Transition_Sink Section 8.3.3.3.6 PE_SNK_Ready Section 8.3.3.3.7 PE_SNK_Hard_Reset Section 8.3.3.3.8 PE_SNK_Transition_to_default Section 8.3.3.3.9 PE_SNK_Give_Sink_Cap Section 8.3.3.3.10 PE_SNK_Get_Source_Cap Section 8.3.3.3.12 PE_SNK_EPR_Keep_Alive Section 8.3.3.3.11 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 967 Soft Reset and Protocol Error Source Port Soft Reset PE_SRC_Send_Soft_Reset Section 8.3.3.4.1.1 PE_SRC_Soft_Reset Section 8.3.3.4.1.2 Sink Port Soft Reset PE_SNK_Send_Soft_Reset Section 8.3.3.4.2.1 PE_SNK_Soft_Reset Section 8.3.3.4.2.2 Data Reset DFP Data Reset PE_DDR_Send_Data_Reset Section 8.3.3.5.1.1 PE_DDR_Data_Reset_Received Section 8.3.3.5.1.2 PE_DDR_Wait_For_VCONN_Off Section 8.3.3.5.1.3 PE_DDR_Perform_Data_Reset Section 8.3.3.5.1.4 UFP Data Reset PE_UDR_Send_Data_Reset Section 8.3.3.5.2.1 PE_UDR_Data_Reset_Received Section 8.3.3.5.2.2 PE_UDR_Turn_Off_VCONN Section 8.3.3.5.2.3 PE_UDR_Send_Ps_Rdy Section 8.3.3.5.2.4 PE_UDR_Wait_For_Data_Reset_Complete Section 8.3.3.5.2.5 Not Supported Message Source Port Not Supported PE_SRC_Send_Not_Supported Section 8.3.3.6.1.1 PE_SRC_Not_Supported_Received Section 8.3.3.6.1.2 PE_SRC_Chunk_Received Section 8.3.3.6.1.3 Sink Port Not Supported PE_SNK_Send_Not_Supported Section 8.3.3.6.2.1 PE_SNK_Not_Supported_Received Section 8.3.3.6.2.2 PE_SNK_Chunk_Received Section 8.3.3.6.2.3 Source Alert Source Port Source Alert PE_SRC_Send_Source_Alert Section 8.3.3.7.1.1 PE_SRC_Wait_for_Get_Status Section 8.3.3.7.1.2 Sink Port Source Alert PE_SNK_Source_Alert_Received Section 8.3.3.7.2.1 Sink Port Sink Alert PE_SNK_Send_Sink_Alert Section 8.3.3.7.3.1 PE_SNK_Wait_for_Get_Status Section 8.3.3.7.3.2 Source Port Sink Alert PE_SRC_Sink_Alert_Received Section 8.3.3.7.4.1 Table 8.154 Policy Engine States State name Reference Page 968 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Source/Sink Extended Capabilities Sink Port Get Source Capabilities Extended PE_SNK_Get_Source_Cap_Ext Section 8.3.3.8.1.1 Source Port Give Source Capabilities Extended PE_SRC_Give_Source_Cap_Ext Section 8.3.3.8.2.1 Source Port Get Sink Capabilities Extended PE_SRC_Get_Sink_Cap_Ext Section 8.3.3.8.3.1 Source Port Give Source Capabilities Extended PE_SNK_Give_Sink_Cap_Ext Section 8.3.3.8.4.1 Source Information Sink Port Get Source Information PE_SNK_Get_Source_Info Section 8.3.3.9.1.1 Source Port Give Source Information PE_SRC_Give_Source_Info Section 8.3.3.9.2.1 Status Get Status PE_Get_Status Section 8.3.3.10.1.1 Give Status PE_Give_Status Section 8.3.3.10.1.1 Sink Port Get PPS Status PE_SNK_Get_PPS_Status Section 8.3.3.10.3.1 Source Port Give PPS Status PE_SRC_Give_PPS_Status Section 8.3.3.10.4.1 Battery Capabilities Get Battery Capabilities PE_Get_Battery_Cap Section 8.3.3.11.1.1 Give Battery Capabilities PE_Give_Battery_Cap Section 8.3.3.11.2.1 Battery Status Get Battery Status PE_Get_Battery_Status Section 8.3.3.12.1.1 Give Battery Status PE_Give_Battery_Status Section 8.3.3.12.2.1 Manufacturer Information Get Manufacturer Information PE_Get_Manufacturer_Info Section 8.3.3.13.1.1 Give Manufacturer Information PE_Give_Manufacturer_Info Section 8.3.3.13.2.1 Country Codes and Information Get Country Codes PE_Get_Country_Codes Section 8.3.3.14.1.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 969 Give Country Codes PE_Give_Country_Codes Section 8.3.3.14.2.1 Get Country Information PE_Get_Country_Info Section 8.3.3.14.3.1 Give Country Information PE_Give_Country_Info Section 8.3.3.14.4.1 Revision Get Revision PE_Get_Revision Section 8.3.3.15.1.1 Give Revision PE_Give_Revision Section 8.3.3.15.2.1 Enter USB DFP Enter USB PE_DEU_Send_Enter_USB Section 8.3.3.16.1.1 UFP Enter USB PE_UEU_Enter_USB_Received Section 8.3.3.16.2.1 Security Request/Response Send Security Request PE_Send_Security_Request Section 8.3.3.17.1.1 Send Security Response PE_Send_Security_Response Section 8.3.3.17.2.1 Security Response Received PE_Security_Response_Received Section 8.3.3.17.3.1 Firmware Update Request/Response Send Firmware Update Request PE_Send_Firmware_Update_Request Section 8.3.3.18.1.1 Send Firmware Update Response PE_Send_Firmware_Update_Response Section 8.3.3.18.2.1 Firmware Update Response Received PE_Firmware_Update_Response_Received Section 8.3.3.18.3.1 Dual-Role Port DFP to UFP Data Role Swap PE_DRS_DFP_UFP_Evaluate_Swap Section 8.3.3.19.1.2 PE_DRS_DFP_UFP_Accept_Swap Section 8.3.3.19.1.3 PE_DRS_DFP_UFP_Change_to_UFP Section 8.3.3.19.1.4 PE_DRS_DFP_UFP_Send_Swap Section 8.3.3.19.1.5 PE_DRS_DFP_UFP_Reject_Swap Section 8.3.3.19.1.6 Table 8.154 Policy Engine States State name Reference Page 970 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 UFP to DFP Data Role Swap PE_DRS_UFP_DFP_Evaluate_Swap Section 8.3.3.19.2.2 PE_DRS_UFP_DFP_Accept_Swap Section 8.3.3.19.2.3 PE_DRS_UFP_DFP_Change_to_DFP Section 8.3.3.19.2.4 PE_DRS_UFP_DFP_Send_Swap Section 8.3.3.19.2.5 PE_DRS_UFP_DFP_Reject_Swap Section 8.3.3.19.2.6 Source to Sink Power Role Swap PE_PRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.3.2 PE_PRS_SRC_SNK_Accept_Swap Section 8.3.3.19.3.3 PE_PRS_SRC_SNK_Transition_to_off Section 8.3.3.19.3.4 PE_PRS_SRC_SNK_Assert_Rd Section 8.3.3.19.3.5 PE_PRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.3.6 PE_PRS_SRC_SNK_Send_Swap Section 8.3.3.19.3.7 PE_PRS_SRC_SNK_Reject_Swap Section 8.3.3.19.3.8 Sink to Source Power Role Swap PE_PRS_SNK_SRC_Evaluate_Swap Section 8.3.3.19.4.2 PE_PRS_SNK_SRC_Accept_Swap Section 8.3.3.19.4.3 PE_PRS_SNK_SRC_Transition_to_off Section 8.3.3.19.4.4 PE_PRS_SNK_SRC_Assert_Rp Section 8.3.3.19.4.5 PE_PRS_SNK_SRC_Source_on Section 8.3.3.19.4.6 PE_PRS_SNK_SRC_Send_Swap Section 8.3.3.19.4.7 PE_PRS_SNK_SRC_Reject_Swap Section 8.3.3.19.4.8 Source to Sink Fast Role Swap PE_FRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.5.2 PE_FRS_SRC_SNK_Accept_Swap Section 8.3.3.19.5.3 PE_FRS_SRC_SNK_Transition_to_off Section 8.3.3.19.5.4 PE_FRS_SRC_SNK_Assert_Rd Section 8.3.3.19.5.5 PE_FRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.5.6 Sink to Source Fast Role Swap PE_FRS_SNK_SRC_Start_AMS Section 8.3.3.19.6.1 PE_FRS_SNK_SRC_Send_Swap Section 8.3.3.19.6.2 PE_FRS_SNK_SRC_Transition_to_off Section 8.3.3.19.6.3 PE_FRS_SNK_SRC_VBUS_Applied Section 8.3.3.19.6.4 PE_FRS_SNK_SRC_Assert_Rp Section 8.3.3.19.6.5 PE_FRS_SNK_SRC_Source_on Section 8.3.3.19.6.6 Dual-Role Source Port Get Source Capabilities PE_DR_SRC_Get_Source_Cap Section 8.3.3.19.7.1 Dual-Role Source Port Give Sink Capabilities PE_DR_SRC_Give_Sink_Cap Section 8.3.3.19.8.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 971 Dual-Role Sink Port Get Sink Capabilities PE_DR_SNK_Get_Sink_Cap Section 8.3.3.19.9.1 Dual-Role Sink Port Give Source Capabilities PE_DR_SNK_Give_Source_Cap Section 8.3.3.19.10.1 Dual-Role Source Port Get Source Capabilities Extended PE_DR_SRC_Get_Source_Cap_Ext Section 8.3.3.19.11.1 Dual-Role Sink Port Give Source Capabilities Extended PE_DR_SNK_Give_Source_Cap_Ext Section 8.3.3.19.12.1 Dual-Role Sink Port Get Sink Capabilities Extended PE_DR_SNK_Get_Sink_Cap_Ext Section 8.3.3.19.13.1 Dual-Role Source Port Give Sink Capabilities Extended PE_DR_SRC_Give_Sink_Cap_Ext Section 8.3.3.19.14.1 Dual-Role Source Port Get Source Information PE_DR_SRC_Get_Source_Info Section 8.3.3.19.15.1 Dual-Role Sink Port Give Source Information PE_DR_SNK_Give_Source_Info Section 8.3.3.19.16.1 USB Type-C VCONN Swap PE_VCS_Send_Swap Section 8.3.3.20.1 PE_VCS_Evaluate_Swap Section 8.3.3.20.2 PE_VCS_Accept_Swap Section 8.3.3.20.3 PE_VCS_Reject_Swap Section 8.3.3.20.4 PE_VCS_Wait_For_VCONN Section 8.3.3.20.5 PE_VCS_Turn_Off_VCONN Section 8.3.3.20.6 PE_VCS_Turn_On_VCONN Section 8.3.3.20.7 PE_VCS_Send_Ps_Rdy Section 8.3.3.20.8 PE_VCS_Force_VCONN Section 8.3.3.20.9 Initiator Structured VDM Initiator to Port Structured VDM Discover Identity PE_INIT_PORT_VDM_Identity_Request Section 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_ACKed Section 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_NAKed Section 8.3.3.21.1.3 Initiator Structured VDM Discover SVIDs PE_INIT_VDM_SVIDs_Request Section 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_ACKed Section 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_NAKed Section 8.3.3.21.2.3 Initiator Structured VDM Discover Modes PE_INIT_VDM_Modes_Request Section 8.3.3.21.3.1 PE_INIT_VDM_Modes_ACKed Section 8.3.3.21.3.2 PE_INIT_VDM_Modes_NAKed Section 8.3.3.21.3.3 Table 8.154 Policy Engine States State name Reference Page 972 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Initiator Structured VDM Attention PE_INIT_VDM_Attention_Request Section 8.3.3.21.4.1 Responder Structured VDM Responder Structured VDM Discovery Identity PE_RESP_VDM_Get_Identity Section 8.3.3.22.1.1 PE_RESP_VDM_Send_Identity Section 8.3.3.22.1.2 PE_RESP_VDM_Get_Identity_NAK Section 8.3.3.22.1.3 Responder Structured VDM Discovery SVIDs PE_RESP_VDM_Get_SVIDs Section 8.3.3.22.2.1 PE_RESP_VDM_Send_SVIDs Section 8.3.3.22.2.2 PE_RESP_VDM_Get_SVIDs_NAK Section 8.3.3.22.2.3 Responder Structured VDM Discovery Modes PE_RESP_VDM_Get_Modes Section 8.3.3.22.3.1 PE_RESP_VDM_Send_Modes Section 8.3.3.22.3.2 PE_RESP_VDM_Get_Modes_NAK Section 8.3.3.22.3.3 Receiving a Structured VDM Attention PE_RCV_VDM_Attention_Request Section 8.3.3.22.4.1 DFP Structured VDM DFP Structured VDM Mode Entry PE_DFP_VDM_Mode_Entry_Request Section 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_ACKed Section 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_NAKed Section 8.3.3.23.1.3 DFP Structured VDM Mode Exit PE_DFP_VDM_Mode_Exit_Request Section 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_ACKed Section 8.3.3.23.2.2 UFP Structure VDM UFP Structured VDM Enter Mode PE_UFP_VDM_Evaluate_Mode_Entry Section 8.3.3.24.1.1 PE_UFP_VDM_Mode_Entry_ACK Section 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_NAK Section 8.3.3.24.1.3 UFP Structured VDM Exit Mode PE_UFP_VDM_Mode_Exit Section 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit_ACK Section 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_NAK Section 8.3.3.24.2.3 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 973 Cable Plug Specific Cable Ready PE_CBL_Ready Section 8.3.3.25.1.1 Mode Entry PE_CBL_Evaluate_Mode_Entry Section 8.3.3.25.4.1.1 PE_CBL_Mode_Entry_ACK Section 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_NAK Section 8.3.3.25.4.1.3 Mode Exit PE_CBL_Mode_Exit Section 8.3.3.25.4.2.1 PE_CBL_Mode_Exit_ACK Section 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_NAK Section 8.3.3.25.4.1.3 Cable Soft Reset PE_CBL_Soft_Reset Section 8.3.3.25.2.1.1 Cable Hard Reset PE_CBL_Hard_Reset Section 8.3.3.25.2.2.1 DFP/VCONN Source Soft Reset or Cable Reset PE_DFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Cable_Reset Section 8.3.3.25.2.3.2 UFP/VCONN Source Soft Reset or Cable Reset PE_UFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.4.1 Source Startup Structured VDM Discover Identity PE_SRC_VDM_Identity_Request Section 8.3.3.25.3.1 PE_SRC_VDM_Identity_ACKed Section 8.3.3.25.3.2 PE_SRC_VDM_Identity_NAKed Section 8.3.3.25.3.3 EPR Mode Source EPR Mode Entry PE_SRC_Evaluate_EPR_Mode_Entry Section 8.3.3.26.1.1 PE_SRC_EPR_Mode_Entry_Ack Section 8.3.3.26.1.2 PE_SRC_EPR_Mode_Discover_Cable Section 8.3.3.26.1.3 PE_SRC_EPR_Mode_Evaluate_Cable_EPR Section 8.3.3.26.1.4 PE_SRC_EPR_Mode_Entry_Succeeded Section 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Failed Section 8.3.3.26.1.6 Sink EPR Mode Entry PE_SNK_Send_EPR_Mode_Entry Section 8.3.3.26.2.1 PE_SNK_EPR_Mode_Wait_For_Response Section 8.3.3.26.2.2 Source EPR Mode Exit PE_SRC_Send_EPR_Mode_Exit Section 8.3.3.26.3.1 PE_SRC_EPR_Mode_Exit_Received Section 8.3.3.26.3.2 Table 8.154 Policy Engine States State name Reference Page 974 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Sink EPR Mode Exit PE_SNK_Send_EPR_Mode_Exit Section 8.3.3.26.4.1 PE_SNK_EPR_Mode_Exit_Received Section 8.3.3.26.4.2 BIST BIST Carrier Mode PE_BIST_Carrier_Mode Section 8.3.3.27.1.1 BIST Carrier Mode PE_BIST_Test_Mode Section 8.3.3.27.2.1 BIST Shared Capacity Test Mode PE_BIST_Shared_Capacity_Test_Mode Section 8.3.3.27.3.1 USB Type-C referenced states ErrorRecovery Section 8.3.3.28.1 Table 8.154 Policy Engine States State name Reference
9 - States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 975)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 975 9 States and Status Reporting 9.1 Overview This chapter describes the Status reporting mechanisms for devices with data connections (e.g., D+/D- and or SSTx+/- and SSRx+/-). It also describes the corresponding USB state a device that supports USB PD Shall transition to as a result of changes to the USB PD state that the device is in. This chapter does not define the System Policy or the System Policy Manager. That is defined in [UCSI]. In addition, the Policies themselves are not described here; these are left to the implementers of the relevant products and systems to define. All PD Capable USB (PDUSB) Devices Shall report themselves as self-powered devices (over USB) when plugged into a PD capable Port even if they are entirely powered from VBUS. However, there are some differences between PD and [USB 2.0] / [USB 3.2]; for example, the presence of VBUS alone does not mean that the device (Consumer) moves from the USB Attached State to the USB Powered State. Similarly, the removal of VBUS alone does not move the device (Consumer) from any of the USB states to the USB Attached State. See Section 9.1.2, "Mapping to USB Device States" for details. PDUSB Devices Shall follow the PD requirements when it comes to suspend (see Section 6.4.1.2.1.2, "USB Suspend Supported"), configured, and operational power. The PD requirements when the device is configured or operational are defined in this section (see Table 9.4, "PD Consumer Port Descriptor"). Note: The power requirements reported in the PD Consumer Port descriptor of the device Shall override the power draw reported in the bMaxPower field in the configuration descriptor. A PDUSB Device Shall report zero in the bMaxPower field after successfully negotiating a mutually agreeable Explicit Contract and Shall disconnect and re-enumerate when it switches operation back to operating in standard [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. When operating in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] mode it Shall report its power draw via the bMaxPower field. Each Provider and Consumer will have their own Local Policies which operate between Port Partners. An example of a typical PD system is shown in Figure 9.1, "Example PD Topology". This example consists of a Provider, Consumer/Providers and Consumers connected together in a tree topology. Between directly connected devices there is both a flow of Power and also Communication consisting of both Status and Control information. Page 976 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.1 Example PD Topology Consumer Consumer Consumer/ Provider Consumer/ Provider Provider AC/Battery AC/Battery Power PD Communication P/C P/C P/C P/C Provider/Consumer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 977 Figure 9.2, "Mapping of PD Topology to USB" shows how this same topology can be mapped to USB. Figure 9.2 Mapping of PD Topology to USB Device Device Device Root Hub AC/Battery AC/Battery Power PD Communication Hub Page 978 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 In a USB based system, policy is managed by the host and communication of system level policy information is via standard USB data line communication. This is a separate mechanism to the USB Power Delivery VBUS protocol which is used to manage Local Policy. When USB Communication is used, status information and control requests are passed directly between the System Policy Manager (SPM) on the host and the Provider or Consumer. See Figure 9.3, "Use of SPM in the PD System". Figure 9.3 Use of SPM in the PD System Status information comes from a Provider or Consumer to the SPM so it can better manage the resources on the host and provide feedback to the end user. Real systems will be a mixture of devices which in terms of power management support might have implemented PD, [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] or they might even just be non-compliant “power sucking devices”. The level of communication of system status to the SPM will therefore not necessarily be comprehensive. The aim of the status mechanisms described here is to provide a mechanism whereby each connected entity in the system provides as much information as possible on the status of itself. Information described in this section that is communicated to the SPM is as follows:  Versions of USB Type-C®, PD and BC supported.  Capabilities as a Provider/Consumer.  Current operational state of each Port e.g. Standard, USB Type-C Current, BC, PD and Negotiated power level.  Status of AC or Battery Power for each PDUSB Device in the system. The SPM can Negotiate with Providers or Consumers in the system in order to request a different Local Policy, or to request the amount of power to be delivered by the Provider to the Consumer. Any change in Local Policy could Device Device Device Host (SPM) AC/Battery AC/Battery Power PD Communication USB Communication Hub Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 979 trigger a Re-negotiation of the Explicit Contract, using USB Power Delivery protocols, between a directly connected Provider and Consumer. A change in how much power is available can, for example, cause a Re-negotiation. 9.1.1 PDUSB Device and Hub Requirements All PDUSB Devices Shall return all relevant descriptors mentioned in this chapter. PDUSB Hubs Shall also support a PD bridge as defined in [UCSI]. Page 980 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.2 Mapping to USB Device States As mentioned in Section 9.1, "Overview" a PDUSB Device reports itself as a self-powered device. However, the device Shall determine whether or not it is in the USB Attached State or USB Powered States as described in Figure 9.4, "USB Attached to USB Powered State Transition", Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" and Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" All other USB states of the PDUSB Device Shall be as described in Chapter 9 of [USB 2.0] and [USB 3.2]. Figure 9.4, "USB Attached to USB Powered State Transition" shows how a PDUSB Device determines when to transition from the USB Attached State to the USB Powered State. USB Type-C Dead Battery operation does not require special handling since the default state at Attach or after a Hard Reset is that the USB Device is a Sink. Figure 9.4 USB Attached to USB Powered State Transition Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Consumer. A PDUSB Device determines that it is performing a Power Role Swap as described in Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present No Yes Can enumerate? Yes Device is a Source? Attached Sink? USB Attached Yes Device in Sink Mode No Negotiate enough Power? No USB Powered No No Yes Device in Source Mode (5V) Yes Hard Reset Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 981 Figure 9.5 Any USB State to USB Attached State Transition (When operating as a Consumer) Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Provider. Figure 9.6 Any USB State to USB Attached State Transition (When operating as a Provider) Figure 9.7, "Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap)" shows how a PDUSB Device using the USB Type-C connector determines when to transition from the USB Powered State to the USB Attached State after a Data Role Swap has been performed i.e., it has just changed from operation as a PDUSB Host to operation as a PDUSB Device. The Data Role Swap is described in Section 6.3.9, "DR_Swap Message". A Hard Reset will also return a Sink acting as a PDUSB Host to PDUSB Device operation as described in Section 6.8.3, "Hard Reset". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present Yes No Swapping Power Roles? Any USB State USB Attached Yes No Hard Reset and Can Operate Hard Reset and Can’t Operate Hard Reset and Bus Powered Lack of PD comms? No Yes Any USB State USB Attached Local Power Source Lost Hard Reset Page 982 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.7 Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap) VBUS Present Yes Swapping Data Roles? Any USB State USB Attached No Yes Hard Reset Changes Data Role Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 983 9.1.3 PD Software Stack Figure 9.8, "Software stack on a PD aware OS" gives an example of the software stack on a PD aware OS. In this stack we are using the example of a system with an xHCI based controller. The USB Power Delivery hardware May or May Not be a part of the xHC. Figure 9.8 Software stack on a PD aware OS Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager Page 984 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.4 PDUSB Device Enumeration As described earlier, a PDUSB Device acts as a self-powered device with some caveats with respect to how it transitions from the USB Attached State to USB Powered State. Figure 9.9, "Enumeration of a PDUSB Device" gives a high-level overview of the enumeration steps involved due to this change. A PDUSB Device will first (Step1) interact with the Power Delivery hardware and the Local Policy manager to determine whether or not it can get sufficient power to enumerate/operate. PD is likely to have established a Explicit Contract prior to enumeration. The SPM will be notified (Step 2) of the result of this Negotiation between the Power Delivery hardware and the PDUSB Device. After successfully negotiating a mutually agreeable Explicit Contract the device will signal a connect to the xHC. The standard USB enumeration process (Steps 3, 4 and 5) is then followed to load the appropriate driver for the function(s) that the PDUSB Device exposes. Figure 9.9 Enumeration of a PDUSB Device If a PDUSB Device cannot perform its intended function with the amount of power that it can get from the Port it is connected to, then the host system Should display a notification (on a PD aware OS) about the failure to provide sufficient power to the device. In addition, the device Shall follow the requirements listed in Section 8.2.5.2.1, "Local device handling of mismatch". Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager 5 4 3 2 1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 985 9.2 PD Specific Descriptors A PDUSB Device Shall return all relevant descriptors mentioned in this section. The device Shall return its capability descriptors as part of the device's Binary Object Store (BOS) descriptor set. Table 9.1, "USB Power Delivery Type Codes" lists the type of PD device capabilities. Table 9.1 USB Power Delivery Type Codes Capability Code Value Description POWER_DELIVERY_CAPABILITY 06H Defines the various PD Capabilities of this device BATTERY_INFO_CAPABILITY 07H Provides information on each Battery supported by the device PD_CONSUMER_PORT_CAPABILITY 08H The Consumer characteristics of a Port on the device PD_PROVIDER_PORT_CAPABILITY 09H The Provider characteristics of a Port on the device Page 986 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.1 USB Power Delivery Capability Descriptor Table 9.2, "USB Power Delivery Capability Descriptor" details the fields in the USB POWER_DELIVERY_CAPABILITY Descriptor. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: POWER_DELIVERY_CAPABILITY 3 bReserved 1 Reserved Shall be set to zero. 4 bmAttributes 4 Bitmap Bitmap encoding of supported device level features. A value of one in a bit location indicates a feature is supported; a value of zero indicates it is not supported. Encodings are: Bit Description 0 Reserved. Shall be set to zero. 1 Battery Charging. This bit Shall be set to one to indicate this device supports [USBBC 1.2] as per the value reported in the bcdBCVersion field. 2 USB Power Delivery. This bit Shall be set to one to indicate this device supports the USB Power Delivery Specification as per the value reported in the bcdPDVersion field. 3 Provider. This bit Shall be set to one to indicate this device is capable of providing power. This field is only Valid if Bit 2 is set to one. 4 Consumer. This bit Shall be set to one to indicate that this device is a consumer of power. This field is only Valid if Bit 2 is set to one. 5 This bit Shall be set to 1 to indicate that this device supports the feature CHARGING_POLICY. Note: Supporting the CHARGING_POLICY feature does not require a BC or PD mechanism to be implemented. 6 USB Type-C Current. This bit Shall be set to one to indicate this device supports power capabilities defined in[USB Type-C 2.4] as per the value reported in the bcdUSBTypeCVersion field 7 Reserved. Shall be set to zero. 15:8 bmPowerSource. At least one of the following bits 8, 9 and 14 Shall be set to indicate which power sources are supported. Bit Description 8 AC Supply 9 Battery 10 Other 13:11 NumBatteries. This field Shall only be Valid when the Battery field is set to one and Shall be used to report the number of batteries in the device. 14 Uses VBUS 15 Reserved and Shall be set to zero. 13:16 Reserved. Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 987 9.2.2 Battery Info Capability Descriptor A PDUSB Device Shall support the capability descriptor shown in Table 9.3, "Battery Info Capability Descriptor" if it reported that one of its power sources was a Battery in the bmPowerSource field in its Power Deliver Capability Descriptor. It Shall return one BATTERY_INFO_CAPABILITY Descriptor per Battery it supports. 8 bcdBCVersion 2 BCD Battery Charging Specification Release Number in Binary-Coded Decimal (e.g., V1.20 is 120H). This field Shall only be Valid if the device indicates that it supports [USBBC 1.2] in the bmAttributes field. 10 bcdPDVersion 2 BCD USB Power Delivery Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports PD in the bmAttributes field. 12 bcdUSBTypeCVersion 2 BCD USB Type-C Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports USB Type-C in the bmAttributes field. Table 9.3 Battery Info Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: BATTERY_INFO_CAPABILITY 3 iBattery 1 Index Index of string descriptor Shall contain the user-friendly name for this Battery. 4 iSerial 1 Index Index of string descriptor Shall contain the Serial Number String for this Battery. 5 iManufacturer 1 Index Index of string descriptor Shall contain the name of the Manufacturer for this Battery. 6 bBatteryId 1 Number Value Shall be used to uniquely identify this Battery in status Messages. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 dwChargedThreshold 4 mWh Shall contain the Battery charge value above which this Battery is considered to be fully charged but not necessarily “topped off.” 12 dwWeakThreshold 4 mWh Shall contain the minimum charge level of this Battery such that above this threshold, a device can be assured of being able to power up successfully (see [USBBC 1.2]). 16 dwBatteryDesignCapacity 4 mWh Shall contain the design capacity of the Battery. 20 dwBatteryLastFullchargeCapacity 4 mWh Shall contain the maximum capacity of the Battery when fully charged. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description Page 988 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.3 PD Consumer Port Capability Descriptor A PDUSB Device Shall support the PD_CONSUMER_PORT_CAPABILITY descriptor shown in Table 9.4, "PD Consumer Port Descriptor" if it is a Consumer. Table 9.4 PD Consumer Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_CONSUMER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Consumer Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 wMinVoltage 2 Number Shall contain the minimum voltage in 50mV units that this Consumer is capable of operating at. 8 wMaxVoltage 2 Number Shall contain the maximum voltage in 50mV units that this Consumer is capable of operating at. 10 wReserved 2 Number Reserved and Shall be set to zero. 12 dwMaxOperatingPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw when it is in a steady state operating mode. 16 dwMaxPeakPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw for a short duration of time (dwMaxPeakPowerTime) before it falls back into a steady state. 20 dwMaxPeakPowerTime 4 Number Shall contain the time in 100ms units that this Consumer can draw peak current. A device Shall set this field to 0xFFFF if this value is unknown. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 989 9.2.4 PD Provider Port Capability Descriptor A PDUSB Device Shall support the PD_PROVIDER_PORT_CAPABILITY descriptor shown in Table 9.5, "PD Provider Port Descriptor" if it is a Provider. Table 9.5 PD Provider Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_PROVIDER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Provider Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 bNumOfPDObjects 1 Number Shall indicate the number of Power Data Objects. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 wPowerDataObject1 4 Bitmap Shall contain the first Power Data Object supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. ... ... ... ... ... 4*(N+1) wPowerDataObjectN 4 Bitmap Shall contain the 2nd and subsequent Power Data Objects supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. Page 990 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.3 PD Specific Requests and Events A PDUSB Device that is compliant to this specification Shall support the Battery related requests if it has a Battery. A PDUSB Hub that is compliant to this specification Shall support a USB PD Bridge as described in [UCSI] irrespective of whether the PDUSB Hub is a Provider, a Consumer, or both. 9.3.1 PD Specific Requests PD defines requests to which PDUSB Devices Shall respond as outlined in Table 9.6, "PD Requests". All Valid requests in Table 9.6, "PD Requests" Shall be implemented by PDUSB Devices. Table 9.7, "PD Request Codes" gives the bRequest values for Commands that are not listed in the hub/device framework chapters of [USB 2.0], [USB 3.2]. Table 9.8, "PD Feature Selectors" gives the Valid feature selectors for the PD class. Refer to Section 9.4.2.1, "BATTERY_WAKE_MASK Feature Selector", and Section 9.4.2.2, "CHARGING_POLICY Feature Selector" for a description of the features. Table 9.6 PD Requests Request bmRequestType bRequest wValue wIndex wLength Data GetBatteryStatus 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status SetPDFeature 00000000B set_feature Feature Selector Feature Specific Zero None Table 9.7 PD Request Codes bRequest Value GET_BATTERY_STATUS 21 Table 9.8 PD Feature Selectors Feature Selector Recipient Value BATTERY_WAKE_MASK Device 40 CHARGING_POLICY Device 54 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 991 9.4 PDUSB Hub and PDUSB Peripheral Device Requests 9.4.1 GetBatteryStatus The request shown in Table 9.9, "Get Battery Status Request" returns the current status of the Battery in a PDUSB Hub/Peripheral, with Battery Status information as shown in Table 9.10, "Battery Status Structure". Table 9.9 Get Battery Status Request bmRequestType bRequest wValue wIndex wLength Data 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status Table 9.10 Battery Status Structure Offset Field Size Value Description 0 bBatteryAttributes 1 Number Shall indicate whether a Battery is installed and whether this is charging or discharging. Value Description 0 There is no Battery 1 The Battery is charging 2 The Battery is discharging 3 The Battery is neither discharging nor charging 255...4 Reserved and Shall Not be used 1 bBatterySOC 1 Number Shall indicate the Battery State of Charge given as percentage value from Battery Remaining Capacity. 2 bBatteryStatus 1 Number If a Battery is present Shall indicate the present status of the Battery. Value Description 0 No error 1 Battery required and not present 2 Battery non-chargeable/wrong chemistry 3 Over-temp shutdown 4 Over-voltage shutdown 5 Over-current shutdown 6 Fatigued Battery 7 Unspecified error 255...8 Reserved and Shall Not be used Page 992 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 If wValue or wLength are not as specified above, then the behavior of the PDUSB Device is not specified. If wIndex refers to a Battery that does not exist, then the PDUSB Device Shall respond with a Request Error. If the PDUSB Device is not configured, the PDUSB Hub's response to this request is undefined. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. 9.4.2 SetPDFeature The request shown in Table 9.11, "Set PD Feature" sets the value requested in the PDUSB Hub/Peripheral. Setting a feature enables that feature or starts a process associated with that feature; see Table 9.8, "PD Feature Selectors" for the feature selector definitions. Features that May be set with this request are:  BATTERY_WAKE_MASK.  CHARGING_POLICY. 3 bRemoteWakeCapStatus 1 Bitmap If the device supports remote wake, then the device Shall support Battery Remote wake events. The default value for the Remote wake events Shall be turned off (set to zero) and can be enable/disabled by the host as required. If set to one the device Shall generate a wake event when a change of status occurs. See Section 9.4.2, "SetPDFeature" for more details. Value Description 0 Battery present event 1 Charging flow 2 Battery error 7:3 Reserved and Shall be set to zero 4 wRemainingOperatingTime 2 Number Shall contain the operating time (in minutes) until the Weak Battery threshold is reached, based on Present Battery Strength and the device's present operational power needs. Note: This value Shall exclude any additional power re- ceived from charging. A Battery that is not capable of returning this information Shall return a value of 0xFFFF. 6 wRemainingChargeTime 2 Number Shall contain the remaining time (in minutes) until the Charged Battery threshold is reached based on Present Battery Strength, charging power and the device's present operational power needs. Value Shall only be Valid if the Charging Flow is "Charging". A Battery that is not capable of returning this information Shall return a value of 0xFFFF. Table 9.11 Set PD Feature bmRequestType bRequest wValue wIndex wLength Data 00000000B set_ feature Feature Selector Feature Specific Zero None Table 9.10 Battery Status Structure Offset Field Size Value Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 993 9.4.2.1 BATTERY_WAKE_MASK Feature Selector When the feature selector is set to BATTERY_WAKE_MASK, then the wIndex field is structured as shown in Table 9.12, "Battery Wake Mask". The SPM May Enable or Disable the wake events associated with one or more of the above events by using this feature. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. Table 9.12 Battery Wake Mask Bit Description 0 Battery Present: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery has been inserted. 1 Charging Flow: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery switched from charging to discharging or vice versa. 2 Battery Error: When this bit is set then the PDUSB Device Shall generate a wake event if the Battery has detected an error condition. 15:3 Reserved and Shall Not be used Page 994 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.4.2.2 CHARGING_POLICY Feature Selector When the feature selector is set to CHARGING_POLICY, the wIndex field Shall be set to one of the values defined in Table 9.13, "Charging Policy Encoding". If the device is using USB Type-C Current above the default value or is using PD then this feature setting has no effect and the rules for power levels specified in the [USB Type-C 2.4] or USB PD specifications Shall apply. This is a Valid Command for the PDUSB Hub/Peripheral in the Address or Configured USB states. Further, it is only Valid if the device reports a USB PD capability descriptor in its BOS descriptor and Bit 5 of the bmAttributes in that descriptor is set to 1. The device will go back to the wIndex default value of 0 whenever it is reset. Table 9.13 Charging Policy Encoding Value Description 00H The device Shall follow the default current limits as defined in the USB 2.0 or USB 3.1 specification, or as negotiated through other USB mechanisms such as BC. This is the default value. 01H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCHPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 02H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCLPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 03H The device Shall Not consume any current for charging the device itself regardless of its USB state. 04H-FFFFH Reserved and Shall Not be used
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Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 995 10 Power Rules 10.1 Introduction The flexibility of power provision on USB Type-C® is expected to lead to power adapter re-use and the increasingly widespread provision of USB power outlets in domestic and public places and in transport of all kinds. Environmental considerations could result in unbundled power adapters. Rules are needed to avoid incompatibility between the Sources and the Sinks they are used to power, in order to avoid user confusion and to meet user expectations. This section specifies a set of rules that Sources and Sinks Shall follow. These rules provide a simple and consistent user experience. The PDP Rating is a manufacturer declared value placed on packaging to help the user understand the capabilities of a Charger or the size of Charger required to power their device. For PDP values of 10W and above the PDP Shall be declared as an integer number of Watts. For PDP values less than 10W, the PDP Shall be declared in increments of 0.5W. The Source Power Rules define a PDP to provide a simple way to tell the user about the capabilities of their power adapter or device. PDP Rating is akin to the wattage rating of a light bulb - bigger numbers mean more capability. The Sink Power Rules define a PDP to provide a simple way to tell the user which Sources will provide adequate power for their Sink. 10.2 Source Power Rules The Source Power Rules defined in this section include both Normative and Optional rules. For all of the defined rules, the capabilities a Source exposes are based on the Port Maximum PDP, or if power constrained, the Port Present PDP of the Port. For a Guaranteed Capability Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Maximum PDP and Mode of operation (i.e., SPR Mode or EPR Mode). For a Managed Capability Port, except before the First Explicit Contract or before the Explicit Contract after the Port Present PDP changes on a Shared Capacity Charger Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Present PDP and Mode of operation (i.e., SPR Mode or EPR Mode). After the First Explicit Contract, this requirement assures that the attached Sink will always know what voltages (or voltage modes) are presently available from the Source. In order to meet the expectations of the user, the Maximum Current/Power in the Source Capabilities PDO or APDO for Sources with a PDP Rating of x Watts Shall be as follows:  Maximum current for Normative and Optional Fixed Supply/Variable Supply PDOs Shall be either RoundUp(x/voltage) or RoundDown(x/voltage) to the nearest 10mA.  Maximum current for SPR Programmable Power Supply APDOs Shall be as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". Note: When the Constant Power bit is set in the APDO, the programmable power supply's output current is as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" however the programmable power supply will limit its output current so that the product of its actual output voltage times the output current does not exceed the PDP.  If a 9V Prog, 15V Prog or 20V Prog Programmable Power Supply APDO is Advertised when not required by Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP", then the maximum current Shall be RoundDown (x/Prog Voltage) to the nearest 50mA. When the PPS Power Limited bit is clear the Source Shall provide this current at Maximum Voltage.  Maximum power for Optional Battery Supply PDOs Shall be ≤ x.
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Page 114 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6 Protocol Layer 6.1 Overview This chapter describes the requirements of the USB Power Delivery Specification's Protocol Layer including:  Details of how Messages are constructed and used.  Use of timers and timeout values.  Use of Message and retry counters.  Reset operation.  Error handling.  State behavior. Refer to Section 2.6, "Architectural Overview" for an overview of the theory of operation of USB Power Delivery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 115 6.2 Messages This specification defines three types of Messages:  Control Messages that are short and used to manage the Message flow between Port Partners or to exchange Messages that require no additional data. Control Messages are 16 bits in length.  Data Messages that are used to exchange information between a pair of Port Partners. Data Messages range from 48 to 240 bits in length.  Some examples of Data Messages are:  Those used to expose Capabilities and Negotiate power.  Those used for the BIST.  Those that are Vendor Defined Messages.  Extended Messages that are used to exchange information between a pair of Port Partners. Extended Messages are up to MaxExtendedMsgLen bytes.  Some examples of Extended Messages are:  Those used for Source and Battery information.  Those used for Security.  Those used for Firmware Update.  Those that are Vendor Defined Extended Messages. 6.2.1 Message Construction All Messages Shall be composed of a Message Header and a variable length (including zero) data portion. A Message either originates in the Protocol Layer and is passed to the PHY Layer, or it is received by the PHY Layer and is passed to the Protocol Layer. Figure 6.1, "USB Power Delivery Packet Format for a Control Message" illustrates a Control Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.1 USB Power Delivery Packet Format for a Control Message Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload" illustrates a Data Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Legend: PHY Layer Protocol Layer Page 116 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.2 USB Power Delivery Packet Format including Data Message Payload Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" illustrates an Extended Message as part of a Packet showing the parts are provided by the Protocol Layer and PHY Layer. Figure 6.3 USB Power Delivery Packet Format including an Extended Message Header and Payload 6.2.1.1 Message Header Every Message Shall start with a Message Header as shown in:  Figure 6.1, "USB Power Delivery Packet Format for a Control Message"  Figure 6.2, "USB Power Delivery Packet Format including Data Message Payload"  Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and as defined in Table 6.1, "Message Header". The Message Header contains basic information about the Message and the PD Port Capabilities. The Message Header May be used standalone as a Control Message when the Number of Data Objects field is zero or as the first part of a Data Message when the Number of Data Objects field is non-zero. 6.2.1.1.1 Extended The 1-bit Extended field Shall be set to zero to indicate a Control Message or Data Message and set to one to indicate an Extended Message. Table 6.1 Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Extended Section 6.2.1.1.1 14…12 SOP* Number of Data Objects Section 6.2.1.1.2 11…9 SOP* MessageID Section 6.2.1.1.3 8 SOP only Port Power Role Section 6.2.1.1.4 SOP’/SOP’’ Cable Plug Section 6.2.1.1.7 7…6 SOP* Specification Revision Section 6.2.1.1.5 5 SOP only Port Data Role Section 6.2.1.1.6 SOP’/SOP’’ Reserved Section 1.4.2 4…0 SOP* Message Type Section 6.2.1.1.8 Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) 0..7 Data Object(s) Legend: PHY Layer Protocol Layer Preamble SOP* (Start Of Packet) CRC EOP (End Of Packet) Message Header (16 bit) Data (0..260 bytes) Legend: PHY Layer Protocol Layer Extended Message Header (16 bit) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 117 The Extended field Shall apply to all SOP* Packet types. 6.2.1.1.2 Number of Data Objects When the Extended field is set to zero the 3-bit Number of Data Objects field Shall indicate the number of 32-bit Data Objects that follow the Message Header. When this field is zero the Message is a Control Message and when it is non-zero, the Message is a Data Message. The Number of Data Objects field Shall apply to all SOP* Packet types. When both the Extended bit and Chunked bit are set to one, the Number of Data Objects field Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. When the Extended bit is set to one and Chunked bit is set to zero, the Number of Data Objects field Shall be Reserved. Note: In this case, the Message length is determined solely by the Data Size field in the Extended Message Header. 6.2.1.1.3 MessageID The 3-bit MessageID field is the value generated by a rolling counter maintained by the originator of the Message. The MessageIDCounter Shall be initialized to zero at power-on as a result of a Soft Reset, or a Hard Reset. The MessageIDCounter Shall be incremented when a Message is successfully received as indicated by receipt of a GoodCRC Message. Note: The usage of MessageID during testing with BIST Messages is defined in [USBPDCompliance]. The MessageID field Shall apply to all SOP* Packet types. 6.2.1.1.4 Port Power Role The 1-bit Port Power Role field Shall indicate the Port's present Power Role:  0b Sink  1b Source Messages, such as Get_Sink_Cap_Extended, that are only ever sent by a Source, Shall always have the Port Power Role field set to Source. Similarly, Messages such as the Request Message that are only ever sent by a Sink Shall always have the Port Power Role field set to Sink. During the Power Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that the Initial Source's power supply is turned off (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Power Role Swap AMS, for the Initial Sink, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" and Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Source Port, the Port Power Role field Shall be set to Sink in the PS_RDY Message indicating that VBUS is not being driven by the Initial Source and is within vSafe5V (see Figure 8.39, "Successful Fast Role Swap Sequence"). During the Fast Role Swap AMS, for the Initial Sink Port, the Port Power Role field Shall be set to Source for Messages initiated by the Policy Engine after receiving the PS_RDY Message from the Initial Source (see Figure 8.39, "Successful Fast Role Swap Sequence"). Note: The GoodCRC Message sent by the Initial Sink in response to the PS_RDY Message from the Initial Source will have its Port Power Role field set to Sink since this is initiated by the Protocol Layer. Subsequent Page 118 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Messages initiated by the Policy Engine, such as the PS_RDY Message sent to indicate that VBUS is ready, will have the Port Power Role field set to Source. The Port Power Role field of a received Message Shall Not be verified by the receiver and Shall Not lead to Soft Reset, Hard Reset or Error Recovery if it is incorrect. The Port Power Role field Shall only be defined for SOP Packets. 6.2.1.1.5 Specification Revision The Specification Revision field Shall be one of the following values (except 11b):  00b - Revision 1.0 (Deprecated)  01b - Revision 2.0  10b - Revision 3.x  11b - Reserved, Shall Not be used. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every PD Specification Revision starting from [USB 2.0] for SOP*; the only exception to this is a VPD which Shall Ignore Messages sent with PD Specification Revision 2.0 and earlier. After a physical or logical (USB Type-C® Error Recovery) Attach, a Port discovers the common Specification Revision level between itself and its Port Partner and/or the Cable Plug(s), and uses this Specification Revision level until a Detach, Hard Reset or Error Recovery happens. After detection of the Specification Revision to be used, all PD communications Shall comply completely with the relevant Revision of the PD specification. The 2-bit Specification Revision field of a GoodCRC Message does not carry any meaning and Shall be considered as don't care by the recipient of the Message. The sender of a GoodCRC Message Shall set the Specification Revision field to 01b (Revision 2.0) when responding to a Message that contains 01b in the Specification Revision field of the Message Header. The sender of a GoodCRC Message May set the Specification Revision field to 01b or 10b when responding to a Message that contains 10b (Revision 3.x) in the Specification Revision field of the Message Header. The Specification Revision field Shall apply to all SOP* Packet types. An Attach event or a Hard Reset Shall cause the detection of the applicable Specification Revision to be performed for both Ports and Cable Plugs according to the rules stated below: When the Source Port first communicates with the Sink Port the Specification Revision field Shall be used as described by the following steps: 1) The Source Port sends a Source_Capabilities Message to the Sink Port setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Source Port supports. 2) The Sink Port responds with a Request Message setting the Specification Revision field to the highest Revision of the Power Delivery Specification the Sink Port supports that is equal to or lower than the Specification Revision received from the Source Port. 3) The Source and Sink Ports Shall use the Specification Revision in the Request Message from the Sink in step 2 in all subsequent communications until a Detach, Hard Reset, or Error Recovery happens. Prior to entering the First Explicit Contract, the VCONN Source Shall use the following steps to establish a Specification Revision level: 1) The VCONN Source sends a Discover Identity REQ to the Cable Plug (SOP’) setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports. After a VCONN Swap the required Soft_Reset / Accept Message exchange is used for the same purpose (see Section 6.3.13, "Soft Reset Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 119 2) The Cable Plug responds with a Discover Identity ACK setting the Specification Revision field in the Message to the highest Revision of the Power Delivery Specification the VCONN Source supports that is equal to or lower than the Specification Revision it received from the Source Port. 3) The Cable Plug and VCONN Source Shall communicate using the lower of the two revisions until an Explicit Contract has been established. 4) Table 6.2, "Revision Interoperability during an Explicit Contract" shows the Specification Revision that Shall be used between the Port Partners and the Cable Plugs when the Specification Revision has been discovered and an Explicit Contract is in place. Notes:  A VCONN Source that does not communicate with the Cable Plug(s) May skip the above procedure.  When a Cable Plug does not respond to a Revision 3.x Discover Identity REQ with a Discover Identity ACK or BUSY the VCONN Source May repeat steps 1-4 using a Revision 2.0 Discover Identity REQ in step 1 before establishing that there is no Cable Plug to communicate with. A VCONN Source that supports Revision 3.x of the Power Delivery Specification May communicate with a Cable Plug also supporting Revision 3.x using Revision 3.x Compliant Communications regardless of the Specification Revision of its Port Partner while no Explicit Contract exists. After an Explicit Contract has been established the Port Partners and Cable Plug(s) Shall use Table 6.2, "Revision Interoperability during an Explicit Contract" to determine the Revision to be used. All data in all Messages Shall be consistent with the Specification Revision field in the Message Header for that particular Message. A Cable Plug Shall Not save the state of the agreed Specification Revision. A Cable Plug Shall respond with the highest Specification Revision it supports that is equal to or lower than the Specification Revision contained in the Message received from the VCONN Source. Cable Plugs Shall operate using the same Specification Revision for both SOP’ and SOP’’. Cable assemblies with two Cable Plugs Shall operate using the same Specification Revision for both Cable Plugs. See Table 6.2, "Revision Interoperability during an Explicit Contract" for details of how various Revisions Shall inter-operate. 6.2.1.1.6 Port Data Role The 1-bit Port Data Role field Shall indicate the Port's present Data Role:  0b UFP  1b DFP Table 6.2 Revision Interoperability during an Explicit Contract Port 1 Revision Cable Plug Revision Port 2 Revision Port to Port Operating Revision Port to Cable Plug Operating Revision 2 2 2 2 2 2 2 3 2 2 2 3 2 2 2 2 3 3 2 2 3 2 2 2 2 3 2 3 3 2 3 3 2 2 2 3 3 3 3 3 Page 120 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Port Data Role field Shall only be defined for SOP Packets. For all other SOP* Packets the Port Data Role field is Reserved and Shall be set to zero. If a USB Type-C Port receives a Message with the Port Data Role field set to the same Data Role as its current Data Role, except for the GoodCRC Message, USB Type-C Error Recovery actions as defined in [USB Type-C 2.4] Shall be performed. For a USB Type-C Port the Port Data Role field Shall be set to the default value at Attachment after a Hard Reset: 0b for a Port with Rd asserted and 1b for a Port with Rp asserted. In the case that a Port is not USB Communications capable, at Attachment a Source Port Shall default to DFP and a Sink Port Shall default to UFP. 6.2.1.1.7 Cable Plug The 1-bit Cable Plug field Shall indicate whether this Message originated from a Cable Plug or VPD:  0b Message originated from a DFP or UFP.  1b Message originated from a Cable Plug or VPD The Cable Plug field Shall only apply to SOP’ Packet and SOP’’ Packet types. 6.2.1.1.8 Message Type The 5-bit Message Type field Shall indicate the type of Message being sent. To fully decode the Message Type, the Number of Data Objects field is first examined to determine whether the Message is a Control Message or a Data Message. Then the specific Message Type can be found in Table 6.5, "Control Message Types" or Table 6.6, "Data Message Types". The Message Type field Shall apply to all SOP* Packet types. 6.2.1.2 Extended Message Header Extended Messages (indicated by the Extended field being set in the Message Header) Shall contain an Extended Message Header following the Message Header as shown in Figure 6.3, "USB Power Delivery Packet Format including an Extended Message Header and Payload" and defined in “Table 6.3, "Extended Message Header". Extended Messages contain Data Blocks of Data Size, defined in the Extended Message, that are either sent in a single Message or as a series of Chunks. When the Data Block is sent as a series of Chunks, each Chunk in the series, except for the last Chunk, Shall contain MaxExtendedMsgChunkLen bytes. The last Chunk in the series Shall contain the remainder of the Data Block and so could be less than MaxExtendedMsgChunkLen bytes and Shall be padded to the next 4-byte Data Object boundary. 6.2.1.2.1 Chunked The Port Partners Shall use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine whether to send Messages of Data Size > MaxExtendedMsgLegacyLen bytes in a single Unchunked Extended Message (see Section 6.4.1.2.1.6, "Unchunked Extended Messages Supported" and Section 6.4.2.6, "Unchunked Extended Messages Supported"). Table 6.3 Extended Message Header Bit(s) Start of Packet Field Name Reference 15 SOP* Chunked Section 6.2.1.2.1 14…11 SOP* Chunk Number Section 6.2.1.2.2 10 SOP* Request Chunk Section 6.2.1.2.3 9 SOP* Reserved 8…0 SOP* Data Size Section 6.2.1.2.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 121 When either Port Partner only supports Chunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to one.  Every Extended Message of Data Size > MaxExtendedMsgLegacyLen Shall be transmitted between the Port Partners in Chunks  The Number of Data Objects in the Message Header Shall indicate the number of Data Objects in the Message padded to the 4-byte boundary including the Extended Message Header as part of the first Data Object. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When both Port Partners support Unchunked Extended Messages:  The Chunked bit in every Extended Message Shall be set to zero.  Every Extended Message Shall be transmitted between the Port Partners Unchunked.  The Number of Data Objects in the Message Header is Reserved. The conditions listed above Shall apply until the Port Pair is Detached, there is a Hard Reset, there is Error Recovery or the Source removes power (except during a Power Role Swap or Fast Role Swap when the Initial Source removes power in order to for the New Source to apply power). When sending Extended Messages to the Cable Plug the VCONN Source Shall only send Chunked Extended Messages. Cable Plugs Shall always send Extended Messages of Data Size > MaxExtendedMsgLegacyLen Chunked and Shall set the Chunked bit in every Extended Message to one. When Extended Messages are supported Chunking Shall be supported. 6.2.1.2.2 Chunk Number The Chunk Number field Shall only be Valid in a Message if the Chunked flag is set to one. If the Chunked flag is set to zero the Chunk Number field Shall also be set to zero. The Chunk Number field is used differently depending on whether the Message is a request for Data, or a requested Data Block being returned:  In a request for data the Chunk Number field indicates the number of the Chunk being requested. The requester Shall only set this field to the number of the next Chunk in the series (the next Chunk after the last received Chunk).  In the requested Data Block the Chunk Number field indicates the number of the Chunk being returned. The Chunk Number for each Chunk in the series Shall start at zero and Shall increment for each Chunk by one up to a maximum of 9 corresponding to 10 Chunks in total. 6.2.1.2.3 Request Chunk The Request Chunk bit Shall only be used for the Chunked transfer of an Extended Message when the Chunked bit is set to 1 (see Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)"). For Unchunked Extended Message transfers, Messages Shall be sent and received without the request/response mechanism (see Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)"). The Request Chunk bit Shall be set to one to indicate that this is a request for a Chunk of a Data Block and Shall be set to zero to indicate that this is a Chunk response containing a Chunk. Except for Chunk zero, a requested Chunk of a Data Block Shall only be returned as a Chunk response to a corresponding request for that Chunk. Both the Chunk request and the Chunk response Shall contain the same value in the Message Type field. When the Request Chunk bit is set to one the Data Size field Shall be zero. Page 122 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.2.1.2.4 Data Size The Data Size field Shall indicate how many bytes of data in total are in Data Block being returned. The total number of data bytes in the Message Shall Not exceed MaxExtendedMsgLen. If the Data Size field is less than MaxExtendedMsgLegacyLen and the Chunked bit is set then the Packet Payload Shall be padded to the next 4-byte Data Object boundary with zeros (0x00). If the Data Size field is greater than expected for a given Extended Message but less than or equal to MaxExtendedMsgLen then the expected fields in the Message Shall be processed appropriately and the additional fields Shall be Ignored. 6.2.1.2.5 Extended Message Examples The following examples illustrate the transmission of Extended Messages both Chunked (Chunked bit is one) and Unchunked (Chunked bit is zero). The examples use a Security_Request Message of Data Size 7 bytes which is responded to by a Security_Response Message of Data Size 30 bytes. The sizes of these Messages are arbitrary and are used to illustrate Message transmission; they are not intended to correspond to genuine security related Messages. During Negotiation of the Explicit Contract after connection, the Port Partners use the Unchunked Extended Messages Supported field in the Source_Capabilities Message and Unchunked Extended Messages Supported field in the Request Message to determine the value of the Chunked bit (see Table 6.4, "Use of Unchunked Message Supported bit"). When both Port Partners support Unchunked Extended Messages then the Chunked bit is zero otherwise the Chunked bit is one. The Chunked bit is used to determine whether:  The Chunk request/response mechanism is used.  Extended Messages are Chunked.  Padding is applied.  The Number of Data Objects field is used. The following examples illustrate the expected usage in each case. 6.2.1.2.5.1 Security_Request/Security_Response Unchunked Example Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Unchunked Extended Messages (Chunked bit is zero) between a USB Host and a Charger. The entire Data Block is returned in one Message. The Chunk request/response mechanism is not used. Table 6.4 Use of Unchunked Message Supported bit Source: Source_Capabilities Message Unchunked Message Supported bit = 0 Unchunked Message Supported bit = 1 Sink: Request Message Unchunked Message Supported bit = 0 Chunked bit = 1 Chunked bit = 1 Unchunked Message Supported bit = 1 Chunked bit = 1 Chunked bit = 0 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 123 Figure 6.4 Example Security_Request sequence Unchunked (Chunked bit = 0) Figure 6.5, "Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero)" details the Security_Request Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to 0, which in this case is 7 bytes. Figure 6.5 Example byte transmission for Security_Request Message of Data Size 7 (Chunked bit is set to zero) Figure 6.6, "Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero)" details the Security_Response Message shown in Figure 6.4, "Example Security_Request sequence Unchunked (Chunked bit = 0)". The figure shows the byte ordering on the bus as well as the fact that there is no padding in this case. The Number of Data Objects field has a value of 0 since it is Reserved when the Chunked bit is zero. The Data Size field indicates the length of the Extended Message when the Chunked bit is set to zero, which in this case is 30 bytes. Host Charger Security_Request (Data Size = 7, Chunked = 0) GoodCRC GoodCRC Security_Response (Data Size = 30, Chunked = 0) Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 0 (Reserved) Data (7 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 Page 124 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.6 Example byte transmission for Security_Response Message of Data Size 30 (Chunked bit is set to zero) 6.2.1.2.5.2 Security_Request/Security_Response Chunked Example Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" illustrates a typical sequence for a Security_Request Message responded to by a Security_Response Message using Chunked Extended Messages (Chunked bit is one) between a USB Host and a Charger. Note: Chunk Number zero in every Extended Message is sent without the need for a Chunk Request, but Chunk Number one and following need to be requested with a Chunk request. Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 0 (Reserved) Data (30 bytes) Extended Message Header (16 bit) Chunked = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B28 B29 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 125 Figure 6.7 Example Security_Request sequence Chunked (Chunked bit = 1) Figure 6.8, "Example Security_Request Message of Data Size 7 (Chunked bit set to 1)" shows the Security_Request Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Three bytes of padding have been added to the Message so that the total number of bytes is a multiple of 32-bits, corresponding to 3 Data Objects. The Number of Data Objects field is set to 3 to indicate the length of this Chunk. The Chunk Number is set to zero and the Data Size field is set to 7 to indicate the length of the whole Extended Message. Host Charger Security_Request (Number of Data Objects = 3, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 7) GoodCRC GoodCRC Security_Response (Number of Data Objects = 7, Chunked = 1, Chunk Number = 0, Request Chunk = 0, Data Size = 30) Security_Response “Chunk request” (Number of Data Objects = 1, Chunked = 1, Chunk Number = 1, Request Chunk = 1, Data Size = 0) GoodCRC GoodCRC Security_Response (Number of Data Objects = 2, Chunked = 1, Chunk Number = 1, Request Chunk = 0, Data Size = 30) Security_Request Chunk Security_Response Page 126 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.8 Example Security_Request Message of Data Size 7 (Chunked bit set to 1) Figure 6.9, "Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number zero of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. No padding is need for this Chunk since the full 26-byte Payload plus 2-byte Extended Message Header is a multiple of 32-bits, corresponding to 7 Data Objects. The Number of Data Objects field is set to 7 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.9 Example Chunk 0 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" shows an example of the Message format, byte ordering and padding for the Security_Response Message Chunk request for Chunk Number one shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)". In the Chunk request the Number of Data Objects field in the Message is set to 1 to indicate that the Payload is 32 bits equivalent to 1 data object (see Figure 6.10, "Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1)"). Since the Chunked bit is set to 1 the Chunk request/Chunk response mechanism is used. The Message is a Chunk request so the Request Chunk bit is set to one, and in this case Chunk one is being requested so Chunk Number is set to one. Data Size is set to zero indicating the length of the Data Block being transferred. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits. Message Header (16 bit) Message Type = Security_Request Number of Data Objects = 3 Data (7 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 7 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 B4 B5 B6 P0 (0x00) P1 (0x00) P2 (0x00) Padding (3 bytes) Data Object 0 Data Object 1 Data Object 2 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 7 Data (26 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 0 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B22 B23 Data Object 0 B24 B25 Data Object 6 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 127 Figure 6.10 Example byte transmission for a Security_Response Message Chunk request (Chunked bit is set to 1) Figure 6.11, "Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1)" shows Chunk Number one of the Security_Response Message shown in Figure 6.7, "Example Security_Request sequence Chunked (Chunked bit = 1)" in more detail including the byte ordering on the bus and padding. Two bytes of padding are added to ensure that the Payload is a multiple of 32 bits, corresponding to 2 Data Objects. The Number of Data Objects field is set to 2 to indicate the length of this Chunk and the Data Size field is set to 30 to indicate the length of the whole Extended Message. Figure 6.11 Example Chunk 1 of Security_Response Message of Data Size 30 (Chunked bit set to 1) Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 1 Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 1 Data Size = 0 Message Header LSB Message Header MSB Message Header LSB Message Header MSB P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Message Header (16 bit) Message Type = Security_Response Number of Data Objects = 2 Data (4 bytes) Extended Message Header (16 bit) Chunked = 1 Chunk Number = 1 Request Chunk = 0 Data Size = 30 Message Header LSB Message Header MSB Message Header LSB Message Header MSB B0 B1 B2 B3 P0 (0x00) P1 (0x00) Padding (2 bytes) Data Object 0 Data Object 1 Page 128 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3 Control Message A Message is defined as a Control Message when the Number of Data Objects field in the Message Header is set to zero. The Control Message consists only of a Message Header and a CRC. The Protocol Layer originates the Control Messages (i.e., Accept Message, Reject Message etc.). The Control Message types are specified in the Message Header's Message Type field (bits 4…0) and are summarized in Table 6.5, "Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.5 Control Message Types Bits 4…0 Message Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 0_0001 GoodCRC Source, Sink or Cable Plug See Section 6.3.1. SOP* 0_0010 GotoMin (Deprecated) Deprecated See Section 6.3.2. N/A 0_0011 Accept Source, Sink or Cable Plug See Section 6.3.3. SOP* 0_0100 Reject Source, Sink or Cable Plug See Section 6.3.4. SOP* 0_0101 Ping (Deprecated) Deprecated See Section 6.3.5. SOP only 0_0110 PS_RDY Source or Sink See Section 6.3.6. SOP only 0_0111 Get_Source_Cap Sink or DRP See Section 6.3.7. SOP only 0_1000 Get_Sink_Cap Source or DRP See Section 6.3.8. SOP only 0_1001 DR_Swap Source or Sink See Section 6.3.9. SOP only 0_1010 PR_Swap Source or Sink See Section 6.3.10. SOP only 0_1011 VCONN_Swap Source or Sink See Section 6.3.11. SOP only 0_1100 Wait Source or Sink See Section 6.3.12. SOP only 0_1101 Soft_Reset Source or Sink See Section 6.3.13. SOP* 0_1110 Data_Reset Source or Sink See Section 6.3.14. SOP only 0_1111 Data_Reset_Complete Source or Sink See Section 6.3.15. SOP only 1_0000 Not_Supported Source, Sink or Cable Plug See Section 6.3.16. SOP* 1_0001 Get_Source_Cap_Extended Sink or DRP See Section 6.3.17. SOP only 1_0010 Get_Status Source or Sink See Section 6.3.18. SOP* 1_0011 FR_Swap Sink1 See Section 6.3.19. SOP only 1_0100 Get_PPS_Status Sink See Section 6.3.20. SOP only 1_0101 Get_Country_Codes Source or Sink See Section 6.3.21. SOP only 1_0110 Get_Sink_Cap_Extended Source or DRP See Section 6.3.22. SOP only 1_0111 Get_Source_Info Sink or DRP See Section 6.3.23. SOP Only 1_1000 Get_Revision Source or Sink See Section 6.3.24. SOP* 1_1001… 1_1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. 1) In this case the Port is providing vSafe5V however it will have Rd asserted rather than Rp and sets the Port Power Role field to Sink, until the Fast Role Swap AMS has completed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 129 6.3.1 GoodCRC Message The GoodCRC Message Shall be sent by the receiver to acknowledge that the previous Message was correctly received (i.e., had a GoodCRC Message). The GoodCRC Message Shall return the Message's MessageID so the sender can determine that the correct Message is being acknowledged. The first bit of the GoodCRC Message Shall be returned within tTransmit after receipt of the last bit of the previous Message. BIST does not send the GoodCRC Message while in a Continuous BIST Mode (see Section 6.4.3, "BIST Message"). The retry mechanism is triggered when the Message sender fails to receive a GoodCRC Message before the CRCReceiveTimer expires. It is used by the Message sender to detect that the Message was not correctly received by the Message recipient due to noise or other disturbance on the Configuration Channel (CC). The retry mechanism Shall Not be used for any other purpose such as a means of gaining time for processing the required response to the received Message. 6.3.2 GotoMin Message (Deprecated) The GotoMin (Deprecated) Message has been Deprecated. The 0_0010 Message Type is no longer Valid and Shall be responded to by a Not_Supported Message. 6.3.3 Accept Message The Accept Message is a Valid response in the following cases:  It Shall be sent by the Source, in SPR Mode, to signal the Sink that the Source is willing to meet the Request Message.  It Shall be sent by the Source, in EPR Mode, to signal the Sink that the Source is willing to meet the EPR_Request Message.  It Shall be sent by the recipient of the PR_Swap Message to signal that it is willing to do a Power Role Swap and has begun the Power Role Swap AMS.  It Shall be sent by the recipient of the DR_Swap Message to signal that it is willing to do a Data Role Swap and has begun the Data Role Swap AMS.  It Shall be sent by the recipient of the VCONN_Swap Message to signal that it is willing to do a VCONN Swap and has begun the VCONN Swap AMS.  It Shall be sent by the recipient of the FR_Swap Message to indicate that it has begun the Fast Role Swap AMS.  It Shall be sent by the recipient of the Soft_Reset Message to indicate that it has completed its Soft Reset.  It Shall be sent by the recipient of the Enter_USB Message to indicate that it has begun the Enter USB AMS.  It Shall be sent by the recipient of the Data_Reset Message to indicate that it has begun the Data Reset AMS. The Accept Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.6.2, "SenderResponseTimer"). 6.3.4 Reject Message The Reject Message is a Valid response in the following cases:  It Shall be sent to signal the Sink, in SPR Mode, that the Source is unable to meet the Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised. Page 130 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  It Shall be sent to signal the Sink, in EPR Mode, that the Source is unable to meet the EPR_Request Message. This May be due an Invalid request or because the Source can no longer provide what it previously Advertised.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is unable to do a Power Role Swap.  It Shall be sent by the recipient of a PR_Swap Message while in EPR Mode.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source, to indicate it is unable to do a VCONN Swap.  It Shall be sent by UFP on receiving an Enter_USB Message to indicate it is unable to enter the requested USB Mode. The sender of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message, on receiving a Reject Message response, Shall Not send this same Message to the recipient until one of the following has occurred:  A New Explicit Contract Negotiation as a result of the Source sending a Source_Capabilities Message or EPR_Source_Capabilities Message. This can be triggered by:  The Source's Device Policy Manager.  A Get_Source_Cap Message sent from the Sink to the Source in SPR Mode.  An EPR_Get_Source_Cap Message sent from the Sink to the Source in EPR Mode.  A Power Role Swap.  A Soft Reset.  A Hard Reset.  A Disconnect/Re-connect.  A Data Role Swap.  A Data Reset. The Sink May send a different Request Message to the one which was rejected but Shall Not repeat the same Request Message, using the same RDO, unless there has been a New Explicit Contract Negotiation, Data Role Swap or Data Reset as described above. The Reject Message Shall be sent within tReceiverResponse of the receipt of the last bit of Message (see Section 6.6.2, "SenderResponseTimer"). Note: The Reject Message is not a Valid response when a Message is not supported. In this case the Not_Supported Message is returned (see Section 6.3.16, "Not_Supported Message"). 6.3.5 Ping Message The Ping (Deprecated) Message has been deprecated. The 0_0101 Message Type is no longer Valid. A Port that receives a Ping (Deprecated) Message May respond with a Not_Supported Message or Ignore the Ping (Deprecated) Message. A Cable Plug that receives a Ping (Deprecated) Message Shall Ignore the Ping (Deprecated) Message. 6.3.6 PS_RDY Message The PS_RDY Message Shall be sent by the Source (or by both the New Sink and New Source during the Power Role Swap AMS or Fast Role Swap AMS) to indicate its power supply has reached the desired operating condition (see Section 8.3.2.2, "Power Negotiation"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 131 6.3.7 Get_Source_Cap Message The Get_Source_Cap (Get Source Capabilities) Message May be sent by a Port to request the Source Capabilities and Dual-Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message"). 6.3.8 Get_Sink_Cap Message The Get_Sink_Cap (Get Sink Capabilities) Message May be sent by a Port to request the Sink Capabilities and Dual- Role Power capability of its Port Partner (e.g., Dual-Role Power capable). The Port Shall respond by returning a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message"). 6.3.9 DR_Swap Message The DR_Swap Message is used to exchange DFP and UFP operation between Port Partners while maintaining the direction of power flow over VBUS. The Data Role Swap process can be used by Port Partners whether or not they support USB Communications capability. A DFP that supports USB Communication capability starts as the USB Host on Attachment. A UFP that supports USB Communication capability starts as the USB Device on Attachment. [USB Type-C 2.4] Dual-Role Data (DRD) Ports Shall have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. DFPs and UFPs May have the capability to perform a Data Role Swap from the PE_SRC_Ready or PE_SNK_Ready states. A Data Role Swap Shall be regarded in the same way as a cable Detach/ Re-attach in relation to any USB Communication which is ongoing between the Port Partners. If there are any Active Modes between the Port Partners when a DR_Swap Message is a received, then a Hard Reset Shall be performed (see Section 6.4.4.3.4, "Enter Mode Command"). If the Cable Plug has any Active Modes then the DFP Shall Not issue a DR_Swap Message and Shall cause all Active Modes in the Cable Plug to be exited before accepting a Data Role Swap request. The source of VBUS and VCONN Source Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the Data Role Swap process. The DR_Swap Message May be sent by either Port Partner. The recipient of the DR_Swap Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait").  If an Accept Message is sent, the Source and Sink Shall exchange Data Roles.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Data Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Data Role Swap might be possible in the future but that no immediate action Shall be taken. Before a Data Role Swap the initial DFP Shall have its Port Data Role bit set to DFP, and the initial UFP Shall have its Port Data Role bit set to UFP. After a successful Data Role Swap the DFP/Host Shall become the UFP/Device and vice-versa; the new DFP Shall have its Port Data Role bit set to DFP, and the new UFP Shall have its Port Data Role bit set to UFP. Where USB Communication is supported by both Port Partners a USB data connection Should be established according to the new Data Roles. If the Data Role Swap, after having been accepted by the Port Partner, is subsequently not successful, in order to attempt a re-establishment of the connection, USB Type-C Error Recovery actions, such as disconnect, as defined in [USB Type-C 2.4] will be necessary. See Section 8.3.2.9, "Data Role Swap". 6.3.10 PR_Swap Message The PR_Swap Message May be sent by either Port Partner to request an exchange of Power Roles. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). Page 132 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If an Accept Message is sent, the Source and Sink Shall do a Power Role Swap.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a Power Role Swap and no action Shall be taken.  If a Wait Message is sent, the requester is informed that a Power Role Swap might be possible in the future but that no immediate action Shall be taken. The PR_Swap Message Shall Not be sent while in EPR Mode. While in EPR Mode if a Power Role Swap is required, an EPR Mode exit Shall be done first. After a successful Power Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the New Source Shall also reset its CapsCounter. The New Source Shall have Rp asserted on the CC wire and the New Sink Shall have Rd asserted on the CC wire as defined in [USB Type-C 2.4]. When performing a Power Role Swap from Source to Sink, the Port Shall change its CC wire resistor from Rp to Rd. When performing a Power Role Swap from Sink to Source, the Port Shall change its CC wire resistor from Rd to Rp. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged by the Power Role Swap process. Note: During the Power Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Power Role Swap, refer to:  Section 7.3.2, "Transitions Caused by Power Role Swap"  Section 8.3.2.5, "Data Reset".  Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram".  Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram".  Section 9.1.2, "Mapping to USB Device States". 6.3.11 VCONN_Swap Message The VCONN_Swap Message Shall be supported by any Port that can operate as a VCONN Source. The VCONN_Swap Message May be sent by either Port Partner to request an exchange of VCONN Source. The recipient of the Message Shall respond by sending an Accept Message, Reject Message, Wait Message (see Section 6.9, "Accept, Reject and Wait") or Not_Supported Message.  If an Accept Message is sent, the Port Partners Shall perform a VCONN Swap. The new VCONN Source Shall send a PS_RDY Message within tVcONNSourceOn to indicate that it is now sourcing VCONN. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of receipt of the last bit of the EOP of the PS_RDY Message.  If a Reject Message is sent, the requester is informed that the recipient is unable, or unwilling, to do a VCONN Swap and no action Shall be taken. A Reject Message Shall only be sent by the Port that is not presently the VCONN Source in response to a VCONN_Swap Message. The Port that is presently the VCONN Source Shall Not send a Reject Message in response to VCONN_Swap Message.  If a Wait Message is sent, the requester is informed that a VCONN Swap might be possible in the future but that no immediate action Shall be taken. A Port after losing the VCONN Source role due to incoming VCONN Swap request Shall Not initiate a VCONN Swap until at least tVCONNSwapDelayDFP/ tVCONNSwapDelayUFP after completing the previous VCONN Swap AMS.  If a Not_Supported Message is sent, the requester is informed that VCONN Swap is not supported. The Port that is not presently the VCONN Source May turn on VCONN when a Not_Supported Message is received in response to a VCONN_Swap Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 133 The DFP (Host), UFP (Device) Data Roles and Source of VBUS Shall remain unchanged as well as the Rp/Rd resistors on the CC wire during the VCONN Swap process. VCONN Shall be continually sourced during the VCONN Swap process to maintain power to the Cable Plug(s) i.e., make before break. Before communicating with a Cable Plug a Port Shall ensure that it is the VCONN Source and that the Cable Plugs are powered, by performing a VCONN Swap if necessary. Since it cannot be guaranteed that the present VCONN Source is supplying VCONN, the only means to ensure that the Cable Plugs are powered is for a Port wishing to communicate with a Cable Plug to become the VCONN Source. If a Not_Supported Message is returned in response to the VCONN_Swap Message, then the Port is allowed to become the VCONN Source until a Hard Reset or Detach. A VCONN Source that is also a Source can attempt to send a Discover Identity Command using SOP’ to a Cable Plug prior to the establishment of the First Explicit Contract. Note: Even when it is presently the VCONN Source, the Sink is not permitted to initiate an AMS with a Cable Plug unless Rp is set to SinkTxOK (see Section 6.9, "Accept, Reject and Wait"). 6.3.12 Wait Message The Wait Message is a Valid response to one of the following Messages:  It Shall be sent to signal the Sink, in response to a Request Message in SPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent to signal the Sink, in response to a EPR_Request Message in EPR Mode during Negotiation, to indicate that the Source is currently unable to meet the request.  It Shall be sent by the recipient of a PR_Swap Message to indicate it is currently unable to do a Power Role Swap.  It Shall be sent by the recipient of a DR_Swap Message to indicate it is currently unable to do a Data Role Swap.  It Shall be sent by the recipient of a VCONN_Swap Message that is not presently the VCONN Source to indicate it is currently unable to do a VCONN Swap.  It Shall be sent by the recipient of an Enter_USB Message to indicate it is currently unable to enter the requested USB Mode. The Wait Message Shall be sent within tReceiverResponse of the receipt of the last bit of the Message (see Section 6.9, "Accept, Reject and Wait"). 6.3.12.1 Wait in response to a Request Message The Wait Message allows the Source time to recover the power it requires to meet the request, e.g., through Re- negotiation with other Sinks or an upstream Source. A Source Should only send a Wait Message in response to a Request Message when an Explicit Contract exists between the Port Partners. The Sink is allowed to repeat the Request Message using the SinkRequestTimer and Shall ensure that there is tSinkRequest after receiving the Wait Message before sending another Request Message. 6.3.12.2 Wait in response to a PR_Swap Message The Wait Message is used when responding to a PR_Swap Message to indicate that a Power Role Swap might be possible in the future. This can occur in any case where the device receiving the PR_Swap Message needs to evaluate the request further e.g., by requesting Sink Capabilities from the originator of the PR_Swap Message. Once it has completed this evaluation one of the Port Partners Should initiate the Power Role Swap process again by sending a PR_Swap Message. The Wait Message is also used where a Hub is operating in hybrid mode when a request cannot be satisfied (see [UCSI]). Page 134 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A Port that receives a Wait Message in response to a PR_Swap Message Shall wait tPRSwapWait after receiving the Wait Message before sending another PR_Swap Message. 6.3.12.3 Wait in response to a DR_Swap Message The Wait Message is used when responding to a DR_Swap Message to indicate that a Data Role Swap might be possible in the future. This can occur in any case where the device receiving the DR_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the Data Role Swap process again by sending a DR_Swap Message. A Port that receives a Wait Message in response to a DR_Swap Message Shall wait tDRSwapWait after receiving the Wait Message before sending another DR_Swap Message. 6.3.12.4 Wait in response to a VCONN_Swap Message The Wait Message is used when responding to a VCONN_Swap Message to indicate that a VCONN_Swap might be possible in the future. This can occur in any case where the device receiving the VCONN_Swap Message needs to evaluate the request further. Once it has completed this evaluation one of the Port Partners Should initiate the VCONN Swap process again by sending a VCONN_Swap Message. A Port that receives a Wait Message in response to a VCONN_Swap Message Shall wait tVCONNSwapWait after receiving the Wait Message before sending another VCONN_Swap Message. A Port that is currently the VCONN Source Shall respond with an Accept Message (rather than a Wait Message) if the Port Partner's Revision and Version, as reported in the Revision Message, is earlier than R3.2 V1.1. A Port Partner supporting an earlier Revision and Version will not expect a Wait Message and will generate a Soft Reset in response. 6.3.12.5 Wait in response to an Enter_USB Message The Wait Message is used, by the UFP, when responding to an Enter_USB Message to indicate that entering the requested USB Mode might be possible in the future. This can occur, for example, in any case where the UFP needs to Negotiate more power to enter the mode. Once the UFP has completed this the DFP Should initiate the Enter USB process again by sending an Enter_USB Message. A DFP that receives a Wait Message in response to an Enter_USB Message Shall wait tEnterUSBWait after receiving the Wait Message before sending another Enter_USB Message. 6.3.13 Soft Reset Message A Soft_Reset Message May be initiated by either the Source or Sink to its Port Partner requesting a Soft Reset. The Soft_Reset Message Shall cause a Soft Reset of the connected Port Pair (see Section 6.8.1, "Soft Reset and Protocol Error"). If the Soft_Reset Message fails a Hard Reset Shall be initiated within tHardReset of the last CRCReceiveTimer expiring after nRetryCount retries have been completed. A Soft_Reset Message is used to recover from Protocol Layer errors; putting the Message counters to a known state to regain Message synchronization. The Soft_Reset Message has no effect on the Source or Sink; that is the previously Negotiated direction. Voltage and current remain unchanged. Modal Operation is unaffected by Soft Reset. However after a Soft Reset has completed, an Explicit Contract Negotiation occurs, in order to re-establish PD Communication and to bring state operation for both Port Partners back to either the PE_SNK_Ready or PE_SRC_Ready states as appropriate (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams"). A Soft_Reset Message May be sent by either the Source or Sink when there is a Message synchronization error. If the error is not corrected by the Soft Reset, Hard Reset Signaling Shall be issued (see Section 6.8.3, "Hard Reset"). A Soft_Reset Message Shall be targeted at a specific entity depending on the type of SOP* Packet used. Soft_Reset Messages sent using SOP Packets Shall Soft Reset the Port Partner only. Soft_Reset Messages sent using SOP’ Packet/ SOP’’ Packets Shall Soft Reset the corresponding Cable Plug only. After a VCONN Swap the VCONN Source needs to reset the Cable Plug's Protocol Layer to ensure MessageID synchronization. If after a VCONN Swap the VCONN Source wants to communicate with a Cable Plug using SOP’ Packets, it Shall issue a Soft_Reset Message using a SOP’ Packet in order to reset the Cable Plug's Protocol Layer. If Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 135 the VCONN Source wants to communicate with a Cable Plug using SOP’’ Packets, it Shall issue a Soft_Reset Message using a SOP’’ Packet in order to reset the Cable Plug's Protocol Layer. 6.3.14 Data_Reset Message The Data_Reset Message May be sent by either the DFP or UFP and Shall reset the USB data connection and exit all Alternate Modes with its Port Partner while preserving the power on VBUS. USB4® Mode capable ports Shall support the Data_Reset Message and other ports May support the Data_Reset Message. The Data_Reset Message Shall Not change the existing:  Power Contract  Data Roles (i.e., which Port is the DFP or UFP) The receiver of the Data_Reset Message Shall respond by sending an Accept Message and then follow the process outlined in the following steps. Neither the sender nor receiver Shall initiate a VCONN Swap until the Data Reset process is complete, and the Data_Reset_Complete Message has been sent. Following receipt of the Accept Message, or GoodCRC following the Accept, depending which Port sends the Data_Reset Message: 1) The DFP Shall:  Disconnect the Port's [USB 2.0] D+/D- signals.  If operating in [USB 3.2] remove the Port's Rx Terminations (see [USB 3.2]).  If operating in [USB4] drive the Port's SBTX to a logic low (see [USB4]). 2) Both the DFP and UFP Shall exit all Alternate Modes if any. 3) Reset the cable:  If the VCONN Source Port is also the UFP, then it Shall run the UFP VCONN Power Cycle process de- scribed in Section 7.1.15.1, "UFP VCONN Power Cycle".  If the VCONN Source Port is also the DFP, then it Shall run the DFP VCONN Power Cycle process de- scribed in Section 7.1.15.2, "DFP VCONN Power Cycle".  The DFP Shall exit the VCONN Power Cycle process as the VCONN Source and be sourcing VCONN. 4) After tDataReset the DFP Shall:  Reconnect the [USB 2.0] D+/D- signals.  If the Port was operating in [USB 3.2] or [USB4] reapply the Port's Rx Terminations (see [USB 3.2]). 5) The Data Reset process is complete; the DFP Shall send a Data_Reset_Complete Message and enter the USB4® Discovery and Entry Flow (See [USB Type-C 2.4]). If the Initiator of the Data_Reset Message does not receive a Valid response within tSenderResponse it Shall enter the ErrorRecovery State. 6.3.15 Data_Reset_Complete Message The Data_Reset_Complete Message Shall be sent by the DFP to the UFP to indicate the completion of the Data Reset process (see Section 6.3.14, "Data_Reset Message"). 6.3.16 Not_Supported Message The Not_Supported Message Shall be sent by a Port or Cable Plug in response to any Message it does not support. Returning a Not_Supported Message is assumed in this specification and has not been called out explicitly except in Section 6.13, "Message Applicability" which defines cases where the Not_Supported Message is returned. Page 136 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.3.17 Get_Source_Cap_Extended Message The Get_Source_Cap_Extended Message is sent by a Port to request additional information about a Port's Source Capabilities. The Port Shall respond by returning a Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message"). 6.3.18 Get_Status Message The Get_Status Message is sent by a Port using SOP to request the Port Partner's present status. The Port Partner Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). A Port that receives an Alert Message (see Section 6.4.6, "Alert Message") indicates that the Source or Sink's Status has changed and Should be re-read using a Get_Status Message. The Get_Status Message May also be sent to an Active Cable to get its present status using SOP’/SOP’’. The Active Cable Shall respond by returning a Status Message (see Section 6.5.2, "Status Message"). 6.3.19 FR_Swap Message The FR_Swap Message Shall be sent by the New Source within tFRSwapInit after it has detected a Fast Role Swap signal (see Section 5.8.6.3, "Fast Role Swap Detection" and Section 6.6.17.3, "tFRSwapInit"). The Fast Role Swap AMS is necessary to apply Rp to the New Source and Rd to the New Sink and to re-synchronize the state machines. The tFRSwapInit time Shall be measured from the time the Fast Role Swap Request has been sent for tFRSwapRx (max) until the last bit of the EOP of the FR_Swap Message has been transmitted by the PHY Layer. The recipient of the FR_Swap Message Shall respond by sending an Accept Message. After a successful Fast Role Swap the Port Partners Shall reset their respective Protocol Layers (equivalent to a Soft Reset): resetting their MessageIDCounter, RetryCounter and Protocol Layer state machines before attempting to establish the First Explicit Contract. At this point the Source Shall also reset its CapsCounter. This ensures that only the Cable Plug responds with a GoodCRC Message to the Discover Identity Command. Prior to the Fast Role Swap AMS, the New Source Shall have Rd asserted on the CC wire and the New Sink Shall have Rp asserted on the CC wire. Note: This is an incorrect assignment of Rp/Rd (since Rp follows the Source and Rd follows the Sink as defined in [USB Type-C 2.4]) that is corrected by the Fast Role Swap AMS. During the Fast Role Swap AMS, the New Source Shall change its CC wire resistor from Rd to Rp and the New Sink Shall change its CC wire resistor from Rp to Rd. The DFP (Host), UFP (Device) Data Roles and VCONN Source Shall remain unchanged during the Fast Role Swap process. The Initial Source Should avoid being the VCONN Source (by using the VCONN Swap process) whenever not actively communicating with the cable, since it is difficult for the Initial Source to maintain VCONN power during the Fast Role Swap process. Note: A Fast Role Swap is a "best effort" solution to a situation where a PDUSB Device has lost its external power. This process can occur at any time, even during an AMS in which case error handling such as Hard Reset or [USB Type-C 2.4] Error Recovery will be triggered. Note: During the Fast Role Swap process the Initial Sink does not disconnect even though VBUS drops below vSafe5V. For more information regarding the Fast Role Swap process, refer to:  Section 7.1.13, "Fast Role Swap"  Section 7.2.10, "Fast Role Swap"  Section 8.3.3.19.5, "Policy Engine in Source to Sink Fast Role Swap State Diagram"  Section 8.3.3.19.6, "Policy Engine in Sink to Source Fast Role Swap State Diagram" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 137  Section 9.1.2, "Mapping to USB Device States" for VBUS mapping to USB states. 6.3.20 Get_PPS_Status The Get_PPS_Status Message is sent by the Sink to request additional information about a Source's status. The Port Shall respond by returning a PPS_Status Message (see Section 6.5.10, "PPS_Status Message"). 6.3.21 Get_Country_Codes The Get_Country_Codes Message is sent by a Port to request the alpha-2 country codes its Port Partner supports as defined in [ISO 3166]. The Port Partner Shall respond by returning a Country_Codes Message (see Section 6.5.11, "Country_Codes Message"). 6.3.22 Get_Sink_Cap_Extended Message The Get_Sink_Cap_Extended (Get Sink Capabilities Extended) Message is sent by a Port to request additional information about a Port's Sink Capabilities. The Port Shall respond by returning a Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). 6.3.23 Get_Source_Info Message The Get_Source_Info Message is sent by a Port to request the type, maximum Capabilities and present Capabilities of the Port when it is operating as a Source. The Port Shall respond by returning the Source_Info Message (See Section 6.4.11, "Source_Info Message"). 6.3.24 Get_Revision Message The Get_Revision Message is sent by a Port using SOP to request the Revision and Version of the Power Delivery Specification its Port Partner supports. The Port Partner Shall respond by returning a Revision Message (See Section 6.4.12, "Revision Message"). The Get_Revision Message May also be sent to a Cable Plug to request the Revision and Version of the Power Delivery Specification it supports using SOP’/SOP’’. The Active Cable Shall respond by returning a Revision Message (see Section 6.4.12, "Revision Message"). Page 138 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4 Data Message A Data Message Shall consist of a Message Header and be followed by one or more Data Objects. Data Messages are easily identifiable because the Number of Data Objects field in the Message Header is a non-zero value. There are many types of Data Objects used to compose Data Messages. Some examples are:  Power Data Object (PDO) used to expose a Source Port's power Capabilities or a Sink's power requirements.  Request Data Object (RDO) used by a Sink Port to Negotiate an Explicit Contract.  Vendor Data Object (VDO) used to convey vendor specific information.  BIST Data Object (BDO) used for PHY Layer compliance testing.  Battery Status Data Object (BSDO) used to convey Battery status information.  Alert Data Object (ADO) used to indicate events occurring on the Source or Sink. The type of Data Object being used in a Data Message is defined by the Message Header's Message Type field and is summarized in Table 6.6, "Data Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.6 Data Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0_0000 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0_0001 Source_Capabilities Source or Dual-Role Power See Section 6.4.1.5 SOP only 0_0010 Request Sink only See Section 6.4.2 SOP only 0_0011 BIST Tester, Source or Sink See Section 6.4.3 SOP* 0_0100 Sink_Capabilities Sink or Dual-Role Power See Section 6.4.2 SOP only 0_0101 Battery_Status Source or Sink See Section 6.4.5 SOP only 0_0110 Alert Source or Sink See Section 6.4.6 SOP only 0_0111 Get_Country_Info Source or Sink See Section 6.4.7 SOP only 0_1000 Enter_USB DFP See Section 6.4.8 SOP* 0_1001 EPR_Request Sink See Section 6.4.9 SOP only 0_1010 EPR_Mode Source or Sink See Section 6.4.10 SOP only 0_1011 Source_Info Source See Section 6.4.11 SOP only 0_1100 Revision Source, Sink or Cable Plug See Section 6.4.12 SOP* 0_1101…0 _1110 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A 0 1111 Vendor_Defined Source, Sink or Cable Plug See Section 6.4.4 SOP* 1_0000…1 _1111 Reserved N/A All values not explicitly defined are Reserved and Shall Not be used. N/A Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 139 6.4.1 Capabilities Message There are two distinct Capabilities Messages: one used while in SPR Mode and another while in EPR Mode. This section defines the Capabilities Messages specific to the SPR Mode and Section 6.5.15, "EPR Capabilities Message" defines the Capabilities Messages specific to the EPR Mode. 6.4.1.1 Power Data Objects Sections Section 6.4.1.5, "SPR Source Capabilities Message" and Section 7.1.3, "Types of Sources" describes the Power Data Objects (PDOs) used in the construction of a Capabilities Message for both SPR Mode and EPR Mode. There are three types of Power Data Objects. They contain additional information beyond that encoded in the Message Header to identify each of the three types of Power Data Objects:  Fixed Supply is used to expose well-regulated fixed voltage power supplies.  Variable Supply is used to expose very poorly regulated power supplies.  Battery Supply is used to expose batteries that can be directly connected to VBUS. There are three types of Augmented Power Data Objects:  SPR PPS is used to expose a power supply whose output voltage can be programmatically adjusted over the Advertised voltage range and limited by the Source to a programmable current limit.  SPR AVS and EPR AVS are used to expose a power supply whose output voltage can be adjusted over the Advertised voltage range but otherwise is equivalent to a Fixed Supply (AVS does not support a programmable current limit). Power Data Objects are also used to expose additional Capabilities that May be utilized, such as in the case of a Power Role Swap. A list of one or more Power Data Objects Shall be sent by the Source to convey its Capabilities. The Sink May then request one of these Capabilities by returning a Request Data Object that contains an index to a Power Data Object, to Negotiate a mutually agreeable Explicit Contract. Where Maximum and Minimum voltage and current values are given in PDOs these Shall be taken to be absolute values. The Source and Sink Shall Not Negotiate a power level that would allow the current to exceed the maximum current supported by their receptacles or the Attached plug (see [USB Type-C 2.4]). The Source Shall limit its offered Capabilities to the maximum current supported by its receptacle and Attached plug. A Sink Shall only make a request from any of the Capabilities offered by the Source. For further details see Section 4.4, "Cable Type Detection". Sources expose their power Capabilities by sending a Source_Capabilities Message. Sinks expose their power requirements by sending a Sink_Capabilities Message. Both are composed of several 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). Table 6.7 Power Data Object Bit(s) Description Value Parameter B31…30 00b Fixed Supply (Vmin = Vmax) 01b Battery 10b Variable Supply (non-Battery) 11b Augmented Power Data Object (APDO) B29…0 Specific Power Capabilities are described by the PDOs in the following sections. Page 140 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Augmented Power Data Object (APDO) is defined to allow support for more than the four PDO types by extending the Power Data Object field from 2 to 4 bits when the B31…B30 are 11b. The generic APDO structure is shown in Table 6.8, "Augmented Power Data Object". Table 6.8 Augmented Power Data Object Bit(s) Description Value Parameter B31…30 11b Augmented Power Data Object (APDO) B29…28 00b SPR PPS 01b EPR AVS 10b SPR AVS 11b Reserved B27…0 Specific Power Capabilities are described by the APDOs in the following sections. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 141 6.4.1.2 Source Power Data Objects This section lists the types of PDOs a Source can use in an SPR Capabilities or EPR Capabilities Message. 6.4.1.2.1 Fixed Supply Power Data Object Table 6.9, "Fixed Supply PDO – Source" describes the Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources"for the electrical requirements of the power supply. Since all USB Providers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29…23. All other Fixed Supply Power Data Objects Shall set bits 29…23 to zero. For a Source offering no Capabilities, the Voltage field (B19…10) Shall be set to 5V and theMaximum Current field Shall be set to 0mA. This is used in cases such as a Dual-Role Power device which offers no Capabilities in its default Power Role or when external power is required to offer power. When a Source wants a Sink, consuming power from VBUS, to go to its lowest power state, the Voltage field (B19…10) Shall be set to 5V and the Maximum Current field Shall be set to 0mA. This is used in cases where the Source wants the Sink to draw pSnkSusp. 6.4.1.2.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.2 USB Suspend Supported Prior to an Explicit Contract or when the USB Communications Capable bit is set to zero, the USB Suspend Supported flag is undefined and Sinks Shall follow the rules for suspend as defined in [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. After an Explicit Contract has been Negotiated:  If the USB Suspend Supported flag is set, then the Sink Shall follow the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and resume. A PDUSB Peripheral May draw up to pSnkSusp during suspend; a PDUSB Hub May draw up to pHubSusp during suspend (see Section 7.2.3, "Sink Standby"). Table 6.9 Fixed Supply PDO – Source Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ for Dual-Role Power device. B28 USB Suspend Supported Set to ‘1’ if USB suspend is supported. B27 Unconstrained Power Set to ‘1’ if unconstrained power is available. B26 USB Communications Capable Set to ‘1’ if capable of USB Communications capable B25 Dual-Role Data Set to ‘1’ for a Dual-Role Data device. B24 Unchunked Extended Messages Supported Set to ‘1 if Unchunked Extended Messages are supported. B23 EPR Capable Set to ‘1 if EPR Capable. B22 Reserved Reserved – Shall be set to zero. B21…20 Peak Current Peak Current value. B19…10 Voltage Voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 142 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the USB Suspend Supported flag is cleared, then the Sink Shall Not apply the [USB 2.0], [USB 3.2] or [USB4] rules for suspend and May continue to draw the Negotiated power. Note: When USB is suspended, the USB device state is also suspended. Sinks May indicate to the Source that they would prefer to have the USB Suspend Supported flag cleared by setting the No USB Suspend flag in a Request Message (see Section 6.4.2.5, "No USB Suspend"). 6.4.1.2.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.2.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sources capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.2.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Data bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.2.1.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.1.2.1.7 EPR Mode Capable The EPR Capable bit is a Static bit that Shall be set if the Source is designed to supply more than 100W and operate in EPR Mode. When this bit is set, an EPR Source:  Operating in SPR Mode Shall only send an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Message  May only enter EPR Mode when the Cable and the Sink also report that they are EPR Capable. 6.4.1.2.1.8 Peak Current The USB Power Delivery Fixed Supply is only required to deliver the amount of current requested in the Operating Current field (IoC) of an RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current (see Section 7.2.8, "Sink Peak Current Operation") period needed to maintain such average power. The Peak Current field allows a Source to Advertise this additional capability. This capability is intended for direct Port to Port connections only and Shall Not be offered to downstream Sinks via a Hub. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 143 Every Fixed Supply PDO Shall contain a Peak Current field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current field in the corresponding Fixed Supply PDO (see Table 6.10, "Fixed Power Source Peak Current Capability"). Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding Fixed Supply PDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall also set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send the Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. 6.4.1.2.2 Variable Supply (non-Battery) Power Data Object Table 6.11, "Variable Supply (non-Battery) PDO – Source" describes a Variable Supply (non-Battery) (10b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall define the range that output voltage Shall fall within. This does not indicate the voltage that will be supplied, except it Shall fall within that range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. The Minimum Voltage field value Shall Not be less than 80% of the Maximum Voltage field value. 6.4.1.2.3 Battery Supply Power Data Object Table 6.12, "Battery Supply PDO – Source" describes a Battery Supply (01b) PDO for a Source. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall represent the Battery's voltage range. The Battery Shall be capable of supplying the Power value over the entire voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: The Battery Supply PDO uses power instead of current. Table 6.10 Fixed Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Table 6.11 Variable Supply (non-Battery) PDO – Source Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Current Maximum current in 10mA units Page 144 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Sink May monitor the Battery voltage. Table 6.12 Battery Supply PDO – Source Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Maximum Allowable Power Maximum allowable power in 250mW units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 145 6.4.1.2.4 Augmented Power Data Object (APDO) The voltage fields define the output voltage range over which the power supply Shall be adjustable in 20mV steps in SPR PPS Mode and 100mV steps in both SPR AVS Mode and EPR AVS Mode. The Maximum Current field contains the current the Programmable Power Supply Shall be capable of delivering over the Advertised voltage range. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. 6.4.1.2.4.1 SPR Programmable Power Supply APDO Table 6.13, "SPR Programmable Power Supply APDO – Source" below describes the SPR PPS (1100b) APDO for a Source operating in SPR Mode and supplying 5V up to 21V. The PPS APDO is used primarily for Sink Directed Charge Directed Charge of a Battery in the Sink. When applying a current to the Battery greater than the cable supports, a high efficiency fixed voltage scaler May be used in the Sink to reduce the cable current. 6.4.1.2.4.1.1 PPS Power Limited When the PPS Power Limited bit is set, the SPR PPS Source Shall operate in the same way as if the PPS Power Limited bit is clear (see Section 7.1.4.2, "SPR Programmable Power Supply (PPS)" with the below exception:  May supply power that exceeds the Source's rated PDP within the Optional operating area in Figure 7.7, "SPR PPS Constant Power". When the PPS Power Limited bit is cleared, the SPR PPS Source Shall deliver the Maximum Current field value up to the Maximum Voltage as Advertised in its APDO. The SPR PPS Source Shall Not reject an RDO with an Operating Current field value that is less than or equal to the Maximum Current field value in the APDO even if the requested Operating Current field value is greater than the Source's PDP/requested Output voltage. Table 6.13 SPR Programmable Power Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27 PPS Power Limited Set to ‘1’ when PPS Power Limited B26…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Page 146 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.2.4.2 SPR Adjustable Voltage Supply APDO Table 6.14, "SPR Adjustable Voltage Supply APDO – Source" below describes the SPR AVS (1110b) APDO for a Source operating in SPR Mode and supplying 9V up to 20V. 6.4.1.2.4.2.1 Peak Current The Peak Current field follows the same definition as for the Peak Current field (see Section 6.4.1.2.1.8, "Peak Current" and Table 6.10, "Fixed Power Source Peak Current Capability". 6.4.1.2.4.3 EPR Adjustable Voltage Supply APDO Table 6.15, "EPR Adjustable Voltage Supply APDO – Source" below describes the EPR AVS (1101b) APDO for a Source operating in EPR Mode and supplying 15V up to 48V. 6.4.1.2.4.3.1 PDP The PDP field Shall contain the AVS Port's PDP. See Section 10.2.3.3, "Optional Normative Extended Power Range (EPR)" and Figure 10.6, "Valid EPR AVS Operating Region" for more information regarding how PDP in the AVS APDO relates to maximum available current. 6.4.1.2.4.3.2 Peak Current The USB Power Delivery EPR AVS is only required to deliver the amount of current requested in the Operating Current field (IoC) of an AVS RDO. In some usages however, for example computer systems, where there are short bursts of activity, it might be desirable to overload the Source for short periods. For example, when a computer system tries to maintain average power consumption, the higher the peak current, the longer the low current period needed to maintain such average power (see Section 7.2.8, "Sink Peak Current Operation"). The Peak Current (Source EPR AVS) field allows a Source to Advertise this additional capability. This Table 6.14 SPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…26 Peak Current Peak Current (see Table 6.10, "Fixed Power Source Peak Current Capability")) B25…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the maximum voltage in the SPR AVS range is 15V. Table 6.15 EPR Adjustable Voltage Supply APDO – Source Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Peak Current (Source EPR AVS) Peak Current (see Table 6.16, "EPR AVS Power Source Peak Current Capability") B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 147 capability is intended for direct Port to Charger connections only and Shall Not be offered to downstream Sinks via a Hub. Every EPR AVS APDO Shall contain a Peak Current (Source EPR AVS) field. Supplies that want to offer a set of overload Capabilities Shall Advertise this through the Peak Current (Source EPR AVS) field in the corresponding EPR AVS APDO (see Table 6.16, "EPR AVS Power Source Peak Current Capability". Supplies that do not support an overload capability Shall set these bits to 00b in the corresponding EPR AVS APDO. Supplies that support an extended overload capability specified in the PeakCurrent1…3 fields of the Source_Capabilities_Extended Message (see Section 6.5.1, "Source_Capabilities_Extended Message") Shall set these bits to 00b. Sinks wishing to utilize these Extended Capabilities Shall first send a Get_Source_Cap_Extended Message to determine what Capabilities, if any are supported by the Source. Table 6.16 EPR AVS Power Source Peak Current Capability Bits 21…20 Description 00 Peak current equals IoC (default) or look at the Source_Capabilities_Extended Message (send Get_Source_Cap_Extended Message) 01 Overload Capabilities: 1. Peak current equals 150% IoC for 1ms @ 5% duty cycle (low current equals 97% IoC for 19ms) 2. Peak current equals 125% IoC for 2ms @ 10% duty cycle (low current equals 97% IoC for 18ms) 3. Peak current equals 110% IoC for 10ms @ 50% duty cycle (low current equals 90% IoC for 10ms) 10 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 150% IoC for 2ms @ 10% duty cycle (low current equals 94% IoC for 18ms) 3. Peak current equals 125% IoC for 10ms @ 50% duty cycle (low current equals 75% IoC for 10ms) 11 Overload Capabilities: 1. Peak current equals 200% IoC for 1ms @ 5% duty cycle (low current equals 95% IoC for 19ms) 2. Peak current equals 175% IoC for 2ms @ 10% duty cycle (low current equals 92% IoC for 18ms) 3. Peak current equals 150% IoC for 10ms @ 50% duty cycle (low current equals 50% IoC for 10ms) Page 148 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.3 Sink Power Data Objects This section lists the types of PDOs a Sink can use in an SPR or EPR Capabilities Message. 6.4.1.3.1 Sink Fixed Supply Power Data Object Table 6.17, "Fixed Supply PDO – Sink" describes the Sink Fixed Supply (00b) PDO. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Sink Shall set the Voltage field to its required voltage and the Operational Current field to its required operating current. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. Since all USB Consumers support vSafe5V, the required vSafe5V Fixed Supply Power Data Object is also used to convey additional information that is returned in bits 29 through 20. All other Fixed Supply Power Data Objects Shall set bits 29…20 to zero. For a Sink requiring no power from the Source, the Voltage field Shall be set to 5V and the Operational Current field Shall be set to 0mA. 6.4.1.3.1.1 Dual-Role Power The Dual-Role Power bit Shall be set when the Port is Dual-Role Power capable i.e., supports the PR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role. If the Dual-Role Power bit is set to one in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Power bit is set to zero in the Source_Capabilities Message the Dual-Role Power bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.2 Higher Capability In the case that the Sink needs more than vSafe5V (e.g., 15V) to provide full functionality, then the Higher Capability bit Shall be set. 6.4.1.3.1.3 Unconstrained Power The Unconstrained Power bit Shall be set when an external source of power is available that is sufficient to adequately power the system while charging external devices, or when the device's primary function is to charge external devices. Table 6.17 Fixed Supply PDO – Sink Bit(s) Field Description B31…30 Fixed Supply 00b - Fixed Supply PDO B29 Dual-Role Power Set to ‘1’ if Dual-Role Power supported B28 Higher Capability Set to ‘1’ if Higher Capability supported B27 Unconstrained Power Set to ‘1’ if Unconstrained Power supported B26 USB Communications Capable Set to ‘1’ if USB Communications Capable B25 Dual-Role Data Dual-Role Data B24...23 Fast Role Swap required USB Type-C Current Fast Role Swap required USB Type-C current (see also [USB Type-C 2.4]): Value Description 00b Fast Role Swap not supported (default) 01b Default USB Port 10b 1.5A@5V 11b 3.0A@5V B22...20 Reserved Reserved – Shall be set to zero. B19…10 Voltage Voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 149 To set the Unconstrained Power bit because of an external source, the external source of power Should be either:  An AC Supply, e.g., a Charger, directly connected to the Sink.  Or, in the case of a PDUSB Hub:  A PD Source with its Unconstrained Power bit set.  Multiple PD Sources all with their Unconstrained Power bits set. 6.4.1.3.1.4 USB Communications Capable The USB Communications Capable bit Shall only be set for Sinks capable of communication over the USB data lines (e.g., D+/- or SS Tx/Rx). 6.4.1.3.1.5 Dual-Role Data The Dual-Role Data bit Shall be set when the Port is Dual-Role Data capable i.e., it supports the DR_Swap Message. This is a Static capability which Shall remain fixed for a given device regardless of the device's present Power Role or Data Role. If the Dual-Role Data bit is set to one in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to one. If the Dual-Role Dataa bit is set to zero in the Source_Capabilities Message the Dual-Role Data bit in the Sink_Capabilities Message Shall also be set to zero. 6.4.1.3.1.6 Fast Role Swap USB Type-C Current The Fast Role Swap required USB Type-C Current field Shall indicate the current level the Sink will require after a Fast Role Swap has been performed. The Initial Source Shall Not transmit a Fast Role Swap Request if the Fast Role Swap required USB Type-C Current field is set to zero. Initially when the New Source applies vSafe5V it will have Rd asserted but Shall provide the USB Type-C current indicated by the New Sink in this field. If the New Source is not able to supply this level of current, it Shall Not perform a Fast Role Swap. When Rp is asserted by the New Source during the Fast Role Swap AMS (see Section 6.3.19, "FR_Swap Message"), the value of USB Type-C current indicated by Rp Shall be the same or greater than that indicated in the Fast Role Swap required USB Type-C Current field. 6.4.1.3.2 Variable Supply (non-Battery) Power Data Object Table 6.18, "Variable Supply (non-Battery) PDO – Sink" describes a Variable Supply (non-Battery) (10b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Current field Shall be set to the operational current that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Required operating current is defined as the amount of current a given device needs to be functional. This value could be the maximum current the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.3 Battery Supply Power Data Object Table 6.19, "Battery Supply PDO – Sink" describes a Battery Supply (01b) PDO used by a Sink. See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. Table 6.18 Variable Supply (non-Battery) PDO – Sink Bit(s) Field Description B31…30 Variable Supply 01b - Variable Supply (non-Battery) PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Current Operational current in 10mA units Page 150 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The voltage fields Shall be set to the output voltage range that the Sink requires to operate. The Operational Power field Shall be set to the operational power that the Sink requires at the given voltage range. The absolute voltage, including any voltage variation, Shall Not fall below the Minimum Voltage field value and Shall Not exceed the Maximum Voltage field value. Note: Only the Battery Supply PDO uses power instead of current. Required operating power is defined as the amount of power a given device needs to be functional. This value could be the maximum power the Sink will ever require or could be sufficient to operate the Sink in one of its modes of operation. 6.4.1.3.4 Augmented Power Data Objects See Section 7.1.3, "Types of Sources" for the electrical requirements of the power supply. The Maximum and Minimum voltage fields Shall be set to the output voltage range that the Sink requires to operate. 6.4.1.3.4.1 SPR Programmable Power Supply APDO Table 6.20, "SPR Programmable Power Supply APDO – Sink" below describes a SPR PPS APDO for a Sink operating in SPR Mode and consuming 21V or less. The Maximum Current field Shall be set to the maximum current the Sink requires over the voltage range. The maximum current is defined as the maximum amount of current the device needs to fully support its function (e.g., Sink Directed Charge). Table 6.19 Battery Supply PDO – Sink Bit(s) Field Description B31…30 Battery Supply 10b - Battery Supply PDO B29…20 Maximum Voltage Maximum voltage in 50mV units B19…10 Minimum Voltage Minimum voltage in 50mV units B9…0 Operational Power Operational Power in 250mW units Table 6.20 SPR Programmable Power Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR PPS 00b – SPR PPS B27…25 Reserved Reserved – Shall be set to zero. B24…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7 Reserved Reserved – Shall be set to zero. B6...0 Maximum Current Maximum current in 50mA increments Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 151 6.4.1.3.4.2 SPR Adjustable Voltage Supply APDO Table 6.21, "SPR Adjustable Voltage Supply APDO – Sink" below describes the SPR AVS (1110b) APDO for a Sink operating in SPR AVS Mode. The Maximum Current 15V/Maximum Current 20V fields in the SPR AVS APDO for the Sink is defined as the maximum current the device needs to fully support its function. 6.4.1.3.4.3 EPR Adjustable Voltage Supply APDO Table 6.22, "EPR Adjustable Voltage Supply APDO – Sink" below describes a EPR AVS APDO for a Sink operating in EPR AVS Mode. The PDP field in the EPR AVS APDO for the Sink is defined as the PDP the device needs to fully support its function. 6.4.1.4 SPR Capabilities Message Construction An SPR Capabilities Message (Source_Capabilities Message or Sink_Capabilities Message) Shall have at least one Power Data Object for vSafe5V. The SPR Capabilities Message Shall also contain the sending Port's information followed by up to 6 additional Power Data Objects. Power Data Objects in an SPR Capabilities Message Shall be sent in the following order: 1) The vSafe5V Fixed Supply PDO Shall always be the first (A)PDO. 2) The remaining Fixed Supply PDOs, if present, Shall be sent in voltage order; lowest to highest. 3) The Battery Supply PDOs if present Shall be sent in Minimum voltage order; lowest to highest. 4) The Variable Supply (non-Battery) PDOs, if present, Shall be sent in Minimum voltage order; lowest to highest. 5) The SPR AVS APDO, if present, Shall be sent. 6) The Programmable Power Supply APDOs, if present, Shall be sent in Maximum voltage order, lowest to highest. Note: The EPR Capabilities Message construction is defined in Section 6.5.15.1, "EPR Capabilities Message Construction". Table 6.21 SPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 SPR AVS 10b – SPR AVS B27…20 Reserved Reserved – Shall be set to zero. B19…10 Maximum Current 15V For 9V – 15V range: Maximum current in 10mA units equal to the Maximum Current field of the 15V Fixed Supply PDO B9…0 Maximum Current 20V For 15V – 20V range: Maximum Current in 10mA units equal to the Maximum Current field of the 20V Fixed Supply PDO, set to 0 if the Maximum voltage in the SPR AVS range is 15V. Table 6.22 EPR Adjustable Voltage Supply APDO – Sink Bit(s) Field Description B31…30 APDO 11b – Augmented Power Data Object (APDO) B29…28 EPR AVS 01b – EPR AVS B27…26 Reserved Reserved – Shall be set to zero. B25…17 Maximum Voltage Maximum voltage in 100mV increments B16 Reserved Reserved – Shall be set to zero. B15…8 Minimum Voltage Minimum voltage in 100mV increments B7…0 PDP PDP in 1W increments Page 152 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.12, "SPR Capabilities Message Construction" describes the construction of an SPR Capabilities Message. The Message will always have at least one Fixed Supply 5V PDO and may have up to six more PDOs depending on the Source Capabilities. Figure 6.12 SPR Capabilities Message Construction Figure 6.13 Example Capabilities Message with 2 Power Data Objects In the 27W Source as shown in Figure 6.13, "Example Capabilities Message with 2 Power Data Objects", the Number of Data Objects field is 2: vSafe5V plus one other voltage. Power Data Objects (PDO) and Augmented Power Data Objects (APDO) are identified by the Message Header's Message Type field. They are used to form SPR Capabilities Messages. 6.4.1.5 SPR Source Capabilities Message Sources send a Source_Capabilities Message either as part of advertising Port Capabilities, or in response to a Get_Source_Cap Message. See Section 6.5.15.2, "EPR_Source_Capabilities Message" for information about EPR Source Capabilities Messages. Following a Hard Reset, a power-on event or plug insertion event, a Source Port Shall send a Source_Capabilities Message after every SourceCapabilityTimer timeout as an Advertisements that Shall be interpreted by the Sink Port on Attachment. The Source Shall continue sending a minimum of nCapsCount Source_Capabilities Messages until a GoodCRC Message is received. Additionally, a Source_Capabilities Message Shall only be sent by a Port in the following cases:  By the Source Port from the PE_SRC_Ready state upon a change in its ability to supply power to this Port.  By a Source Port or Dual-Role Power Port in response to a Get_Source_Cap Message.  Optionally by a Source Port from the PE_SRC_Ready state when available power in a multi-Port system changes, even if the Source Capabilities for this Port have not changed. A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual- Role Power ports presently operating as a Sink. Each Power Data Object Shall describe a specific Source capability such as a Battery (e.g., 2.8-4.1V) or a Fixed Supply (e.g., 15V) at a maximum allowable current. The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sources Shall minimally offer one Power Data Object that reports vSafe5V. A Source Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Source capability and voltage. Header 2 bytes PDO 1 PDO 2 PDO 3 PDO 4 PDO 5 PDO 6 PDO 7 001b 010b 011b 100b 101b 110b 111b Header No. of Data Objects = 2 Fixed 5V PDO Fixed 9V PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 153 Sinks with Accessory Support do not source VBUS (see [USB Type-C 2.4]). Sinks with Accessory Support are still considered Sources when sourcing VCONN to an Accessory even though VBUS is not applied; in this case they Shall Advertise vSafe5V with the Maximum Current field set to 0mA in the first Power Data Object. The main purpose of this is to enable the Sink with Accessory Support to get into the PE_SRC_Ready State to enter an Alternate Mode. A Sink in SPR Mode Shall evaluate every Source_Capabilities Message it receives and Shall respond with a Request Message. If its power consumption exceeds the Source Capabilities it Shall Re-negotiate so as not to exceed the Source's most recently Advertised Capabilities. A Sink, in SPR Mode, in an Explicit Contract with a PPS APDO, Shall periodically re-request the PPS APDO at least every tPPSRequest until either:  The Sink requests something other than PPS APDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. A Sink in EPR Mode that receives a Source_Capabilities Message in response to a Get_Source_Cap Message Shall Not respond with a Request Message. If a Sink in EPR Mode receives a Source_Capabilities Message, not in response to a Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. A Source that has accepted a Request Message with a Programmable RDO Shall issue Hard Reset Signaling if it has not received a Request Message with a Programmable RDO within tPPSTimeout. The Source Shall discontinue this behavior after:  Receiving a Request Message with a Fixed Supply, Variable Supply or Battery Supply RDO.  There is a Power Role Swap.  There is a Hard Reset.  There is Error Recovery. 6.4.1.6 SPR Sink Capabilities Message Sinks send a Sink_Capabilities Message (see Section 6.4.2, "Request Message") in response to a Get_Sink_Cap Message. See Section 6.5.15.3, "EPR_Sink_Capabilities Message" for more information about the Capabilities Message. A USB Power Delivery capable Sink, upon detecting vSafe5V on VBUS and after a SinkWaitCapTimer timeout without seeing a Source_Capabilities Message, Shall send a Hard Reset. If the Attached Source is USB Power Delivery capable, it responds by sending Source_Capabilities Messages thus allowing power Negotiations to begin. A Sink Port Shall report power levels it is able to operate at in a series of 32-bit Power Data Objects (see Section Table 6.7, "Power Data Object"). These are returned as part of a Sink_Capabilities Message in response to a Get_Sink_Cap Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). This is similar to that used for Source Port Capabilities with equivalent Power Data Objects for Fixed Supply, Variable Supply and Battery Supply as defined in this section. Power Data Objects are used to convey the Sink Port's operational power requirements including Dual-Role Power Ports presently operating as a Source. Each Power Data Object Shall describe a specific Sink operational power level, such as a Battery Supply (e.g., 2.8- 4.1V) or a Fixed Supply (e.g., 15V). The Number of Data Objects field in the Message Header Shall define the number of Power Data Objects that follow the Message Header in a Data Message. All Sinks Shall minimally offer one Power Data Object with a power level at which the Sink can operate. A Sink Shall Not offer multiple Power Data Objects of the same type (Fixed Supply, Variable Supply, Battery Supply) and the same voltage but Shall instead offer one Power Data Object with the highest available current for that Sink capability and voltage. All Sinks Shall include one Power Data Object that reports vSafe5V even if they require additional power to operate fully. In the case where additional power is required for full operation the Higher Capability bit Shall be set. Page 154 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.1.6.1 Use by Dual-Role Power devices Dual-Role Power devices send a Source_Capabilities Message (see Section 6.4.1.5, "SPR Source Capabilities Message") as part of advertising Port Capabilities when operating in Source role. Dual-Role Power devices send a Source_Capabilities Message in response to a Get_Source_Cap Message regardless of their present operating role. Similarly Dual-Role Power devices send a Sink_Capabilities Message (see Section 6.4.1.6, "SPR Sink Capabilities Message") in response to a Get_Sink_Cap Message regardless of their present operating role. 6.4.1.6.2 Management of the Power Reserve This section has been removed. Refer to Section 8.2.5, "Managing Power Requirements". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 155 6.4.2 Request Message A Request Message Shall be sent by a Sink to request power during the request phase of an SPR power Negotiation. The Request Data Object Shall be returned by the Sink making a request for power. It Shall be sent in response to the most recent Source_Capabilities Message (see Section 8.3.2.2, "Power Negotiation") when in SPR Mode. A Request Message Shall return one and only one Sink Request Data Object that Shall identify the Power Data Object being requested. The Source Shall respond to a Request Message with an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Request Message includes the requested power level. For example, if the Source_Capabilities Message includes a Fixed Supply PDO that offers 9V @ 1.5A and if the Sink only wants 9V @ 0.5A, it will set the Operating Current field to 50 (i.e., 10mA * 50 = 0.5A). The request uses a different format depending on the kind of power requested.  The Fixed Supply Power Data Object and Variable Supply Power Data Object share a common format shown in Table 6.23, "Fixed and Variable Request Data Object".  The Battery Supply Power Data Object uses the format shown in Table 6.24, "Battery Request Data Object".  The PPS Request Data Object's format is shown in Table 6.25, "PPS Request Data Object".  The AVS Request Data Object's format is shown in Table 6.26, "AVS Request Data Object". The Request Data Objects are also used by the EPR_Request Message when operating in EPR Mode. See Section 6.4.9, "EPR_Request Message" for information about the use of the EPR_Request Message. A Source operating in EPR Mode that receives a Request Message Shall initiate a Hard Reset. Table 6.23 Fixed and Variable Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0 - Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Current Operating current in 10mA units B9…0 Maximum Operating Current Maximum Operating current 10mA units Page 156 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.24 Battery Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Giveback GiveBack flag = 0- Deprecated and Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21…20 Reserved Reserved – Shall be set to zero. B19…10 Operating Power Operating Power in 250mW units B9…0 Maximum Operating Power Maximum Operating Power in 250mW units Table 6.25 PPS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 20mV units. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Table 6.26 AVS Request Data Object Bit(s) Field Description B31…28 Object Position Object position (0000b and 1110b…1111b are Reserved and Shall Not be used) B27 Reserved Reserved – Shall be set to zero. B26 Capability Mismatch Set to ‘1’ for a Capabilities Mismatch B25 USB Communications Capable Set to ‘1’ if USB Communications Capable B24 No USB Suspend Set to ‘1’ if requesting No USB Suspend B23 Unchunked Extended Messages Supported Set to ‘1’ if Unchunked Extended Messages Supported B22 EPR Capable Set to ‘1’ if EPR Capable B21 Reserved Reserved – Shall be set to zero. B20...9 Output Voltage Output voltage in 25mV units, the least two significant bits Shall be set to zero making the effective voltage step size 100mV. B8...7 Reserved Reserved – Shall be set to zero. B6...0 Operating Current Operating current 50mA units. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 157 6.4.2.1 Object Position The value in the Object Position field Shall indicate which object in the Source_Capabilities Message or EPR_Source_Capabilities Message the RDO refers to. The value 0001b always indicates the 5V Fixed Supply PDO as it is the first object following the Source_Capabilities Message’s Message Header or EPR_Source_Capabilities Message’s Extended Message Header. The number 0010b refers to the next PDO and so forth. The Object Position field values 0001b…0111b Shall only be used to refer to SPR (A)PDOs. SPR (A)PDOs May be requested by either a Request or an EPR_Request Message. Object positions 1000b…1011b Shall only be used to refer to EPR (A)PDOs. EPR (A)PDOs Shall only be requested by an EPR_Request Message. If the Object Position field in a Request Message contains a value greater than 0111b, the Source Shall send Hard Reset Signaling. 6.4.2.2 GiveBack Flag (Deprecated) The Giveback flag has been Deprecated and Shall be set to zero. 6.4.2.3 Capability Mismatch A Capabilities Mismatch occurs when the Source cannot satisfy the Sink's power requirements based on the Source Capabilities it has offered. In this case the Sink Shall make a Valid request from the offered Source Capabilities and Shall set the Capability Mismatch bit (see Section 8.2.5.2, "Power Capability Mismatch"). When a Capabilities Mismatch condition does not exist, the Sink Shall Not set the Capability Mismatch bit. When a Sink returns a Request Data Object with the Capability Mismatch bit set in response to a Source Capabilities Message, it indicates that it wants more power than the Source is currently offering. This can be due to either a specific voltage that is not being offered or there is not sufficient current for the voltages that are being offered. Sources whose Port Reported PDP is less than their Port Present PDP (see Section 6.4.11, "Source_Info Message") Shall respond to the Requests with the Capability Mismatch bit set as follows. The Source within tCapabilitiesMismatchResponse of the PS_RDY Message Shall send a new Source Capabilities Message that offers either: 1) The set of Source Capabilities to minimally satisfy the Sink's requirements based on what it actually requires for full operation by evaluating the: a) Sink_Capabilities_Extended Message(if supported by the Sink) and/or b) Sink_Capabilities or EPR_Sink_Capabilities Message. 2) The set of Source Capabilities the Source can supply at this time based on the Port Present PDP. To prevent looping, Sources Should Not send a new Source Capabilities Message in response to subsequent Request Message with the Capability Mismatch flag set until its Port Present PDP changes. Once a Guaranteed Capability Source that has responded to a Capability Mismatch, it Shall Not subsequently send out another Source Capabilities Message at a lower PDP unless the power required by the Sink (as indicated in its Sink Capabilities Message or Sink_Capabilities_Extended Message) has also been reduced. Sources wishing to manage their power May periodically check the Sink Capabilities Message or Sink_Capabilities_Extended Message to determine whether these have changed. Note: A Source Capabilities Message refers to a Source_Capabilities Message or an EPR_Source_Capabilities Message, and a Sink Capabilities Message refers to a Sink_Capabilities Message or EPR_Sink_Capabilities Message, Request refers to a Request Message or EPR_Request depending on operating mode. In this context a Valid Request Message means the following:  The Object Position field Shall contain a reference to an object that was present in the last received Source Capabilities Message.  The Operating Current/Operating Power field Shall contain a value which is less than or equal to the maximum current/power offered by the selected (A)PDO the Source Capabilities Message. Page 158 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.2.4 USB Communications Capable The USB Communications Capable flag Shall be set to one when the Sink has USB data lines and is capable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. The USB Communications Capable flag Shall be set to zero when the Sink does not have USB data lines or is otherwise incapable of communicating using either [USB 2.0], [USB 3.2] or [USB4] protocols. This is used by the Source to determine operation in certain cases such as USB suspend. If the USB Communications Capable flag has been set to zero by a Sink, then the Source needs to be aware that USB Suspend rules cannot be observed by the Sink. 6.4.2.5 No USB Suspend The No USB Suspend flag May be set by the Sink to indicate to the Source that this device is requesting to continue its Explicit Contract during USB Suspend. Sinks setting this flag typically have functionality that can use power for purposes other than USB Communication e.g., for charging a Battery. The Source uses this flag to evaluate whether it Should re-issue the Source_Capabilities Message with the USB Suspend Supported flag cleared. 6.4.2.6 Unchunked Extended Messages Supported The Unchunked Extended Messages Supported bit Shall be set when the Port can send and receive Extended Messages with Data Size > MaxExtendedMsgLegacyLen bytes in a single, Unchunked Extended Message. 6.4.2.7 EPR Mode Capable The EPR Capable bit Shall indicate whether or not the Sink is capable of operating in EPR Mode. When the Sink's ability to operate in EPR Mode changes, it Shall send a new Request Message with the updated EPR Capable bit set in the RDO. 6.4.2.8 Operating Current The Operating Current field in the Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. A new Request Message or EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The Operating Current field in the SPR Programmable Request Data Object is used in addition by the Sink to request the Source for the Current Limit level it needs. When the request is accepted the Source's output current supplied into any load Shall be less than or equal to the Operating Current value. When the Sink attempts to consume more current, the Source Shall reduce the output voltage so as not to exceed the Operating Current value. The Operating Current field in the AVS Request Data Object Shall be set to the highest current the Sink will draw during the Explicit Contract. Note: A Source in AVS Mode, unlike the SPR Source in PPS Mode, does not support current limit; the Sink is responsible not to take more current than it requested. A new Request / EPR_Request Message, with an updated Operating Current value, Shall be issued whenever the Sink's power needs change. The value in the Operating Current field Shall Not exceed the value in the Maximum Current field of the Source_Capabilities Message. For EPR AVS, the Operating Current field Shall Not exceed the PDP / Output voltage rounded down to the nearest 50 mA. This field Shall apply to the Fixed Supply, Variable Supply, Programmable and AVS RDOs. 6.4.2.9 Maximum Operating Current The Maximum Operating Current field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Current field in the Request Message or EPR_Request Message, the field Shall be set equal to the value of the Operating Current field. To ensure backward compatibility, the Source Should Ignore this field. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 159 This field Shall apply to the Fixed Supply and Variable Supply RDO in SPR Mode and the Fixed Supply RDO in EPR Capable. 6.4.2.10 Operating Power The Operating Power field in the Request Data Object Shall be set to the highest power the Sink will draw throughout the Explicit Contract. This field Shall apply to the Battery Supply RDO. 6.4.2.11 Maximum Operating Power The Maximum Operating Power field has been functionally Deprecated. In order to maintain backward compatibility with Sources that may try to interpret the Maximum Operating Power field in the Request Message, the field Shall be set equal to the value of the Operating Power field. To ensure backward compatibility, the Source Should Ignore this field. This field Shall apply to the Battery Supply RDO. 6.4.2.12 Output Voltage The Output Voltage field in the Programmable and AVS Request Data Objects Shall be set by the Sink to the voltage the Sink requires as measured at the Source's output connector. The Output Voltage field Shall be greater than or equal to the Minimum Voltage field and less than or equal to the Maximum Voltage field in the Programmable Power Supply and AVS APDOs, respectively. This field Shall apply to the Programmable RDO and AVS RDO. 6.4.3 BIST Message The BIST Message is sent to request the Port to enter a PHY Layer test mode (see Section 5.9, "Built in Self-Test (BIST)") that performs one of the following functions:  Enter a Continuous BIST Mode to send a continuous stream of test data to the Tester.  Enter and leave a Shared Capacity Group test mode. The Message format is as shown in Figure 6.14, "BIST Message". Figure 6.14 BIST Message All Ports Shall be able to be a Unit Under Test (UUT) only when operating at vSafe5V. All of the following BIST Modes Shall be supported:  Process reception of a BIST Carrier Mode BIST Data Object that Shall result in the generation of the appropriate carrier signal.  Process reception of a BIST Test Data BIST Data Object that Shall result in the Message being Ignored. UUTs with Ports constituting a Shared Capacity Group (see [USB Type-C 2.4]) Shall support the following BIST Mode:  Process reception of a BIST Shared Test Mode Entry BIST Data Object that Shall cause the UUT to enter BIST Shared Capacity Test Mode; a mode in which the UUT offers its full Source Capabilities on every Port in the Shared Capacity Group. Header No. of Data Objects = 1 or 7 BIST Data Object Page 160 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Process reception of a BIST Shared Test Mode Exit BIST Data Object that Shall cause the UUT to exit the BIST Shared Capacity Test Mode. When a Port receives a BIST Message BIST Data Object for a BIST Mode when not operating at vSafe5V, the BIST Message Shall be Ignored. When a Port receives a BIST Message BIST Data Object for a BIST Mode it does not support the BIST Message Shall be Ignored. When a Port or Cable Plug receives a BIST Message BIST Data Object for a Continuous BIST Mode the Port or Cable Plug enters the requested BIST Mode and Shall remain in that BIST Mode for tBISTContMode and then Shall return to normal operation (see Section 6.6.7.2, "BISTContModeTimer"). The usage model of the PHY Layer BIST Modes generally assumes that some controlling agent will request a test of its Port Partner. In Section 8.3.2.15, "Built in Self-Test (BIST)" there is a sequence description of the test sequences used for compliance testing. The fields in the BIST Data Object are defined in the Table 6.27, "BIST Data Object". 6.4.3.1 BIST Carrier Mode Upon receipt of a BIST Message, with a BIST Carrier Mode BIST Data Object, the UUT Shall send out a continuous string of BMC encoded alternating "1"s and "0"s. The UUT Shall exit the Continuous BIST Mode within tBISTContMode of this Continuous BIST Mode being enabled (see Section 6.6.7.2, "BISTContModeTimer"). 6.4.3.2 BIST Test Data Mode Upon receipt of a BIST Message, with a BIST Test Data BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter BIST Test Data Mode in which it sends no further Messages except for GoodCRC Messages in response to received Messages. See Section 5.9.2, "BIST Test Data Mode" for the definition of the Test Frame. The test Shall be ended by sending Hard Reset Signaling to reset the UUT. Table 6.27 BIST Data Object Bit(s) Value Parameter Description Reference Applicability B31…28 0000b…0100b Reserved Shall Not be used Section 1.4.2 - 0101b BIST Carrier Mode Request Transmitter to enter BIST Carrier Mode Section 6.4.3.1 Mandatory 0110b…0111b Reserved Shall Not be used Section 1.4.2 - 1000b BIST Test Data Sends a Test Frame. Section 6.4.3.2 Mandatory 1001b BIST Shared Test Mode Entry Requests UUT to enter BIST Shared Capacity Test Mode. Section 6.4.3.3.1 Mandatory for UUTs with shared capacity 1010b BIST Shared Test Mode Exit Requests UUT to exit BIST Shared Capacity Test Mode. Section 6.4.3.3.2 Mandatory for UUTs with shared capacity 1011b…1111b Reserved Shall Not be used Section 1.4.2 - B27…0 Reserved Shall be set to zero. Section 1.4.2 - Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 161 6.4.3.3 BIST Shared Capacity Test Mode A Shared Capacity Group of Ports share a common power source that is not capable of simultaneously powering all the ports to their full Source Capabilities (see [USB Type-C 2.4]). The BIST Shared Capacity Test Mode Shall only be implemented by ports in a Shared Capacity Group. The UUT Shared Capacity Group of Ports Shall contain one or more Ports, designated as Master Ports, that recognize both the BIST Shared Test Mode Entry BIST Data Object and the BIST Shared Test Mode Exit BIST Data Object. 6.4.3.3.1 BIST Shared Test Mode Entry When any master Port in a Shared Capacity Group receives a BIST Message with a BIST Shared Test Mode Entry BIST Data Object, while in the PE_SRC_Ready State, the UUT Shall enter a compliance test mode where the maximum Source Capabilities are always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. Ports in the Shared Capacity Group that are not Master Ports Shall Not enter compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Upon receipt of a BIST Message, with a BIST Shared Test Mode Entry BIST Data Object, the UUT Shall return a GoodCRC Message and Shall enter the BIST Shared Capacity Test Mode. On entering this mode, the UUT Shall send a new Source_Capabilities Message from each Port in the Shared Capacity Group within tBISTSharedTestMode. The Tester will not exceed the shared capacity during this mode. 6.4.3.3.2 BIST Shared Test Mode Exit Upon receipt of a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, the UUT Shall return a GoodCRC Message and Shall exit the BIST Shared Capacity Test Mode. If any other Message, aside from a BIST Message, with a BIST Shared Test Mode Exit BIST Data Object, is received while in BIST Shared Capacity Test Mode this Shall Not cause the UUT to exit the BIST Shared Capacity Test Mode On exiting the mode, the UUT May send a new Source_Capabilities Message to each Port in the Shared Capacity Group or the UUT May perform ErrorRecovery on each Port. Ports in the Shared Capacity Group that are not Master Ports Shall Not exit compliance mode on receiving the BIST Shared Test Mode Entry BIST Data Object. Ports in the Shared Capacity Group that are not Master Ports Should Not exit compliance mode on receiving the BIST Shared Test Mode Exit BIST Data Object.  The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off.  The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs:  Hard Reset  Cable Reset  Soft Reset  Data Role Swap  Power Role Swap  Fast Role Swap  VCONN Swap.  The UUT May leave BIST Shared Capacity Test Mode if the Tester makes a request that exceeds the Capabilities of the UUT. Page 162 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4 Vendor Defined Message The Vendor_Defined Message (VDM) is provided to allow vendors to exchange information outside of that defined by this specification. A Vendor_Defined Message Shall consist of at least one Vendor Data Object (VDO), the VDM Header, and May contain up to a maximum of six additional VDOs. To ensure vendor uniqueness of Vendor_Defined Messages, all Vendor_Defined Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. Two types of Vendor_Defined Messages are defined: Structured VDMs and Unstructured VDMs. A Structured VDM defines an extensible structure designed to support Modal Operation. An Unstructured VDM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. The Message format Shall be as shown in Figure 6.15, "Vendor Defined Message". Figure 6.15 Vendor Defined Message The VDM Header Shall be the first 4-byte object in a Vendor Defined Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. Additionally, vendors May make use of the Commands in a Structured VDM. The fields in the VDM Header for an Unstructured VDM, when the VDM Type Bit is set to zero, Shall be as defined in Table 6.28, "Unstructured VDM Header". The fields in the VDM Header for a Structured VDM, when the VDM Type Bit is set to one Shall be as defined in Table 6.29, "Structured VDM Header". Both Unstructured VDMs and Structured VDMs Shall only be sent and received after an Explicit Contract has been established. The only exception to this is the Discover Identity Command which May be sent by Source when a Default Contract or an Implicit Contract (in place after Attach, a Power Role Swap or Fast Role Swap) is in place in order to discover Cable Capabilities (see SSection 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 6.4.4.1 Unstructured VDM The Unstructured VDM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the VID. The Port Partners and Cable Plugs Shall exit any states entered using an Unstructured VDM when a Hard Reset appears on PD. The following rules apply to the use of Unstructured VDM Messages:  Unstructured VDMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract Unstructured VDMs Shall Not be sent and Shall be Ignored if received.  Only the DFP Shall be an Initiator of Unstructured VDMs.  Only the UFP or a Cable Plug Shall be a Responder to Unstructured VDM.  Unstructured VDMs Shall Not be initiated or responded to under any other circumstances. Header No. of Data Objects = 1-7 VDM Header 0-6 VDOs Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 163  Unstructured VDMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can Unstructured VDMs be sent or received. The Active Mode and the associated Unstructured VDMs Shall use the same SVID.  Unstructured VDMs May be used with SOP* Packets.  When a DFP or UFP does not support Unstructured VDMs or does not recognize the VID it Shall return a Not_Supported Message. Table 6.28, "Unstructured VDM Header" illustrates the VDM Header bits. 6.4.4.1.1 USB Vendor ID The Vendor ID (VID) field Shall contain the 16-bit Vendor ID value assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. 6.4.4.1.2 VDM Type The VDM Type field Shall be set to zero indicating that this is an Unstructured VDM. 6.4.4.2 Structured VDM Setting the VDM Type field to 1 (Structured VDM) defines the use of bits B14…0 in the Structured VDM Header. The fields in the Structured VDM Header are defined in Table 6.29, "Structured VDM Header". The following rules apply to the use of Structured VDM Messages:  Structured VDMs Shall only be used when an Explicit Contract is in place with the following exception:  Prior to establishing the First Explicit Contract, a Source May issue Discover Identity Messages, to a Cable Plug using SOP’ Packets, as an Initiator (see Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram").  Either Port May be an Initiator of Structured VDMs except for the Enter Mode and Exit Mode Commands which Shall only be initiated by the DFP.  A Cable Plug Shall only be a Responder to Structured VDMs.  Structured VDMs Shall Not be initiated or responded to under any other circumstances.  When a DFP or UFP does not support Structured VDMs any Structured VDMs received Shall return a Not_Supported Message.  When using any of the SVID Specific Commands in the Structured VDM Header (VDM Header b4…0 - value 16 - 31) the Responder Shall NAK Messages where the SVID in the VDM Header is not recognized as an SVID that uses SVID Specific Commands or the use of SVID Specific Commands is not supported for the SVID.  When a Cable Plug does not support Structured VDMs any Structured VDMs received Shall be Ignored. Table 6.28 Unstructured VDM Header Bit(s) Parameter Description B31…16 Vendor ID (VID) Unique 16-bit unsigned integer. Assigned by the USB-IF to the Vendor. B15 VDM Type 0 = Unstructured VDM B14…0 Available for Vendor Use Content of this field is defined by the vendor. Page 164 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A DFP, UFP or Cable Plug which supports Structured VDMs and receiving a Structured VDM for a SVID that it does not recognize Shall reply with a NAK Command. Table 6.29 Structured VDM Header Bit(s) Field Description B31…16 Standard or Vendor ID (SVID) Unique 16-bit unsigned integer, assigned by the USB-IF B15 VDM Type 1 = Structured VDM B14…13 Structured VDM Version (Major) Version Number (Major) of the Structured VDM (not this specification Version):  Version 1.0 = 00b (Deprecated and Shall Not be used)  Version 2.x = 01b  Values 2-3 are Reserved and Shall Not be used B12…11 Structured VDM Version (Minor) For Commands 0…15 Version Number (Minor) of the Structured VDM  Version 2.0 = 00b (Used for ports implemented prior to USB PD Revision 3.1, Version 1.6)  Version 2.1 = 01b (Used for ports implemented starting with USB PD Revision 3.1, Version 1.6)  All other Values are Reserved and Shall Not be used  SVID Specific Commands (16…31) defined by the SVID. B10…8 Object Position For the Enter Mode, Exit Mode, and Attention Commands (Requests/ Responses):  000b = Reserved and Shall Not be used.  001b…110b = Index into the list of VDOs to identify the desired Alternate Mode VDO  111b = Exit all Active Modes (equivalent of a power on reset). Shall  only be used with the Command. Commands 0…3, 7…15:  000b  001b…111b = Reserved and Shall Not be used. SVID Specific Commands (16…31) defined by the SVID. B7…6 Command Type 00b = REQ (Request from Initiator Port) 01b = ACK (Acknowledge Response from Responder Port) 10b = NAK (Negative Acknowledge Response from Responder Port) 11b = BUSY (Busy Response from Responder Port) B5 Reserved Shall be set to zero and Shall be Ignored B4…01 Command 0 = Reserved and Shall Not be used. 1 = Discover Identity 2 = Discover SVIDs 3 = Discover Modes 4 = Enter Mode 5 = Exit Mode 6 = Attention 7-15 = Reserved and Shall Not be used. 16…31 = SVID Specific Commands 1) In the case where a SID is used the modes are defined by a standard. When a VID is used the modes are defined by the Vendor. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 165 Section Table 6.30, "Structured VDM Commands" shows the Commands, which SVID to use with each Command and the SOP* values which Shall be used. 6.4.4.2.1 SVID The Standard or Vendor ID (SVID) field Shall contain either a 16-bit USB Standard ID value (SID) or the 16-bit assigned to the vendor by the USB-IF (VID). No other value Shall be present in this field. Section Table 6.31, "SVID Values" lists specific SVID values referenced by this specification. 6.4.4.2.2 VDM Type The VDM Type field Shall be set to one indicating that this is a Structured VDM. 6.4.4.2.3 Structured VDM Version The Structured VDM Version (Major)/Structured VDM Version (Minor) fields indicate the level of functionality supported in the Structured VDM part of the specification. This is not the same Version as the Version of this specification. The Structured VDM Version (Major) Shall be set to 01b to indicate Version 2.x with the Structured VDM Version (Minor) field set as appropriate based on whether the Port is implemented to USB PD Revision 3.1, Version 1.6 (or newer) or a prior Version. To ensure interoperability with existing PDUSB products, PDUSB products Shall support every Structured VDM Version number starting from Version 1.0. On receipt of a VDM Header with a higher Version number than it supports, a Port or Cable Plug Shall respond using the highest Version number it supports. On receipt of a VDM Header with a lower Version number than it supports, a Port or Cable Plug Shall respond using the same Version number it received. The Structured VDM Version (Major)/Structured VDM Version (Minor) fields of the Discover Identity Command sent and received during the Discovery Process Shall be used to determine the lowest common Structured VDM Version supported by the Port Partners or Cable Plug and Shall continue to operate using this Specification Revision until they are Detached. After discovering the Structured VDM Version, the Structured VDM Version (Major)/ Structured VDM Version (Minor) fields Shall match the agreed common Structured VDM Version. Table 6.30 Structured VDM Commands Command VDM Header SVID Field SOP* used Discover Identity Shall only use the PD SID. Shall only use SOP/SOP’. Discover SVIDs Shall only use the PD SID. Shall only use SOP/SOP’. Discover Modes Valid with any SVID. Shall only use SOP/SOP’. Enter Mode Valid with any SVID. Valid with SOP*. Exit Mode Valid with any SVID. Valid with SOP*. Attention Valid with any SVID. Valid with SOP*. SVID Specific Commands Valid with any SVID. Valid with SOP* (defined by SVID). Table 6.31 SVID Values Parameter Value Description PD SID 0xFF00 Standard ID allocated to this specification by USB-IF. DPTC SID 0xFF01 Standard ID allocated to [DPTC2.1] by USB-IF. Page 166 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.2.4 Object Position The Object Position field Shall be used by the Enter Mode and Exit Mode Commands. The Discover Modes Command returns a list of zero to six VDOs, each of which describes an Alternate Mode. The value in Object Position field is an index into that list that indicates which VDO (e.g., Alternate Mode) in the list the Enter Mode and Exit Mode Command refers to. The Object Position Shall start with one for the first Alternate Mode in the list. If the SVID is a VID, the content of the VDO for the Alternate Mode Shall be defined by the vendor. If the Standard or Vendor ID (SVID) is a SID, the value Shall be assigned, by the USB-IF, to the given Standard. The VDO's content May be as simple as a numeric value or as complex as bit mapped description of Capabilities of the Alternate Mode. In all cases, the Responder is responsible for deciphering the contents to know whether or not it supports the Alternate Mode at the Object Position. This field Shall be set to zero in the Request or Response (REQ, ACK, NAK or BUSY) when not required by the specification of the individual Command. 6.4.4.2.5 Command Type 6.4.4.2.5.1 Commands other than Attention This Command Type field Shall be used to indicate the type of Command request/response being sent. An Initiator Shall set the Command Type field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then the responses are as follows:  "Responder ACK" is the normal return and Shall be sent to indicate that the Command request was received and handled normally.  "Responder NAK" Shall be returned when the Command request:  Has an Invalid parameter (e.g., Invalid SVID or Alternate Mode).  Cannot be acted upon because the configuration is not correct (e.g., an Alternate Mode which has a dependency on another Alternate Mode or a request to exit an Alternate Mode which is not anActive Mode).  Is an Unrecognized Message.  The handling of "Responder NAK" is left up to the Initiator.  "Responder BUSY" Shall be sent in the response to a VDM when the Responder is unable to respond to the Command request immediately, but the Command request May be retried. The Initiator Shall wait tVDMBusy after a "Responder BUSY" response is received before retrying the Command request. 6.4.4.2.5.2 Attention Command This Command Type field Shall be used to indicate the type of Command request being sent. An Initiator Shall set the field to REQ to indicate that this is a Command request from an Initiator. If Structured VDMs are supported, then no response Shall be made to an Attention Command. 6.4.4.2.6 Command 6.4.4.2.6.1 Commands other than Attention The Command field contains the value for the VDM Command being sent. The Commands explicitly listed in the Command field are used to identify devices and manage their operational Modes. There is a further range of Command values left for the vendor to use to manage additional extensions. A Structured VDM Command consists of a Command request and a Command response (ACK, NAK or BUSY). A Structured VDM Command is deemed to be completed (and if applicable, the transition to the requested functionality is made) when the GoodCRC Message has been successfully received by the Responder in reply to its Command response. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 167 If Structured VDMs are supported, but the Structured VDM Command request is an Unrecognized Message, it Shall be NAKed (see Table 6.32, "Commands and Responses"). 6.4.4.2.6.2 Attention Command The Command field contains the value for the VDM Command being sent (Attention). The Attention Command May be used by the Initiator to notify the Responder that it requires service. A Structured VDM Attention Command consists of a Command request but no Command response. A Structured VDM Attention Command is deemed to be completed when the GoodCRC Message has been successfully received by the Initiator in reply to its Attention Command request. If Structured VDMs are supported, but the Structured VDM Attention Command request is an Unrecognized Message it Shall be Ignored (see Table 6.32, "Commands and Responses"). 6.4.4.3 Use of Commands The VDM Header for a Structured VDM Message defines Commands used to retrieve a list of SVIDs the device supports, to discover the Modes associated with each SVID, and to enter/exit the Modes. The Commands include:  Discover Identity  Discover SVIDs  Discover Modes  Enter Mode  Exit Mode  Attention Additional Command space is also Reserved for Standard and Vendor use and for future extensions. The Command AMSs use the terms Initiator and Responder to identify messaging roles the ports are taking on relative to each other. This role is independent of the Port's power capability (Provider, Consumer etc.) or its present Power Role (Source or Sink). The Initiator is the Port sending the initial Command request and the Responder is the Port replying with the Command response. See Section 6.4.4.4, "Command Processes". All Ports that support Modes Shall support the Discover Identity, Discover SVIDs, the Discover Modes, the Enter Mode and Exit Mode Commands. Table 6.32, "Commands and Responses" details the responses a Responder May issue to each Command request. Responses not listed for a given Command Shall Not be sent by a Responder. A NAK response Should be taken as an indication not to retry that particular Command. Examples of Command usage can be found in Appendix C, "VDM Command Examples". Table 6.32 Commands and Responses Command Allowed Response Reference Discover Identity ACK, NAK, BUSY Section 6.4.4.3.1 Discover SVIDs ACK, NAK, BUSY Section 6.4.4.3.2 Discover Modes ACK, NAK, BUSY Section 6.4.4.3.3 Enter Mode ACK, NAK Section 6.4.4.3.4 Exit Mode ACK, NAK Section 6.4.4.3.5 Attention None Section 6.4.4.3.6 Page 168 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1 Discover Identity The Discover Identity Command is provided to enable an Initiator to identify its Port Partner and for an Initiator (VCONN Source) to identify the Responder (Cable Plug or VPD). The Discover Identity Command is also used to determine whether a Cable Plug or VPD is PD-Capable by looking for a GoodCRC Message Response. The Discover Identity Command Shall only be sent to SOP when there is an Explicit Contract. The Discover Identity Command Shall be used to determine whether a given Cable Plug or VPD is PD Capable (see Section 8.3.3.21.1, "Initiator Structured VDM Discover Identity State Diagram" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). In this case a Discover Identity Command request sent to SOP’ Shall Not cause a Soft Reset if a GoodCRC Message response is not returned since this can indicate a non-PD Capable cable or VPD. Note: A Cable Plug or VPD will not be ready for PD Communication until tVCONNStable after VCONN has been applied (see [USB Type-C 2.4]). During Cable Plug or VPD discovery, when there is an Explicit Contract, Discover Identity Commands are sent at a rate defined by the DiscoverIdentityTimer (see Section 6.6.15, "DiscoverIdentityTimer") up to a maximum of nDiscoverIdentityCount times (see Section 6.7.5, "Discover Identity Counter"). A PD-Capable Cable Plug or VPD Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP’. The Discover Identity Command Shall be used to determine the identity and/or Capabilities of the Port Partner. The following products Shall return a Discover Identity Command ACK in response to a Discover Identity Command request sent to SOP:  A PD-Capable UFP that supports Modal Operation.  A PD-Capable product that has multiple DFPs.  A PD-Capable [USB4] product. The SVID in the Discover Identity Command request Shall be set to the PD SID (see Section Table 6.31, "SVID Values"). The Number of Data Objects field in the Message Header in the Discover Identity Command request Shall be set to 1 since the Discover Identity Command request Shall Not contain any VDOs. The Discover Identity Command ACK sent back by the Responder Shall contain an ID Header VDO, a Cert Stat VDO, a Product VDO and the Product Type VDOs defined by the Product Type as shown in Figure 6.16, "Discover Identity Command response". This specification defines the following Product Type VDOs:  Passive Cable VDO (see Section 6.4.4.3.1.6, "Passive Cable VDO")  Active Cable VDOs (see Section 6.4.4.3.1.7, "Active Cable VDOs")  VCONN Powered USB Device (VPD) VDO (see Section 6.4.4.3.1.9, "VCONN Powered USB Device VDO")  UFP VDO (see Section 6.4.4.3.1.4, "UFP VDO")  DFP VDO (see Section 6.4.4.3.1.5, "DFP VDO") No VDOs other than those defined in this specification Shall be sent as part of the Discover Identity Command response. Where there is no Product Type VDO defined for a specific Product Type, no VDOs Shall be sent as part of the Discover Identity Command response. Any additional VDOs received by the Initiator Shall be Ignored. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 169 Figure 6.16 Discover Identity Command response The Number of Data Objects field in the Message Header in the Discover Identity Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the product is a DRD both a Product Type (UFP) and a Product Type (DFP) are declared in the ID Header. These products Shall return Product Type VDOs for both UFP and DFP beginning with the UFP VDO, then by a 32-bit Pad Object (defined as all '0's), followed by the DFP VDO as shown in Figure 6.17, "Discover Identity Command response for a DRD". Figure 6.17 Discover Identity Command response for a DRD 6.4.4.3.1.1 ID Header VDO The ID Header VDO contains information corresponding to the Power Delivery Product. The fields in the ID Header VDO Shall be as defined in Section Table 6.33, "ID Header VDO". Table 6.33 ID Header VDO Bit(s) Description Reference B31 USB Communications Capable as USB Host Section 6.4.4.3.1.1.1  Shall be set to one if the product is capable of enumerating USB Devices.  Shall be set to zero otherwise. B30 USB Communications Capable as a USB Device Section 6.4.4.3.1.1.2  Shall be set to one if the product is capable of being enumerated as a USB Device.  Shall be set to zero otherwise B29…27 SOP Product Type (UFP) Section 6.4.4.3.1.1.3  000b – Not a UFP  001b – PDUSB Hub  010b – PDUSB Peripheral  011b – PSD  100b…111b – Reserved, Shall Not be used. SOP’ Product Type (Cable Plug/VPD)  000b – Not a Cable Plug/VPD  001b…010b – Reserved, Shall Not be used.  011b – Passive Cable  100b – Active Cable  101b – Reserved, Shall Not be used.  110b – VCONN Powered USB Device (VPD)  111b – Reserved, Shall Not be used. Header No. of Data Objects = 4-71 VDM Header ID Header VDO Cert Stat VDO 0..32 Product Type VDO(s) Product VDO 1. Only Data objects defined in this specification can be sent as part of the Discover Identity Command. 2. The following sections define the number and content of the VDOs for each Product Type. Header No. of Data Objects = 7 VDM Header ID Header VDO Cert Stat VDO Product VDO Product Type VDO(s) yp ( ) UFP Pad DFP Page 170 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.1 USB Communications Capable as a USB Host The USB Communications Capable as USB Host field is used to indicate whether or not the Port has a USB Host Capability. 6.4.4.3.1.1.2 USB Communications Capable as a USB Device The USB Communications Capable as a USB Device field is used to indicate whether or not the Port has a USB Device Capability. 6.4.4.3.1.1.3 Product Type (UFP) The SOP Product Type (UFP) field indicates the type of Product when in UFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP Product Type (UFP) field Shall be the closest categorization of the main functionality of the Product in UFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in UFP role regardless of the present Data Role. Table 6.34, "Product Types (UFP)" defines the Product Type VDOs which Shall be returned. B26 Modal Operation Supported Section 6.4.4.3.1.1.4  Shall be set to one if the product (UFP/Cable Plug) is capable of supporting Modal Operation (Alternate Modes).  Shall be set to zero otherwise. B25…23 SOP - Product Type (DFP) Section 6.4.4.3.1.1.6  000b – Not a DFP  001b – PDUSB Hub  010b – PDUSB Host  011b – Power Brick  100b…111b – Reserved, Shall Not be used. SOP’: Reserved, Shall Not be used. B22…21 Connector Type Section 6.4.4.3.1.1.7  00b – Reserved, for compatibility with legacy systems.  01b – Reserved, Shall Not be used.  10b – USB Type-C Receptacle  11b – USB Type-C Plug B20…16 Reserved, Shall Not be used. B15…0 USB Vendor ID Section 6.4.4.3.1.1.8 [USB 2.0]/[USB 3.2]/[USB4] Table 6.34 Product Types (UFP) Product Type Description Product Type VDO Reference Undefined Shall be used when this is not a UFP. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PDUSB Peripheral Shall be used when the Product is a PDUSB Device other than a PDUSB Hub. UFP VDO Section 6.4.4.3.1.4 PSD Shall be used when the Product is a PSD, e.g., power bank. None Table 6.33 ID Header VDO (Continued) Bit(s) Description Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 171 6.4.4.3.1.1.4 Product Type (Cable Plug) The SOP’ Product Type (Cable Plug/VPD) field indicates the type of Product when the Product is a Cable Plug or VPD, whether a VDO will be returned and if so the type of VDO to be returned. Table 6.35, "Product Types (Cable Plug/ VPD)" defines the Product Type VDOs which Shall be returned. 6.4.4.3.1.1.5 Modal Operation Supported The Modal Operation Supported bit is used to indicate whether or not the Product (either a Cable Plug or a device that can operate in the UFP role) is capable of supporting Modes. The Modal Operation Supported bit does not describe a DFP's Alternate Mode Controller functionality. A product that supports Modal Operation Shall respond to the Discover SVIDs Command with a list of SVIDs for all of the Modes it is capable of supporting whether or not those Modes can currently be entered. 6.4.4.3.1.1.6 Product Type (DFP) The SOP - Product Type (DFP) field indicates the type of Product when in DFP Data Role, whether a VDO will be returned and if so the type of VDO to be returned. The Product Type indicated in the SOP - Product Type (DFP) field Shall be the closest categorization of the main functionality of the Product in DFP Data Role or "Undefined" when there is no suitable category for the product. For DRD Products this field Shall always indicate the Product Type when in DFP role regardless of the present Data Role. Table 6.36, "Product Types (DFP)" defines the Product Type VDOs which Shall be returned. In SOP’ Communication (Cable Plugs and VPDs) this bit field is Reserved and Shall be set to zero. 6.4.4.3.1.1.7 Connector Type Field The Connector Type field (B22…21) Shall contain a value identifying it as either a USB Type-C receptacle or a USB Type-C plug. Table 6.35 Product Types (Cable Plug/VPD) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None Active Cable Shall be used when the Product is a cable that incorporates signal conditioning circuits. Active Cable VDO Section 6.4.4.3.1.7 Passive Cable Shall be used when the Product is a cable that does not incorporate signal conditioning circuits. Passive Cable VDO Section 6.4.4.3.1.6 VCONN Powered USB Device Shall be used when the Product is a PDUSB VCONN Powered USB Device. VPD VDO Section 6.4.4.3.1.9 Table 6.36 Product Types (DFP) Product Type Description Product Type VDO Reference Undefined Shall be used where no other Product Type value is appropriate. None PDUSB Hub Shall be used when the Product is a PDUSB Hub. DFP VDO Section 6.4.4.3.1.7 PDUSB Host Shall be used when the Product is a PDUSB Host or a PDUSB host that supports one or more Alternate Modes as an AMC. DFP VDO Section 6.4.4.3.1.6 Charger Shall be used when the Product is a Charger. DFP VDO Section 6.4.4.3.1.9 Page 172 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.1.8 Vendor ID Manufacturers Shall set the USB Vendor ID field to the value of the Vendor ID assigned to them by USB-IF. For USB Devices or Hubs which support USB Communications the USB Vendor ID field Shall be identical to the Vendor ID field defined in the product's USB Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.4.4.3.1.2 Cert Stat VDO The Cert Stat VDO Shall contain the XID assigned by USB-IF to the product before certification in binary format. The fields in the Cert Stat VDO Shall be as defined in Table 6.37, "Cert Stat VDO". 6.4.4.3.1.3 Product VDO The Product VDO contains identity information relating to the product. The fields in the Product VDO Shall be as defined in Table 6.38, "Product VDO". Manufacturers Should set the USB Product ID field to a unique value identifying the product and Should set the bcdDevice field to a version number relevant to the release version of the product. 6.4.4.3.1.4 UFP VDO The UFP VDO defined in this section Shall be returned by Ports capable of operating as a UFP including traditional USB peripherals, USB Hub's upstream Port and DRD capable host Ports. The UFP VDO defined in this section Shall be sent when the Product Type (UFP) field in the ID Header VDO is given as a PDUSB Peripheral or PDUSB Hub. Table 6.39, "UFP VDO" defines the UFP VDO that Shall be sent based on the Product Type. A [USB4] UFP Shall support the Structured VDM Discover Identity Command. Table 6.37 Cert Stat VDO Bit(s) Description Reference B31...0 32-bit unsigned integer, XID Assigned by USB-IF Table 6.38 Product VDO Bit(s) Description Reference B31...16 16-bit unsigned integer, USB Product ID [USB 2.0]/[USB 3.2] B15...0 16-bit unsigned integer, bcdDevice [USB 2.0]/[USB 3.2] Table 6.39 UFP VDO Bit(s) Description Reference B31…29 UFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.3 = 011b Values 100b…111b are Reserved, Shall Not be used. B28 Reserved Shall be set to zero. B27…24 Device Capability Bit Description 0 [USB 2.0] Device Capable 1 [USB 2.0] Device Capable (Billboard only) 2 [USB 3.2] Device Capable 3 [USB4] Device Capable B23…22 Connector Type (Legacy) Deprecated, Shall be set to 00b. B21…11 Reserved Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 173 6.4.4.3.1.4.1 VDO Version Field The UFP VDO Version field contains a VDO Version for this VDM Version number. This field indicates the expected content for the UFP VDOs. 6.4.4.3.1.4.2 Device Capability Field The Device Capability bit-field describes the UFP's Capabilities when operating as either a PDUSB Device or PDUSB Hub. B10…8 VCONN Power When the VCONN Required field is set to “Yes” the VCONN Power Field indicates the VCONN power needed by the AMA for full functionality:  000b = 1W  001b = 1.5W  010b = 2W  011b = 3W  100b = 4W  101b = 5W  110b = 6W 111b = Reserved, Shall Not be used. When the VCONN Required field is set to “No” the VCONN Power field is Reserved and Shall be set to zero. B7 VCONN Required Indicates whether the AMA requires VCONN in order to function.  0 = No  1 = Yes When the Alternate Modes field indicates no modes are supported, the VCONN Required field is Reserved and Shall be set to zero. B6 VBUS Required Indicates whether the AMA requires VBUS in order to function.  0 = Yes  1 = No When the Alternate Modes field indicates no modes are supported, the VBUS Required field is Reserved and Shall be set to zero. B5…3 Alternate Modes Bit Description 0 Supports [TBT3] Alternate Mode 1 Supports Alternate Modes that reconfigure the signals on the [USB Type-C 2.4] connector – except for [TBT3]. 2 Supports Alternate Modes that do not reconfigure the signals on the [USB Type-C 2.4] connector. B2…0 USB Highest Speed  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b =[USB4] Gen4  101b…111b = Reserved and Shall be set to zero. Table 6.39 UFP VDO (Continued) Bit(s) Description Reference Page 174 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The bits in the bit-field Shall be non-zero when the corresponding USB Device speed is supported and Shall be set to zero when the corresponding USB Device speed is not supported. [USB 2.0] "Device capable" and "Device capable Billboard only" (bits 0 and 1) Shall Not be simultaneously set. 6.4.4.3.1.4.3 Connector Type Field Th Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.4.4 VCONN Power Field When the VCONN Required field indicates that VCONN is required the VCONN Power field Shall indicate how much power an AMA needs in order to fully operate. When the VCONN Required field is set to "No" the VCONN Power field is Reserved and Shall be set to zero. 6.4.4.3.1.4.5 VCONN Required Field The VCONN Required field Shall indicate whether VCONN is needed for the AMA to operate. The VCONN Required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.6 VBUS Required Field The VBUS Required field Shall indicate whether VBUS is needed for the AMA to operate. The VBUS required field Shall only be used if the Alternate Modes field indicates that an Alternate Mode is supported. If no Alternate Modes are supported, this field is Reserved and Shall be set to zero. 6.4.4.3.1.4.7 Alternate Modes Field The Alternate Modes field Shall be used to identify all the types of Alternate Modes, if any, a device supports. 6.4.4.3.1.4.8 USB Highest Speed Field The USB Highest Speed field Shall indicate the Port's highest speed capability. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 175 6.4.4.3.1.5 DFP VDO The DFP VDO Shall be returned by Ports capable of operating as a DFP; including those implemented by Hosts, Hubs and Power Bricks. The DFP VDO Shall be returned when the Product Type (DFP) field in the ID Header VDO is given as Power Brick, PDUSB Host or PDUSB Hub. Table 6.40, "DFP VDO" defines the DFP VDO that Shall be sent. 6.4.4.3.1.5.1 VDO Version Field The DFP VDO Version field Shall contain a VDO Version for this VDM Version number. This field indicates the expected content for the DFP VDO. 6.4.4.3.1.5.2 Host Capability Field The Host Capability bit-field Shall describe whether the DFP can operate as a PDUSB Host and the DFP's Capabilities when operating as a PDUSB Host. Power Bricks and PDUSB Hubs Shall set the Host Capability bits to zero. 6.4.4.3.1.5.3 Connector Type Field The Connector Type (Legacy) field was previously used for the UFP VDO's Connector Type. Shall be set to 00b by the Cable Plug and Shall be Ignored by the receiver. The receiver can find this information in the Connector Type field in the ID Header VDO (Section 6.4.4.3.1.1.7, "Connector Type Field"). 6.4.4.3.1.5.4 Port Number Field The Port Number field Shall be a Static unique number that unambiguously identifies each [USB Type-C 2.4] DFP, including DRPs, on the device. Note: This number is independent of the USB Port number. Table 6.40 DFP VDO Bit(s) Field Description B31…29 DFP VDO Version Version Number of the VDO (not this specification Version):  Version 1.2 = 010b Values 011b…111b are Reserved and Shall Not be used B28…27 Reserved Shall be set to zero. B26…24 Host Capability Bit Description 0 [USB 2.0] Host Capable 1 [USB 3.2] Host Capable 2 [USB4] Host Capable B23…22 Connector Type (Legacy) Shall be set to 00b. B21…5 Reserved Shall be set to zero. B4…0 Port Number Unique Port number to identify a specific Port on a multi-Port device. Page 176 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.6 Passive Cable VDO The Passive Cable VDO defined in this section Shall be sent when the Product Type is given as Passive Cable. Table 6.41, "Passive Cable VDO" defines the Cable VDO which Shall be sent. A Passive Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. A Passive Cable Shall Not incorporate data bus signal conditioning circuits and hence has no concept of Super Speed Directionality. A Passive Cable Shall include a VBUS wire and Shall only respond to SOP’ Communication. Passive Cables Shall support the Structured VDM Discover Identity Command and Shall return the Passive Cable VDO in a Discover Identity Command ACK as shown in Table 6.41, "Passive Cable VDO". Table 6.41 Passive Cable VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive (Passive Cable)  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Passive Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency (Passive Cable)  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b – > 70ns (>~7m) Note: 1001b ….1111b Reserved and Shall Not be used B12…11 Cable Termination Type (Passive Cable)  00b = VCONN not required. Cable Plugs that only support Discover Identity Commands Shall set these bits to 00b.  01b = VCONN required  10b…11b = Reserved and Shall Not be used B10…9 Maximum VBUS Voltage (Passive Cable) Maximum Cable VBUS Voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 177 6.4.4.3.1.6.1 HW Version Field The HW Version (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.6.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.6.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.6.4 USB Type-C plug to USB Type-C/Captive Field The USB Type-C plug to USB Type-C/Captive (Passive Cable) field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.6.5 EPR Mode Capable The EPR Capable (Passive Cable) bit is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.6.6 Cable Latency Field The Cable Latency (Passive Cable) field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. 6.4.4.3.1.6.7 Cable Termination Type Field The Cable Termination Type (Passive Cable) field (B12…11) Shall contain a value indicating whether the Passive Cable needs VCONN only initially in order to support the Discover Identity Command, after which it can be removed, or the Passive Cable needs VCONN to be continuously applied in order to power some feature of the Cable Plug. 6.4.4.3.1.6.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Passive Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated using a Fixed Supply over the cable as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage (Passive Cable) field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Passive B6…5 VBUS Current Handling Capability (Passive Cable)  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4…3 Reserved Shall be set to zero. B2…0 USB Highest Speed (Passive Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.41 Passive Cable VDO (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 178 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Passive Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.6.9 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Passive Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. 6.4.4.3.1.6.10 USB Highest Speed Field The USB Highest Speed (Passive Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 179 6.4.4.3.1.7 Active Cable VDOs An Active Cable has a USB Plug on each end at least one of which is a Cable Plug supporting SOP’ Communication. An Active Cable Shall incorporate data bus signal conditioning circuits and May have a concept of Super Speed Directionality on its Super Speed wires. An Active Cable May include a VBUS wire. An Active Cable:  Shall respond to SOP’ Communication.  May respond to SOP’’ Communication.  Shall support the Structured VDM Discover Identity Command.  In the Discover Identity Command ACK:  Shall set the Product Type in the ID Header VDO to Active Cable.  Shall return the Active Cable VDOs defined in Table 6.42, "Active Cable VDO1" and Table 6.43, "Active Cable VDO2".. Table 6.42 Active Cable VDO1 Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b Values 001b…111b are Reserved and Shall Not be used. B20 Reserved Shall be set to zero. B19…18 USB Type-C plug to USB Type-C/Captive  00b = Reserved and Shall Not be used  01b = Reserved and Shall Not be used  10b = USB Type-C  11b = Captive B17 EPR Capable (Active Cable)  0b – Cable is not EPR Capable  1b = Cable is EPR Capable B16…13 Cable Latency  0000b – Reserved and Shall Not be used  0001b – <10ns (~1m)  0010b – 10ns to 20ns (~2m)  0011b – 20ns to 30ns (~3m)  0100b – 30ns to 40ns (~4m)  0101b – 40ns to 50ns (~5m)  0110b – 50ns to 60ns (~6m)  0111b – 60ns to 70ns (~7m)  1000b –1000ns (~100m)  1001b –2000ns (~200m)  1010b – 3000ns (~300m)  1001b ….1111b Reserved and Shall Not be used Note: Includes latency of electronics in Active Cable. B12…11 Cable Termination Type (Active Cable)  00b…01b = Reserved and Shall Not be used  10b = One end Active, one end passive, VCONN required  11b = Both ends Active, VCONN required 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Page 180 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 B10…9 Maximum VBUS Voltage (Active Cable) Maximum Cable VBUS voltage2:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V B8…7 Reserved Shall be set to zero. B8 SBU Supported  0 = SBU connections supported  1 = SBU connections are not supported B7 SBU Type When SBU Supported = 1 this bit Shall be Ignored When SBU Supported = 0:  0 = SBU is passive  1 = SBU is active B6…5 VBUS Current Handling Capability (Active Cable) When VBUS Through Cable is “No”, this field Shall be Ignored. When VBUS Through Cable is “Yes”:  00b = Reserved and Shall Not be used  01b = 3A  10b = 5A  11b = Reserved and Shall Not be used B4 VBUS Through Cable  0 = No  1 = Yes B3 SOP’’ Controller Present  0 = No SOP’’ controller present  1 = SOP’’ controller present B2…0 USB Highest Speed (Active Cable)  000b = [USB 2.0] only, no SuperSpeed support  001b = [USB 3.2] Gen1  010b = [USB 3.2]/[USB4] Gen2  011b = [USB4] Gen3  100b = [USB4] Gen4  101b…111b = Reserved and Shall Not be used Table 6.43 Active Cable VDO2 Bit(s) Field Description B31…24 Maximum Operating Temperature The maximum internal operating temperature in °C. It might or might not reflect the plug’s skin temperature. B23…16 Shutdown Temperature The temperature, in °C, at which the cable will go into thermal shutdown so as not to exceed the allowable plug skin temperature. B15 Reserved Shall be set to zero. B14…12 U3/CLd Power  000b: >10mW  001b: 5-10mW  010b: 1-5mW  011b: 0.5-1mW  100b: 0.2-0.5mW  101b: 50-200µW  110b: <50µW  111b: Reserved and Shall Not be used Table 6.42 Active Cable VDO1 (Continued) Bit(s) Field Description 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. 2) EPR Sinks with a captive cable Shall report 50V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 181 6.4.4.3.1.7.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.7.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.7.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for the Active Cable VDOs. 6.4.4.3.1.7.4 Connector Type Field The USB Type-C plug to USB Type-C/Captive field (B19…18) Shall contain a value indicating whether the opposite end from the USB Type-C plug is another USB Type-C plug (i.e., a detachable Standard USB Type-C Cable Assembly) or is a Captive Cable Assembly. 6.4.4.3.1.7.5 EPR Mode Capable The EPR Capable (Active Cable) is a Static bit which Shall only be set when the cable is specifically designed for safe operation when carrying up to 48 volts at 5 amps. 6.4.4.3.1.7.6 Cable Latency Field The Cable Latency field (B16…13) Shall contain a value corresponding to the signal latency through the cable which can be used as an approximation for its length. B11 U3 to U0 transition mode  0b: U3 to U0 direct  1b: U3 to U0 through U3S B10 Physical connection  0b = Copper  1b = Optical B9 Active element  0b = Active Re-driver  1b = Active Re-timer B8 USB4 Supported  0b = [USB4] supported  1b = [USB4]not supported B7…6 USB 2.0 Hub Hops Consumed Number of [USB 2.0] ‘hub hops’ cable consumes. Shall be set to zero if USB 2.0 not supported. B5 USB 2.0 Supported  0b = [USB 2.0] supported  1b = [USB 2.0] not supported B4 USB 3.2 Supported  0b = [USB 3.2] SuperSpeed supported  1b = [USB 3.2] SuperSpeed not supported B3 USB Lanes Supported  0b = One lane  1b = Two lanes B2 Optically Isolated Active Cable  0b = No  1b = Yes B1 USB4 Asymmetric Mode Supported  0b = No  1b = Yes Shall be set to zero if asymmetry is not supported. B0 USB Gen  0b = Gen 1  1b = Gen 2 or higher Note: See VDO1 USB Highest Speed for details of Gen supported. Table 6.43 Active Cable VDO2 (Continued) Bit(s) Field Description Page 182 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.7.7 Cable Termination Type Field The Cable Termination Type (Active Cable) field (B12…11) Shall contain a value corresponding to whether the Active Cable has one or two Cable Plugs requiring power from VCONN. 6.4.4.3.1.7.8 Maximum VBUS Voltage Field The Maximum VBUS Voltage (Active Cable) field (B10…9) Shall contain the maximum voltage that Shall be Negotiated as part of an Explicit Contract where the maximum voltage that Shall be applied to the cable is vSrcNew max + vSrcValid max. When this field is set to 20V, the cable will safely carry a Programmable Power Supply APDO of 20V where the absolute maximum voltage that can be applied to the cable is 21.55V. Similarly, when the Maximum VBUS Voltage (Active Cable) field is 50V, a Fixed Supply of 48V can be Negotiated as part of an Explicit Contract where the absolute maximum voltage that can be applied to the cable is 50.9V. Maximum VBUS Voltage (Active Cable) field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.7.9 SBU Supported Field The SBU Supported field (B8) Shall indicate whether the cable supports the SBUs in the cable. 6.4.4.3.1.7.10 SBU Type Field The SBU Type field (B7) Shall indicate whether the SBUs are passive or active (e.g., digital). 6.4.4.3.1.7.11 VBUS Current Handling Capability Field The VBUS Current Handling Capability (Active Cable) field (B6…5) Shall indicate whether the cable is capable of carrying 3A or 5A. The VBUS Current Handling Capability (Active Cable) field Shall only be Valid when the VBUS Current Handling Capability (Active Cable) field indicates an end-to-end VBUS wire. 6.4.4.3.1.7.12 VBUS Through Cable Field The VBUS Through Cable field (B4) Shall indicate whether the cable contains an end-to-end VBUS wire. 6.4.4.3.1.7.13 SOP'' Controller Present Field The SOP’’ Controller Present field (B3) Shall indicate whether one of the Cable Plugs is capable of SOP’’ Communication in addition to the Normative SOP’ Communication. 6.4.4.3.1.7.14 USB Highest Speed Field The USB Highest Speed (Active Cable) field (B2…0) Shall indicate the highest rate the cable supports. The DFP Shall consider all values indicated in this field that are higher than the highest value that the DFP recognizes as being Valid and functionally compatible with the highest speed that the DFP supports. 6.4.4.3.1.7.15 Maximum Operating Temperature Field Maximum Operating Temperature field (B31…24) Shall report the maximum allowable operating temperature inside the plug in °C. 6.4.4.3.1.7.16 Shutdown Temperature Field Shutdown Temperature field (B23…16) Shall indicate the temperature inside the plug, in °C, at which the plug will shut down its active signaling components. When this temperature is reached, it will be reported in the Active Cable Status Message through the Thermal Shutdown bit. 6.4.4.3.1.7.17 U3/CLd Power Field The U3/CLd Power field (B14…12) Shall indicate the power the cable consumes while in [USB 3.2] U3 or [USB4] CLd. 6.4.4.3.1.7.18 U3 to U0 Transition Mode Field The U3 to U0 transition mode field (B11) Shall indicate which U3 to U0 mode the cable supports. This does not include the power in U3S if supported. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 183 6.4.4.3.1.7.19 Physical Connection Field The Physical connection field (B10) Shall indicate the cable's construction, whether the connection between the active elements is copper or optical. 6.4.4.3.1.7.20 Active element Field The Active element field (B9) Shall indicate the cable's active element, whether the active element is a re-timer or a re-driver. 6.4.4.3.1.7.21 USB4 Supported Field The USB4 Supported field (B8) Shall indicate whether or not the cable supports [USB4] operation. 6.4.4.3.1.7.22 USB 2.0 Hub Hops Consumed field The USB 2.0 Hub Hops Consumed field (B7…6) Shall indicate the number of USB 2.0 'hub hops' that are lost due to the transmission time of the cable. 6.4.4.3.1.7.23 USB 2.0 Supported Field The USB 2.0 Supported field (B5) Shall indicate whether or not the cable supports [USB 2.0] only signaling. 6.4.4.3.1.7.24 USB 3.2 Supported Field The USB 3.2 Supported field (B4) Shall, indicate whether or not the cable supports [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.25 USB Lanes Supported Field The USB Lanes Supported field (B3) Shall indicate whether the cable supports one or two lanes of [USB 3.2] SuperSpeed signaling. 6.4.4.3.1.7.26 Optically Isolated Active Cable Field The Optically Isolated Active Cable field (B2) Shall indicate whether this cable is an optically isolated Active Cable or not (as defined in [USB Type-C 2.4]). Optically Isolated Active Cables Shall have a re-timer or linear re-driver (LRD) as the active element and do not support [USB 2.0] or carry VBUS. 6.4.4.3.1.7.27 USB4 Asymmetric Mode Supported Field The USB4 Asymmetric Mode Supported field (B1) Shall indicate that the Active Cable supports asymmetric mode as defined in [USB4] and [USB Type-C 2.4]. 6.4.4.3.1.7.28 USB Gen Field The USB Gen field (B0) Shall indicate the signaling Gen the cable supports. Gen 1 Shall only be used by [USB 3.2] cables as indicated by the USB 3.2 Supported field. Gen 2 or higher May be used by either [USB 3.2] or [USB4] cables as indicated by their respective supported fields. When Gen 2 or higher is indicated the USB Highest Speed (Active Cable) field in VDO1 Shall indicate the actual Gen supported. 6.4.4.3.1.8 Alternate Mode Adapter VDO The Alternate Mode Adapter (AMA) VDO has been Deprecated. PDUSB Devices which support one or more Alternate Modes Shall set an appropriate Product Type (UFP), and Shall set the Modal Operation Supported bit to '1'. Page 184 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.1.9 VCONN Powered USB Device VDO The VCONN Powered USB Device (VPD) VDO defined in this section Shall be sent when the Product Type is given as VCONN Powered USB Device. Table 6.44, "VPD VDO" defines the VPD VDO which Shall be sent. 6.4.4.3.1.9.1 HW Version Field The HW Version field (B31…28) contains a HW version assigned by the VID owner. 6.4.4.3.1.9.2 FW Version Field The Firmware Version field (B27…24) contains a FW version assigned by the VID owner. 6.4.4.3.1.9.3 VDO Version Field The VDO Version field (B23…20) contains a VDO Version for this VDM Version number. This field indicates the expected content for this VDO. 6.4.4.3.1.9.4 Maximum VBUS Voltage Field The Maximum VBUS Voltage field (B16…15) Shall contain the maximum voltage that a Sink Shall Negotiate through the VPD Charge Through Port as part of an Explicit Contract. Note: The maximum voltage that will be applied to the cable is vSrcNew max + vSrcValid max. For example, when the Maximum VBUS Voltage field is 20V, a Fixed Supply of 20V can be Negotiated as part of an Table 6.44 VPD VDO Bit(s) Field Description B31…28 HW Version 0000b…1111b assigned by the VID owner B27…24 Firmware Version 0000b…1111b assigned by the VID owner B23…21 VDO Version Version Number of the VDO (not this specification Version):  Version 1.0 = 000b  Values 001b…111b are Reserved and Shall Not be used. B20...17 Reserved Shall be set to zero. B16…15 Maximum VBUS Voltage Maximum VPD VBUS Voltage:  00b – 20V  01b – 30V1 (Deprecated)  10b – 40V1 (Deprecated)  11b – 50V1 (Deprecated) B14 Charge Through Current Support Charge Through Current Support bit=1b:  0b - 3A capable.  1b - 5A capable Charge Through Current Support bit = 0b:  Reserved and Shall be set to zero. B13 Reserved Shall be set to zero. B12…7 VBUS Impedance Charge Through Current Support bit = 1b: VBUS impedance through the VPD in 2 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Reserved and Shall be set to zero. B6…1 Ground Impedance Charge Through Current Support bit = 1b: Ground impedance through the VPD in 1 mΩ increments. Values less than 10 mΩ are Reserved and Shall Not be used. Charge Through Current Support bit = 0b: Shall be set to zero. B0 Charge Through Support  1b – the VPD supports Charge Through  0b – the VPD does not support Charge Through 1) Values no longer allowed. When present the field Shall be interpreted as if it was 00b. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 185 Explicit Contract where the absolute maximum voltage that can be applied to the cable is 21.55V. Maximum VBUS Voltage field values of 01b and 10b (formerly 30V and 40V) Shall be treated if they were 00b (20V). 6.4.4.3.1.9.5 VBUS Impedance Field The VBUS Impedance field (B12…7) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the VBUS IR Drop limit of 0.5V between the Source and itself. If the Sink can tolerate a larger IR Drop on VBUS it May do so. 6.4.4.3.1.9.6 Ground Impedance Field The Ground Impedance field (B6…1) Shall contain the impedance the VPD adds in series between the Source and the Sink. The Sink Shall take this value into account when requesting current so as to not to exceed the Ground IR Drop limit of 0.25V between the Source and itself. 6.4.4.3.1.9.7 Charge Through Field The Firmware Version field (B0) Shall be set to 1b when the VPD supports Charge Through and 0b otherwise. Page 186 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.2 Discover SVIDs The Discover SVIDs Command is used by an Initiator to determine the SVIDs for which a Responder has Modes. The Discover SVIDs Command is used in conjunction with the Discover Modes Command in the Discovery Process to determine which Modes a device supports. The list of SVIDs is always terminated with one or two 0x0000 SVIDs. The SVID in the Discover SVIDs Command Shall be set to the PD SID (see "Table 6.31, "SVID Values") by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover SVIDs Command request Shall be set to 1 since the Discover SVIDs Command request Shall Not contain any VDOs. The Discover SVIDs Command ACK sent back by the Responder Shall contain one or more SVIDs. The SVIDs are returned 2 per VDO (see Table 6.45, "Discover SVIDs Responder VDO"). If there are an odd number of supported SVIDs, the Discover SVIDs Command is returned ending with a SVID value of 0x0000 in the last part of the last VDO. If there are an even number of supported SVIDs, the Discover SVIDs Command is returned ending with an additional VDO containing two SVIDs with values of 0x0000. A Responder Shall only return SVIDs for which a Discover Modes Command request for that SVID will return at least one Alternate Mode. A Responder that does not support any SVIDs Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover SVIDs Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. If the Responder supports 12 or more SVIDs then the Discover SVIDs Command Shall be executed multiple times until a Discover SVIDs VDO is returned ending either with a SVID value of 0x0000 in the last part of the last VDO or with a VDO containing two SVIDs with values of 0x0000. Each Discover SVID ACK Message, other than the one containing the terminating 0x0000 SVID, Shall convey 12 SVIDs. The Responder Shall restart the list of SVIDs each time a Discover Identity Command request is received from the Initiator. Note: Since a Cable Plug does not retry Messages if the GoodCRC Message from the Initiator becomes corrupted the Cable Plug will consider the Discover SVIDs Command ACK unsent and will send the same list of SVIDs again. Figure 6.18, "Example Discover SVIDs response with 3 SVIDs" shows an example response to the Discover SVIDs Command request with two VDOs containing three SVIDs. Figure 6.19, "Example Discover SVIDs response with 4 SVIDs" shows an example response with two VDOs containing four SVIDs followed by an empty VDO to terminate the response. Figure 6.20, "Example Discover SVIDs response with 12 SVIDs followed by an empty response" shows an example response with six VDOs containing twelve SVIDs followed by an additional request that returns an empty VDO indicating there are no more SVIDs to return. Figure 6.18 Example Discover SVIDs response with 3 SVIDs Table 6.45 Discover SVIDs Responder VDO Bit(s) Field Description B31…16 SVID n 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an even number of SVIDs. B15…0 SVID n+1 16-bit unsigned integer, assigned by the USB-IF or 0x0000 if this is the last VDO and the Responder supports an odd or even number of SVIDs. Header No. of Data Objects = 3 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) 0x0000 (B15..0) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 187 Figure 6.19 Example Discover SVIDs response with 4 SVIDs Figure 6.20 Example Discover SVIDs response with 12 SVIDs followed by an empty response Header No. of Data Objects = 4 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 0x0000 (B31..16) 0x0000 (B15..0) Header No. of Data Objects = 7 VDM Header VDO 1 SVID 0 (B31..16) SVID 1 (B15..0) VDO 2 SVID 2 (B31..16) SVID 3 (B15..0) VDO 3 SVID 4 (B31..16) SVID 5 (B15..0) VDO 4 SVID 6 (B31..16) SVID 7 (B15..0) VDO 5 SVID 8 (B31..16) SVID 9 (B15..0) Header No. of Data Objects = 2 VDM Header VDO 1 0x0000 (B31..16) 0x0000 (B15..0) VDO 6 SVID 10 (B31..16) SVID 11 (B15..0) Page 188 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.4.3.3 Discover Modes The Discover Modes Command is used by an Initiator to determine the Modes a Responder supports for a given SVID. The SVID in the Discover Modes Command Shall be set to the SVID for which Modes are being requested by both the Initiator and the Responder for this Command. The Number of Data Objects field in the Message Header in the Discover Modes Command request Shall be set to 1 since the Discover Modes Command request Shall Not contain any VDOs. The Discover Modes Command ACK sent back by the Responder Shall contain one or more Modes. The Discover Modes Command ACK Shall contain a Message Header with the Number of Data Objects field set to a value of 2 to 7 (the actual value is the number of Alternate Mode objects plus one). If the ID is a VID, the structure and content of the VDO is left to the Vendor. If the ID is a SID, the structure and content of the VDO is defined by the relevant standard’s body. A Responder that does not support any Modes Shall return a NAK. The Number of Data Objects field in the Message Header in the Discover Modes Command NAK and BUSY responses Shall be set to 1 since they Shall Not contain any VDOs. Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes" shows an example of a Discover Modes Command response from a Responder which supports three Modes for a given SVID. Figure 6.21 Example Discover Modes response for a given SVID with 3 Modes 6.4.4.3.4 Enter Mode Command The Enter Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to enter a specified Alternate Mode of operation. Only a DFP Shall initiate the Enter Mode Process which it starts after it has successfully completed the Discovery Process. The value in the Object Position field in the VDM Header Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes"). The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. The Number of Data Objects field in the Message Header in the Command request Shall be set to either 1 or 2 since the Enter Mode Command request Shall Not contain more than 1 VDO. When a VDO is included in an Enter Mode Command request the contents of the 32-bit VDO is defined by the Alternate Mode. The Number of Data Objects field in the Command response Shall be set to 1 since an Enter Mode Command response (ACK, NAK) Shall Not contain any VDOs. Before entering a Alternate Mode, by sending the Enter Mode Command request that requires the reconfiguring of any pins on entry to that Alternate Mode, the Initiator Shall ensure that those pins being reconfigured are placed into the USB Safe State. Before entering an Alternate Mode that requires the reconfiguring of any pins, the Responder Shall ensure that those pins being reconfigured are placed into either USB operation or the USB Safe State. A device May support multiple Modes with one or more active at any point in time. Any interactions between them are the responsibility of the Standard or Vendor. Where there are multiple Active Modes at the same time Modal Operation Shall start on entry to the first Alternate Mode. Header No. of Data Objects = 4 VDM Header Mode 1 Mode 2 Mode 3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 189 On receiving an Enter Mode Command requests the Responder Shall respond with either an ACK or a NAK response. The Responder is not allowed to return a BUSY response. The value in the Object Position field of the Enter Mode Command response Shall contain the same value as the received Enter Mode Command request. If the Responder responds to the Enter Mode Command request with an ACK, the Responder Shall enter the Alternate Mode before sending the ACK. The Initiator Shall enter the Alternate Mode on reception of the ACK. Successful transmission of the Message confirms to the Responder that the Initiator will enter an Active Mode. See Figure 8.111, "DFP to UFP Enter Mode" for more details. If the Responder responds to the Enter Mode Command request with a NAK, the Alternate Mode is not entered. If not presently in Modal Operation the Initiator Shall return to USB operation. If not presently in Modal Operation the Responder Shall remain in either USB operation or the USB Safe State. If the Initiator fails to receive a response within tVDMWaitModeEntry it Shall Not enter the Alternate Mode but return to USB operation. Figure 6.22, "Successful Enter Mode sequence" shows the sequence of events during the transition between USB operation and entering an Alternate Mode. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.23, "Unsuccessful Enter Mode sequence due to NAK" illustrates that when the Responder returns a NAK the transition to an Alternate Mode do not take place and the Responder and Initiator remain in their default USB roles. Figure 6.22 Successful Enter Mode sequence DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC ACK USB Safe State USB USB or USB Safe State New Mode New Mode Page 190 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.23 Unsuccessful Enter Mode sequence due to NAK Once the Alternate Mode is entered, the device Shall remain in that Active Mode until the Exit Mode Command is successful (see Section 6.4.4.3.5, "Exit Mode Command"). The following events Shall also cause the Port Partners and Cable Plug(s) to exit all Active Modes:  A PD Hard Reset.  Error Recovery.  The Port Partners or Cable Plug(s) are Detached.  A Cable Reset (only exits the Cable Plug's Active Modes).  A Data Reset (removing power briefly resets all the Active Modes in the Cable Plug). The Initiator Shall return to USB Operation within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. The Responder Shall return to either USB operation or USB Safe State within tVDMExitMode of a disconnect, of Hard Reset Signaling being detected or Error Recovery. A DR_Swap Message Shall Not be sent during Modal Operation between the Port Partners (see Section 6.3.9, "DR_Swap Message"). 6.4.4.3.5 Exit Mode Command The Exit Mode Command is used by an Initiator (DFP) to command a Responder (UFP or Cable Plug) to exit its Active Mode and return to normal USB operation. Only the DFP Shall initiate the Exit Mode Process. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first DFP (Initiator) UFP (Responder) Enter Mode GoodCRC GoodCRC NAK USB Safe State USB USB or USB Safe State USB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 191 Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 111b in the Object Position field Shall indicate that all Active Modes Shall be exited. The Number of Data Objects field in both the Command request and Command response (ACK, NAK) Shall be set to 1 since an Exit Mode Command Shall Not contain any VDOs. The Responder Shall exit its Active Mode before sending the response Message. The Initiator Shall exit its Active Mode when it receives the ACK. The Responder Shall Not return a BUSY acknowledgment and Shall only return a NAK acknowledgment to a request not containing an Active Mode (i.e., Invalid object position). An Initiator which fails to receive an ACK within tVDMWaitModeExit or receives a NAK or BUSY response Shall exit its Active Mode. See Figure 8.112, "DFP to UFP Exit Mode" for more details. Figure 6.24, "Exit Mode sequence" shows the sequence of events during the transition between exiting an Active Mode and USB operation. It illustrates when the Responder's Alternate Mode changes and when the Initiator's Alternate Mode changes. Figure 6.24 Exit Mode sequence 6.4.4.3.6 Attention The Attention Command May be used by the Initiator to notify the Responder that it requires service. The value in the Object Position field Shall indicate to which Alternate Mode in the Discover Modes Command the VDO refers (see Figure 6.21, "Example Discover Modes response for a given SVID with 3 Modes") and Shall have been used previously in an Enter Mode Command request for an Active Mode. The value 1 always indicates the first Alternate Mode as it is the first object following the VDM Header. The value 2 refers to the next Alternate Mode and so forth. A value of 000b or 111b in the Object Position field Shall Not be used by the Attention Command. DFP (Initiator) UFP (Responder) Exit Mode GoodCRC GoodCRC ACK USB Safe State USB or USB Safe State Mode Mode USB Page 192 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Number of Data Objects field in the Message Header Shall be set to 1 or 2 since the Attention Command Shall Not contain more than 1 VDO. When a VDO is included in an Attention Command the contents of the 32-bit VDO is defined by the Alternate Mode. Figure 6.24, "Exit Mode sequence" shows the sequence of events when an Attention Command is received. Figure 6.25 Attention Command request/response sequence 6.4.4.4 Command Processes The Message flow of Commands during a Process is a query followed by a response. Every Command request sent has to be responded to with a GoodCRC Message. The GoodCRC Message only indicates the Command request was received correctly; it does not mean that the Responder understood or even supports a particular SVID. Figure 6.26, "Command request/response sequence" shows the request/response sequence including the GoodCRC Messages. Initiator Responder GoodCRC Command (Attention) Command Complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 193 Figure 6.26 Command request/response sequence In order for the Initiator to know that the Command request was actually consumed, it needs an acknowledgment from the Responder. There are three responses that indicate the Responder received and processed the Command request:  ACK  NAK  BUSY The Responder Shall complete:  Enter Mode requests within tVDMEnterMode.  Exit Mode requests within tVDMExitMode.  Other requests within tVDMReceiverResponse. An Initiator not receiving a response within the following times Shall timeout and return to either the PE_SRC_Ready or PE_SNK_Ready state (as appropriate):  Enter Mode requests within tVDMWaitModeEntry.  Exit Mode requests within tVDMWaitModeExit.  Other requests within tVDMSenderResponse. The Responder Shall respond with:  ACK if it recognizes the SVID and can process it at this time.  NAK:  if it recognizes the SVID but cannot process the Command request Initiator Responder Command (request) GoodCRC GoodCRC Command (response) Command Complete Page 194 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  or if it does not recognize the SVID  or if it does not support the Command  or if a VDO contains a field which is Invalid.  BUSY if it recognizes the SVID and the Command but cannot process the Command request at this time. The ACK, NAK or BUSY response Shall contain the same SVID as the Command request. 6.4.4.4.1 Discovery Process The Initiator (usually the DFP) always begins the Discovery Process. The Discovery Process has two phases. In the first phase, the Discover SVIDs Command request is sent by the Initiator to get the list of SVIDs the Responder supports. In the second phase, the Initiator sends a Discover Modes Command request for each SVID supported by both the Initiator and Responder. 6.4.4.4.2 Enter Vendor Mode / Exit Vendor Mode Processes The result of the Discovery Process is that both the Initiator and Responder identify the Modes they mutually support. The Initiator (DFP), upon finding a suitable Alternate Mode, uses the Enter Mode Command to enable the Alternate Mode. The Responder (UFP or Cable Plug) and Initiator continue using the Active Mode until the Active Mode is exited. In a managed termination, using the Exit Mode Command, the Active Mode Shall be exited in a controlled manner as described in Section 6.4.4.3.5, "Exit Mode Command". In an unmanaged termination, triggered by:  A Power Delivery Hard Reset (i.e. Hard Reset Signaling sent by either Port Partner) or  By cable Detach (device unplugged) or  By Error Recovery the Active Mode Shall still be exited but there Shall Not be a transition through the USB Safe State. In both the managed and unmanaged terminations, the Initiator and Responder return to USB operation as defined in [USB Type-C 2.4] following an exit from an Alternate Mode. The overall Message flow is illustrated in Figure 6.27, "Enter/Exit Mode Process". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 195 Figure 6.27 Enter/Exit Mode Process 6.4.4.5 VDM Message Timing and Normal PD Messages The timing and interspersing of VDMs between regular PD Messages Shall be done without perturbing the PD AMSs. This requirement Shall apply to both Unstructured VDMs and Structured VDMs. Initiator (DFP) Responder (UFP or Cable Plug) Discover SVIDs List of SVIDs For every DFP supported SVID Modes Supported? N Stay in USB mode Y Enter Mode ACK (Responder switched to Mode) Initiator and Responder operate using Mode Return to USB mode Establish PD Contract Exit Mode or PD Hard Reset or cable unplugged or power removed? Y N USB USB or USB Safe State USB Safe State USB Alternate Mode USB or USB Safe State Alternate Mode USB Discover Modes (SVID) Modes for SVID Page 196 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The use of Structured VDMs by an Initiator Shall Not interfere with the normal PD Message timing requirements nor Shall either the Initiator or Responder interrupt a PD AMS (e.g., Negotiation, Power Role Swap, Data Role Swap etc.). The use of Unstructured VDMs Shall Not interfere with normal PD Message timing. 6.4.5 Battery_Status Message The Battery_Status Message Shall be sent in response to a Get_Battery_Status Message. The Battery_Status Message contains one Battery Status Data Object (BSDO) for one of the Batteries it supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BSDO Shall correspond to the Battery requested in the Battery Status Ref field contained in the Get_Battery_Status Message. The Battery_Status Message returns a BSDO whose format Shall be as shown in Figure 6.28, "Battery_Status Message" and Table 6.46, "Battery Status Data Object (BSDO)". The Number of Data Objects field in the Battery_Status Message Shall be set to 1. Figure 6.28 Battery_Status Message 6.4.5.1 Battery Present Capacity The Battery Present Capacity field Shall return either the Battery's State of Charge (SoC) in tenths of WH or indicate that the Battery's present State of Charge (SOC) is unknown. Table 6.46 Battery Status Data Object (BSDO) Bit(s) Field Description B31…16 Battery Present Capacity Battery’s State of Charge (SoC) in 0.1 WH increments Note: 0xFFFF = Battery’s SOC unknown B15…8 Battery Info Bit Description 0 Invalid Battery Reference Invalid Battery reference 1 Battery Present Battery is present when set 3…2 Battery Charging Status When Battery Present is ‘1’ Shall contain the Battery charging status:  00b: Battery is Charging.  01b: Battery is Discharging.  10b: Battery is Idle.  11b: Reserved, Shall Not be used. When Battery Present is ‘0’:  11b…00b: Reserved, Shall Not be used. 7…4 Reserved, Shall Not be used. B7…0 Reserved Shall be set to zero Header No. of Data Objects = 1 BSDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 197 6.4.5.2 Battery Info The Battery Info field Shall be used to report additional information about the Battery's present status. The Battery Info field's bits Shall reflect the present conditions under which the Battery is operating in the systems. 6.4.5.2.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Status Message contains a reference to a Battery or Battery Slot (see Section 6.5.1.13, "Number of Batteries/Battery Slots Field") that does not exist. 6.4.5.2.2 Battery Present The Battery Present bit Shall be set whenever the Battery is present. It Shall always be set for Batteries that are not Hot Swappable Batteries. For Hot Swappable Batteries, the Battery Present bit Shall indicate whether the Battery is Attached or Detached. 6.4.5.2.3 Battery Charging Status The Battery Charging Status bits indicate whether the Battery is being charged, discharged or is idle (neither charging nor discharging). These bits Shall be set when the Battery Present bit is set. Otherwise, when the Battery Present bit is zero the Battery Charging Status bits Shall also be zero. Page 198 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6 Alert Message The Alert Message is provided to allow Port Partners to inform each other when there is a status change event. Some of the events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Alert Message Shall only be sent when the Source or Sink detects a status change. The Alert Message Shall contain exactly one Alert Data Object (ADO) and the format Shall be as shown in Figure 6.29, "Alert Message" and Table 6.47, "Alert Data Object (ADO)". Figure 6.29 Alert Message Table 6.47 Alert Data Object (ADO) Bit(s) Field Description B31…24 Type of Alert Bit Description 0 Reserved and Shall be set to zero. 1 Battery Status Change Event Battery Status Change Event (Attach/Detach/charging/discharging/ idle) 2 OCP Event OCP event when set (Source only, for Sink Reserved and Shall be set to zero). 3 OTP Event OTP event when set 4 Operating Condition Change Operating Condition Change when set 5 Source Input Change Event Source Input Change Event when set 6 OVP Event OVP event when set 7 Extended Alert Event Extended Alert Event when set B23…20 Fixed Batteries When Battery Status Change Event bit set indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. B19…16 Hot Swappable Batteries When Battery Status Change Event bit set indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 4 and B19 corresponds to Battery 7. Header No. of Data Objects = 1 ADO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 199 6.4.6.1 Type of Alert The Type of Alert field Shall be used to report Source or Sink status changes. Only one Alert Message Shall be generated for each Event or Change; however multiple Type of Alert bits May be set in one Alert Message. Once the Alert Message has been sent the Type of Alert field Shall be cleared. A Get_Battery_Status Message Should be sent in response to a Battery status change in an Alert Message to get the details of the change. A Get_Status Message Should be sent in response to a non-Battery status change in an Alert Message from to get the details of the change. 6.4.6.1.1 Battery Status Change The Battery Status Change Event bit Shall be set when any Battery's power state changes between charging, discharging, neither. For Hot Swappable Batteries, it Shall also be set when a Battery is Attached or Detached. 6.4.6.1.2 Over-Current Protection Event The OCP Event bit Shall be set when a Source detects its output current exceeds its limits triggering its protection circuitry. This bit is Reserved for a Sink. 6.4.6.1.3 Over-Temperature Protection Event The OTP Event bit Shall be set when a Source or Sink shuts down due to over-temperature triggering its protection circuitry. 6.4.6.1.4 Operating Condition Change The Operating Condition Change bit Shall be set when a Source or Sink detects its Operating Condition enters or exits either the 'warning' or 'over temperature' temperature states. The Operating Condition Change bit Shall be set when the Source operating in the Programmable Power Supply mode detects it has changed its operating condition between Constant Voltage (CV) and Current Limit (CL). 6.4.6.1.5 Source Input Change Event The Source Input Change Event bit Shall be set when the Source/Sink's input changes. For example, when the AC input is removed, and the Source/Sink continues to be powered from one or more of its batteries or when AC returns and the Source/Sink transitions from Battery to AC operation or when the Source/Sink changes operation from one (or more) Battery to another (or more) Battery. B15…4 Reserved Shall be set to zero B3…0 Extended Alert Event Type When the Extended Alert Event bit in the Type of Alert field equals ‘1’, then the Extended Alert Event Type field indicates the event which has occurred:  0 = Reserved.  1 = Power state change (DFP only)  2 = Power button press (UFP only)  3 = Power button release (UFP only)  4 = Controller initiated wake e.g., Wake on LAN (UFP only)  5-15 = Reserved When the Extended Alert Event bit in the Type of Alert field equals ‘0’, then the Extended Alert Event Type field is Reserved and Shall be set to zero. Table 6.47 Alert Data Object (ADO) (Continued) Bit(s) Field Description Page 200 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.6.1.6 Over-Voltage Protection Event The OVP Event bit Shall be set when the Sink detects its output voltage exceeds its limits triggering its protection circuitry. The OVP Event bit May be set when the Source detects its output voltage exceeds its limits triggering its protection circuitry. 6.4.6.1.7 Extended Alert Event The Extended Alert Event bit Shall be set when the event is defined as an Extended Alert Type. 6.4.6.2 Fixed Batteries The Fixed Batteries field indicates which Fixed Batteries have had a status change. B20 corresponds to Battery 0 and B23 corresponds to Battery 3. Once the Alert Message has been sent the Fixed Batteries field Shall be cleared. 6.4.6.3 Hot Swappable Batteries The Hot Swappable Batteries field indicates which Hot Swappable Batteries have had a status change. B16 corresponds to Battery 0 and B19 corresponds to Battery 3. Once the Alert Message has been sent the Hot Swappable Batteries field Shall be cleared. 6.4.6.4 Extended Alert Event Types The Extended Alert Event Type field provides extensions to the available types for the Alert Message. If the Extended Alert Event Type bit is not set, then the Extended Alert Event Type is Reserved and Shall be set to zero. 6.4.6.4.1 Power State Change The Power state change event value May be set when the DFP transitions into a new power state. The new power state Shall be communicated via the Power state change byte in the Status Message. This Message Should be sent by the host in response to any system power state change. 6.4.6.4.2 Power Button Press The Power button press event value May be set when the power button on the UFP is pressed. The press and release events are separated into two different events so that devices that respond differently to a long button press will see a long button press. On the host-side, the power button press event typically initiates the same behavior as a power button press of the host's power button. 6.4.6.4.3 Power Button Release If a Power button press event was sent, then the Power button release event value Shall be sent by the UFP following the Power button press event. If a physical power button press initiated the Power button press event, then the Power button release event Should be sent when the physical button is released. 6.4.6.4.4 Controller Initiated Wake The Controller initiated wake is used to communicate a wake event from the UFP to the DPF such as Wake on LAN from a NIC or another controller. This event doesn't need the press/release form of the Power button press, because it only needs to communicate the presence of the event, and not the timing. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 201 6.4.7 Get_Country_Info Message The Get_Country_Info Message Shall be sent by a Port to get country specific information from its Port Partner using the country's Alpha-2 Country Code defined by [ISO 3166]. The Port Partner responds with a Country_Info Message that contains the country specific information. The Get_Country_Info Message Shall be as shown in Figure 6.30, "Get_Country_Info Message" and Table 6.48, "Country Code Data Object (CCDO)". For example, if the request is for China information, then the Country Code Data Object (CCDO) would be CCDO [31:0] = 434E0000h for "CN" country code. Figure 6.30 Get_Country_Info Message Table 6.48 Country Code Data Object (CCDO) Bit(s) Description B31…24 First character of the Alpha-2 Country Code defined by [ISO 3166] B23…16 Second character of the Alpha-2 Country Code defined by [ISO 3166] B15…0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 CCDO Page 202 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8 Enter_USB Message The Enter_USB Message Shall be sent by the DFP to its UFP Port Partner and to the Cable Plug(s) of an Active Cable, when in an Explicit Contract, to enter a specified USB Mode of operation. The recipient of the Message Shall respond by sending an Accept Message, a Wait Message or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). When entering [USB4] operation, the Enter_USB Message Shall be sent by a [USB4] PDUSB Hub's DFP(s) or [USB4] PDUSB Host's DFP(s) within tEnterUSB:  following a PD Connection.  after a Data Reset to enter [USB4] operation is completed.  after a Data Role Swap is completed. The Enter_USB Message May be sent by a PDUSB Hub's DFP(s) or PDUSB Host's DFP(s) within tEnterUSB following a PD Connection or after a Data Reset to enter [USB 3.2] or [USB 2.0] operation. The Enter_USB Message Shall be used by a PDUSB Hub's DFP(s) to speculatively train the USB links or enter [DPTC2.1] or [TBT3] Alternate Modes prior to the presence of a host. In this case, the Host Present bit Shall be cleared. When the Host is Connected the Enter_USB Message Shall be resent with the Host Present bit set. The Enter_USB Message's Enter USB Data Object (EUDO), received from the Root Hub when the USB Host is connected, Shall be propagated down through the Hub tree. See [USB Type-C 2.4] USB4® Hub Connection Requirements. The Enter_USB Message Shall be as shown in Figure 6.31, "Enter_USB Message" and Table 6.49, "Enter_USB Data Object (EUDO)". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 203 Figure 6.31 Enter_USB Message Table 6.49 Enter_USB Data Object (EUDO) Bit(s) Field Description B31 Reserved Shall be set to zero. B30…28 USB Mode 1  000b:  001b:  010b:  111b…011b: Reserved, Shall Not be used. B27 Reserved Shall be set to zero. B26 USB4 DRD 2  0b: Not capable of operating as a [USB4] Device  1b: Capable of operating as a [USB4] Device B25 USB3 DRD 2  0b: Not capable of operating as a [USB 3.2] Device  1b: Capable of operating as a [USB 3.2] Device B24 Reserved Shall be set to zero. B23…21 Cable Speed 2,3  000b: [USB 2.0]only, no SuperSpeed support  001b: [USB 3.2] Gen1  010b: [USB 3.2]Gen2 and [USB4] Gen2  011b: [USB4] Gen3  100b: [USB4] Gen4  101b…111b: Reserved, Shall Not be used. B20…19 Cable Type 2,3  00b: Passive  01b: Active Re-timer  10b: Active Re-driver  11b: Optically Isolated B18…17 Cable Current 2  00b = VBUS is not supported  01b = Reserved  10b = 3A  11b = 5A B16 PCIe Support 2 [USB4] PCIe tunneling supported by the host B15 DP Support 2 [USB4] DP tunneling supported by the host B14 TBT Support 2 [TBT3] is supported by the host’s USB4® Connection Manager B13 Host Present 2 A Host is present at the top of the USB tree. When this bit is set PCIe Support, DP Support and TBT Support represent the Host’s Capabilities that Shall be propagated down the Hub tree. B12…0 Reserved Shall be set to zero. 1) Entry into [USB 3.2] and [USB4] include entry into [USB 2.0]. 2) Shall be Ignored when received by a Cable Plug (e.g., SOP’ or SOP’’). 3) The DFP Shall interpret the Cable Plug’s reported capability as defined in [USB Type-C 2.4] in the USB4 Discovery and Entry Section. Header No. of Data Objects = 1 EUDO Page 204 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.8.1 USB Mode Field The USB Mode field Shall be used by the DFP to direct the USB Mode the Port Partner is to enter. 6.4.8.2 USB4® DRD Field The USB4 DRD field Shall be set when the Host DFP is capable of operating as a [USB4] Device. A [USB4] Host DFP that sets the USB4 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.3 USB3 DRD Field The USB3 DRD field Shall be set when the Host DFP is capable of operating as a [USB 3.2] Device. A [USB 3.2] Host DFP that sets the USB3 DRD field Shall also be capable of operating as a [USB 2.0] Device. 6.4.8.4 Cable Speed Field The Cable Speed field Shall be used to indicate the cable's maximum speed. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.5 Cable Type Field The Cable Type field Shall be used to indicate whether the cable is passive or active. Further if the cable is active, it indicates the type of active circuits in the cable and if the cable is optically isolated. The value is read from the Cable Plug and interpreted by the DFP as defined by [USB Type-C 2.4] in the USB4 Discovery and Entry Section. 6.4.8.6 Cable Current Field The Cable Current field Shall be used to indicate the cable's current carrying capability. The value is reported by the Cable Plug in the VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field. 6.4.8.7 PCIe Support Field The PCIe Support field Shall be set when the Host DFP is capable of tunneling PCIe over [USB4]. The PCIe Support field May be set speculatively when the Hub's DFP is capable of tunneling PCIe over [USB4]. 6.4.8.8 DP Support Field The DP Support field Shall be set when the Host DFP is capable of tunneling DP over [USB4]. The DP Support field May be set speculatively when the Hub's DFP is capable of tunneling DP over [USB4]. 6.4.8.9 TBT Support Field The TBT Support field Shall be set when the Host DFP is capable of tunneling ThunderboltTM over [USB4] and that the Connection Manager (CM) supports discovery and configuration of Thunderbolt 3 devices connected to the DFP of [USB4] Hubs. The TBT Support field May be set speculatively when the Hub's DFP is capable of tunneling Thunderbolt over [USB4]. 6.4.8.10 Host Present Field The Host Present field Shall be set to indicate that a Host is present upstream. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 205 6.4.9 EPR_Request Message An EPR_Request Message Shall be sent by a Sink, operating in EPR Mode, to request power, typically during the request phase of a power Negotiation. The EPR_Request Message Shall be sent in response to the most recent EPR_Source_Capabilities Message. The EPR_Request Message Shall return a Sink Request Data Object (RDO) that Shall identify the Power Data Object being requested followed by a copy of the Power Data Object being requested. Note: The requested Power Data Object May be either an EPR (A)PDO or SPR (A)PDO. The EPR_Request Message Shall be as shown in Figure 6.32, "EPR_Request Message". Figure 6.32 EPR_Request Message The Source Shall verify the PDO in the EPR_Request Message exactly matches the PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO. The Source Shall respond to an EPR_Request Message in the same manner as it responds to a Request Message with an Accept Message, or a Reject Message (see Section 6.9, "Accept, Reject and Wait"). The Explicit Contract Negotiation process for EPR is the same as the process for SPR Mode except that the Source_Capabilities Message is replaced by the EPR_Source_Capabilities and the Request Message is replaced by the EPR_Request Message. An EPR Source operating in SPR Mode that receives a EPR_Request Message Shall initiate a Hard Reset. The RDO takes a different form depending on the kind of power requested. The PDO and APDO formats are detailed in Section 6.4.2, "Request Message". Header No. of Data Objects = 2 RDO Copy of PDO Page 206 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.10 EPR_Mode Message The EPR_Mode Message is used to enter, acknowledge, and exit the EPR Mode. The Action field is used to describe the action that is to be taken by the recipient of the EPR_Mode Message. The Data field provides additional information for the Message recipient in the EPR Mode Data Object (ERMDO). The EPR_Mode Message Shall be as shown in Figure 6.33, "EPR Mode DO Message" and Table 6.50, "EPR Mode Data Object (EPRMDO)". Figure 6.33 EPR Mode DO Message 6.4.10.1 Process to enter EPR Mode An EPR Source Shall enter EPR Mode upon request by an EPR Sink connected with an EPR Cable when able to offer the Source Capabilities as defined in the Power Rules (See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable"). For Port Partners to successfully enter EPR Mode, the following conditions must be met:  The Sink Shall request entry into the EPR Mode. Table 6.50 EPR Mode Data Object (EPRMDO) Bit(s) Field Description B31…24 Action Value Action Sent By 0x00 Reserved and Shall Not be used. 0x01 Enter Sink only 0x02 Enter Acknowledged Source only 0x03 Enter Succeeded Source only 0x04 Enter Failed Source only 0x05 Exit Sink or Source 0x06…0xFF Reserved and Shall Not be used. B23...16 Data Action Field Data Field Value Enter Shall be set to the EPR Sink Operational PDP Enter Acknowledged Shall be set to zero Enter Succeeded Shall be set to zero Enter Failed Shall be one of the following values:  0x00 - Unknown cause  0x01 - Cable not EPR Capable  0x02 –Source failed to become VCONN Source.  0x03 – EPR Capable bit not set in RDO.  0x04 – Source unable to enter EPR Mode1.  0x05 - EPR Capable bit not set in PDO. All other values are Reserved and Shall Not be used Exit Shall be set to zero B15...0 Reserved Shall be set to zero 1) The Sink May retry entering EPR Mode after receiving this Enter Failed response. Header No. of Data Objects = 1 EPRMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 207  The Source Shall verify the cable is EPR Capable.  A Sink Shall Not be Connected to the Source through a Charge Through VPD (CT-VPD).  The Source and Sink Shall already be in an SPR Explicit Contract.  The EPR Capable bit Shall be set in the Fixed Supply 5V PDO.  The EPR Capable bit Shall have been set in the RDO in the last Request Message received by the Source. To verify the cable is EPR Capable, the EPR Source Shall have already done the following (see Section 6.6.21.4, "tEPRSourceCableDiscovery"):  Discover the cable prior to entering its First Explicit Contract  Alternatively, within tEPRSourceCableDiscovery of entry into the First Explicit Contract  If it is the VCONN Source, discover the cable.  If not the VCONN Source, do a VCONN Swap then discover the cable. and can verify the cable is EPR Capable by completing steps 5 and 6 in the entry process in Figure 6.34, "Illustration of process to enter EPR Mode". The EPR Mode entry process is a Non-interruptible multi-Message AMS. An illustration of this AMS is shown in Figure 6.34, "Illustration of process to enter EPR Mode". Note: Figure 6.34, "Illustration of process to enter EPR Mode" is not Normative but is Informative only. Page 208 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.34 Illustration of process to enter EPR Mode The entry process Shall follow these steps in order: 1) The Sink Shall send the EPR_Mode Message with the Action field set to 1 (Enter) and the Data field set to its Operational PDP. If the EPR Source receives an EPR_Mode Message with the Action field not set to Enter it Shall initiate a Soft Reset. 2) The Source Shall do the following: EPR_Mode Enter #1 Start SPR Mode EPR Mode Sink Source Cable EPR Entry process SPR contract in place #2.a Sink EPR Capable? Abort EPR Entry Send Entry Failed – Sink not EPR Capable #2.b Source EPR Capable? Abort EPR Entry Send Entry Failed – Source not EPR Capable #2.c Source EPR Capable Now? Abort EPR Entry Send Entry Failed – Source unable to enter EPR #2.d Send EPR Ack #3 Received EPR Ack? #4 Known Cable? #7 Send Enter Succeeded N N N N N #5 Is VCONN Source? #8 Received Enter successful? N Error Send Soft Reset #6.a-d EPR Cable? Abort EPR Entry Send Entry Failed – Source not VCONN Source N Y Y Y Y EPR_MODE Enter Succeeded Y Y Y #5 Is VCONN Source? N #5 VCONN Swap N Abort EPR Entry Send Entry Failed – Not EPR Cable Y Y #4 EPR Capable? Y N Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 209 a) Verify the EPR Capable bit was set in the most recent RDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 3 ("EPR Mode Capable bit not set in the RDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. b) Verify the EPR Capable bit was set in the most recent 5V Fixed Supply PDO. If not set, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 5 ("EPR Mode Capable bit not set in the Fixed Supply 5V PDO"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. c) Verify the Source is still able to support EPR Mode. If not, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and Data field set to 4 ("Unable at this time"). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. The Sink May at some time in the future send another request to enter EPR Mode. d) Send an EPR_Mode Message with the Action field set to 2 (Enter Acknowledged). 3) If the Sink receives any Message, other than an EPR_Mode Message with the Action Field set to 2, the Sink Shall initiate a Soft Reset. 4) When the EPR Source has used the Discover Identity Command to determine and remembers the Cable Capabilities or the EPR Source is connected with a captive cable: a) If the cable is EPR Capable it Should go directly to Step 7, but May continue to Step 5. b) If the cable is not EPR Capable it Shall do the following: c) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 1 ("Cable not EPR capable"). d) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 5) If the Source is not the VCONN Source, it Shall send a VCONN_Swap Message a) If the Source fails to become the VCONN Source, it Shall: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field set to 2 (not VCONN Source). ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 6) The Source Shall use the Discover Identity Command to read the cable's e-Marker and verify the following: a) Cable VDO - Maximum VBUS Voltage (Passive Cable)/Maximum VBUS Voltage (Active Cable) field is 11b (50V) b) Cable VDO - VBUS Current Handling Capability (Passive Cable)/VBUS Current Handling Capability (Active Cable) field is 10b (5A) c) Cable VDO - EPR Capable (Passive Cable)/EPR Capable (Active Cable) field is 1b (EPR Capable) d) If the cable fails to respond to the Discover Identity Command or is not EPR Capable, the Source Shall do the following: i) Send an EPR_Mode Message with the Action field set to 4 (Enter Failed) and the Data field to1 ("Cable not EPR capable"). Page 210 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 ii) Abort the EPR Mode entry process and remain in the existing SPR Explicit Contract. 7) The Source Shall send the EPR_Mode Message with the Action field set to 3 (Enter Succeeded) and Shall enter EPR Mode. 8) If the Sink receives an EPR_Mode Message with the Action field set to 3 (Enter Succeeded) it Shall enter EPR Mode, otherwise it Shall initiate a Soft Reset. If the EPR Mode entry process successfully completes within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Source Shall send an EPR_Source_Capabilities Message within tFirstSourceCap. If the EPR Mode entry process has not been aborted or does not complete within tEnterEPR of the last bit of the GoodCRC Message sent in response to the EPR_Mode Message with the Action field set to 1 (Enter), the Sink Shall initiate a Soft Reset. 6.4.10.2 Operation in EPR Mode While operating in EPR Mode, the Source Shall only send EPR_Source_Capabilities Messages to Advertise its power Capabilities and the Sink Shall only respond with EPR_Request Messages to Negotiate Explicit Contracts. The EPR_Request Message May be for either an SPR or EPR (A)PDO. If the Source sends a Source_Capabilities Message, that is not in response to a Sink Get_Source_Cap Message, the Sink Shall initiate a Hard Reset. If the Sink sends a Request Message, the Source Shall initiate a Hard Reset. The Source Shall monitor the CC communications path to ensure that there is periodic traffic. The Sink Shall send an EPR_KeepAlive Message when it has not sent any Messages for more than tSinkEPRKeepAlive to ensure there is timely periodic traffic. If there is no traffic for more than tSourceEPRKeepAlive, the Source Shall initiate a Hard Reset. 6.4.10.3 Exiting EPR Mode 6.4.10.3.1 Commanded Exit While in EPR Mode, either the Source or Sink May exit EPR Mode by sending an EPR_Mode Message with the Action field set to 5 (Exit). The ports Shall be in an Explicit Contract with an SPR (A)PDO prior to the EPR Mode exit process by either:  The Source sending an EPR_Source_Capabilities Message with no EPR (A)PDO s (e.g., only SPR (A)PDO s) or  The Sink negotiating a new Explicit Contract with bit 31 in the RDO set to zero (e.g., only SPR (A)PDO s)). The process to exit EPR Mode is a Non-interruptible multi-Message AMS and Shall follow these steps in order: 1) The Port Partners Shall be in an Explicit Contract with an SPR (A)PDO. 2) Either the Source or Sink Shall send an EPR_Mode Message with the Action field set to 5 (Exit) to exit the EPR Mode 3) The Source Shall send a Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit). 4) If the Sink does not receive a Source_Capabilities Message within tTypeCSinkWaitCap of the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 5 (Exit), Sink Shall initiate a Hard Reset. 6.4.10.3.2 Implicit Exit EPR Mode Shall be exited as the side-effect of the Power Role Swap and Fast Role Swap processes. This is because at the end of these processes VBUS will be at vSafe5V and the Ports will be in an Implicit Contract. The New Source will then send a Source_Capabilities Message (not an EPR_Source_Capabilities Message) to begin the process of Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 211 negotiating an SPR Explicit Contract. Once an SPR Explicit Contract is entered, the Source and Sink can then enter EPR Mode if needed. 6.4.10.3.3 Exits due to errors Other critical errors can occur while in EPR Mode; these errors Shall result in Hard Reset being initiated by the Port that detects the error. Some of these errors include:  An EPR_Mode Message with the Action field set to 5 (Exit) to exit EPR Mode is received by a Port in an Explicit Contract with an EPR (A)PDO.  The Sink receives an EPR_Source_Capabilities Message with an EPR (A)PDO in any of the first seven object positions.  The (A)PDO in the EPR_Request Message does not match the (A)PDO in the latest EPR_Source_Capabilities Message pointed to by the Object Position field in the RDO.  The Source receives a Request Message.  The Sink receives a Source_Capabilities Message not in response to a Get_Source_Cap Message. Page 212 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.11 Source_Info Message The Source_Info Message Shall be sent in response to a Get_Source_Info Message. The Source_Info Message contains one Source Information Data Object (SIDO). The Source_Info Message returns a SIDO whose format Shall be as shown in Figure 6.35, "Source_Info Message" and Table 6.51, "Source_Info Data Object (SIDO)". The Number of Data Objects field in the Source_Info Message Shall be set to 1. The Port Maximum PDP, Port Present PDP, Port Reported PDP and the Port Type are used to identify Capabilities of a Source Port. Figure 6.35 Source_Info Message 6.4.11.1 Port Type Field Port Type is a Static field that Shall be used to indicate whether the amount of power the Port can provide is fixed or can change dynamically. For Ports that are part of a Shared Capacity Group, the Port Type field Shall be set to Managed Capability Port. For Ports not part of a Shared Capacity Group, the Port Type field May be set to either Managed Capability Port or Guaranteed Capability Port. 6.4.11.2 Port Maximum PDP Field Port Maximum PDP is a Static field that Shall report the integer portion of the PDP Rating of the Port. A Guaranteed Capability Port (as indicated by the Port Type field being set to '1') Shall always be capable of supplying this amount of power. A Managed Capability Port (as indicated by the Port Type field being set to '0') Shall be able to offer this amount of power at some time. The Port Maximum PDP Shall be the same as the larger of the SPR Source PDP Rating and the EPR Source PDP Rating in the Source_Capabilities_Extended Message. 6.4.11.3 Port Present PDP Field The Port Present PDP field Shall indicate the integer part of the amount of power the Port is presently capable of supplying including limitations due to Cable Capabilities or abnormal operating conditions (e.g., elevated temperature, low input voltage, etc.). A Guaranteed Capability Port Shall always set its Port Present PDP to be the same as its Port Maximum PDP or the highest possible value when limited. Table 6.51 Source_Info Data Object (SIDO) Bit(s) Field Description B31 Port Type  0 = Managed Capability Port  1 = Guaranteed Capability Port B30…24 Reserved Shall be set to zero B23...16 Port Maximum PDP Power the Port is designed to supply B15…8 Port Present PDP Power the Port is presently capable of supplying B7…0 Port Reported PDP Power the Port is actually advertising Header No. of Data Objects = 1 SIDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 213 A Managed Capability Port that is part of a Shared Capacity Group Shall set its Port Present PDP to Shared Port Power Available as defined in [USB Type-C 2.4] or to a lower value when limited. A Managed Capability Port that is part of an Assured Capacity Group Shall set its Port Present PDP to the Port Maximum PDP or the highest value possible when limited. 6.4.11.4 Port Reported PDP Field The Port Reported PDP field Shall track the amount of power the Port is offering in its Source_Capabilities Message or EPR_Source_Capabilities Message. The Port Reported PDP field May be dynamic or Static depending on the Port's other characteristics such as Managed/Guaranteed Capability, SPR/EPR Mode, its power policy etc. Note: The Port Reported PDP field is computed as the integer part of, the largest of the products of the voltage times current of the Fixed Supply PDOs returned in the Source_Capabilities Message or EPR_Source_Capabilities Messages. Page 214 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.4.12 Revision Message The Revision Message Shall be sent in response to the Get_Revision Message sent by the Port Partner. This Message is used to identify the highest Revision the Port is capable of operating at. The Revision Message contains one Revision Message Data Object (RMDO). The Revision Message returns an RMDO whose format Shall be as shown in Figure 6.36, "Revision Message Data Object"and Table 6.52, "Revision Message Data Object (RMDO)". The Number of Data Objects field in the Revision Message Shall be set to 1. Figure 6.36 Revision Message Data Object E.g., for Revision 3.2, Version 1.1 the fields would be the following:  Revision.major = 0011b  Revision.minor = 0010b  Version.major = 0001b  Version.minor = 0001b Table 6.52 Revision Message Data Object (RMDO) Bit(s) Description B31…28 Revision.major B27…24 Revision.minor B23...20 Version.major B19...16 Version.minor B15...0 Reserved, Shall be set to zero. Header No. of Data Objects = 1 RMDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 215 6.5 Extended Message An Extended Message Shall contain an Extended Message Header (indicated by the Extended field in the Message Header being set) and be followed by zero or more data bytes. Additional bytes that might be added to existing Messages in future Revision of this specification Shall be Ignored. The format of the Extended Message is defined by the Message Header's Message Type field and is summarized in Table 6.53, "Extended Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets and the Messages which May be issued in SOP* Packets. Table 6.53 Extended Message Types Bits 4…0 Type Sent by Description Valid Start of Packet 0 0000 Reserved All values not explicitly defined are Reserved and Shall Not be used. 0 0001 Source_Capabilities_Extended Source or Dual-Role Power See Section 6.5.1 SOP only 0 0010 Status Source, Sink or Cable Plug See Section 6.5.2 SOP* 0 0011 Get_Battery_Cap Source or Sink See Section 6.5.3 SOP only 0 0100 Get_Battery_Status Source or Sink See Section 6.5.4 0 0101 Battery_Capabilities Source or Sink See Section 6.5.5 SOP only 0 0110 Get_Manufacturer_Info Source or Sink See Section 6.5.6 SOP* 0 0111 Manufacturer_Info Source, Sink or Cable Plug See Section 6.5.7 SOP* 0 1000 Security_Request Source or Sink See Section 6.5.8.1 SOP* 0 1001 Security_Response Source, Sink or Cable Plug See Section 6.5.8.2 SOP* 0 1010 Firmware_Update_Request Source or Sink See Section 6.5.9.1 SOP* 0 1011 Firmware_Update_Response Source, Sink or Cable Plug See Section 6.5.9.2 SOP* 0 1100 PPS_Status Source See Section 6.5.10 SOP only 0 1101 Country_Info Source or Sink See Section 6.5.12 SOP only 0 1110 Country_Codes Source or Sink See Section 6.5.11 SOP only 0 1111 Sink_Capabilities_Extended Sink or Dual-Role Power See Section 6.5.13 SOP only 1 0000 Extended_Control Source or Sink See Section 6.5.14 SOP only 1 0001 EPR_Source_Capabilities Source or Dual-Role Power See Section 6.5.15.2 SOP only 1 0010 EPR_Sink_Capabilities Sink or Dual-Role Power See Section 6.5.15.3 SOP only 1 0011... 1 1101 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 1110 Vendor_Defined_Extended Source, Sink or Cable Plug See Section 6.5.16 SOP* 1 1111 Reserved All values not explicitly defined are Reserved and Shall Not be used. Page 216 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1 Source_Capabilities_Extended Message The Source_Capabilities_Extended Message Should be sent in response to a Get_Source_Cap_Extended Message. The Source_Capabilities_Extended Message enables a Source or a DRP to inform the Sink about its Capabilities as a Source. The Source_Capabilities_Extended Message Shall return a 25-byte Source Capabilities Extended Data Block (SCEDB) whose format Shall be as shown in Figure 6.37, "Source_Capabilities_Extended Message" andTable 6.54, "Source Capabilities Extended Data Block (SCEDB)". Figure 6.37 Source_Capabilities_Extended Message Table 6.54 Source Capabilities Extended Data Block (SCEDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 XID Value provided by the USB-IF assigned to the product 8 FW Version Firmware version number 9 HW Version Hardware version number 10 Voltage Regulation Bit Description 1…0  00b: 150mA/µs Load Step (default)  01b: 500mA/µs Load Step  11b…10b: Reserved and Shall Not be used. 2  0b: 25% IoC (default)  1b: 90% IoC 3…7 Reserved and Shall Not be used 11 Holdup Time Output will stay with regulated limits for this number of milliseconds after removal of the AC from the input.  0x00 = feature not supported Note: A value of at least 3ms Should be used (see Section 7.1.12.2, "Holdup Time Field"). 12 Compliance Compliance in SPR Mode: Bit Description 0 LPS compliant when set 1 PS1 compliant when set 2 PS2 compliant when set 3…7 Reserved and Shall Not be used 13 Touch Current Bit Description 0 Low touch current EPS when set 1 Ground pin supported when set 2 Ground pin intended for protective earth when set 3...7 Reserved and Shall Not be used Extended Header Data Size = 25 SCEDB (25-byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 217 6.5.1.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Source's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 14 Peak Current1 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 16 Peak Current2 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 18 Peak Current3 Bit Description 0...4 Percent overload in 10% increments Values higher than 25 (11001b) are clipped to 250%. 5...10 Overload period in 20ms 11...14 Duty cycle in 5% increments 15 VBUS voltage droop 20 Touch Temp Temperature conforms to:  0 = [IEC 60950-1] (default)  1 = [IEC 62368-1] TS1  2 = [IEC 62368-1] TS2 Note: All other values Reserved and Shall Not be used. 21 Source Inputs Bit Description 0  0b: No external supply  1b: External supply present 1 If bit 0 is set:  0b: External supply is constrained.  1b: External supply is unconstrained. If bit 0 is not set Reserved and Shall be set to zero 2  0b: No internal Battery  1b: Internal Battery present 3...7 Reserved and Shall be set to zero 22 Number of Batteries/ Battery Slots Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 23 SPR Source PDP Rating 0…6: Source PDP Rating (EPR Source’s PDP Rating when operating in SPR Mode. 7: Reserved and Shall be set to zero 24 EPR Source PDP Rating 0…7: EPR Source PDP Rating Table 6.54 Source Capabilities Extended Data Block (SCEDB) (Continued) Offset Field Description Page 218 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Source's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.1.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.1.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.1.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.1.6 Voltage Regulation Field The Voltage Regulation field contains bits covering Load Step Slew Rate and Magnitude. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.1.6.1 Load Step Slew Rate The Source Shall report its load step response capability in bits 0…1 of the Voltage Regulation bit field. 6.5.1.6.2 Load Step Magnitude The Source Shall report its load step magnitude rate as a percentage of IoC in bit 2 of the Voltage Regulation field. 6.5.1.7 Holdup Time Field The Holdup Time field Shall contain the Source's holdup time (see Section 7.1.12.2, "Holdup Time Field"). 6.5.1.8 Compliance Field The Compliance is Static and Shall contain the standards the Source is compliant with in SPR (see Section 7.1.12.3, "Compliance Field"). 6.5.1.9 Touch Current Field The Touch Current field reports whether the Source meets certain leakage current levels and if it has a ground pin. A Source Shall set the Touch Current bit (bit 0) when their leakage current is less than 65µA rms when Source's maximum capability is less than or equal to 30W, or when their leakage current is less than 100 µA rms when its power capability is between 30W and 100W. The total combined leakage current Shall be measured in accordance with [IEC 60950-1] when tested at 250VAC rms at 50 Hz. A Source with a ground pin Shall set the Ground pin bit (bit 1). A Source whose Ground pin is intended to be connected to a protective earth Shall set both bit1 and bit 2. 6.5.1.10 Peak Current Field The Peak Current1/Peak Current2/Peak Current3 fields Shall contain the combinations of Peak Current that the Source supports (see Section 7.1.12.4, "Peak Current"). Peak Current provides a means for Source report its ability to provide current in excess of the Negotiated amount for short periods. The Peak Current descriptor defines up to three combinations of% overload, duration and duty Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 219 cycle defined as Peak Current1, Peak Current2 and Peak Current3 that the Source supports. A Source May offer no Peak Current capability. A Source Shall populate unused Peak Current bit fields with zero. The Bit Fields within Peak Current1, Peak Current2 and Peak Current3 contain the following subfields:  Percentage Overload  Shall be the maximum peak current reported in 10% increments as a percentage of the Negotiated operating current (IoC) offered by the Source. Values higher than 25 (11001b) are clipped to 250%.  Overload Period  Shall be the minimum rolling average time window in 20ms increments, where a value of 20ms is recommended.  Duty Cycle  Shall be the maximum percentage of overload period reported in 5% increments. The values Should be 5%, 10% and 50% for PeakCurrent1, PeakCurrent2, and PeakCurrent3, respectively.  VBUS Droop  Shall be set to one to indicate there is an additional 5% voltage droop on VBUS when the overload conditions occur as defined by vSrcPeak. However, it is recommended that the Source Should pro- vide VBUS in the range of vSrcNew when overload conditions occur and set this bit to zero. 6.5.1.11 Touch Temp Field The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Source's enclosure. Safety limits for the Source's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Source May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.1.12 Source Inputs Field The Source Inputs field Shall identify the possible inputs that provide power to the Source:  When bit 0 is set, the Source can be sourced by an external power supply.  When bits 0 and 1 are set, the Source can be sourced by an external power supply which is assumed to be effectively "infinite" i.e., it won't run down over time.  When bit 2 is set the Source can be sourced by an internal Battery. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. Note: Bit 2 May be set independently of bits 0 and 1. 6.5.1.13 Number of Batteries/Battery Slots Field The Number of Batteries/Battery Slots field Shall report the number of Fixed Batteries and Hot Swappable Battery Slots the Source supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. A Source Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 220 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.1.14 SPR Source PDP Rating Field For an SPR Source the SPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an EPR Source, the SPR Source PDP Rating field Shall report the integer portion of the maximum amount of power that the Port is designed to deliver in SPR Mode. The SPR Source PDP Rating field that is reported Shall be Static. 6.5.1.15 EPR Source PDP Rating Field For an EPR Source the EPR Source PDP Rating field Shall report the integer portion of the PDP Rating of the Port. For an SPR Source this field Shall be set to zero. The EPR Source PDP Rating field that is reported Shall be Static. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 221 6.5.2 Status Message The Status Message Shall be sent in response to a Get_Status Message. The content of the Status Message depends on the target of the Get_Status Message. When sent to SOP the Status Message returns the status of the Port's Port Partner. When sent to SOP’ or SOP’’ the Status Message returns the status of one of the Active Cable's Cable Plugs. 6.5.2.1 SOP Status Message A Status Message, sent in response to Get_Status Message to SOP, enables a Port to inform its Port Partner about the present status of the Source or Sink. Typically, a Get_Status Message will be sent by the Port after receipt of an Alert Message. Some of the reported events are critical such as OCP, OVP and OTP, while others are informational such as change in a Battery's status from charging to neither charging nor discharging. The Status Message returns a 7-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.38, "SOP Status Message" and Table 6.55, "SOP Status Data Block (SDB)". Figure 6.38 SOP Status Message Table 6.55 SOP Status Data Block (SDB) Offset (Byte) Field Description 0 Internal Temp Source or Sink’s internal temperature in °C  0 = feature not supported  1 = temperature is less than 2°C.  2-255 = temperature in °C. 1 Present Input Bit Description 0 Reserved and Shall be set to zero 1 External Power when set 2 External Power AC/DC (Valid when Bit 1 set)  0: DC  1: AC Reserved when Bit 1 is zero 3 Internal Power from Battery when set 4 Internal Power from non-Battery power source when set 5...7 Reserved and Shall be set to zero 2 Present Battery Input When Present Input field bit 3 set Shall contain the bit corresponding to the Battery or Batteries providing power:  Upper nibble = Hot Swappable Battery (b7…4)  Lower nibble = Fixed Battery (b3…0) When Present Input field bit 3 is not set this field is Reserved and Shall be set to zero. Extended Header Data Size = 7 SDB (7-byte block) Page 222 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 3 Event Flags Bit Flag Description 0 Reserved and Shall be set to zero 1 OCP Event OCP event when set 2 OTP Event OTP event when set 3 OVP Event OVP event when set 4 CL/CV Mode In PPS Mode only: CL mode when set, CV mode when cleared 5...7 Reserved and Shall be set to zero 4 Temperature Status Bit Description 0 Reserved and Shall be set to zero 1...2  00 – Not Supported.  01 – Normal  10 – Warning  11 – Over temperature 3...7 Reserved and Shall be set to zero 5 Power Status Bit Description 0 Reserved and Shall be set to zero 1 Source power limited due to cable supported current 2 Source power limited due to insufficient power available while sourcing other ports 3 Source power limited due to insufficient external power 4 Source power limited due to Event Flags in place (Event Flags must also be set) 5 Source power limited due to temperature 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 223 6.5.2.1.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of a portion of the Source or Sink. 6.5.2.1.2 Present Input Field The Present Input field indicates which supplies are presently powering the Source or Sink. The following bits are defined:  Bit 1: indicates that an external power source is present.  Bit 2: indicates whether the external unconstrained power source is AC or DC.  Bit 3: indicates that power is being provided from Battery.  Bit4: indicates an alternative internal source of power that is not a Battery. 6.5.2.1.3 Present Battery Input Field The Present Battery Input field indicates which Battery or Batteries are presently supplying power to the Source or Sink. The Present Battery Input field is only Valid when the Present Input field indicates that there is Internal Power from Battery. The upper nibble of the field indicates which Hot Swappable Battery/Batteries are supplying power with bit 4 in upper nibble corresponding to Battery 4 and bit 7 in the upper nibble corresponding to Battery 7 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). The lower nibble of the field indicates which Fixed Battery/Batteries are supplying power with bit 0 in lower nibble corresponding to Battery 0 and bit 3 in the lower nibble corresponding to Battery 3 (see Section 6.5.3, "Get_Battery_Cap Message" and Section 6.5.4, "Get_Battery_Status Message"). 6 Power State Change Bit Description 0...2 New Power State Value Description 0 Status not supported 1 S0 2 Modern Standby 3 S3 4 S4 5 S5 (Off with battery, wake events supported) 6 G3 (Off with no battery, wake events not supported) 7 Reserved and Shall be set to zero 3...5 New Power State indicator Value Description 0 Off LED 1 On LED 2 Blinking LED 3 Breathing LED 4...7 Reserved and Shall be set to zero 6...7 Reserved and Shall be set to zero Table 6.55 SOP Status Data Block (SDB) (Continued) Offset (Byte) Field Description Page 224 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.1.4 Event Flags Field The Event Flags field returns event flags. The OTP, OVP and OCP event flags Shall be set when there is an event and Shall only be cleared when read with the Get_Status Message. When the OTP Event flag is set the Temperature Status field Shall also be set to over temperature. The CL/CV Mode flag is only Valid when operating as a Programmable Power Supply and Shall be Ignored otherwise. When the Source is operating as a Programmable Power Supply the CL/CV Mode flag Shall be set when operating in Current Limit mode (CL) and Shall be cleared when operating in Constant Voltage mode (CV). 6.5.2.1.5 Temperature Status Field The Temperature Status field returns the current temperature status of the device either: normal, warning or over temperature. When the Temperature Status field is set to over temperature the OTP Event flag Shall also be set. 6.5.2.1.6 Power Status Field The Power Status field indicates the current status of a Source. A non-zero return of the field indicates Advertised Source power is being reduced for either:  The cable does not support the full Source current.  The Source is supplying power to other ports and is unable to provide its full power.  The external power to the Source is insufficient to support full power.  An Event has occurred that is causing the Source to reduce its Advertised power. A Sink Shall set this field to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 225 6.5.2.1.7 Power state change The Power State Change field contains two status bytes; the New Power State and New Power State indicator status bytes. 6.5.2.1.7.1 New power state The New Power State status byte indicates a power state change to one of the specified power states. Any device that supports the ACPI standard system power states Shall use the ACPI states. For devices that do not support the ACPI power states, the following mapping Should be used:  High power (on) state -> S0  Sleep state -> S3  Low power (off) state -> S5 or G3 6.5.2.1.7.2 New power state indicator The New Power State indicator status byte defines the host's desired indicator for the specified power state. This indicator allows several possibilities for predefined behaviors that the host can specify to indicate its system power state to the user via the downstream device. The New Power State indicator is a "best effort" indicator. If the device cannot provide the requested indicator, then it provides the best indicator that it can. If a Breathing indicator cannot be provided, then a Blinking indicator Should be provided. If a Blinking indicator cannot be provided, then a constant on indicator Should be provided. New Power State indicators in decreasing precedence:  Breathing  Blinking  Constant on  No indicator Page 226 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.2.2 SOP'/SOP'' Status Message A Status Message, sent in response to a Get_Status Message to SOP’ or SOP’’, enables a Source or Sink to get the present status of the Cable's Cable Plug(s). Typically, a Get_Status Message will be used by the USB Host and/or USB Device to manage the Cable's Cable Plug(s) temperature. The Status Message returns a 2-byte Status Data Block (SDB) whose format Shall be as shown in Figure 6.39, "SOP'/SOP'' Status Message" and Table 6.56, "“SOP’/SOP’’ Status Data Block (SPDB)”". Passive Cable Plugs Shall Not indicate Thermal Shutdown. Figure 6.39 SOP'/SOP'' Status Message 6.5.2.2.1 Internal Temp Field The Internal Temp field reports the instantaneous temperature of the plug in °C. The internal temperature Shall be monotonic. The Cable Plug Shall report its internal temperature every tACTempUpdate. 6.5.2.2.2 Thermal Shutdown Field The Flags flag Shall also be set when the plug's internal temperature exceeds the Internal Maximum Temperature reported in the Active Cable VDO. Once this bit has been set, it Shall remain set and the plug Shall remain in Thermal Shutdown until there is a Hard Reset or the Active Cable's power is removed. The Thermal Shutdown flag Shall Not be cleared by a Cable Reset. Table 6.56 “SOP’/SOP’’ Status Data Block (SPDB)” Offset (Byte) Field Value Description 0 Internal Temp Unsigned Int Cable Plug’s internal temperature in °C.  0 = feature not supported  1 = temperature is less than 2°C.  2…255 = temperature in °C. 1 Flags Bit Field Bit Description 0 Thermal Shutdown 1...7 Reserved and Shall be set to zero Extended Header Data Size = 2 SPDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 227 6.5.3 Get_Battery_Cap Message The Get_Battery_Cap (Get Battery Capabilities) Message is used to request the capability of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Capabilities Message (see Section 6.5.5, "Battery_Capabilities Message") containing a Battery Capabilities Data Block (BCDB) for the targeted Battery. The Get_Battery_Cap Message contains a 1-byte Get Battery Cap Data Block (GBCDB), whose format Shall be as shown in Figure 6.40, "Get_Battery_Cap Message" and Table 6.57, "Get Battery Cap Data Block (GBCDB)". This block defines for which Battery the request is being made. The Data Size field in the Get_Battery_Cap Message Shall be set to 1. Figure 6.40 Get_Battery_Cap Message 6.5.4 Get_Battery_Status Message The Get_Battery_Status (Get Battery Status) Message is used to request the status of a Battery present in its Port Partner. The Port Shall respond by returning a Battery_Status Message (see Section 6.4.5, "Battery_Status Message") containing a Battery Status Data Object (BSDO) for the targeted Battery. The Get_Battery_Status Message contains a 1-byte Get Battery Status Data Block (GBSDB) whose format Shall be as shown in Figure 6.41, "Get_Battery_Status Message" and Table 6.58, "Get Battery Status Data Block (GBSDB)". This block contains details of the requested Battery. The Data Size field in the Get_Battery_Status Message Shall be set to 1. Figure 6.41 Get_Battery_Status Message Table 6.57 Get Battery Cap Data Block (GBCDB) Offset Field Description 0 Battery Cap Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Table 6.58 Get Battery Status Data Block (GBSDB) Offset Field Description 0 Battery Status Ref Number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries.  Values 8…255 are Reserved and Shall Not be used. Extended Header Data Size = 1 GBCDB Extended Header Data Size = 1 GBSDB Page 228 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.5 Battery_Capabilities Message The Battery_Capabilities Message is sent in response to a Get_Battery_Cap Message. The Battery_Capabilities Message contains one Battery Capability Data Block (BCDB) for one of the Batteries its supports as reported by Number of Batteries/Battery Slots field in the Source_Capabilities_Extended Message. The returned BCDB Shall correspond to the Battery requested in the Battery Cap Ref field contained in the Get_Battery_Cap Message. The Battery_Capabilities Message returns a 9-byte BCDB whose format Shall be as shown in Figure 6.42, "Battery_Capabilities Message" and Table 6.59, "Battery Capability Data Block (BCDB)”". Figure 6.42 Battery_Capabilities Message 6.5.5.1 Vendor ID (VID) The VID field Shall contain the manufacturer VID associated with the Battery, as assigned by the USB-IF, or 0xFFFF in the case that no such VID exists. If the Battery Cap Ref field in the Get_Battery_Cap Message is Invalid, the VID field Shall be 0xFFFF. 6.5.5.2 Product ID (PID) The following rules apply to the PID field. When the VID: Table 6.59 Battery Capability Data Block (BCDB)” Offset (Byte) Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Battery Design Capacity Battery’s design capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = design capacity unknown 6 Battery Last Full Charge Capacity Battery’s last full charge capacity in 0.1 WH Note:  0x0000 = Battery not present  0xFFFF = last full charge capacity unknown 8 Battery Type Bit Field Description 0 Invalid Battery Reference Invalid Battery reference when set. 1...7 --- Reserved Extended Header Data Size = 9 BCDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 229  Belongs to the Battery vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  Belongs to the Device vendor the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor.  Is 0xFFFF the PID field Shall be set to 0x0000. 6.5.5.3 Battery Design Capacity Field The Battery Design Capacity field Shall return the Battery's design capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Design Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Design Capacity field Shall be set to 0xFFFF. 6.5.5.4 Battery Last Full Charge Capacity Field The Battery Last Full Charge Capacity field Shall contain the Battery's last full charge capacity in tenths of WH. If the Battery is Hot Swappable and is not present, the Battery Last Full Charge Capacity field Shall be set to zero. If the Battery is unable to report its Design Capacity, the Battery Last Full Charge Capacity field Shall be set to 0xFFFF. 6.5.5.5 Battery Type Field The Battery Type field is used to report additional information about the Battery's Capabilities. 6.5.5.5.1 Invalid Battery Reference The Invalid Battery Reference bit Shall be set when the Get_Battery_Cap Message contains a reference to a Battery that does not exist. Page 230 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.6 Get_Manufacturer_Info Message The Get_Manufacturer_Info (Get Manufacturer Info) Message is sent by a Port to request manufacturer specific information relating to its Port Partner, Cable Plug or of a Battery behind a Port. The Port Shall respond by returning a Manufacturer_Info Message (Section 6.5.7, "Manufacturer_Info Message") containing a Manufacturer Info Data Block (MIDB). Support for this feature by the Cable Plug is Optional Normative. The Get_Manufacturer_Info Message contains a 2-byte Get Manufacturer Info Data Block (GMIDB). This block defines whether it is the Device or Battery manufacturer information being requested and for which Battery the request is being made. The Get_Manufacturer_Info Message returns a GMIDB whose format Shall be as shown in Figure 6.43, "Get_Manufacturer_Info Message" and Table 6.60, "Get Manufacturer Info Data Block (GMIDB)". Figure 6.43 Get_Manufacturer_Info Message Table 6.60 Get Manufacturer Info Data Block (GMIDB) Offset Field Description 0 Manufacturer Info Target  0: Port/Cable Plug  1: Battery  255…2: Reserved and Shall Not be used. 1 Manufacturer Info Ref If the Manufacturer Info Target field is Battery (01b) the Manufacturer Info Ref field Shall contain the Battery number reference which is the number of the Battery indexed from zero:  Values 0…3 represent the Fixed Batteries.  Values 4…7 represent the Hot Swappable Batteries. Otherwise, this field is Reserved and Shall be set to zero. Extended Header Data Size = 2 GMIDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 231 6.5.7 Manufacturer_Info Message The Manufacturer_Info Message Shall be sent in response to a Get_Manufacturer_Info Message. The Manufacturer_Info Message contains the USB VID and the Vendor's PID to identify the device or Battery and the device or Battery's manufacturer byte array in a variable length Data Block of up to MaxExtendedMsgLegacyLen. The Manufacturer_Info Message returns a Manufacturer Info Data Block (MIDB) whose format Shall be as shown in Figure 6.44, "Manufacturer_Info Message" and Table 6.61, "Manufacturer Info Data Block (MIDB)". Figure 6.44 Manufacturer_Info Message 6.5.7.1 Vendor ID (VID) If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the VID field Shall contain:  The manufacturer's VID associated with the Port/Cable Plug, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Device that has a USB data interface, the Device Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery, the VID field Shall contain:  The manufacturer VID associated with the Battery specified, as defined by the USB-IF, or  0xFFFF in the case that the vendor does not have a VID. If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message:  Is Invalid, this VID field Shall be 0xFFFF.  Is Battery (01b) and the Manufacturer Info Ref field is Invalid, the VID field Shall be 0xFFFF. 6.5.7.2 Product ID (PID) If the VID is 0xFFFF, the PID field Shall contain 0x0000. Otherwise: Table 6.61 Manufacturer Info Data Block (MIDB) Offset Field Description 0 VID Vendor ID (assigned by the USB-IF) 2 PID Product ID (assigned by the manufacturer) 4 Manufacturer String Vendor defined null terminated string of 0…21 characters. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string “Not Supported”. Extended Header Data Size = 5..26 MIDB Page 232 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with this Port/Cable Plug, the PID field Shall contain the device's 16-bit product identifier designated by the device vendor.  If the in Manufacturer Info Target field in the Get_Manufacturer_Info Message is associated with a Battery:  And the VID belongs to the Battery vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Battery vendor.  And the VID belongs to the Device vendor, the PID field Shall contain the Battery's 16-bit product identifier designated by the Device vendor. 6.5.7.3 Manufacturer String The Manufacturer String field Shall contain the device’s or Battery's manufacturer string as defined by the vendor. If the Manufacturer Info Target field or Manufacturer Info Ref field in the Get_Manufacturer_Info Message is unrecognized the field Shall return a null terminated ASCII text string "Not Supported". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 233 6.5.8 Security Messages The authentication process between Port Partners or a Port and Cable Plug is fully described in [USBTypeCAuthentication 1.0]. This specification describes two Extended Messages used by the authentication process when applied to PD. In the authentication process described in [USBTypeCAuthentication 1.0] there are three basic exchanges that serve to:  Get the Port or Cable Plug's certificates.  Get the Port or Cable Plug's digest.  Challenge the Port Partner or Cable Plug. Certificates are used to convey information, attested to by a signer, which attests to the Port Partner's or Cable Plug's authenticity. The Port's or Cable Plug's certificates are needed when a Port encounters a Port Partner or Cable Plug it has not been Attached to before. To minimize calculations after the initial Attachment, a Port can also use a digest consisting of hashes of the certificates rather than the certificates themselves. Once the Port has the certificates and has calculated the hashes, it stores the hashes and uses the digest in future exchanges. After the Port gets the certificates or digest, it challenges its Port Partner or the Cable Plug to detect replay attacks. For further details refer to [USBTypeCAuthentication 1.0]. 6.5.8.1 Security_Request The Security_Request Message is used by a Port to pass a security data structure to its Port Partner or a Cable Plug. The Security_Request Message contains a Security Request Data Block (SRQDB) whose format Shall be as shown in Figure 6.45, "Security_Request Message". The contents of the SRQDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.45 Security_Request Message 6.5.8.2 Security_Response The Security_Response Message is used by a Port or Cable Plug to pass a security data structure to the Port that sent the Security_Request Message. The Security_Response Message contains a Security Response Data Block (SRPDB) whose format Shall be as shown in Figure 6.46, "Security_Response Message". The contents of the SRPDB and its use are defined in [USBTypeCAuthentication 1.0]. Figure 6.46 Security_Response Message Extended Header Data Size = 4..260 SRQDB Extended Header Data Size = 4..260 SRPDB Page 234 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.9 Firmware Update Messages The firmware update process between Port Partners or a Port and Cable Plug is fully described in [USBPDFirmwareUpdate 1.0]. This specification describes two Extended Messages used by the firmware update process when applied to PD. 6.5.9.1 Firmware_Update_Request The Firmware_Update_Request Message is used by a Port to pass a firmware update data structure to its Port Partner or a Cable Plug. The Firmware_Update_Request Message contains a Firmware Update Request Data Block (FRQDB) whose format Shall be as shown in Figure 6.47, "Firmware_Update_Request Message". The contents of the FRQDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.47 Firmware_Update_Request Message 6.5.9.2 Firmware_Update_Response The Firmware_Update_Response Message is used by a Port or Cable Plug to pass a firmware update data structure to the Port that sent the Firmware_Update_Request Message. The Firmware_Update_Response Message contains a Firmware Update Response Data Block (FRPDB) whose format Shall be as shown in Figure 6.48, "Firmware_Update_Response Message". The contents of the FRPDB and its use are defined in [USBPDFirmwareUpdate 1.0]. Figure 6.48 Firmware_Update_Response Message Extended Header Data Size = 4..260 FRQDB Extended Header Data Size = 4..260 FRPDB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 235 6.5.10 PPS_Status Message The PPS_Status Message Shall be sent in response to a Get_PPS_Status Message. The PPS_Status Message enables a Sink to query the Source to get additional information about its operational state. The Get_PPS_Status Message and the PPS_Status Message Shall only be supported when the Alert Message is also supported. The PPS_Status Message Shall return a 4-byte PPS Status Data Block (PPSSDB) whose format Shall be as shown in Figure 6.49, "PPS_Status Message" and Table 6.62, "PPS Status Data Block (PPSSDB)". Figure 6.49 PPS_Status Message 6.5.10.1 Output Voltage Field The Output Voltage field Shall return the Source's output voltage at the time of the request. The output voltage is measured either at the Source's receptacle or, if the Source has a captive cable, where the voltage is applied to the cable. The measurement accuracy Shall be +/-3% rounded to the nearest 20mV in SPR PPS Mode. If the Source does not support the Output Voltage field, the field Shall be set to 0xFFFF. 6.5.10.2 Output Current Field The Output Current field Shall return the Source's output current at the time of the request measured at the Source's receptacle. The measurement accuracy Shall be +/-150mA. If the Source does not support the Output Current field, the field Shall be set to 0xFF. Table 6.62 PPS Status Data Block (PPSSDB) Offset (Byte) Field Description 0 Output Voltage 2 Source’s output voltage in 20mV units. When set to 0xFFFF, the Source does not support this field. 2 Output Current 1 Source’s output current in 50mA units. When set to 0xFF, the Source does not support this field. 3 Real Time Flags Bit Description 0 Reserved and Shall be set to zero 1...2 PTF  PTF: 00 – Not Supported  PTF: 01 – Normal  PTF: 10 – Warning  PTF: 11 – Over temperature 3 OMF OMF (Operating Mode Flag) is set when operating in Current Limit mode and cleared when operating in Constant Voltage mode. 4...7 Reserved and Shall be set to zero Extended Header Data Size = 4 PPSSDB (4-byte Data Block) Page 236 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.10.3 Real Time Flags Field Real Time flags provide a real-time indication of the Source's operating state:  The PTF (Present Temperature Flag) Shall provide a real-time indication of the Source's internal thermal status. If the PTF is not supported, it will be set to zero:  Normal indicates that the Source is operating within its normal thermal envelope.  Warning indicates that the Source is over-heating but is not in imminent danger of shutting down.  Over Temperature indicates that the Source is over heated and will shut down soon or has already shutdown and has sent the OTP Event flag in an Alert Message.  The OMF (Operating Mode Flag) Shall provide a real-time indication of the SPR PPS Source's operating mode. When set, the Source is operating in Current Limit mode; when cleared it is operating Constant Voltage mode. This bit Shall be set to zero when not in SPR PPS Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 237 6.5.11 Country_Codes Message The Country_Codes Message Shall be sent in response to a Get_Country_Codes Message. The Country_Codes Message enables a Port to query its Port Partner to get a list of alpha-2 country codes as defined in [ISO 3166] for which the Port Partner has country specific information. The Country_Codes Message Shall contain a 4…26-byte Country Code Data Block (CCDB) whose format Shall be as shown in Figure 6.50, "Country_Codes Message" and Table 6.63, "Country Codes Data Block (CCDB)". Figure 6.50 Country_Codes Message 6.5.11.1 Country Code Field The Country Code field Shall contain Length Country Codes in the Alpha-2 Country Code defined by [ISO 3166]. Table 6.63 Country Codes Data Block (CCDB) Offset Field Description 0 Length Number of country codes in the Message 1 Reserved Shall be set to zero. 2... Length * 2n Country Code Offset Field Description 2 1st Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 3 Second character of the Alpha-2 Country Code defined by [ISO 3166] 4 2nd Country Code First character of the Alpha-2 Country Code defined by [ISO 3166] 5 Second character of the Alpha-2 Country Code defined by [ISO 3166] … Length * 2n nth Country Code Extended Header Data Size = 4-26 CCDB (4-26 byte Data Block) Page 238 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.12 Country_Info Message The Country_Info Message Shall be sent in response to a Get_Country_Info Message. The Country_Info Message enables a Port to get additional country specific information from its Port Partner. The Country_Info Message Shall contain a 4…26-byte Country Info Data Block (CIDB) whose format Shall be as shown in Figure 6.51, "Country_Info Message" and Table 6.64, "Country Info Data Block (CIDB)". Figure 6.51 Country_Info Message 6.5.12.1 Country Code Field The Country Code field Shall contain the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 6.5.12.2 Country Specific Data Field The Country Specific Data field Shall contain content defined by and formatted in a manner determined by an official agency of the country indicated in the Country Code field. If the Country Code field in the Get_Country_Info Message is unrecognized then Country Specific Data field Shall return the null terminated ASCII text string "Unsupported Code". Table 6.64 Country Info Data Block (CIDB) Offset Field Size 0 Country Code First character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message. 1 Second character of the Alpha-2 Country Code received in the corresponding Get_Country_Info Message 2…3 Reserved Shall be set to zero. 4 Country Specific Data 1…22 bytes of content defined by the country’s authority. Extended Header Data Size = 4-26 CIDB (4-26 byte Data Block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 239 6.5.13 Sink_Capabilities_Extended Message The Sink_Capabilities_Extended Message Shall be sent in response to a Get_Sink_Cap_Extended Message. The Sink_Capabilities_Extended Message enables a Sink or a DRP to inform the Source about its Capabilities as a Sink. The Sink_Capabilities_Extended Message Shall return a 24-byte Sink Capabilities Extended Data Block (SKEDB) whose format Shall be as shown in Figure 6.52, "Sink_Capabilities_Extended Message" and Table 6.65, "Sink Capabilities Extended Data Block (SKEDB)". Figure 6.52 Sink_Capabilities_Extended Message Table 6.65 Sink Capabilities Extended Data Block (SKEDB) Offset (Byte) Field Size (Bytes) Type Description 0 VID 2 Numeric Vendor ID (assigned by the USB-IF) 2 PID 2 Numeric Product ID (assigned by the manufacturer) 4 XID 4 Numeric Value provided by the USB-IF assigned to the product 8 FW Version 1 Numeric Firmware version number 9 HW Version 1 Numeric Hardware version number 10 SKEDB Version 1 Numeric SKEDB Version (not the specification Version):  Version 1.0 = 1 Values 0 and 2-255 are Reserved and Shall Not be used. 11 Load Step 1 Bit Field Bit Description 0...1  00b: 150mA/μs Load Step (default)  01b: 500mA/μs Load Step 11b…10b: Reserved and Shall Not be used. 2...7 Reserved and Shall be set to zero 12 Sink Load Characteristics 2 Bit Field Bit Description 0...4 Percent overload in 10% increments. Values higher than 25 (11001b) are clipped to 250%. 00000b is the default. 5...10 Overload period in 20ms when bits 0...4 non-zero. 1...14 Duty cycle in 5% increments when bits 0...4 are non-zero. 15 Can tolerate VBUS voltage droop 14 Compliance 1 Bit Field Bit Description 0 Requires LPS Source when set 1 Requires PS1 Source when set 2 Requires PS2 Source when set 3...7 Reserved and Shall be set to zero Extended Header Data Size = 24 SKEDB (24 byte Data Block) Page 240 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.1 Vendor ID (VID) Field The VID field Shall contain the 16-bit Vendor ID (VID) assigned to the Sink's vendor by the USB-IF. If the vendor does not have a VID, the VID field Shall be set to 0xFFFF. Devices that have a USB data interface Shall report the same VID as the idVendor in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 6.5.13.2 Product ID (PID) Field The PID field Shall contain the 16-bit Product ID (PID) assigned by the Sink's vendor. Devices that have a USB data interface Shall report the same PID as the idProduct in the Standard Device Descriptor (see [USB 2.0] and [USB 3.2]). 15 Touch Temp 1 Value Temperature conforms to:  0 = Not applicable  1 = [IEC 60950-1] (default)  2 = [IEC 62368-1] TS1  3 = [IEC 62368-1] TS2 Note: All other values Reserved 16 Battery Info 1 Byte Upper Nibble = Number of Hot Swappable Battery Slots (0…4) Lower Nibble = Number of Fixed Batteries (0…4) 17 Sink Modes 1 Bit Field Bit Description 0 PPS charging supported 1 VBUS powered 2 AC Supply powered 3 Battery powered 4 Battery essentially unlimited 5 AVS Support 6...7 Reserved and Shall be set to zero 18 SPR Sink Minimum PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 7 Reserved and Shall be set to zero 19 SPR Sink Operational PDP 1 Byte Bit Description 0...6 The PDP of the Source that the Sink requires to operate at its normal functionality. 7 Reserved and Shall be set to zero 20 SPR Sink Maximum PDP 1 Byte Bit Description 0...6 The maximum PDP the Sink will ever request. 7 Reserved and Shall be set to zero 21 EPR Sink Minimum PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its lowest functionality without consuming power from its Battery if it has one. 22 EPR Sink Operational PDP 1 Byte The PDP of the Source that the EPR Sink requires to operate at its normal functionality. 23 EPR Sink Maximum PDP 1 Byte The maximum PDP that the EPR Sink will ever request. Table 6.65 Sink Capabilities Extended Data Block (SKEDB) (Continued) Offset (Byte) Field Size (Bytes) Type Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 241 6.5.13.3 XID Field The XID field Shall contain the 32-bit XID provided by the USB-IF to the vendor who in turns assigns it to a product. If the vendor does not have an XID, then it Shall return zero in this field (see [USB 2.0] and [USB 3.2]). 6.5.13.4 Firmware Version Field The FW Version field Shall contain an 8-bit firmware version number assigned to the device by the vendor. 6.5.13.5 Hardware Version Field The HW Version field Shall contain an 8-bit hardware version number assigned to the device by the vendor. 6.5.13.6 SKEDB Version Field The SKEDB Version field contains the version level of the SKEDB. Currently only Version 1 is defined. 6.5.13.7 Load Step Field The Load Step field contains bits indicating the Load Step Slew Rate and Magnitude that this Sink prefers. See Section 7.1.12.1, "Voltage Regulation Field" for further details. 6.5.13.8 Sink Load Characteristics Field The Sink Shall report its preferred load characteristics in the Sink Load Characteristics field. Regardless of this value, in operation its load Shall Not exceed the Capabilities reported in the Source_Capabilities_Extended Message. 6.5.13.9 Compliance Field The Compliance field Shall contain the types of Sources the Sink has been tested and certified with (see Section 7.1.12.3, "Compliance Field"). 6.5.13.10 Touch Temp The Touch Temp field Shall report the IEC standard used to determine the surface temperature of the Sink's enclosure. Safety limits for the Sink's touch temperature are set in applicable product safety standards (e.g., [IEC 60950-1] or [IEC 62368-1]). The Sink May report when its touch temperature performance conforms to the TS1 or TS2 limits described in [IEC 62368-1]. 6.5.13.11 Battery Info The Battery Info field Shall report the number of Fixed Batteries and Hot Swappable Battery slots the Sink supports. This field Shall independently report the number of Battery Slots and the number of Fixed Batteries. The information reported in the Battery Info field Shall match that reported in the Number of Batteries/Battery Slots field of the Source_Capabilities_Extended Message. A Sink Shall have no more than 4 Fixed Batteries and no more than 4 Battery Slots. Fixed Batteries Shall be numbered consecutively from 0 to 3. The number assigned to a given Fixed Battery Shall Not change between Attach and Detach. Battery Slots Shall be numbered consecutively from 4 to 7. The number assigned to a given Battery Slot Shall Not change between Attach and Detach. Page 242 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.13.12 Sink Modes The Sink Modes bit field Shall identify the charging Capabilities and the power sources that can be used by the Sink. When bit 0 is set, the Sink has the ability to use a PPS Source for fast charging. The source of power a Sink can use:  When bit 1 is set, the Sink has the ability to be sourced by VBUS.  When bit 2 is set, the Sink has the ability to be sourced by an AC Supply.  When bit 3 is set, the Sink has the ability to be sourced by a Battery.  When bit 4 is set, the Sink has the ability to be sourced by a Battery with essentially infinite energy (e.g., a car battery). Bits 1-4 May be set independently of one another. The combination indicates what sources of power the Sink can utilize. For example, some Sinks are only powered by a Battery (e.g., an automobile battery) rather than the more common AC Supply and some Sinks are only powered from VBUS or VCONN. When bit 5 is set, the Sink has the ability to support AVS. 6.5.13.13 SPR Sink Minimum PDP The SPR Sink Minimum PDP field Shall contain the minimum power Source PDP needed by the Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The SPR Sink Minimum PDP field Shall be less than or equal to the SPR Sink Operational PDP. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of SPR Sink Minimum PDP could be:  The minimum power a wireless Charger would require in order to detect, and deliver the minimum required amount of power to the attached device.  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device 6.5.13.14 SPR Sink Operational PDP The SPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The SPR Sink Operational PDP field Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), the SPR Sink Operational PDP field Shall correspond to the PDP Rating of the Charger shipped with the Sink or the recommended Charger's PDP Rating. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set the SPR Sink Minimum PDP field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. The SPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 243 6.5.13.15 SPR Sink Maximum PDP The SPR Sink Maximum PDP field Shall contain the highest PDP the Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The SPR Sink Maximum PDP field Shall Not be less than the SPR Sink Operational PDP field, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is EPR Capable and is unable to operate at PDPs less than 100W, it Shall set this field to the minimum power to sustain PD communication. If the Sink is self-powered, such that it doesn't need power from a Source, then it Shall set this field to zero. 6.5.13.16 EPR Sink Minimum PDP The EPR Sink Minimum PDP field Shall contain the Source PDP needed by an EPR Sink, rounded up to the next integer, to operate at its lowest level of functionality without requiring power from its Battery, if present. Battery charging may be an opportunistic feature, however this PDP Should be designed for basic functionality, not for charging. The EPR Sink Minimum PDP field Shall be less than or equal to the EPR Sink Operational PDP field value. The value is used by the Source to determine whether or not it has sufficient power to minimally support the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Minimum PDP is used to indicate to Shared Capacity Chargers the power that Should be delivered to the Sink to guarantee at least basic functionality for the end user. Possible examples of EPR Sink Minimum PDP could be:  The power required to have basic functionality by a Batteryless Sink,  On a device with a Battery, it can power the minimum functionality of the device. Note: EPR Sink Minimum PDP can be the same as its SPR Sink Minimum PDP. 6.5.13.17 EPR Sink Operational PDP The EPR Sink Operational PDP field Shall contain the Source PDP that the manufacturer recommends for the normal functionality of the Sink, rounded up to the next integer. This corresponds to the PDP Rating of EPR Sources that the Sink is designed to operate with (See Section 10.3.2, "Normative Sink Rules"). The EPR Sink Operational PDP Shall be sufficient to operate all the Sink's functional modes normally AND charge the Sink's Battery if present. For Sinks with a Battery(s), it Shall correspond to the PDP Rating of the Charger shipped with the EPR Sink or the recommended Charger's PDP Rating. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. The EPR Sink Operational PDP is used to indicate to Shared Capacity Chargers that at this power level the user is not expected to receive any performance warning related to the power being supplied to the Sink. 6.5.13.18 EPR Sink Maximum PDP The EPR Sink Maximum PDP field Shall be highest PDP the EPR Sink will ever request under any operating condition, rounded up to the next integer, including charging its Battery if present. The EPR Sink Maximum PDP field Shall Not be less than the EPR Sink Operational PDP, but May be the same. The value is used by the Source to determine the maximum amount of power it has to budget for the Attached Sink. If the Sink is not EPR Capable, or if the Sink is self-powered, such that it doesn't need power from a Source, this field Shall be set to zero. Page 244 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.14 Extended_Control Message The Extended_Control Message extends the Control Message space. The Extended_Control Message includes one byte of data. The Extended_Control Message Shall be as shown in Figure 6.53, "Extended_Control Message" and Table 6.66, "Extended Control Data Block (ECDB)". Figure 6.53 Extended_Control Message The Extended_Control Message types are specified in the Type field of the ECDB and are listed in Table 6.67, "Extended Control Message Types". The Sent by column indicates entities which May send the given Message (Source, Sink or Cable Plug); entities not listed Shall Not issue the corresponding Message. The "Valid Start of Packet" column indicates the Messages which Shall only be issued in SOP Packets. 6.5.14.1 EPR_Get_Source_Cap Message The EPR_Get_Source_Cap (EPR Get Source Capabilities) Message Shall only be sent by a Port capable of operating as a Sink and that supports EPR Mode to request the Source Capabilities and Dual-Role Power capability of its Port Partner. A Port that can operate as an EPR Source Shall respond by returning an EPR_Source_Capabilities Message (see Section 6.5.15.2, "EPR_Source_Capabilities Message"). A Port that does not support EPR Mode as a Source Shall return the Not_Supported Message. An EPR Capable Sink Port that is operating in SPR Mode Shall treat the EPR_Source_Capabilities Message as informational only and Shall Not respond with an EPR_Request Message. 6.5.14.2 EPR_Get_Sink_Cap Message The EPR_Get_Sink_Cap (EPR Get Sink Capabilities) Message Shall only be sent by a Port capable of operating as a Source and that supports EPR Mode to request the Sink Capabilities and Dual-Role Power capability of its Port Partner. A Port that is EPR Capable operating as a Sink Shall respond by returning an EPR_Sink_Capabilities Message (see Section 6.5.15.3, "EPR_Sink_Capabilities Message"). A Port that does not support EPR Mode as a Sink Shall return the Not_Supported Message. Table 6.66 Extended Control Data Block (ECDB) Offset Field Value Description 0 Type Unsigned Int Extended Control Message Type 1 Data Byte Shall be set to zero when not used. Table 6.67 Extended Control Message Types Type Data Message Type Sent by Description Valid Start of Packet 0 Reserved All values not explicitly defined are Reserved and Shall Not be used. 1 Not used EPR_Get_Source_Cap Sink or DRP See Section 6.5.14.1 SOP only 2 Not used EPR_Get_Sink_Cap Source or DRP See Section 6.5.14.2 SOP only 3 Not used EPR_KeepAlive Sink See Section 6.5.14.3 SOP only 4 Not Used EPR_KeepAlive_Ack Source See Section 6.5.14.4 SOP only 5...255 Reserved All values not explicitly defined are Reserved and Shall Not be used. Extended Header Data Size = 2 ECDB (2-byte block) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 245 6.5.14.3 EPR_KeepAlive Message The EPR_KeepAlive Message May be sent by a Sink operating in EPR Mode to meet the requirement for periodic traffic. The Source operating on EPR Mode responds by returning an EPR_KeepAlive_Ack Message to the Sink. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.14.4 EPR_KeepAlive_Ack Message The EPR_KeepAlive_Ack Message Shall be sent by a Source operating in EPR Mode in response to an EPR_KeepAlive Message. See Section 6.4.9, "EPR_Request Message" for additional information. 6.5.15 EPR Capabilities Message The EPR Capabilities Message is an Extended Capabilities Message made of Power Data Objects (PDO) defined in Section 6.4.1, "Capabilities Message". It is used to form EPR_Source_Capabilities Messages and EPR_Sink_Capabilities Messages. Sources expose their EPR power Capabilities by sending an EPR_Source_Capabilities Message. Sinks expose their EPR power requirements by returning an EPR_Sink_Capabilities Message when requested. Both are composed of a number of 32-bit Power Data Objects (see Table 6.7, "Power Data Object"). An EPR Capabilities Message Shall have a 5V Fixed Supply PDO containing the sending Port's information in the first object position followed by up to 10 additional PDOs. 6.5.15.1 EPR Capabilities Message Construction The EPR Capabilities Messages (EPR_Source_Capabilities and EPR_Sink_Capabilities) are Extended Messages with the first seven positions filled with the same SPR (A)PDOs returned by the SPR Capabilities Messages (Source_Capabilities and Sink_Capabilities) followed by the EPR (A)PDOs starting in the eighth position. See Figure 6.54, "Mapping SPR Capabilities to EPR Capabilities". Figure 6.54 Mapping SPR Capabilities to EPR Capabilities Power Data Objects in the EPR Capabilities Messages Shall be sent in the following order: 1) The SPR (A)PDOs as reported in the SPR Capabilities Message. The Number of Data Objects field in the Message Header of the EPR Capabilities Message is the same as the Number of Data Objects field in the Message Header of the SPR Capabilities Message. 2) If the SPR Capabilities Message contains fewer than 7 PDOs, the unused Data Objects Shall be zero filled. 3) The EPR (A)PDOs as defined in Section 6.4.1, "Capabilities Message" Shall start at Data Object position 8 and Shall be sent in the following order: a) Fixed Supply PDOs that offer 28V, 36V or 48V, if present, Shall be sent in voltage order; lowest to highest. b) One EPR AVS APDO Shall be sent. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 EPR PDO 8 EPR PDO 9 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 PDOs > 20V2 001b 010b 011b 100b 101b 110b 111b 1000b 1001b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b EPR PDO 10 EPR PDO 11 1010b 1011b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. 2) See Section 10 “Power Rules” for rules, on which EPR (A)PDOs are allowed be used for a given PDP. Page 246 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.5.15.2 EPR_Source_Capabilities Message The EPR_Source_Capabilities is an EPR Capabilities Message containing a list of Power Data Objects that the EPR Source is capable of supplying. It is sent by an EPR Source in order to convey its Capabilities to a Sink. An EPR Source Shall send the EPR_Source_Capabilities Message:  When entering EPR Mode  While in EPR Modes when its Capabilities change  In response to an EPR_Get_Source_Cap Message  After a Soft Reset while in EPR Mode An EPR Sink operating in EPR Mode Shall evaluate every EPR_Source_Capabilities Message it receives and Shall respond with a EPR_Request Message. If its power consumption exceeds the Source Capabilities, it Shall Re- negotiate so as not to exceed the Source's most recently Advertised Source Capabilities. While operating in SPR Mode, an EPR Sink receiving an EPR_Source_Capabilities Message in response to an EPR_Get_Source_Cap Messages Shall Not respond with an EPR_Request Message. The (A)PDOs in an EPR_Source_Capabilities Message Shall only be requested using the EPR_Request Message and only when in EPR Mode. When Source wants to exit EPR Mode, if not already in power contract with an SPR (A)PDO, it Shall send an EPR_Source_Capabilities Message with no EPR (A)PDOs (i.e. seven SPR (A)PDOs including any zero padded ones). See Figure 6.55, "EPR_Source_Capabilities message with no EPR PDOs". Figure 6.55 EPR_Source_Capabilities message with no EPR PDOs 6.5.15.3 EPR_Sink_Capabilities Message The EPR_Sink_Capabilities is an EPR Capabilities Message that contains a list of Power Data Objects that the EPR Sink requires to operate. It is sent by an EPR Sink in order to convey its power requirements to an EPR Source. The EPR Sink Shall only send the EPR_Sink_Capabilities Message in response to an EPR_Get_Sink_Cap Message. Header 2 bytes Extended Header 4 bytes SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 SPR PDO 1 SPR PDO 2 SPR PDO 3 SPR PDO 4 SPR PDO 5 SPR PDO 6 SPR PDO 7 001b 010b 011b 100b 101b 110b 111b Capabilities EPR Capabilities 001b 010b 011b 100b 101b 110b 111b PDOs 20V1 1) See Section 10 “Power Rules” for rules, on which SPR (A)PDOs are allowed to be used for a given PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 247 6.5.16 Vendor_Defined_Extended Message The Vendor_Defined_Extended Message (VDEM) is provided to allow vendors to exchange information outside of that defined by this specification using the Extended Message format. A Vendor_Defined_Extended Message Shall consist of at least one Vendor Data Object, the VDM Header, and May contain up to a maximum of 256 additional data bytes. To ensure vendor uniqueness of Vendor_Defined_Extended Messages, all Vendor_Defined_Extended Messages Shall contain a Valid USB Standard or Vendor ID (SVID) allocated by USB-IF in the VDM Header. A VDEM does not define any structure and Messages May be created in any manner that the vendor chooses. Vendor_Defined_Extended Messages Shall Not be used for direct power Negotiation. They May however be used to alter Local Policy, affecting what is offered or consumed via the normal PD Messages. For example, a Vendor_Defined_Extended Message could be used to enable the Source to offer additional power via a Source_Capabilities Message. Vendor_Defined_Extended Messages Shall Not be used where equivalent functionality is contained in the PD Specification e.g., authentication or firmware update. The Message format Shall be as shown in Figure 6.56, "Vendor_Defined_Extended Message". Figure 6.56 Vendor_Defined_Extended Message The VDM Header Shall be the first 4-bytes in a Vendor Defined Extended Message. The VDM Header provides Command space to allow vendors to customize Messages for their own purposes. The VDM Header in the VDEM Shall follow the Unstructured VDM Header format as defined in Section 6.4.4.1, "Unstructured VDM". VDEMs Shall only be sent and received after an Explicit Contract has been established. A VDEM AMS Shall Not interrupt any other PD AMS. The VDEM does not define the contents of bits B14…0 in the VDM Header. Their definition and use are the sole responsibility of the vendor indicated by the SVID. The Port Partners and Cable Plugs Shall exit any states entered using a VDEM according to the rules defined in Section 6.4.4.3.4, "Enter Mode Command". The following rules apply to the use of VDEM Messages:  VDEMs Shall Not be initiated or responded to under any other circumstances than the following:  VDEMs Shall only be used when an Explicit Contract is in place.  Prior to establishing an Explicit Contract VDEMs Shall Not be sent and Shall be Ignored if received.  Cable Plugs Shall Not initiate VDEMs. Extended Header Data Size = 4...260 VDM Header VDEDB (0...256-byte Data Block) Page 248 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  VDEMs Shall only be used during Modal Operation in the context of an Active Mode i.e., only after the UFP has Ack'ed the Enter Mode Command can VDEMs be sent or received. The Active Mode and the associated VDEMs Shall use the same SVID.  VDEMs May be used with SOP* Packets.  When a DFP or UFP does not support VDEMs or does not recognize the VID it Shall return a Not_Supported Message. Note: Usage of VDEMs with Chunking is not recommended since this is less efficient than using Unstructured VDMs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 249 6.6 Timers All the following timers are defined in terms of bits on the bus regardless of where they are implemented in terms of the logical architecture. This is to ensure a fixed reference for the starting and stopping of timers. It is left to the implementer to ensure that this timing is observed in a real system. 6.6.1 CRCReceiveTimer The CRCReceiveTimer Shall be used by the sender's Protocol Layer to ensure that a Message has not been lost. Failure to receive an acknowledgment of a Message (a GoodCRC Message) whether caused by a bad GoodCRC Message on the receiving end or by a garbled Message within tReceive is detected when the CRCReceiveTimer expires. The sender's Protocol Layer response when a CRCReceiveTimer expires Shall be to retry nRetryCount times. Note: Cable Plugs do not retry Messages and large Extended Messages that are not Chunked are not retried (see Section 6.7.2, "Retry Counter"). Sending of the Preamble corresponding to the retried Message Shall start within tRetry of the CRCReceiveTimer expiring. The CRCReceiveTimer Shall be started when the last bit of the Message EOP has been transmitted by the PHY Layer. The CRCReceiveTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer. The Protocol Layer receiving a Message Shall respond with a GoodCRC Message within tTransmit in order to ensure that the sender's CRCReceiveTimer does not expire. The tTransmit time Shall be measured from when the last bit of the Message EOP has been received by the PHY Layer until the first bit of the Preamble of the GoodCRC Message has been transmitted by the PHY Layer. 6.6.2 SenderResponseTimer The SenderResponseTimer Shall be used by the sender's Policy Engine to ensure that a Message requesting a response (e.g., Get_Source_Cap Message) is responded to within a bounded time of tSenderResponse. Failure to receive the expected response is detected when the SenderResponseTimer expires. For Extended Messages received as Chunks, the SenderResponseTimer will also be started and stopped by the Chunking Rx State Machine. See Section 8.3.3.1.1, "SenderResponseTimer State Diagram" for more details of the SenderResponseTimer operation. The Policy Engine's response when the SenderResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The SenderResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the Message requesting a response, has been received by the PHY Layer. The SenderResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected response Message, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tReceiverResponse in order to ensure that the sender's SenderResponseTimer does not expire. The tReceiverResponse time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the expected request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.3 Capability Timers Sources and Sinks use Capability Timers to determine Attachment of a PD Capable device. By periodically sending or requesting Capabilities, it is possible to determine PD device Attachment when a response is received. Page 250 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.3.1 SourceCapabilityTimer Prior to the First Explicit Contract a Source Shall use the SourceCapabilityTimer to periodically send out a Source_Capabilities Message every tTypeCSendSourceCap while:  The Port is Attached.  The Source is not in an active connection with a PD Sink Port. Whenever there is a SourceCapabilityTimer timeout the Source Shall send a Source_Capabilities Message. It Shall then re-initialize and restart the SourceCapabilityTimer. The SourceCapabilityTimer Shall be stopped when the last bit of the EOP corresponding to the GoodCRC Message has been received by the PHY Layer since a PD connection has been established. At this point, the Source waits for a Request Message or a response timeout. Note: The Source can also stop sending Source_Capabilities Message after nCapsCount Messages have been sent without a GoodCRC Message response (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.2, "Policy Engine Source Port State Diagram" for more details of when Source_Capabilities Messages are transmitted. 6.6.3.2 SinkWaitCapTimer The Sink Shall support the SinkWaitCapTimer. While in a Default Contract or an Implicit Contract when a Sink observes an absence of Source_Capabilities Messages, after VBUS is present, for a duration of tTypeCSinkWaitCap the Sink May issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter") or continue to operate at USB Type-C current. When a Sink, entering EPR Mode, observes an absence of EPR_Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to exit EPR Mode (see Section 6.4.10, "EPR_Mode Message"). When a Sink, exiting EPR Mode, observes an absence of Source_Capabilities Messages, after the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit), for a duration of tTypeCSinkWaitCap the Sink Shall issue Hard Reset Signaling in order to restart the sending of Source_Capabilities Messages by the Source (see Section 6.7.4, "Capabilities Counter"). See Section 8.3.3.3, "Policy Engine Sink Port State Diagram" for more details of when the SinkWaitCapTimer is run. 6.6.3.3 tFirstSourceCap After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap a Source Shall send its first Source_Capabilities Message within tFirstSourceCap of VBUS reaching vSafe5V. After Soft Reset, a Source Shall send its first Source Capabilities Message within tFirstSourceCap after last bit of the GoodCRC Message EOP corresponding to Accept Message. This ensures that the Sink receives a Source Capabilities Message before the Sink's SinkWaitCapTimer expires. A Source entering EPR Mode Shall send its first EPR_Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 3 (Enter Succeeded). A Source exiting EPR Mode Shall send its first Source_Capabilities Message within tFirstSourceCap of the GoodCRC Message acknowledging the EPR_Mode Message with the Action field set to 5 (Exit). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 251 6.6.4 Wait Timers and Times 6.6.4.1 SinkRequestTimer The SinkRequestTimer is used to ensure that the time before the next Sink Request Message, after a Wait Message has been received from the Source in response to a Sink Request Message, is a minimum of tSinkRequest min (see Section 6.3.12, "Wait Message"). The SinkRequestTimer Shall be started when the EOP of a Wait Message has been received and Shall be stopped if any other Message is received or during a Hard Reset. The Sink Shall wait at least tSinkRequest, after receiving the EOP of a Wait Message sent in response to a Sink Request Message, before sending a new Request Message. Whenever there is a SinkRequestTimer timeout the Sink May send a Request Message. It Shall then re-initialize and restart the SinkRequestTimer. 6.6.4.2 tPRSwapWait The time before the next PR_Swap Message, after a Wait Message has been received in response to a PR_Swap Message is a minimum of tPRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tPRSwapWait after receiving the EOP of a Wait Message sent in response to a PR_Swap Message, before sending a new PR_Swap Message. 6.6.4.3 tDRSwapWait The time before the next DR_Swap Message, after a Wait Message has been received in response to a DR_Swap Message is a minimum of tDRSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tDRSwapWait after receiving the EOP of a Wait Message sent in response to a DR_Swap Message, before sending a new DR_Swap Message. 6.6.4.4 tVCONNSwapWait The time before the next VCONN_Swap Message, after a Wait Message has been received in response to a VCONN_Swap Message is a minimum of tVCONNSwapWait min (see Section 6.3.12, "Wait Message"). The Port Shall wait at least tVCONNSwapWait after receiving the EOP of a Wait Message sent in response to a VCONN_Swap Message, before sending a new VCONN_Swap Message. 6.6.4.5 tVCONNSwapDelayDFP The time delay for DFP after losing VCONN Source role due to an incoming VCONN Swap request from UFP and before sending the next VCONN_Swap Message. The DFP Shall wait at least tVCONNSwapDelayDFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.6 tVCONNSwapDelayUFP The time delay for UFP after losing VCONN Source role due to an incoming VCONN Swap request from DFP and before sending the next VCONN_Swap Message. The UFP Shall wait at least tVCONNSwapDelayUFP after sending the EOP of the GoodCRC Message in response to PS_RDY Message received at the end of the previous VCONN Swap AMS. 6.6.4.7 tEnterUSBWait The time before the next Enter_USB Message, after a Wait Message has been received in response to a Enter_USB Message is a minimum of tEnterUSBWait min (see Section 6.3.12, "Wait Message"). The DFP Shall wait at least tEnterUSBWait after receiving the EOP of a Wait Message sent in response to an Enter_USB Message, before sending a new Enter_USB Message. 6.6.5 Power Supply Timers See Section 7.3, "Transitions" for diagrams showing the usage of the timers in this section. Page 252 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.5.1 PSTransitionTimer The PSTransitionTimer is used by the Policy Engine to timeout on a PS_RDY Message. It is started when a request for new Source Capabilities has been accepted and will timeout after tPSTransition if a PS_RDY Message has not been received. This condition leads to a Hard Reset and a return to USB Default Operation. The PSTransitionTimer relates to the time taken for the Source to transition from one voltage, or current level, to another (see Section 7.1, "Source Requirements"). The PSTransitionTimer Shall be started when the last bit of the GoodCRC Message EOP, corresponding to an Accept Message, has been transmitted by the PHY Layer. The PSTransitionTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer. 6.6.5.2 PSSourceOffTimer 6.6.5.2.1 Use during Power Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is currently acting as a Sink to timeout on a PS_RDY Message during a Power Role Swap AMS. This condition leads to USB Type-C Error Recovery. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Source the Sink can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this transmitted Accept Message, is received by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. If a PR_Swap Message request has been sent by the Dual-Role Power Device currently acting as a Sink the Source can respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this received Accept Message, is transmitted by the Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the remote Dual-Role Power Device to stop supplying power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the remote Dual-Role Power Device within tPSSourceOff indicating this has occurred. 6.6.5.2.2 Use during Fast Role Swap The PSSourceOffTimer is used by the Policy Engine in Dual-Role Power Device that is the Initial Sink (currently providing vSafe5V) to timeout on a PS_RDY Message during a Fast Role Swap AMS. This condition leads to USB Type-C Error Recovery. When the FR_Swap Message request has been sent by the Initial Sink, the Initial Source Shall respond with an Accept Message. When the last bit of the GoodCRC Message EOP, corresponding to this Accept Message is received by the Initial Sink's PHY Layer, then the PSSourceOffTimer Shall be started. The PSSourceOffTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmitted by the PHY Layer. The PSSourceOffTimer relates to the time taken for the Initial Source to stop supplying power and for VBUS to revert to vSafe5V (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap"). The timer Shall time out if a PS_RDY Message has not been received from the Initial Source within tPSSourceOff indicating this has occurred. 6.6.5.3 PSSourceOnTimer 6.6.5.3.1 Use during Power Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Power Role Swap. This condition leads to USB Type-C Error Recovery. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 253 The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer.  The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.3.2.1, "Sink Requested Power Role Swap" and Section 7.3.2.2, "Source Requested Power Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.5.3.2 Use during Fast Role Swap The PSSourceOnTimer is used by the Policy Engine in Dual-Role Power Device that has just stopped sourcing power and is waiting to start sinking power to timeout on a PS_RDY Message during a Fast Role Swap. This condition leads to USB Type-C Error Recovery. The PSSourceOnTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the transmitted PS_RDY Message, is re- ceived by the PHY Layer. The PSSourceOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the received PS_RDY Message, is transmit- ted by the PHY Layer. The PSSourceOnTimer relates to the time taken for the remote Dual-Role Power Device to start sourcing power (see also Section 7.2.10, "Fast Role Swap" and Section 7.3.4, "Transitions Caused by Fast Role Swap") and will time out if a PS_RDY Message indicating this has not been received within tPSSourceOn. 6.6.6 NoResponseTimer The NoResponseTimer is used by the Policy Engine in a Source to determine that its Port Partner is not responding after a Hard Reset. When the NoResponseTimer times out, the Policy Engine Shall issue up to nHardResetCount additional Hard Resets before determining that the Port Partner is non-responsive to USB Power Delivery messaging. If the Source fails to receive a GoodCRC Message in response to a Source_Capabilities Message within tNoResponse of:  The last bit of a Hard Reset Signaling being sent by the PHY Layer if the Hard Reset Signaling was initi- ated by the Sink.  The last bit of a Hard Reset Signaling being received by the PHY Layer if the Hard Reset Signaling was initiated by the Source. Then the Source Shall issue additional Hard Resets up to nHardResetCount times (see Section 6.8.3, "Hard Reset"). For a non-responsive device, the Policy Engine in a Source May either decide to continue sending Source_Capabilities Messages or to go to non-USB Power Delivery operation and cease sending Source_Capabilities Messages. 6.6.7 BIST Timers 6.6.7.1 tBISTCarrierMode tBISTCarrierMode is used to define the maximum time that a UUT has to enter BIST Carrier Mode when requested by a Tester. Page 254 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 A UUT Shall enter BIST Carrier Mode within tBISTCarrierMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. In BIST Carrier Mode when transmitting a continuous carrier signal transmission Shall start as soon as the UUT enters BIST Mode. 6.6.7.2 BISTContModeTimer The BISTContModeTimer is used by a UUT to ensure that a Continuous BIST Mode (i.e., BIST Carrier Mode) is exited in a timely fashion. A UUT that has been put into a Continuous BIST Mode Shall return to normal operation (either PE_SRC_Transition_to_default, PE_SNK_Transition_to_default, or PE_CBL_Ready) within tBISTContMode of starting to transmit a continuous carrier signal. 6.6.7.3 tBISTSharedTestMode tBISTSharedTestMode is used to define the maximum time that a UUT has to enter BIST Shared Capacity Test Mode when requested by a Tester. A UUT Shall enter BIST Shared Capacity Test Mode and send a new Source_Capabilities Message from all Ports within the Shared Capacity Group within tBISTSharedTestMode of the last bit of the GoodCRC Message EOP, corresponding to the received the BIST Message used to initiate the test, being transmitted by the PHY Layer. 6.6.8 Power Role Swap Timers 6.6.8.1 SwapSourceStartTimer The SwapSourceStartTimer Shall be used by the New Source, after a Power Role Swap or Fast Role Swap, to ensure that it does not send Source_Capabilities Message before the New Sink is ready to receive the Source_Capabilities Message. The New Source Shall Not send the Source_Capabilities Message earlier than tSwapSourceStart after the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. The Sink Shall be ready to receive a Source_Capabilities Message tSwapSinkReady after having sent the last bit of the EOP of GoodCRC Message sent in response to the PS_RDY Message sent by the New Source indicating that its power supply is ready. 6.6.9 Soft Reset Timers 6.6.9.1 tSoftReset A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure. This Shall cause the Source or Sink to send a Soft_Reset Message, transmission of which Shall be completed within tSoftReset of the CRCReceiveTimer expiring. 6.6.9.2 tProtErrSoftReset If the Protocol Error occurs that causes the Source or Sink to send a Soft_Reset Message, the transmission of the Soft_Reset Message Shall be completed within tProtErrSoftReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.10 Data Reset Timers 6.6.10.1 VCONNDischargeTimer The VCONNDischargeTimer is used by the Policy Engine in the DFP to ensure the UFP actively discharges VCONN in a timely manner to ensure the cable will restore Ra. Once the UFP has discharged VCONN below vRaReconnect (see [USB Type-C 2.4]) it sends a PS_RDY Message (see also Section 7.1.15, "VCONN Power Cycle"). If the DFP does not receive a PS_RDY Message from the UFP within tVCONNSourceDischarge of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message, the VCONNDischargeTimer will time out and the Policy Engine Shall enter the ErrorRecovery State. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 255 6.6.10.2 tDataReset The DFP Shall complete the Data_Reset process (as defined in Section 6.3.14, "Data_Reset Message") within tDataReset of the last bit of the GoodCRC Message EOP, corresponding to the Accept Message, being transmitted by the PHY Layer. 6.6.10.3 DataResetFailTimer The DataResetFailTimer Shall be used by the DFP's Policy Engine to ensure the Data Reset process completes within tDataResetFail of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the DFP's DataResetFailTimer expires, the DFP Shall enter the ErrorRecovery State. 6.6.10.4 DataResetFailUFPTimer The DataResetFailUFPTimer Shall be used by the UFP's Policy Engine to ensure the Data Reset process completes within tDataResetFailUFP of the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message. If the UFP's DataResetFailUFPTimer expires, the UFP Shall enter the ErrorRecovery State. 6.6.11 Hard Reset Timers 6.6.11.1 HardResetCompleteTimer The HardResetCompleteTimer is used by the Protocol Layer in the case where it has asked the PHY Layer to send Hard Reset Signaling and the PHY Layer is unable to send the Signaling within a reasonable time due to a non-Idle channel. If the PHY Layer does not indicate that the Hard Reset Signaling has been sent within tHardResetComplete of the Protocol Layer requesting transmission, then the Protocol Layer Shall inform the Policy Engine that the Hard Reset Signaling has been sent in order to ensure the power supply is reset in a timely fashion. 6.6.11.2 PSHardResetTimer The PSHardResetTimer is used by the Policy Engine in a Source to ensure that the Sink has had sufficient time to process Hard Reset Signaling before turning off its power supply to VBUS. When a Hard Reset occurs the Source, stops driving VCONN, removes Rp from the CC pin and starts to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. See Section 7.1.5, "Response to Hard Resets". 6.6.11.3 tDRSwapHardReset If a DR_Swap Message is received during Modal Operation then a Hard Reset Shall be initiated by the recipient of the unexpected DR_Swap Message; Hard Reset Signaling Shall be generated within tDRSwapHardReset of the EOP of the GoodCRC sent in response to the DR_Swap Message. 6.6.11.4 tProtErrHardReset If a Protocol Error occurs that directly leads to a Hard Reset, the transmission of the Hard Reset Signaling Shall be completed within tProtErrHardReset of the EOP of the GoodCRC sent in response to the Message that caused the Protocol Error. 6.6.12 Structured VDM Timers 6.6.12.1 VDMResponseTimer The VDMResponseTimer Shall be used by the Initiator's Policy Engine to ensure that a Structured VDM Command request needing a response (e.g. Discover Identity Command request) is responded to within a bounded time of tVDMSenderResponse. The VDMResponseTimer Shall be applied to all Structured VDM Commands except the Page 256 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Enter Mode and Exit Mode Commands which have their own timers (VDMModeEntryTimer and VDMModeExitTimer respectively). Failure to receive the expected response is detected when the VDMResponseTimer expires. The Policy Engine's response when the VDMResponseTimer expires Shall be dependent on the Message sent (see Section 8.3, "Policy Engine"). The VDMResponseTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMResponseTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected VDM Command response, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMReceiverResponse in order to ensure that the sender's VDMResponseTimer does not expire. The tVDMReceiverResponse time Shall be measured from the time the last bit of the Message EOP has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.2 VDMModeEntryTimer The VDMModeEntryTimer Shall be used by the Initiator's Policy Engine to ensure that the response to a Structured VDM Enter Mode Command request (ACK or NAK with ACK indicating that the requested Alternate Mode has been entered) arrives within a bounded time of tVDMWaitModeEntry. Failure to receive the expected response is detected when the VDMModeEntryTimer expires. The Policy Engine's response when the VDMModeEntryTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.1, "DFP Structured VDM Mode Entry State Diagram"). The VDMModeEntryTimer Shall be started from the time the last bit of the EOP of the GoodCRC Message, corresponding to the VDM Command request, has been received by the PHY Layer. The VDMModeEntryTimer Shall be stopped when the last bit of the EOP of the GoodCRC Message, corresponding to the expected Structured VDM Command response (ACK, NAK or BUSY), has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMEnterMode in order to ensure that the sender's VDMModeEntryTimer does not expire. The tVDMEnterMode time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to VDM Command Request, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.12.3 VDMModeExitTimer The VDMModeExitTimer Shall be used by the Initiator's Policy Engine to ensure that the ACK response to a Structured VDM Exit Mode Command, indicating that the requested Alternate Mode has been exited, arrives within a bounded time of tVDMWaitModeExit. Failure to receive the expected response is detected when the VDMModeExitTimer expires. The Policy Engine's response when the VDMModeExitTimer expires is to inform the Device Policy Manager (see Section 8.3.3.23.2, "DFP Structured VDM Mode Exit State Diagram"). The VDMModeExitTimer Shall be started from the time the last bit of the GoodCRC Message EOP, corresponding to the VDM Command requesting a response, has been received by the PHY Layer. The VDMModeExitTimer Shall be stopped when the last bit of the GoodCRC Message EOP, corresponding to the expected Structured VDM Command response ACK, has been transmitted by the PHY Layer. The receiver of a Message requiring a response Shall respond within tVDMExitMode in order to ensure that the sender's VDMModeExitTimer does not expire. The tVDMExitMode time Shall be measured from the time the last bit of the Message EOP has been received by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 257 6.6.12.4 tVDMBusy The Initiator Shall wait at least tVDMBusy, after receiving a BUSY Command response, before repeating the Structured VDM request again. 6.6.13 VCONN Timers 6.6.13.1 VCONNOnTimer The VCONNOnTimer is used during a VCONN Swap. The VCONNOnTimer Shall be started when:  The last bit of GoodCRC Message EOP, corresponding to the Accept Message, is transmitted or received by the PHY Layer. The VCONNOnTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, is transmitted by the PHY Layer. Prior to sending the PS_RDY Message, the Port Shall have turned VCONN On. 6.6.13.2 tVCONNSourceOff The tVCONNSourceOff time applies during a VCONN Swap. The initial VCONN Source Shall cease sourcing VCONN within tVCONNSourceOff of the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, being transmitted by the PHY Layer. 6.6.14 tCableMessage Ports compliant with Revision 3.x of the specification Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet even when communicating using [USBPD 2.0] with a Cable Plug. This specification defines Collision Avoidance mechanisms that obviate the need for this time. Cable Plugs Shall only wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet when operating at [USBPD 2.0]. When operating at Revisions higher than [USBPD 2.0] Cable Plugs Shall Not wait tCableMessage before sending an SOP’ Packet or SOP’’ Packet. 6.6.15 DiscoverIdentityTimer The DiscoverIdentityTimer is used prior to or during an Explicit Contract when discovering whether a Cable Plug is PD Capable using SOP’. When performing Cable Discovery during an Explicit Contract the Discover Identity Command request Shall be sent every tDiscoverIdentity. No more than nDiscoverIdentityCount Discover Identity Messages without a GoodCRC Message response Shall be sent. If no GoodCRC Message response is received after nDiscoverIdentityCount Discover Identity Command requests have been sent by a Port, the Port Shall Not send any further SOP’/SOP’’ Messages. 6.6.16 Collision Avoidance Timers 6.6.16.1 SinkTxTimer The SinkTxTimer is used by the Protocol Layer in a Source to allow the Sink to complete its transmission before initiating an AMS. The Source Shall wait a minimum of tSinkTx after changing Rp from SinkTxOK to SinkTxNG before initiating an AMS by sending a Message. A Sink Shall only initiate an AMS when it has determined that Rp is set to SinkTxOK. Page 258 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.16.2 tSrcHoldsBus If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. 6.6.17 Fast Role Swap Timers 6.6.17.1 tFRSwap5V The tFRSwap5V time Shall be measured from:  The later of:  The last bit of the GoodCRC Message EOP, corresponding to the Accept Message or  VBUS being within vSafe5V.  Until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. During a Fast Role Swap, the Initial Source Shall start the PS_RDY Message within tFRSwap5V after both:  The Initial Source has sent the Accept Message, and  VBUS is at or below vSafe5V. 6.6.17.2 tFRSwapComplete During a fast-role swap, the Initial Sink Shall respond with a the PS_RDY Message within tFRSwapComplete after it has received the PS_RDY Message from the Initial Source. The tFRSwapComplete time Shall be measured from the time the last bit of the GoodCRC Message EOP, corresponding to the PS_RDY Message, has been transmitted by the PHY Layer until the first bit of the response PS_RDY Message Preamble has been transmitted by the PHY Layer. 6.6.17.3 tFRSwapInit That last bit of the EOP of the FR_Swap Message Shall be transmitted by the New Source no later than tFRSwapInit after the Fast Role Swap Request has been detected (see Section 5.8.6.3, "Fast Role Swap Detection"). 6.6.18 Chunking Timers 6.6.18.1 ChunkingNotSupportedTimer The ChunkingNotSupportedTimer is used by a Source or Sink which does not support multi-chunk Chunking but has received a Message Chunk. The ChunkingNotSupportedTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to a Message Chunk of a multi-chunk Message, is transmitted by the PHY Layer. The Policy Engine Shall Not send its Not_Supported Message before the ChunkingNotSupportedTimer expires. 6.6.18.2 ChunkSenderRequestTimer The ChunkSenderRequestTimer is used during a Chunked Message transmission. The ChunkSenderRequestTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Response is responded to within a bounded time of tChunkSenderRequest. Failure to receive the expected response is detected when the ChunkSenderRequestTimer expires. The ChunkSenderRequestTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is received by the PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 259 The ChunkSenderRequestTimer Shall be stopped when:  The last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, is trans- mitted by the PHY Layer.  A Message other than a Chunk Request is received from the Protocol Layer Rx. The receiver of a Chunk Response requiring a Chunk Request Shall respond with a Chunk Request within tChunkReceiverRequest in order to ensure that the sender's ChunkSenderRequestTimer does not expire. The tChunkReceiverRequest time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Response Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.18.3 ChunkSenderResponseTimer The ChunkSenderResponseTimer is used during a Chunked Message transmission. The ChunkSenderResponseTimer Shall be used by the sender's Chunking state machine to ensure that a Chunk Request is responded to within a bounded time of tChunkSenderResponse. Failure to receive the expected response is detected when the ChunkSenderResponseTimer expires. The ChunkSenderResponseTimer Shall be started when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Request Message, is received by the PHY Layer. The ChunkSenderResponseTimer Shall be stopped when:  The last bit of the GoodCRC Message EOP, corresponding to the Chunk Response Message, is transmitted by the PHY Layer.  A Message other than a Chunk is received from the Protocol Layer. The receiver of a Chunk Request requiring a Chunk Response Shall respond with a Chunk Response within tChunkReceiverResponse in order to ensure that the sender's ChunkSenderResponseTimer does not expire. The tChunkReceiverResponse time Shall be measured from the time the last bit of the EOP of the GoodCRC Message, corresponding to the Chunk Request Message, has been transmitted by the PHY Layer until the first bit of the response Message Preamble has been transmitted by the PHY Layer. 6.6.19 Programmable Power Supply Timers 6.6.19.1 SinkPPSPeriodicTimer The SinkPPSPeriodicTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSRequest when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is sent periodically as a keep alive mechanism. SinkPPSPeriodicTimer Shall be re-initialized and restarted on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any received Message, that causes the Sink to enter the PE_SNK_Ready state. The Sink Shall stop the SinkPPSPeriodicTimer on transmission, by the PHY Layer, of the last bit of the GoodCRC Message EOP, corresponding to any Message, or the last bit of any Signaling is received, by the PHY Layer, from the Source and by the Sink that causes the Sink to leave the PE_SNK_Ready state. 6.6.19.2 SourcePPSCommTimer The SourcePPSCommTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tPPSTimeout when in SPR PPS Mode. In the absence of any other traffic, a Request Message requesting an SPR PPS APDO is received periodically as a keep alive mechanism. Page 260 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SourcePPSCommTimer Shall be re-initialized and restarted when, after receiving any Message that causes the Source to enter the PE_SRC_Ready state, the last bit of the corresponding GoodCRC Message EOP is transmitted by the PHY Layer. The Source Shall stop the SourcePPSCommTimer when:  After receiving any Message that causes the Source to leave the PE_SRC_Ready state, the last bit of the of the corresponding GoodCRC Message EOP is sent by the PHY Layer, or  The last bit of any Signaling is received by the PHY Layer from the Sink by the Source that causes the Source to leave the PE_SRC_Ready state. When the SourcePPSCommTimer times out the Source Shall issue Hard Reset Signaling. 6.6.20 tEnterUSB The DFP Shall send the Enter_USB Message within tEnterUSB of either:  The last bit of the GoodCRC acknowledging the Data_Reset_Complete Message in response to the Data_Reset Message or  A PD Connection, specifically the last bit of the GoodCRC acknowledging the Source_Capabilities Mes- sage after the initial entry into the PE_SRC_Send_Capabilities state or  The last bit of the GoodCRC acknowledging the Accept Message in response to the DR_Swap Message Failure by the DFP to meet this timeout parameter can result in the ports not transitioning into [USB4] operation. Any AMS initiated by the UFP prior to receiving the Enter_USB Message will delay reception of the Enter_USB Message and [USB4] operation, therefore a USB4® -capable UFP Should Not initiate any AMS until the DFP has been given time to send the Enter_USB Message. 6.6.21 EPR Timers 6.6.21.1 SinkEPREnterTimer Timer The SinkEPREnterTimer is used to ensure the EPR Mode entry process completes within tEnterEPR. The Sink Shall start the timer when it sees the last bit of the GoodCRC Message in response to the EPR_Mode Message with the Action field set to 1 (Enter). The Sink Shall stop the timer when the last bit of the corresponding GoodCRC Message EOP, corresponding to the received EPR_Mode Message with the Action field set to 3 (Enter Succeeded), has been transmitted by the PHY Layer. If the timer expires the Sink Shall send a Soft_Reset Message. 6.6.21.2 SinkEPRKeepAlive Timer The SinkEPRKeepAliveTimer Shall be used by the Sink's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSinkEPRKeepAlive. The Sink Shall initialize and run this timer upon entry into the PE_SNK_Ready State when in EPR Mode and Shall stop it upon exit from the PE_SNK_Ready when in EPR Mode. While operating in EPR Mode, the Sink Shall stop the SinkEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Source, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Sink Shall send an EPR_KeepAlive Message. 6.6.21.3 SourceEPRKeepAlive Timer The SourceEPRKeepAliveTimer Shall be used by the Source's Policy Engine to ensure that communication between the Sink and Source occurs within a bounded time of tSourceEPRKeepAlive. The Source Shall initialize Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 261 and run this timer upon entry into the PE_SRC_Ready State when in EPR Mode and Shall disable it upon exit from the PE_SRC_Ready State when EPR Mode. While operating in EPR Mode, the Source Shall stop the SourceEPRKeepAliveTimer timer whenever:  The last bit of the GoodCRC Message EOP, in response any Message from the Sink, is transmitted by the PHY Layer.  The PHY Layer receives the last bit of the GoodCRC Message EOP in response to any Message sent to the Source. If the timer expires the Source Shall send Hard Reset Signaling. 6.6.21.4 tEPRSourceCableDiscovery After Port Partners are Attached or after a Hard Reset or after a Power Role Swap or after a Fast Role Swap an EPR Source Shall discover the Cable Plug within tEPRSourceCableDiscovery of entering the First Explicit Contract. The EPR Source Shall send the Discover Identity REQ Command, to the Cable Plug, within tEPRSourceCableDiscovery of receiving the GoodCRC Message acknowledging the PS_RDY Message as part of the Explicit Contract Negotiation. Note: If the EPR Source is not the VCONN Source, tEPRSourceCableDiscovery, will also include the time needed for the VCONN Swap. Page 262 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.6.22 Time Values and Timers Table 6.68, "Time Values" summarizes the values for the timers listed in this section. For each Timer Value, a given implementation Shall pick a fixed value within the range specified. Table 6.69, "Timers" lists the timers. Table 6.68 Time Values Parameter Value (min) Value (Nom) Value (max) Units Reference tACTempUpdate 500 ms Section 6.5.2.2.1 tBISTContMode 30 45 60 ms Section 6.6.7.2 tBISTCarrierMode 300 ms Section 6.6.7.1 tBISTSharedTestMode 1 s Section 6.6.7.3 tCableMessage 750 µs Section 6.6.14 tCapabilitiesMismatchResponse 2 s Section 6.4.2.3 tChunkingNotSupported 40 45 50 ms Section 6.6.18.1 tChunkReceiverRequest 15 ms Section 6.6.18.2 tChunkReceiverResponse 15 ms Section 6.6.18.3 tChunkSenderRequest 24 27 30 ms Section 6.6.18.2 tChunkSenderResponse 24 27 30 ms Section 6.6.18.3 tDataReset 200 225 250 ms Section 6.6.10.2 tDataResetFail 300 400 ms Section 6.6.10.3 tDataResetFailUFP 450 550 ms Section 6.6.10.4 tDiscoverIdentity 40 50 ms Section 6.6.14 tDRSwapHardReset 15 ms Section 6.6.11.3 tDRSwapWait 100 ms Section 6.6.4.3 tEnterUSB 500 ms Section 6.6.20 tEnterUSBWait 100 ms Section 6.6.4.7 tEnterEPR 450 500 550 ms Section 6.6.21.1 tEPRSourceCableDiscovery 2 s Section 6.6.21.4 tFirstSourceCap 250 ms Section 6.6.3.3 tFRSwap5V 15 ms Section 6.6.17.1 tFRSwapComplete 15 ms Section 6.6.17.2 tFRSwapInit 15 ms Section 6.6.17.3 tHardReset 5 ms Section 6.3.13 tHardResetComplete 4 4.5 5 ms Section 6.6.9 tSourceEPRKeepAlive 0.750 0.875 1.000 s Section 6.6.21.3 tSinkEPRKeepAlive 0.250 0.375 0.500 s Section 6.6.21.2 tNoResponse 4.5 5.0 5.5 s Section 6.6.6 tPPSRequest 10 s Section 6.6.19.1 tPPSTimeout 12.0 13.5 15.0 s Section 6.6.19.2 tProtErrHardReset 15 ms Section 6.6.11.4 tProtErrSoftReset 15 ms Section 6.6.9.2 tPRSwapWait 100 ms Section 6.6.4.2 tPSHardReset 25 30 35 ms Section 6.6.11.2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 263 tPSSourceOff SPR Mode 750 835 920 ms Section 6.6.5.2 EPR Mode 1120 1260 1400 tPSSourceOn SPR Mode 390 435 480 ms Section 6.6.5.3 tPSTransition SPR Mode 450 500 550 ms Section 6.6.5.1 EPR Mode 830 925 1020 tReceive 0.9 1.0 1.1 ms Section 6.6.1 tReceiverResponse 15 ms Section 6.6.2 tRetry 195 µs Section 6.6.1 tSenderResponse 27 30 33 ms Section 6.6.2 tSinkDelay 5 ms Section 5.7 tSinkRequest 100 ms Section 6.6.4.1 tSinkTx 16 18 20 ms Section 6.6.16 tSoftReset 15 ms Section 6.8.1 tSrcHoldsBus 50 ms Section 8.3.3.2 tSwapSinkReady 15 ms Section 6.6.8.1 tSwapSourceStart 20 ms Section 6.6.8.1 tTransmit 195 µs Section 6.6.1 tTypeCSendSourceCap 100 150 200 ms Section 6.6.3.1 tTypeCSinkWaitCap 310 465 620 ms Section 6.6.3.2 tVCONNSourceDischarge 160 200 240 ms Section 6.6.10.1 tVCONNSourceOff 25 ms Section 6.6.13 tVcONNSourceOn 50 ms Section 6.3.11 tVCONNSourceTimeout 100 150 200 ms Section 6.6.13 tVCONNSwapWait 100 ms Section 6.6.4.4 tVCONNSwapDelayDFP 100 ms Section 6.6.4.5 tVCONNSwapDelayUFP 500 ms Section 6.6.4.6 tVDMBusy 50 ms Section 6.6.12.4 tVDMEnterMode 25 ms Section 6.6.12.2 tVDMExitMode 25 ms Section 6.6.12.3 tVDMReceiverResponse 15 ms Section 6.6.12.1 tVDMSenderResponse 24 27 30 ms Section 6.6.12.1 tVDMWaitModeEntry 40 45 50 ms Section 6.6.12.2 tVDMWaitModeExit 40 45 50 ms Section 6.6.12.3 Table 6.68 Time Values (Continued) Parameter Value (min) Value (Nom) Value (max) Units Reference Page 264 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 6.69 Timers Timer Parameter Used By Reference BISTContModeTimer tBISTContMode Policy Engine Section 6.6.7.2 ChunkingNotSupportedTimer tChunkingNotSupported Policy Engine Section 6.6.18.1 ChunkSenderRequestTimer tChunkSenderRequest Protocol Layer Section 6.6.18.2 ChunkSenderResponseTimer tChunkSenderResponse Protocol Layer Section 6.6.18.3 CRCReceiveTimer tReceive Protocol Layer Section 6.6.1 DataResetFailTimer tDataResetFail Policy Engine Section 6.6.10.3 DataResetFailUFPTimer tDataResetFailUFP Policy Engine Section 6.6.10.4 DiscoverIdentityTimer tDiscoverIdentity Policy Engine Section 6.6.15 HardResetCompleteTimer tHardResetComplete Protocol Layer Section 6.6.9 NoResponseTimer tNoResponse Policy Engine Section 6.6.6 PSHardResetTimer tPSHardReset Policy Engine Section 6.6.11.2 PSSourceOffTimer tPSSourceOff Policy Engine Section 6.6.5.2 PSSourceOnTimer tPSSourceOn Policy Engine Section 6.6.5.3 PSTransitionTimer tPSTransition Policy Engine Section 6.6.5.1 SenderResponseTimer tSenderResponse Policy Engine Section 6.6.2 SinkEPREnterTimer tEnterEPR Policy Engine Section 6.6.21.1 SinkEPRKeepAliveTimer tSinkEPRKeepAlive Policy Engine Section 6.6.21.2 SinkPPSPeriodicTimer tPPSRequest Policy Engine Section 6.6.19.1 SinkRequestTimer tSinkRequest Policy Engine Section 6.6.4 SinkWaitCapTimer tTypeCSinkWaitCap Policy Engine Section 6.6.3.2 SourceCapabilityTimer tTypeCSendSourceCap Policy Engine Section 6.6.3.1 SourceEPRKeepAliveTimer tSourceEPRKeepAlive Policy Engine Section 6.6.21.3 SourcePPSCommTimer tPPSTimeout Policy Engine Section 6.6.19.2 SinkTxTimer tSinkTx Protocol Layer Section 6.6.16 SwapSourceStartTimer tSwapSourceStart Policy Engine Section 6.6.8.1 VCONNDischargeTimer tVCONNSourceDischarge Policy Engine Section 6.6.10.1 VCONNOnTimer tVCONNSourceTimeout Policy Engine Section 6.6.13.1 VDMModeEntryTimer tVDMWaitModeEntry Policy Engine Section 6.6.12.2 VDMModeExitTimer tVDMWaitModeExit Policy Engine Section 6.6.12.3 VDMResponseTimer tVDMSenderResponse Policy Engine Section 6.6.12.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 265 6.7 Counters 6.7.1 MessageID Counter The MessageIDCounter is a rolling counter, ranging from 0 to nMessageIDCount, used to detect duplicate Messages. This value is used for the MessageID field in the Message Header of each transmitted Message. Each Port Shall maintain a copy of the last MessageID value received from its Port Partner. Devices that support multiple ports, such as Hubs, Shall maintain copies of the last MessageID on a per Port basis. A Port which communicates using SOP* Packets Shall maintain copies of the last MessageID for each type of SOP* it uses. The transmitter Shall use the MessageID in a GoodCRC Message to verify that a particular Message was received correctly. The receiver Shall use the MessageID to detect duplicate Messages. 6.7.1.1 Transmitter Usage The Transmitter Shall use the MessageID as follows:  Upon receiving either Hard Reset Signaling, or a Soft_Reset Message, the transmitter Shall set its MessageIDCounter to zero and re-initialize its retry mechanism.  If a GoodCRC Message with a MessageID matching the MessageIDCounter is not received before the CRCReceiveTimer expires, it Shall retry the same Packet up to nRetryCount times using the same MessageID.  If a GoodCRC Message is received with a MessageID matching the current MessageIDCounter before the CRCReceiveTimer expires, the transmitter Shall re-initialize its retry mechanism and increment its MessageIDCounter.  If the Message is aborted by the Policy Engine, the transmitter Shall delete the Message from its transmit buffer, re-initialize its retry mechanism and increment its MessageIDCounter. 6.7.1.2 Receiver Usage The Receiver Shall use the MessageID as follows:  When the first good Packet is received after a reset, the receiver Shall store a copy of the received MessageID value.  For subsequent Messages, if MessageID value in a received Message is the same as the stored value, the receiver Shall return a GoodCRC Message with that MessageID value and drop the Message (this is a retry of an already received Message). Note: This Shall Not apply to the Soft_Reset Message which always has a MessageID value of zero.  If MessageID value in the received Message is different than the stored value, the receiver Shall return a GoodCRC Message with the new MessageID value, store a copy of the new MessageID value and pro- cess the Message. 6.7.2 Retry Counter The RetryCounter is used by a Port whenever there is a Message transmission failure (timeout of CRCReceiveTimer). If the nRetryCount retry fails, then the link Shall be reset using the Soft Reset mechanism. The following rules apply to retries when there is a Message transmission failure (see also Section 6.12.2.2, "Protocol Layer Message Transmission"):  Cable Plugs Shall Not retry Messages.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are not Chunked (Chunked flag set to zero) Shall Not be retried. Page 266 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Extended Messages of Data Size ≤ MaxExtendedMsgLegacyLen (Chunked flag set to zero or one) Shall be retried.  Extended Messages of Data Size > MaxExtendedMsgLegacyLen that are Chunked (Chunked flag set to one) individual Chunks Shall be retried. When Messages are not retried, then the RetryCounter is not used. Higher layer protocols are expected to accommodate Message delivery failure or failure to receive a GoodCRC Message. 6.7.3 Hard Reset Counter The HardResetCounter is used to retry the Hard Reset whenever there is no response from the remote device (see Section 6.6.6, "NoResponseTimer"). Once the Hard Reset has been retried nHardResetCount times then it Shall be assumed that the remote device is non-responsive. 6.7.4 Capabilities Counter The CapsCounter is used to count the number of Source_Capabilities Messages which have been sent by a Source at power up or after a Hard Reset. Implementation of the CapsCounter is Optional but May be used by any Source which wishes to preserve power by not sending Source_Capabilities Messages after a period of time. When the CapsCounter is implemented and the Source detects that a Sink is Attached then after nCapsCount Source_Capabilities Messages have been sent the Source Shall decide that the Sink is non-responsive, stop sending Source_Capabilities Messages and disable PD. A Sink Shall use the SinkWaitCapTimer to trigger the resending of Source_Capabilities Messages by a USB Power Delivery capable Source which has previously stopped sending Source_Capabilities Messages. Any Sink which is Attached and does not detect a Source_Capabilities Message, Shall issue Hard Reset Signaling when the SinkWaitCapTimer times out in order to reset the Source. Resetting the Source Shall also reset the CapsCounter and restart the sending of Source_Capabilities Messages. 6.7.5 Discover Identity Counter When sending Discover Identity Messages to a Cable Plug a Port Shall maintain a count of Messages sent (DiscoverIdentityCounter). No more than nDiscoverIdentityCount Discover Identity Messages Shall be sent by the Port without receiving a GoodCRC Message response. A VCONN Swap Shall reset the DiscoverIdentityCounter. 6.7.6 VDMBusyCounter When sending Responder BUSY responses to a Structured Vendor_Defined Message a UFP or Cable Plug Shall maintain a count of Messages sent (VDMBusyCounter). No more than nBusyCount Responder BUSY responses Shall be sent. The VDMBusyCounter Shall be reset on sending a non-BUSY response. Products wishing to meet [USB Type-C 2.4] requirements for Alternate Mode entry Should use an nBusyCount of 1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 267 6.7.7 Counter Values and Counters Table 6.70, "Counter Parameters" lists the counters used in this section and Table 6.71, "Counters" shows the corresponding parameters. Table 6.70 Counter Parameters Parameter Value Reference nBusyCount 5 Section 6.7.6 nCapsCount 50 Section 6.7.4 nDiscoverIdentityCount 20 Section 6.7.5 nHardResetCount 2 Section 6.7.3 nMessageIDCount 7 Section 6.7.1 nRetryCount 2 Section 6.7.2 Table 6.71 Counters Counter Max Reference CapsCounter nCapsCount Section 6.7.4 DiscoverIdentityCounter nDiscoverIdentityCount Section 6.7.5 HardResetCounter nHardResetCount Section 6.7.3 MessageIDCounter nMessageIDCount Section 6.7.1 RetryCounter nRetryCount Section 6.7.2 VDMBusyCounter nBusyCount Section 6.7.6 Page 268 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.8 Reset Resets are a necessary response to protocol or other error conditions. USB Power Delivery defines four different types of reset:  Soft Reset, which resets protocol.  Data Reset which resets the USB Communications.  Hard Reset which resets both the power supplies and protocol  Cable Reset which resets the cable. 6.8.1 Soft Reset and Protocol Error A Soft_Reset Message is used to cause a Soft Reset of protocol communication when this has broken down in some way. It Shall Not have any impact on power supply operation but is used to correct a Protocol Error occurring during an Atomic Message Sequence (AMS). The Soft Reset May be triggered by either Port Partner in response to the Protocol Error. Protocol Errors are any unexpected Message during an AMS. If the first Message in an AMS has been passed to the Protocol Layer by the Policy Engine but has not yet been sent (i.e., a GoodCRC Message acknowledging the Message has not been received) when the Protocol Error occurs, the Policy Engine Shall Not issue a Soft Reset but Shall return to the PE_SNK_Ready or PE_SRC_Ready state and then process the incoming Message. If the incoming Message is an Unexpected Message received in the PE_SNK_Ready or PE_SRC_Ready state, the Policy Engine Shall issue a Soft Reset. If the Protocol Error occurs during an AMS this Shall lead to a Soft Reset in order to re-synchronize the Policy Engine state machines (see Section 8.3.3.4, "SOP Soft Reset and Protocol Error State Diagrams") except when the voltage is transition when a Protocol Error Shall lead to a Hard Reset (see Section 6.6.11.4, "tProtErrHardReset" and Section 8.3.3.2, "Policy Engine Source Port State Diagram"). Details of AMS's can be found in Section 8.3.2.1.3, "Atomic Message Sequences". An Unrecognized Message or Unsupported Message received in the PE_SNK_Ready or PE_SRC_Ready states, Shall Not cause a Soft_Reset Message to be generated but instead a Not_Supported Message Shall be generated. A Soft_Reset Message Shall be sent regardless of the Rp value either SinkTxOK or SinkTxNG if it is the correct response in that state. Note: This means that a Soft_Reset Message can be sent during an AMS regardless of the Rp value either SinkTxOK or SinkTxNG when responding to a Protocol Error. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 269 Table 6.72, "Response to an incoming Message (except VDM)" and Table 6.73, "Response to an incoming VDM" summarize the responses that Shall be made to an incoming Message including VDMs. A failure to see a GoodCRC Message in response to any Message within tReceive (after nRetryCount retries), when a Port Pair is Connected, is indicative of a communications failure resulting in a Soft Reset (see Section 6.6.9.1, "tSoftReset"). A Soft Reset Shall impact the USB Power Delivery layers in the following ways:  PHY Layer: Reset not required since the PHY Layer resets on each Packet transmission/reception.  Protocol Layer: Reset MessageIDCounter, RetryCounter and state machines. Table 6.72 Response to an incoming Message (except VDM) Recipient’s Power Role Recipient’s state Incoming Message Recognized Unrecognized Supported Unsupported Expected Unexpected Source PE_SRC_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (power not transitioning1) Process Message Soft_Reset Message2 During AMS (power transitioning1) Process Message Hard Reset Signaling Sink PE_SNK_Ready Process Message Soft_Reset Message2 Not_Supported Message3 Not_Supported Message3 (except for VDM) See Section 6.4.4.1 for UVDM. See Section 6.4.4.1 for SVDM During AMS (not power transitioned) Process Message Soft_Reset Message2 During AMS (power transitioned) Process Message Hard Reset Signaling 1) “Power transitioning” means the Policy Engine is in PE_SRC_Transition_Supply State or PE_SNK_Transition_Sink State or PE_FRS_SNK_SRC_Start_AMS State. 2) The Soft_Reset Message Shall be sent using the SOP* of the incoming Message. 3) The Not_Supported Message Shall be sent using the SOP* of the incoming Message. Table 6.73 Response to an incoming VDM Recipient's Role Unstructured VDM Structured VDM Supported Unsupported Unrecognized Supported Unsupported Unrecognized DFP or UFP Defined by vendor Not_Supported Message Not_Supported Message See Section 6.13.5 Not_Supported Message NAK Command Cable Plug Defined by vendor Message Ignored Message Ignored See Section 6.13.5 Message Ignored NAK Command Page 270 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Policy Engine: Reset state dependent behavior by performing an Explicit Contract Negotiation.  Power supply: Shall Not change. Note: When in SPR Mode the Source sends a Source_Capabilities Message and when in EPR Mode the Source sends an EPR_Source_Capabilities Message. A Soft Reset is performed using an AMS (see Table 8.8, "AMS: Soft Reset"). Message numbers Shall be set to zero prior to sending the Soft_Reset/Accept Message since the issue might be with the counters. The sender of a Soft_Reset Message Shall reset its MessageIDCounter and RetryCounter, the receiver of the Message Shall reset its MessageIDCounter and RetryCounter before sending the Accept Message response. Any failure in the Soft Reset process will trigger a Hard Reset when SOP Packets are being used or Cable Reset, sent by the DFP only, for any other SOP* Packets; for example a GoodCRC Message is not received during the Soft Reset process (see Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). 6.8.2 Data Reset A Data_Reset Message is used by a Port to reset its USB data connection and to exit all Alternate Modes both with its Port Partner and in the Cable Plug(s).  The Data Reset process May be initiated by either Port Partner sending a Data_Reset Message. A Data Reset impacts USB Power Delivery in the following ways:  Shall Not change the Port Power Roles (Source/Sink) or Port Data Roles (DFP/UFP).  Shall Not change the existing Explicit Contract.  Shall cause all Active Modes to be exited.  Shall reset the cable by Power cycling VCONN.  The DFP Shall become the VCONN Source.  If the Data Reset process fails, then the Port Shall enter the ErrorRecovery State as defined in [USB Type-C 2.4]. See Section 6.3.14, "Data_Reset Message" for details of Data Reset operation. 6.8.3 Hard Reset Hard Resets are signaled by an ordered set as defined in Section 5.6.4, "Hard Reset". Both the sender and recipient Shall cause their power supplies to return to their default states (see Section 7.3.3.1, "Source Initiated Hard Reset" and Section 7.3.3.2, "Sink Initiated Hard Reset" for details of voltage transitions). In addition, their respective Protocol Layers Shall be reset as for the Soft Reset. This allows the Attached devices to be in a state where they can re-establish USB PD communication. Hard Reset is retried up to nHardResetCount times (see also Section 6.6.6, "NoResponseTimer" and Section 6.7.3, "Hard Reset Counter"). Note: Even though VBUS drops to vSafe0V during a Hard Reset a Sink will not see this as a disconnect since this is expected behavior. A Hard Reset Shall Not cause any change to either the Rp/Rd resistor being asserted. If there has been a Data Role Swap the Hard Reset Shall cause the Port Data Role to be changed back to DFP for a Port with the Rp resistor asserted and UFP for a Port with the Rd resistor asserted. When VCONN is supported (see [USB Type-C 2.4]) the Hard Reset Shall cause the Port with the Rp resistor asserted to supply VCONN and the Port with the Rd resistor asserted to turn off VCONN. In effect the Hard Reset will revert the Ports to their default state based on their CC line resistors. Removing and reapplying VCONN from the Cable Plugs also ensures that they re-establish their configuration as either SOP’ or SOP’’ based on the location of VCONN (see [USB Type-C 2.4]). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 271 If the Hard Reset is insufficient to clear the error condition, then the Port Shall use USB Type-C ErrorRecovery as defined in [USB Type-C 2.4]. A Sink Shall be able to send Hard Reset Signaling regardless of the value of Rp (see Section 5.7, "Collision Avoidance"). 6.8.3.1 Cable Plugs and Hard Reset Cable Plugs Shall Not generate Hard Reset Signaling but Shall monitor for Hard Reset Signaling between the Port Partners and Shall reset when this is detected (see Section 8.3.3.25.2.2, "Cable Plug Hard Reset State Diagram"). The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. 6.8.3.2 Modal Operation and Hard Reset A Hard Reset Shall cause EPR Mode and all Active Modes to be exited by both Port Partners and any Cable Plugs (see Section 6.4.4.3.4, "Enter Mode Command"). 6.8.4 Cable Reset Cable Resets are signaled by an ordered set as defined in Section 5.6.5, "Cable Reset". Both the sender and recipient of Cable Reset Signaling Shall reset their respective Protocol Layers. The Cable Plugs Shall perform the equivalent of a power cycle returning to their initial power up state. This allows the Port Partners to be in a state where they can re-establish USB PD communication. The DFP must be supplying VCONN prior to a Cable Reset. If VCONN has been turned off the DFP Shall turn on VCONN prior to generating Cable Reset Signaling. If there has been a VCONN Swap and the UFP is currently supplying VCONN, the DFP Shall perform a VCONN Swap such that it is supplying VCONN prior to generating Cable Reset Signaling. Only a DFP Shall generate Cable Reset Signaling. A DFP Shall only generate Cable Reset Signaling within an Explicit Contract. A Cable Reset Shall cause all Active Modes in the Cable Plugs to be exited (see Section 6.4.4.3.4, "Enter Mode Command"). Page 272 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.9 Accept, Reject and Wait The recipient of a Request, EPR_Request, PR_Swap, DR_Swap, VCONN_Swap, or Enter_USB Message Shall respond by sending one of the following responses:  An Accept Message in response to a Valid request which can be serviced immediately (see Section 6.3.3, "Accept Message").  A Wait Message in response to a Valid request which cannot be serviced immediately but could be ser- viced at a later time (see Section 6.3.12, "Wait Message").  A Reject Message in response to an Invalid request or a request which is outside of the device's design Capabilities (see Section 6.3.4, "Reject Message"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 273 6.10 Collision Avoidance To avoid Message collisions due to asynchronous Messaging sent from the Sink, the Source sets Rp to SinkTxOK to indicate to the Sink that it is OK to initiate an AMS. When the Source wishes to initiate an AMS, it sets Rp to SinkTxNG. When the Sink detects that Rp is set to SinkTxOK it May initiate an AMS. When the Sink detects that Rp is set to SinkTxNG it Shall Not initiate an AMS and Shall only send Messages that are part of an AMS the Source has initiated. Note: This restriction applies to SOP* AMS's i.e., for both Port to Port and Port to Cable Plug communications. If a transition into the PE_SRC_Ready state will result in an immediate transition out of the PE_SRC_Ready state within tSrcHoldsBus e.g. it is due to a Protocol Error that has not resulted in a Soft Reset, then the notifications of the end of AMS and first Message in an AMS May Not be sent to avoid changing the Rp value unnecessarily. Note: A Sink can still send Hard Reset Signaling at any time. Page 274 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.11 Message Discarding On receiving a received Message on SOP, the Protocol Layer Shall Discard any pending SOP* Messages. A received Message on SOP’/SOP’’ Shall Not cause any pending SOP* Messages to be Discarded. It is assumed that Messages using SOP’/SOP’’ constitute a simple request/response AMS, with the Cable Plug providing the response so there is no reason for a pending SOP* Message to be Discarded. There can only be one AMS between the Port Partners, and these also take priority over Cable Plug communications so a Message received on SOP will always cause a Message pending on SOP* to be Discarded. Table 6.74, "Message Discarding" for details of the Messages that Shall/ Shall Not be Discarded. Table 6.74 Message Discarding Message pending transmission Message received Message to be Discarded SOP SOP Outgoing Message SOP SOP’/SOP’’ Incoming Message SOP’ SOP Outgoing Message SOP’ SOP’ Incoming Message SOP’ SOP’’ Incoming Message SOP’’ SOP Outgoing Message SOP’’ SOP’ Incoming Message SOP’’ SOP’’ Incoming Message Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 275 6.12 State behavior 6.12.1 Introduction to state diagrams used in Chapter 6 The state diagrams defined in Section 6.12, "State behavior" are Normative and Shall define the operation of the Power Delivery Protocol Layer. Note: These state diagrams are not intended to replace a well written and robust design. Figure 6.57, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state and in some states "Actions on exit" a list of actions carried out on exiting the state. Figure 6.57 Outline of States Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&." The inverse of a condition is shown with a "NOT" in front of the condition. In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams. Figure 6.57, "Outline of States" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the referenced state. Figure 6.58 References to states Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the state it is referenced. As soon as the state is exited then the timer is no longer active. Timeouts of the timers are listed as conditions on state transitions. Conditions listed on state transitions will come from one of three sources: <Name of State> Actions on entry: “List of actions to carry out on entering the state” Actions on exit: “List of actions to carry out on exiting the state” <Name of reference state> (<DFP | UFP>) Page 276 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Messages received from the PHY Layer.  Events triggered within the Protocol Layer e.g., timer timeouts  Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.) 6.12.2 State Operation The following section details Protocol Layer State Operation when sending and receiving SOP* Packets. For each SOP’ Communication being sent and received there Shall be separate Protocol Layer Transmission and Protocol Layer Reception and Hard Reset State Machine instances, with their own counter and timer instances. When Chunking is supported there Shall be separate Chunked Tx, Chunked Tx, and Chunked Message Router State Machine instances. Soft Reset Shall only apply to the State Machine instances it is targeted at based on the type of SOP* Packet used to send the Soft_Reset Message. The Hard Reset State Machine (including Cable Reset) Shall apply simultaneously to all Protocol Layer State Machine instances active in the DFP, UFP and Cable Plug (if present). 6.12.2.1 Protocol Layer Chunking 6.12.2.1.1 Architecture of Device Including Chunking Layer The Chunking component resides in the Protocol Layer between the Policy Engine and Protocol Tx/Rx. Figure 6.59, "Chunking architecture Showing Message and Control Flow" illustrates the relationship between components. The Chunking Layer comprises three related state machines:  Chunked Rx.  Chunked Tx.  Chunked Message Router. Note: The consequence of this architecture is that the Policy Engine deals entirely in Unchunked Messages. It will not receive (and might not respond to) a Message until all the related chunks have been collated. If a PD device or Cable Plug has no requirement to handle any Message requiring more than one Chunk of any Extended Message, it May omit the Chunking Layer. In this case it Shall implement the ChunkingNotSupportedTimer to ensure compatible operation with partners which support Chunking (see Section 6.6.18.1, "ChunkingNotSupportedTimer" and Section 8.3.3.6, "Not Supported Message State Diagrams"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 277 Figure 6.59 Chunking architecture Showing Message and Control Flow 6.12.2.1.1.1 Optional Abort Mechanism Long Chunked Messages bring with them the potential problem that they could prevent urgent Messages from being transmitted in a timely manner. An Optional Abort mechanism is provided to remedy this problem. The Abort Flag referred to in the diagrams below May be set and examined by the Policy Engine. The specific means are left to the implementer. 6.12.2.1.1.2 Aborting Sending a Long-Chunked Message A long-Chunked Message being sent May be aborted by setting the Optional Abort Flag. The Message Shall be considered aborted when the Abort Flag is again cleared by the Chunked Tx state machine. 6.12.2.1.1.3 Aborting Receiving a Long-Chunked Message If the Optional Abort mechanism has been implemented, any Message sent while a Chunked Message receive is in progress will result in an error report being received by the Policy Engine, to indicate that the Message request has been Discarded. If the Message was urgent the Policy Engine might set the Abort Flag, which will result in the incoming Chunked Message being aborted. The Abort Flag being cleared by the Chunked Rx state machine indicates that the urgent Message can now be sent. 6.12.2.1.2 Chunked Rx State Diagram Figure 6.60, "Chunked Rx State Diagram" shows the state behavior for the Chunked Rx State Machine. This recognizes whether Chunked received Messages are involved and deals with requesting chunks when they are. It also performs validity checks on all Messages related to Chunking. Policy Engine Protocol Layer Rx Protocol Layer Tx PHY Layer Rp Control or Detection Chunked Rx Chunked Tx Chunking Protocol Layer Hard Reset Chunked Message Router AMS Notification Page 278 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 6.60 Chunked Rx State Diagram 6.12.2.1.2.1 RCH_Wait_For_Message_From_Protocol_Layer State The Chunked Rx State Machine Shall enter the RCH_Wait_For_Message_From_Protocol_Layer state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine clears the Extended Rx Buffer and clears the Optional Abort Flag. In the RCH_Wait_For_Message_From_Protocol_Layer state the Chunked Rx state machine waits until the Chunked Message Router passes up a received Message. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  A non-Extended Message is passed up from the Chunked Message Router.  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are not doing Chunking, and the Message has its Chunked bit set to 0b. The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  An Extended Message is passed up from the Chunked Message Router, and the Policy Engine has determined that we are doing Chunking, and the Message has its Chunked bit set to 1b. 6.12.2.1.2.2 RCH_Pass_Up_Message State On entry to the RCH_Pass_Up_Message state the Chunked Rx state machine Shall pass the received Message to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Message has been passed. Transmission Error from Protocol Layer | Message Received from Protocol Layer Other Message Received from Protocol Layer | ChunkSenderResponseTimer timeout RCH_Pass_Up_Message Actions on entry: Pass Message to Policy Engine RCH_Wait_For_Message_From_Protocol_Layer Actions on entry: Clear Extended Rx Buffer Clear Abort Flag RCH_Report_Error Actions on entry: Report Error to Policy Engine. If a Message was received, pass it to the Policy Engine. RCH_Processing_ Extended_Message Actions on entry: If first chunk: set Chunk_Number_Expected = 0 and Num bytes received = 0 If expected Chunk Number: Append data to Extended_Message_Buffer; Increment Chunk_Number_Expected and adjust Num bytes received. RCH_Requesting_Chunk Actions on entry: Send notification SRT_Stop to SenderResponseTimer State Machine. Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. RCH_Waiting_Chunk Actions on entry: Start ChunkSenderResponseTimer3 Send notification SRT_Start to SenderResponseTimer State Machine.3 Start Message not Complete Message Transmitted received from Protocol Layer Unexpected Chunk Number Reported Chunked != Chunking1 Received Non-Extended Message | (Received Extended Message & (Chunking1 = 0 & Chunked = 0) ) Message is Complete (Num bytes received >= specified Data Size)2 Message Passed Chunk Response Received from Protocol Layer Received Extended Message & (Chunking1 = 1 & Chunked = 1) Any Message Received and not in state RCH_Waiting_Chunk or RCH_Wait_For_Message_From_ Protocol_Layer Abort Flag Set Soft Reset occured | Exit from Hard Reset 1) Chunking is an internal state that is set to 1 if the ‘Unchunked Extended Messages Supported’ bit in either Source Capabilities or Request is 0. It defaults to 1 and is set after the first exchange of Source Capabilities and Request. It is also set to 1 for SOP’ or SOP’’ communication. 2) Additional bytes received over specified Data Size will be because of padding in the last chunk. 3) This state is responsible for starting two timers of similar length. The implementor Should mitigate against more than one of these timers resulting in recovery action. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 279 6.12.2.1.2.3 RCH_Processing_Extended_Message State On entry to the RCH_Processing_Extended_Message state the Chunked Rx state machine Shall:  If this is the first chunk:  Set Chunk_Number_Expected = 0.  Set Num bytes received = 0.  If chunk contains the expected Chunk Number:  Append its data to the Extended_Message_Buffer.  Increment Chunk_Number_Expected.  Adjust Num bytes received. The Chunked Rx State Machine Shall transition to the RCH_Pass_Up_Message state when:  The Message is complete (i.e., Num bytes received >= specified Data Size. Note: The inequality allows for padding bytes in the last chunk, which are not actually part of the Extended Mes- sage). The Chunked Rx State Machine Shall transition to the RCH_Requesting_Chunk state when:  The Message is not yet complete. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  An unexpected Chunk Number is received. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The Optional Abort Flag is set. 6.12.2.1.2.4 RCH_Requesting_Chunk State On entry to the RCH_Requesting_Chunk state the Chunked Rx state machine Shall:  Send notification SRT_Stop to SenderResponseTimer state machine (see Section 8.3.3.1.1, "SenderResponseTimer State Diagram").  Send Chunk Request to Protocol Layer with Chunk Number = Chunk_Number_Expected. The Chunked Rx State Machine Shall transition to the RCH_Waiting_Chunk state when:  Message Transmitted is received from the Protocol Layer. The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  Transmission Error is received from the Protocol Layer, or  A Message is received from the Protocol Layer. 6.12.2.1.2.5 RCH_Waiting_Chunk State On entry to the RCH_Waiting_Chunk state the Chunked Rx state machine Shall:  Start the ChunkSenderResponseTimer.  Send notification SRT_Start to SenderResponseTimer state machine (see SSection 8.3.3.1.1, "SenderResponseTimer State Diagram"). The Chunked Rx State Machine Shall transition to the RCH_Processing_Extended_Message state when:  A Chunk is received from the Protocol Layer. Page 280 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Rx State Machine Shall transition to the RCH_Report_Error state when:  A Message, other than a Chunk, is received from the Protocol Layer, or  The ChunkSenderResponseTimer expires. 6.12.2.1.2.6 RCH_Report_Error State The Chunked Rx State Machine Shall enter the RCH_Report_Error state:  When any Message is received and the Chunked Rx State Machine is not in one of the states RCH_Waiting_Chunk or RCH_Wait_For_Message_From_Protocol_Layer. On entry to the RCH_Report_Error state the Chunked Rx state machine Shall:  Report the error to the Policy Engine.  If the state was entered because a Message was received, this Message Shall be passed to the Policy Engine. The Chunked Rx State Machine Shall transition to the RCH_Wait_For_Message_From_Protocol_Layer state when:  The error has been reported.  Any Message received was passed to the Policy Engine. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 281 6.12.2.1.3 Chunked Tx State Diagram Figure 6.61, "Chunked Tx State Diagram" shows the state behavior for the Chunked Tx State Machine. This recognizes whether Chunked transmitted Messages are involved and deals with sending chunks and waiting for chunk requests when they are. It also performs validity checks on all related Messages related to Chunking. Figure 6.61 Chunked Tx State Diagram 6.12.2.1.3.1 TCH_Wait_For_Message_Request_From_Policy_Engine State The Chunked Tx State Machine Shall enter the TCH_Wait_For_Message_Request_From_Policy_Engine state:  At startup.  As a result of a Soft Reset occurring.  On exit from a Hard Reset. On entry to the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx state machine clears the Optional Abort Flag. In the TCH_Wait_For_Message_Request_From_Policy_Engine state the Chunked Tx State Machine waits until the Policy Engine sends it a Message Request. The Chunked Tx State Machine Shall transition to the TCH_Pass_Down_Message state when:  A non-Extended Message Request is received from the Policy Engine, or  A Message Request is received from the Policy Engine and the link is not Chunking. TCH_Sending_ Chunked_Message Actions on entry: TCH_ Wait_ For_Message_Request_From_Policy_Engine Actions on entry: Clear Abort Flag TCH_Pass_Down_Message Actions on entry: Pass Message to Protocol Layer TCH_Construct_ Chunked_Message Actions on entry: Construct Message Chunk and pass to Protocol Layer TCH_Wait_For_ Transmision_Complete Actions on entry: TCH_Prepare_To_Send_ Chunked_Message Actions on entry: 'Chunk Number To Send' = 0 TCH_Wait_Chunk_Request Actions on entry: Increment Chunk Number to Send Start ChunkSenderRequestTimer TCH_Report_Error Actions on entry: Report Error to Policy Engine Soft Reset occured | Exit from Hard Reset Start Non-Extended Message Request | Not Chunking Message Passed Message Transmitted received from Protocol Layer TCH_Message_Sent Actions on entry: Inform Policy Engine of Message Sent Any Message Received and not in state TCH_Wait_Chunk_Request Chunking & Extended Message Request Chunk Number Set Chunk Passed Message Transmitted from Protocol Layer & Not Last Chunk TCH_Message_Received Actions on entry: Clear Extended Message Buffers Pass Message to Chunked Rx Message passed to Chunked Rx Message Transmitted received from Protocol Layer & Last Chunk (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Supported Abort Flag Set Informed Chunk Request Rcvd & Chunk Number = Chunk Number to Send Reported Other Message Received (Rx Chunking State != RCH_Wait_For_ Message_From_ Protocol_Layer) & Abort Not Supported Tx Error from Protocol Layer ChunkSenderRequestTimer timeout & Chunk Number = 0 (Chunk Request Rcvd & Chunk Number != Chunk Number to Send) | (ChunkSenderRequestTimer timeout & Chunk Number > 0) Transmission Error Page 282 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Prepare_To_Send_Chunked_Message state when:  An Extended Message Request is received from the Policy Engine, and the link is Chunking. The Chunked Tx State Machine Shall Discard the Message Request and remain in the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer, and the Optional Abort Flag has not been implemented. The Chunked Tx State Machine Shall Discard the Message Request and enter the TCH_Report_Error state when:  The Chunked Rx state is any other than RCH_Wait_For_Message_From_Protocol_Layer and the Optional Abort Flag has been implemented. 6.12.2.1.3.2 TCH_Pass_Down_Message State On entry to the TCH_Pass_Down_Message state the Chunked Tx State Machine Shall pass the Message to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Transmision_Complete state when:  The Message has been passed to the Protocol Layer. 6.12.2.1.3.3 TCH_Wait_For_Transmision_Complete State The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted has been received from the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.4 TCH_Message_Sent State On entry to the TCH_Message_Sent state the Chunked Tx State Machine Shall:  Inform the Policy Engine that the Message has been sent. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The Policy Engine has been informed. 6.12.2.1.3.5 TCH_Prepare_To_Send_Chunked_Message State On entry to the TCH_Prepare_To_Send_Chunked_Message state the Chunked Tx State Machine Shall:  Set 'Chunk Number To Send' to zero. The Chunked Tx State Machine Shall transition to the TCH_Construct_Chunked_Message state when:  ‘Chunk Number To Send' has been set to zero. 6.12.2.1.3.6 TCH_Construct_Chunked_Message State On entry to the TCH_Construct_Chunked_Message state the Chunked Tx State Machine Shall:  Construct a Message Chunk and pass it to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Sending_Chunked_Message state when:  The Message Chunk has been passed to the Protocol Layer. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 283  The Optional Abort Flag is set. 6.12.2.1.3.7 TCH_Sending_Chunked_Message State The Chunked Tx State Machine Shall transition to the TCH_Wait_Chunk_Request state when:  Message Transmitted is received from Protocol Layer and this was not the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  Message Transmitted is received from Protocol Layer and this was the last chunk. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  Transmission Error has been received from the Protocol Layer. 6.12.2.1.3.8 TCH_Wait_Chunk_Request State On entry to the TCH_Wait_Chunk_Request state the Chunked Tx State Machine Shall:  Increment Chunk Number to Send.  Start ChunkSenderRequestTimer. The Chunked Tx State Machine Shall transition to the TCH_Report_Error state when:  A Chunk Request has been received and the Chunk Number does not equal Chunk Number to Send or  ChunkSenderRequestTimer has expired and Chunk Number is greater than zero. The Chunked Tx State Machine Shall transition to the TCH_Message_Sent state when:  ChunkSenderRequestTimer has expired and Chunk Number equals zero. Note: This is the mechanism which allows the remote Port Partner or Cable Plug to omit the Chunking Layer. The Policy Engine will receive a Message Sent signal if the remote Port Partner or Cable Plug is present (GoodCRC Message received) but does not send a Chunk Request. After this the remote Port Partner will send a Not_Supported Message, or the Cable Plug will Ignore the Chunked Message. The Chunked Tx State Machine Shall transition to the TCH_Message_Received state when:  Any other Message than Chunk Request is received. 6.12.2.1.3.9 TCH_Message_Received State The Chunked Tx State Machine Shall enter the TCH_Message_Received state:  When any Message is received, and the Chunked Tx State Machine is not in the TCH_Wait_Chunk_Request state. On entry to the TCH_Message_Received state the Chunked Tx State Machine Shall:  Clear the Extended Message Buffers.  Pass the received Message to Chunked Rx Engine. The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The received Message has been passed to the Chunked Rx Engine. 6.12.2.1.3.10 TCH_Report_Error State On entry to the TCH_Report_Error state the Chunked Tx State Machine Shall:  Report the error to the Policy Engine. Page 284 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Chunked Tx State Machine Shall transition to the TCH_Wait_For_Message_Request_From_Policy_Engine state when:  The error has been reported. 6.12.2.1.4 Chunked Message Router State Diagram Figure 6.62, "Chunked Message Router State Diagram" shows the state behavior for the Chunked Message Router. This determines to which state machine an incoming Message is routed to (Chunked Rx, Chunked Tx or direct to Policy Engine). Figure 6.62 Chunked Message Router State Diagram 6.12.2.1.4.1 RTR_Wait_for_Message_From_Protocol_Layer State In the RTR_Wait_for_Message_From_Protocol_Layer state the Chunked Message Router waits until the Protocol Layer sends it a received Message. The Chunked Message Router Shall transition to the RTR_Rx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is not doing Tx Chunks. The Chunked Message Router Shall transition to the RTR_Tx_Chunks state when:  A Message is received from the Protocol Layer, and the combined Chunking is doing Tx Chunks. 6.12.2.1.4.2 RTR_Rx_Chunks State On entry to the RTR_Rx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Rx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. RTR_Wait_for_Message_From_Protocol_Layer Actions on entry: RTR_Rx_Chunks Actions on entry: Send message to Rx Chunk Machine RTR_Tx_Chunks Actions on entry: Send message to Tx Chunk Machine Message Received from Protocol Layer & Not Doing Tx Chunks1 Message Received from Protocol Layer & Doing Tx Chunks1 Sent Soft Reset occured | Exit from Hard Reset Start Sent 1) Doing Tx Chunks means that Chunked Tx State Machine is not in the TCH_Wait_For_Message_Request_From_Policy_Engine state. 2) Messages are taken to include notification about transmission success or otherwise of Messages. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 285 6.12.2.1.4.3 RTR_Tx_Chunks State On entry to the RTR_Tx_Chunks state the Chunked Message Router Shall:  Send the Message to the Chunked Tx State Machine.  Transition to the RTR_Wait_for_Message_From_Protocol_Layer state. Page 286 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2 Protocol Layer Message Transmission 6.12.2.2.1 Common Protocol Layer Message Transmission State Diagram Figure 6.63, "Common Protocol Layer Message Transmission State Diagram" shows the state behavior, common between the Source and the Sink, for the Protocol Layer when transmitting a Message. Figure 6.63 Common Protocol Layer Message Transmission State Diagram 6.12.2.2.1.1 PRL_Tx_PHY_Layer_Reset State The Protocol Layer Shall enter the PRL_Tx_PHY_Layer_Reset state:  At startup.  As a result of a Soft Reset request being received by the PHY Layer.  On exit from a Hard Reset. On entry to the PRL_Tx_PHY_Layer_Reset state the Protocol Layer Shall reset the PHY Layer (clear any outstanding Messages and enable communications). The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  When the PHY Layer reset is complete. 6.12.2.2.1.2 PRL_Tx_Wait_for_Message_Request State In the PRL_Tx_Wait_for_Message_Request state the Protocol Layer waits until the Policy Engine directs it to send a Message.  On entry to the PRL_Tx_Wait_for_Message_Request state the Protocol Layer Shall reset the RetryCounter. Message request received from Policy Engine (except Soft Reset) Message sent to PHY Layer CRCReceiveTimer Timeout | Message discarded bus Idle2 GoodCRC response received from PHY Layer MessageID mismatch (RetryCounter ” nRetryCount) & not Cable Plug & small Extended Message3 (RetryCounter > nRetryCount) | Cable Plug | large Extended Message3 Policy Engine informed of Transmission Error MessageID match Policy Engine informed message sent PRL_Tx_Check_RetryCounter Actions on entry: If DFP or UFP increment and check RetryCounter PRL_Tx_Transmission_Error Actions on entry: Increment MessageIDCounter Inform Policy Engine of Transmission Error PRL_Tx_Construct_Message Actions on entry: Construct message Pass message to PHY Layer PRL_Tx_Wait_for_PHY_response Actions on entry: Initialize and run CRCReceiveTimer1 PRL_Tx_Match_MessageID Actions on entry: Match MessageIDCounter and response MessageID Soft Reset Message request received from Policy Engine Layer Reset Complete PRL_Tx_Message_Sent Actions on entry: Increment MessageIDCounter Inform Policy Engine message sent PRL_Tx_Layer_Reset_for_Transmit Actions on entry: Reset MessageIDCounter. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. PRL_Tx_Wait_for_Message_Request Actions on entry: Reset RetryCounter PRL_Tx_Discard_Message Actions on entry: If any message is currently awaiting transmission Discard4 and increment MessageID Counter Discarding complete Protocol Layer message reception in PRL_Rx_Store_MessageID state | Fast Role Swap signal transmitted | Fast Role Swap signal detected Start Soft Reset Message from PHY Layer | Exit from Hard Reset PRL_Tx_PHY_Layer_Reset Actions on entry: Reset PHY Layer PHY Layer reset complete 1) The CRCReceiveTimer is only started after the PHY has sent the message. If the message is not sent due to a busy channel, then the CRCReceiveTimer will not be started (see Section 6.6.1 “CRCReceiveTimer”). 2) This indication is sent by the PHY Layer when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). The CRCReceiveTimer is not running in this case since no message has been sent. 3) A “small” Extended Message is either an Extended Message with Data Size ζMaxExtendedMsgLegacyLen bytes or an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has been Chunked. A “large” Extended Message is an Extended Message with Data Size > MaxExtendedMsgLegacyLen bytes that has not been Chunked. 4) See Section 6.11 “Message Discarding” for details of when Messages are Discarded . Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 287 The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message request is received from the Policy Engine which is not a Soft_Reset Message. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Message request is received from the Policy Engine which is a Soft_Reset Message. 6.12.2.2.1.3 PRL_Tx_Layer_Reset_for_Transmit State On entry to the PRL_Tx_Layer_Reset_for_Transmit state the Protocol Layer Shall reset the MessageIDCounter. The Protocol Layer Shall transition Protocol Layer Message reception to the PRL_Rx_Wait_for_PHY_Message state (see Section 6.12.2.3.1, "PRL_Rx_Wait_for_PHY_Message state") in order to reset the stored MessageID. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The layer reset actions in this state have been completed. 6.12.2.2.1.4 PRL_Tx_Construct_Message State On entry to the PRL_Tx_Construct_Message state the Protocol Layer Shall construct the Message requested by the Policy Engine, or resend a previously constructed Message, and then pass this Message to the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_PHY_Response state when:  The Message has been sent to the PHY Layer. 6.12.2.2.1.5 PRL_Tx_Wait_for_PHY_Response State On entry to the PRL_Tx_Wait_for_PHY_Response state, once the Message has been sent, the Protocol Layer Shall initialize and run the CRCReceiveTimer (see Section 6.6.1, "CRCReceiveTimer"). The Protocol Layer Shall transition to the PRL_Tx_Match_MessageID state when:  A GoodCRC Message response is received from the PHY Layer. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The CRCReceiveTimer times out.  Or the PHY Layer indicates that a Message has been Discarded due to the channel being busy but the channel is now Idle (see Section 5.7, "Collision Avoidance"). 6.12.2.2.1.6 PRL_Tx_Match_MessageID State On entry to the PRL_Tx_Match_MessageID state the Protocol Layer Shall compare the MessageIDCounter and the MessageID of the received GoodCRC Message. The Protocol Layer Shall transition to the PRL_Tx_Message_Sent state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message match. The Protocol Layer Shall transition to the PRL_Tx_Check_RetryCounter state when:  The MessageIDCounter and the MessageID of the received GoodCRC Message do not match. 6.12.2.2.1.7 PRL_Tx_Message_Sent State On entry to the PRL_Tx_Message_Sent state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine that the Message has been sent. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed that the Message has been sent. Page 288 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.1.8 PRL_Tx_Check_RetryCounter State On entry to the PRL_Tx_Check_RetryCounter state the Protocol Layer in a DFP or UFP Shall increment the value of the RetryCounter and then check it in order to determine whether it is necessary to retry sending the Message. Note: Cable Plugs do not retry Messages and so do not use the RetryCounter. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state in order to retry Message sending when:  RetryCounter ≤ nRetryCount and  This is not a Cable Plug and  This is an Extended Message with Data Size ≤ MaxExtendedMsgLegacyLen or  This is an Extended Message that has been Chunked. The Protocol Layer Shall transition to the PRL_Tx_Transmission_Error state when:  RetryCounter > nRetryCount or  This is a Cable Plug, which does not retry.  This is an Extended Message with Data Size > MaxExtendedMsgLegacyLen that has not been Chunked. 6.12.2.2.1.9 PRL_Tx_Transmission_Error State On entry to the PRL_Tx_Transmission_Error state the Protocol Layer Shall increment the MessageIDCounter and inform the Policy Engine of the transmission error. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  The Policy Engine has been informed of the transmission error. 6.12.2.2.1.10 PRL_Tx_Discard_Message State Protocol Layer Message transmission Shall enter the PRL_Tx_Discard_Message state whenever:  Protocol Layer Message reception receives an incoming Message or  The Fast Role Swap Request is being transmitted (see Section 5.8.5.6, "Fast Role Swap Transmission")  The Fast Role Swap Request is detected (see Section 5.8.6.3, "Fast Role Swap Detection"). On entry to the PRL_Tx_Discard_Message state, if there is a Message queued awaiting transmission, the Protocol Layer Shall Discard the Message according to the rules in Section 6.11, "Message Discarding" and increment the MessageIDCounter. The Protocol Layer Shall transition to the PRL_Tx_PHY_Layer_Reset state when:  Discarding is complete i.e., the Message queue is empty. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 289 6.12.2.2.2 Source Protocol Layer Message Transmission State Diagram Figure 6.64, "Source Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Source when transmitting a Message. Figure 6.64 Source Protocol Layer Message Transmission State Diagram PRL_Tx_Wait_for_Message_Request PRL_Tx_Src_Sink_Tx Actions on entry: Set Rp = SinkTxOk End of AMS notification received from Policy Engine Start of AMS notification received from Policy Engine PRL_Tx_Src_Pending Actions on entry: Start SinkTxTimer PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending & SinkTxTimer timeout Message pending (except Soft Reset) & SinkTxTimer timeout Rp set PRL_Tx_Src_Source_Tx Actions on entry: Set Rp = SinkTxNG Message request from Policy Engine Page 290 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.2.1 PRL_Tx_Src_Sink_Tx State In the PRL_Tx_Src_Sink_Tx state the Source sets Rp to SinkTxOK allowing the Sink to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Sink_Tx state when:  A notification is received from the Policy Engine that the end of an AMS has been reached. On entry to the PRL_Tx_Src_Sink_Tx state the Protocol Layer Shall request the PHY Layer to Rp to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Wait_for_Message_Request state when:  Rp has been set. 6.12.2.2.2.2 PRL_Tx_Src_Source_Tx State In the PRL_Tx_Src_Source_Tx state the Source sets Rp to SinkTxNG allowing the Source to start an Atomic Message Sequence (AMS). The Protocol Layer in a Source Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Src_Source_Tx state when:  A notification is received from the Policy Engine that an AMS will be starting. On entry to the PRL_Tx_Src_Source_Tx state the Protocol Layer Shall set Rp to SinkTxNG. The Protocol Layer Shall transition to the PRL_Tx_Src_Pending state when:  A Message request is received from the Policy Engine. 6.12.2.2.2.3 PRL_Tx_Src_Pending State In the PRL_Tx_Src_Pending state the Protocol Layer has a Message buffered ready for transmission. On entry to the PRL_Tx_Src_Pending state the SinkTxTimer Shall be initialized and run. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  The pending Message request from the Policy Engine is not a Soft_Reset Message and  The SinkTxTimer times out. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  The pending Message request from the Policy Engine is a Soft_Reset Message and  The SinkTxTimer times out. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 291 6.12.2.2.3 Sink Protocol Layer Message Transmission State Diagram Figure 6.65, "Sink Protocol Layer Message Transmission State Diagram" shows the state behavior for the Protocol Layer in a Sink when transmitting a Message. Figure 6.65 Sink Protocol Layer Message Transmission State Diagram 6.12.2.2.3.1 PRL_Tx_Snk_Start_of_AMS State In the PRL_Tx_Snk_Start_of_AMS state the Protocol Layer waits for the first Message in a Sink initiated AMS. The Protocol Layer in a Sink Shall transition from the PRL_Tx_Wait_for_Message_Request state to the PRL_Tx_Snk_Start_of_AMS state when:  A notification is received from the Policy Engine that the next Message the Sink will send is the start of an AMS. The Protocol Layer Shall transition to the PRL_Tx_Snk_Pending state when:  A Message request is received from the Policy Engine. PRL_Tx_Wait_for_Message_Request First Message in AMS notification received from Policy Engine PRL_Tx_Snk_Pending Actions on entry: PRL_Tx_Layer_Reset_for_Transmit PRL_Tx_Construct_Message Soft Reset Message pending Message pending (except Soft Reset) & Rp = SinkTxOk PRL_Tx_Snk_Start_of_AMS Actions on entry: Message Request from Policy Engine Page 292 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.2.3.2 PRL_Tx_Snk_Pending State In the PRL_Tx_Snk_Pending state the Protocol Layer has the first Message in a Sink initiated AMS ready to send and is waiting for Rp to transition to SinkTxOK before sending the Message. The Protocol Layer Shall transition to the PRL_Tx_Construct_Message state when:  A Message is Pending that is not a Soft_Reset Message and  Rp is set to SinkTxOK. The Protocol Layer Shall transition to the PRL_Tx_Layer_Reset_for_Transmit state when:  A Soft_Reset Message is pending. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 293 6.12.2.3 Protocol Layer Message Reception Figure 6.66, "Protocol layer Message reception" shows the state behavior for the Protocol Layer when receiving a Message. Figure 6.66 Protocol layer Message reception 6.12.2.3.1 PRL_Rx_Wait_for_PHY_Message state The Protocol Layer Shall enter the PRL_Rx_Wait_for_PHY_Message state:  At startup.  As a result of a Soft Reset request from the Policy Engine.  On exit from a Hard Reset. In the PRL_Rx_Wait_for_PHY_Message state the Protocol Layer waits until the PHY Layer passes up a received Message. The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC state when:  A Message is passed up from the PHY Layer. The Protocol Layer Shall transition to the PRL_Rx_Layer_Reset_for_Receive state when:  A Soft_Reset Message is received from the PHY Layer. Message received from PHY (except Soft Reset) Message passed to Policy Engine (GoodCRC sent | Message discarded bus Idle1) MessageID <> stored MessageID | no stored value MessageID = stored MessageID Start PRL_Rx_Send_GoodCRC Actions on entry: Send GoodCRC message to PHY PRL_Rx_Store_MessageID Actions on entry: Protocol Layer message transmission transitions to PRL_Tx_Discard_Message state2. Store new MessageID Pass message to Policy Engine3 PRL_Rx_Wait_for_PHY_message Actions on entry: PRL_Rx_Check_MessageID Actions on entry: If there is a stored value compare MessageID with stored value. Soft Reset Message received from PHY Soft Reset complete PRL_Rx_Layer_Reset_for_Receive Actions on entry: Reset MessageIDCounter and clear stored MessageID value Protocol Layer message transmission transitions to PRL_Tx_PHY_Layer_Reset state. Soft Reset request from Policy Engine | Exit from Hard Reset Message discarded bus Idle1 1) This indication is sent by the PHY when a message has been Discarded due to CC being busy, and after CC becomes idle again (see Section 5.7 “Collision Avoidance”). Two alternate allowable transitions are shown. 2) In the case of a Ping message being received, in order to maintain robust communications in the presence of collisions, the outgoing message Should Not be Discarded. 3) See Section 6.11 “Message Discarding” for details of when Messages are discarded. Page 294 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.2.3.2 PRL_Rx_Layer_Reset_for_Receive state On entry to the PRL_Rx_Layer_Reset_for_Receive state the Protocol Layer Shall reset the MessageIDCounter and clear the stored MessageID. The Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Wait_for_Message_Request state (see Section 6.12.2.2.1.2, "PRL_Tx_Wait_for_Message_Request State"). The Protocol Layer Shall transition to the PRL_Rx_Send_GoodCRC State when:  The Soft Reset actions in this state have been completed. 6.12.2.3.3 PRL_Rx_Send_GoodCRC state On entry to the PRL_Rx_Send_GoodCRC state the Protocol Layer Shall construct a GoodCRC Message and request the PHY Layer to transmit it. The Protocol Layer Shall transition to the PRL_Rx_Check_MessageID state when:  The GoodCRC Message has been passed to the PHY Layer. When the PHY Layer indicates that a Message has been Discarded due to CC being busy but CC is now Idle (see Section 5.7, "Collision Avoidance"), the Protocol Layer Shall either:  Transition to the PRL_Rx_Check_MessageID state or  Transition to the PRL_Rx_Wait_for_PHY_Message state. 6.12.2.3.4 PRL_Rx_Check_MessageID state On entry to the PRL_Rx_Check_MessageID state the Protocol Layer Shall compare the MessageID of the received Message with its stored value if a value has previously been stored. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The MessageID of the received Message equals the stored MessageID value since this is a Message retry which Shall be Discarded. The Protocol Layer Shall transition to the PRL_Rx_Store_MessageID state when:  The MessageID of the received Message does not equal the stored MessageID value since this is a new Message or  This is the first received Message and no MessageID value is currently stored. 6.12.2.3.5 PRL_Rx_Store_MessageID state On entry to the PRL_Rx_Store_MessageID state the Protocol Layer Shall transition Protocol Layer Message transmission to the PRL_Tx_Discard_Message state, replace the stored value of MessageID with the value of MessageID in the received Message and pass the Message up to the Policy Engine. The Protocol Layer Shall transition to the PRL_Rx_Wait_for_PHY_Message state when:  The Message has been passed up to the Policy Engine. 6.12.2.4 Hard Reset operation Figure 6.57, "Outline of States" shows the state behavior for the Protocol Layer when receiving a Hard Reset or Cable Reset request from the Policy Engine or Hard Reset Signaling or Cable Reset Signaling from the PHY Layer (see also Section 6.8.3, "Hard Reset" and Section 6.8.4, "Cable Reset"). Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 295 Figure 6.67 Hard/Cable Reset 6.12.2.4.1 PRL_HR_Reset_Layer state The PRL_HR_Reset_Layer State defines the mode of operation of both the Protocol Layer transmission and reception state machines during a Hard Reset or Cable Reset. During Hard Reset no USB Power Delivery Protocol Messages are sent or received; only Hard Reset Signaling is present after which the communication channel is assumed to have been disabled by the PHY Layer until completion of the Hard Reset. During Cable Reset no USB Power Delivery Protocol Messages are sent to or received by the Cable Plug but other USB Power Delivery communication May continue. The Protocol Layer Shall enter the PRL_HR_Reset_Layer state from any other state when:  A Hard Reset Request is received from the Policy Engine or  Hard Reset Signaling is received from the PHY Layer or Hard Reset request received from Policy Engine2 | Cable Reset request received from Policy Engine4 | Hard Reset signalling received By PHY Layer | Cable Reset signalling received By PHY Layer3 PHY Hard Reset request sent | PHY Cable Reset request sent Hard Reset complete from Policy Engine | Cable Reset complete from Policy Engine Physical Layer informed PRL_HR_Request_Hard_Reset Actions on entry: Request PHY to perform a Hard Reset or Cable Reset PRL_HR_Reset_Layer Actions on entry: Reset MessageIDCounter. Protocol Layer message transmission transitions to PRL_Tx_Wait_For_Message_Request state. Protocol Layer message reception transitions to PRL_Rx_Wait_for_PHY_Message state. Protocol Layer reset complete & (Hard Reset was Initiated by Policy Engine | Cable Reset was Initiated by Policy Engine) Policy Engine informed Protocol Layer reset complete & (Hard Reset was initiated by Port Partner | Cable Reset received by Cable Plug) PRL_HR_Indicate_Hard_Reset Actions on entry: Inform the Policy Engine of the Hard Reset or Cable Reset Exit from Hard Reset Policy Engine informed PRL_HR_PHY_Hard_Reset_Requested Actions on entry: Inform Policy Engine Hard Reset or Cable Reset request has been sent PRL_HR_Wait_For_PE_Hard_Reset_Complete Actions on entry: Wait for Hard Reset or Cable Reset complete indication from Policy Engine. PRL_HR_PE_Hard_Reset_Complete Actions on entry: Inform Physical Layer Hard Reset or Cable Reset is complete PRL_HR_Wait_For_PHY_Hard_Reset_Complete Actions on entry: Start HardResetCompleteTimer Wait for Hard Reset or Cable Reset complete indication from PHY Hard Reset complete from PHY | Cable Reset complete from PHY | HardResetCompleteTimer timeout1 1) If the HardResetCompleteTimer timeout occurs this means that the PHY is still waiting to send the Hard Reset due to a non-idle channel. This condition will be cleared once the PE Hard Reset is completed. 2) Cable Plugs do not generate Hard Reset signaling but are required to monitor for Hard Reset signaling between the Port Partners and respond by resetting. 3) Cable Reset signaling is only recognized by a Cable Plug. 4) Cable Reset signaling cannot be generated by Cable Plugs. Page 296 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Cable Reset Request is received from the Policy Engine or  Cable Reset Signaling is received from the PHY Layer. On entry to the PRL_HR_Reset_Layer state the Protocol Layer Shall reset the MessageIDCounter. It Shall also reset the states of the Protocol Layer transmission and reception state machines to their starting points. The Protocol Layer transmission state machine Shall transition to the PRL_Tx_Wait_for_Message_Request state. The Protocol Layer reception state machine Shall transition to the PRL_Rx_Wait_for_PHY_Message state. The Protocol Layer Shall transition to the PRL_HR_Request_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has originated from the Policy Engine or  The Cable Reset request has originated from the Policy Engine. The Protocol Layer Shall transition to the PRL_HR_Indicate_Hard_Reset state when:  The Protocol Layer's reset is complete and  The Hard Reset request has been passed up from the PHY Layer or  A Cable Reset request has been passed up from the PHY Layer (Cable Plug only). 6.12.2.4.2 PRL_HR_Indicate_Hard_Reset state On entry to the PRL_HR_Indicate_Hard_Reset state the Protocol Layer Shall indicate to the Policy Engine that either Hard Reset Signaling or Cable Reset Signaling has been received. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when:  The indication to the Policy Engine has been sent. 6.12.2.4.3 PRL_HR_Request_Hard_Reset state On entry to the PRL_HR_Request_Hard_Reset state the Protocol Layer Shall request the PHY Layer to send either Hard Reset Signaling or Cable Reset Signaling. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state when:  The PHY Layer Hard Reset Signaling request has been sent or  The PHY Layer Cable Reset Signaling request has been sent. 6.12.2.4.4 PRL_HR_Wait_for_PHY_Hard_Reset_Complete state In the PRL_HR_Wait_for_PHY_Hard_Reset_Complete state the Protocol Layer Shall start the HardResetCompleteTimer and wait for the PHY Layer to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PHY_Hard_Reset_Requested state when:  A Hard Reset complete indication is received from the PHY Layer or  A Cable Reset complete indication is received from the PHY Layer or  The HardResetCompleteTimer times out. 6.12.2.4.5 PRL_HR_PHY_Hard_Reset_Requested state On entry to the PRL_HR_PHY_Hard_Reset_Requested state the Protocol Layer Shall inform the Policy Engine that the PHY Layer has been requested to perform a Hard Reset or Cable Reset. The Protocol Layer Shall transition to the PRL_HR_Wait_for_PE_Hard_Reset_Complete state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 297  The Indication to the Policy Engine has been sent. 6.12.2.4.6 PRL_HR_Wait_for_PE_Hard_Reset_Complete state In the PRL_HR_Wait_for_PE_Hard_Reset_Complete state the Protocol Layer Shall wait for the Policy Engine to indicate that the Hard Reset or Cable Reset has been completed. The Protocol Layer Shall transition to the PRL_HR_PE_Hard_Reset_Complete state when:  A Hard Reset complete indication is received from the Policy Engine or  A Cable Reset complete indication is received from the Policy Engine. 6.12.2.4.7 PRL_HR_PE_Hard_Reset_Complete On entry to the PRL_HR_PE_Hard_Reset_Complete state the Protocol Layer Shall inform the PHY Layer that the Hard Reset or Cable Reset is complete. The Protocol Layer Shall exit from the Hard Reset and return to normal operation when:  The PHY Layer has been informed that the Hard Reset is complete so that it will re-enable the communications channel. If Hard Reset Signaling is still pending due to a non-Idle channel this Shall be cleared and not sent or  The PHY Layer has been informed that the Cable Reset is complete. Page 298 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 6.12.3 List of Protocol Layer States Table 6.75, "Protocol Layer States" lists the states used by the various state machines. Table 6.75 Protocol Layer States State Name Section Protocol Layer Message Transmission Common Protocol Layer Message Transmission PRL_Tx_PHY_Layer_Reset Section 6.12.2.2.1.1 PRL_Tx_Wait_for_Message_Request Section 6.12.2.2.1.2 PRL_Tx_Layer_Reset_for_Transmit Section 6.12.2.2.1.3 PRL_Tx_Construct_Message Section 6.12.2.2.1.4 PRL_Tx_Wait_for_PHY_Response Section 6.12.2.2.1.5 PRL_Tx_Match_MessageID Section 6.12.2.2.1.6 PRL_Tx_Message_Sent Section 6.12.2.2.1.7 PRL_Tx_Check_RetryCounter Section 6.12.2.2.1.8 PRL_Tx_Transmission_Error Section 6.12.2.2.1.9 PRL_Tx_Discard_Message Section 6.12.2.2.1.10 Source Protocol Layer Message Transmission PRL_Tx_Src_Sink_Tx Section 6.12.2.2.2.1 PRL_Tx_Src_Source_Tx Section 6.12.2.2.2.2 PRL_Tx_Src_Pending Section 6.12.2.2.2.3 Sink Protocol Layer Message Transmission PRL_Tx_Snk_Start_of_AMS Section 6.12.2.2.3.1 PRL_Tx_Snk_Pending Section 6.12.2.2.3.2 Protocol Layer Message Reception PRL_Rx_Wait_for_PHY_Message Section 6.12.2.3.1 PRL_Rx_Layer_Reset_for_Receive Section 6.12.2.3.2 PRL_Rx_Send_GoodCRC Section 6.12.2.3.3 PRL_Rx_Check_MessageID Section 6.12.2.3.4 PRL_Rx_Store_MessageID Section 6.12.2.3.5 Hard Reset Operation PRL_HR_Reset_Layer Section 6.12.2.4.1 PRL_HR_Indicate_Hard_Reset Section 6.12.2.4.2 PRL_HR_Request_Hard_Reset Section 6.12.2.4.3 PRL_HR_Wait_for_PHY_Hard_Reset_Complete Section 6.12.2.4.4 PRL_HR_PHY_Hard_Reset_Requested Section 6.12.2.4.5 PRL_HR_Wait_for_PE_Hard_Reset_Complete Section 6.12.2.4.6 PRL_HR_PE_Hard_Reset_Complete Section 6.12.2.4.7 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 299 Chunking Chunked Rx RCH_Wait_For_Message_From_Protocol_Layer Section 6.12.2.2.1.1 RCH_Pass_Up_Message Section 6.12.2.2.1.1 RCH_Processing_Extended_Message Section 6.12.2.2.1.1 RCH_Requesting_Chunk Section 6.12.2.2.1.1 RCH_Waiting_Chunk Section 6.12.2.2.1.1 RCH_Report_Error Section 6.12.2.2.1.1 Chunked Tx TCH_Wait_For_Message_Request_From_Policy_Engine Section 6.12.2.1.3.1 TCH_Pass_Down_Message Section 6.12.2.1.3.2 TCH_Wait_For_Transmision_Complete Section 6.12.2.1.3.3 TCH_Message_Sent Section 6.12.2.1.3.4 TCH_Prepare_To_Send_Chunked_Message Section 6.12.2.1.3.5 TCH_Construct_Chunked_Message Section 6.12.2.1.3.6 TCH_Sending_Chunked_Message Section 6.12.2.1.3.7 TCH_Wait_Chunk_Request Section 6.12.2.1.3.8 TCH_Message_Received Section 6.12.2.1.3.9 TCH_Report_Error Section 6.12.2.1.3.10 Chunked Message Router RTR_Wait_for_Message_From_Protocol_Layer Section 6.12.2.1.4.1 RTR_Rx_Chunks Section 6.12.2.1.4.2 RTR_Tx_Chunks Section 6.12.2.1.4.3 Table 6.75 Protocol Layer States (Continued) State Name Section Page 300 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13 Message Applicability The following tables outline the Messages supported by a given Port, depending on its capability. When a Message is supported the feature and the AMS implied by the Message Shall also be supported. The abbreviations in Table 6.76, "Message Applicability Abbreviations" are used in this section to denote the level of support required. For the case of Conditional Normative a note has been added to indicate the condition. "CN/" notation is used to indicate the level of support when the condition is not present. "R/" and "O/" notation is used to indicate the response when the Recommended or Optional Message is not supported. Note: Where NS/R/NK is indicated for Received Messages this Shall apply to the PE_CBL_Ready, PE_SNK_Ready or PE_SRC_Ready states only since unexpected Messages received during an AMS are Pro- tocol Errors (see Section 6.8.1, "Soft Reset and Protocol Error"). This section covers Control Message and Data Message support for Sources, Sink and Cable Plugs. It also covers VDM Command support for DFPs, UFPs and Cable Plugs. Table 6.76 Message Applicability Abbreviations Abbreviation Meaning Description N Normative Shall be supported by this Port/Cable Plug. CN Conditional Normative Shall supported by a given Port/Cable Plug based on features. R Recommended Should be supported by this Port/Cable Plug. O Optional May be supported by this Port/Cable Plug. NS Not Supported Shall result in a Not_Supported Message response by this Port/Cable Plug when received. I Ignore Shall be Ignored by this Port/Cable Plug when received. NK NAK This Port/Cable Plug Shall return Responder NAK to this Command when received. NA Not allowed Shall Not be transmitted by this Port/Cable Plug. DR Don’t Recognize There Shall be no response at all (i.e., not even a GoodCRC Message) from this Port/Cable Plug when received. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 301 6.13.1 Applicability of Control Messages Table 6.77, "Applicability of Control Messages" details Control Messages that Shall/Should/Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.77 Applicability of Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 Transmitted Message Accept N N N N Data_Reset CN10/R CN10/R NA NA DR_Swap O O N NA NA FR_Swap NA NA R NA NA Get_Country_Codes CN7/NA CN7/NA NA NA Get_PPS_Status NA CN6 NA NA Get_Sink_Cap R NA N NA NA Get_Sink_Cap_Extended R NA R NA NA Get_Source_Cap NA R N NA NA Get_Source_Cap_Extended NA R R NA NA Get_Source_Info NA R R NA NA Get_Revision R R NA NA Get_Status R R NA NA GoodCRC N N N N GotoMin (Deprecated) NA NA NA NA Not_Supported N N NA NA Ping (Deprecated) NA NA NA NA PR_Swap NA NA N NA NA PS_RDY N CN1/NA N NA NA Reject N O O O CN10/NA NA Soft_Reset N N NA NA VCONN_Swap R R NA NA Wait O NA O O NA NA 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Page 302 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Received Message Accept N N N N I I Data_Reset CN10/R CN10/R I I DR_Swap O/NS O/NS N I I FR_Swap NS NS CN4/NS I I Get_Country_Codes CN7/NS CN7/NS I I Get_PPS_Status CN6/NS NS I I Get_Sink_Cap NS N N I I Get_Sink_Cap_Extended NS N N I I Get_Source_Cap N NS N I I Get_Source_Cap_Extended CN2/NS NS CN2/NS I I Get_Source_Info CN11 NS N I I Get_Revision N N O/I O/I Get_Status CN3/NS CN3/NS CN3/NS CN8/I I GoodCRC N N N N GotoMin (Deprecated) NS NS I I Not_Supported N N CN8/I I Ping (Deprecated) NS NS/I I I PR_Swap NS NS N I I PS_RDY CN1/NS N N I I Reject CN5/NS N N N I I Soft_Reset N N N N VCONN_Swap CN1/ NS CN1/ NS I I Wait CN5/NS N N N I I Table 6.77 Applicability of Control Messages (Continued) Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD9 1) Shall be supported by any Port that can supply VCONN. 2) Shall be supported products that support the Source_Capabilities_Extended Message. 3) Shall be supported by Sources that support the Alert Message. 4) Shall be supported when the Fast Role Swap Request is supported. 5) Shall be supported when VCONN Swap is supported. 6) Shall be supported when SPR PPS Mode is supported. 7) Shall be supported when required by a country authority. 8) Shall be supported by Active Cables. 9) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 10) Shall be supported by products that support [USB4]. 11) Shall be supported by all Sources except single Port SPR Chargers with Invariant PDOs. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 303 6.13.2 Applicability of Data Messages Table 6.78, "Applicability of Data Messages" details Data Messages (except for VDM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.78 Applicability of Data Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 Transmitted Message Source_Capabilities N NA N NA NA NA Request NA N NA NA NA Get_Country_Info CN5/O CN5/O NA NA NA BIST N1 N1 NA NA NA Sink_Capabilities NA N N NA NA NA Battery_Status CN2 CN2 NA NA NA Alert CN11/R CN11/R NA NA NA Enter_USB CN7/O CN7/O NA NA NA EPR_Request NA CN9 NA NA NA EPR_Mode CN9 CN9 NA NA NA Source_Info CN10 NA N NA NA NA Revision N N CN12/O/I NA O Received Message Source_Capabilities NS N N I I I Request N NS I I I Get_Country_Info CN5/NS CN5/NS I I I BIST N1 N1 N1 N1 N1 Sink_Capabilities CN4 NS CN4 I I I Battery_Status CN3/NS CN3/NS I I I Alert R/NS R/NS I I I Enter_USB CN7/O CN7/O CN8/I CN8/I I 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Page 304 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 EPR_Request CN9 NA I I I EPR_Mode CN9 CN9 I I I Source_Info NA N N I I I Revision N N I I I Table 6.78 Applicability of Data Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD6 1) For details of which BIST Modes and BIST Messages Shall be supported see Section 5.9 and Section 6.4.3. 2) Shall be supported by products that contain batteries. 3) Shallbe supported by products that support the Get_Battery_Status Message. 4) Shall be supported by products that support the Get_Sink_Cap Message. 5) Shall be supported when required by a country authority. 6) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 7) Shall be supported by products that support [USB4]. 8) Shall be supported by Active Cables that support [USB4]. 9) Shall be supported by products that support Source operation in EPR Mode. 10) Shall be supported by all Source Ports except singlePort SPR Chargers with Invariant PDOs. 11) Shall be supported when SPR PPS Mode is supported. 12) Shall be supported by Active Cables. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 305 6.13.3 Applicability of Extended Messages Table 6.79, "Applicability of Extended Messages" details Extended Messages (except for VDEM Commands) that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual- Role Power Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.79 Applicability of Extended Messages Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 Transmitted Message Battery_Capabilities CN1/NA CN1/NA NA NA NA Country_Codes CN10/NA CN10/NA NA NA NA Country_Info CN10/NA CN10/NA NA NA NA EPR_Source_Capabilities CN14/NA NA CN14/NA NA NA NA EPR_Sink_Capabilities NA CN14/NA CN14/NA NA NA NA Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NA CN7/NA NA NA NA Firmware_Update_Response CN7/NA CN7/NA CN7/NA O NA Get_Battery_Cap R R NA NA NA Get_Battery_Status R R NA NA NA Get_Manufacturer_Info R R NA NA NA Manufacturer_Info R R R NA NA PPS_Status CN8/NA NA NA NA NA Security_Request CN6/NA CN6/NA NA NA NA Security_Response CN6/NA CN6/NA CN6/NA NA NA Sink_Capabilities_Extended NA N N NA NA NA Source_Capabilities_Extended R NA R NA NA NA 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 306 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Status CN15/R CN15/R CN15/R CN12/NA CN12/NA NA Vendor_Defined_Extended O O O O O Received Message Battery_Capabilities CN4/NS CN4/NS I I I Country_Codes CN10/NS CN10/NS I I I Country_Info CN10/NS CN10/NS I I I EPR_Source_Capabilities NS CN14/NS CN14/NS I I I EPR_Sink_Capabilities CN14/NS NS CN14/NS I I I Extended_Control See Section 6.13.4 for details Firmware_Update_Request CN7/NS CN7/NS CN7/I O I Firmware_Update_Response CN7/NS CN7/NS I I I Get_Battery_Cap CN1/NS CN1/NS I I I Get_Battery_Status CN1/NS CN1/NS I I I Get_Manufacturer_Info R/NS R/NS R/I I I Manufacturer_Info CN5/NS CN5/NS I I I PPS_Status NS CN9/NS I I I Security_Request CN6/NS CN6/NS CN6/I I I Security_Response CN6/NS CN6/NS I I I Sink_Capabilities_Extended CN11/NS NS CN11/NS I I I Source_Capabilities_Extended NS CN2/NS CN2/NS I I I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 307 Status CN33/NS CN3/NS I I I Vendor_Defined_Extended O/NS O/NS O/I O/I O/I Table 6.79 Applicability of Extended Messages (Continued) Message Type Source Sink Dual-Role Power Cable Plug SOP’ Cable Plug SOP’’ VPD13 1) Shall be supported by products that contain batteries. 2) Shall be supported by products that can transmit the Get_Source_Cap_Extended Message. 3) Shall be supported by products that can transmit the Get_Status Message. 4) Shall be supported by products that can transmit the Get_Battery_Cap Message. 5) Shall be supported by products that can transmit the Get_Manufacturer_Info Message. 6) Shall be supported by products that support USB security communication as defined in [USBTypeCAuthentication 1.0]. 7) Shall be supported by products that support USB firmware update communication as defined in [USBPDFirmwareUpdate 1.0]. 8) Shall be supported when PPS is supported. 9) Shall be supported by products that can transmit the Get_PPS_Status Message. 10) Shall be supported when required by a country authority. 11) Shall be supported by products that can transmit the Get_Sink_Cap_Extended Message. 12) Shall be supported by Active Cables. 13) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. 14) Shall be supported by products that support operation in EPR Mode. 15) Shall be supported by Sources that support the Alert Message. Page 308 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.4 Applicability of Extended Control Messages Table 6.80, "Applicability of Extended Control Messages" details Extended Control Messages that Shall/Should/ Shall Not be transmitted and received by a Source, Sink, Cable Plug or VPD. Requirements for Dual-Role Power Ports and Dual-Role Data Ports Shall override any requirements for Source-only or Sink-Only Ports. Table 6.80 Applicability of Extended Control Messages Message Type Source Sink Dual-Role Power Dual-Role Data Cable Plug VPD2 Transmitted Message EPR_Get_Source_Cap NA CN1 CN1 NA NA EPR_Get_Sink_Cap CN1 NA CN1 NA NA EPR_KeepAlive NA CN1 NA NA EPR_KeepAlive_Ack CN1 NA NA NA Received Message EPR_Get_Source_Cap CN1 NS CN1 I I EPR_Get_Sink_Cap NS CN1 CN1 I I EPR_KeepAlive CN1 NS I I EPR_KeepAlive_Ack NS CN1 I I 1) Shall be supported by products that support EPR Mode. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 Page 309 6.13.5 Applicability of Structured VDM Commands Table 6.81, "Applicability of Structured VDM Commands" details Structured VDM Commands that Shall/Should/ Shall Not be transmitted and received by a DFP, UFP, Cable Plug or VPD. If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. Table 6.81 Applicability of Structured VDM Commands Command Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD4 Transmitted Command Request Discover Identity CN1,6/R R2 NA NA NA Discover SVIDs CN1/O O NA NA NA Discover Modes CN1/O O NA NA NA Enter Mode CN1/NA NA NA NA NA Exit Mode CN1/NA NA NA NA NA Attention O O NA NA NA Received Command Request/Transmitted Command Response Discover Identity CN5,6/R/ NK3 CN1,6/R/ NK3 N I N Discover SVIDs O/NK3 CN1/NK3 CN1/NK I NK Discover Modes O/NK3 CN1/NK3 CN1/NK I NK Enter Mode NK3 CN1/NK3 CN1/NK O NK Exit Mode NK3 CN1/NK3 CN1/NK O NK Attention O/I3 O/I3 I I I 1) Shall be supported when Modal Operation is supported. 2) May be transmitted by a UFP/Source during discovery (see Section 6.4.4.3.1, "Discover Identity" and Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram"). 3) If Structured VDMs are not supported, the DFP or UFP receiving a VDM Command Shall send a Not_Supported Message in response. 4) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT- VPD Shall only take place when not Connected to a Charger. 5) Shall be supported by products with more than one DFP. 6) Shall be supported by products that support [USB4]. Page 310 Universal Serial Bus Power Delivery SpecificationRevision 3.2, Version 1.1, 2024-10 6.13.6 Applicability of Reset Signaling Table 6.82, "Applicability of Reset Signaling" details the Reset that Shall/Should/ Shall Not be transmitted and received by a DFP/UFP or Cable Plug. 6.13.7 Applicability of Fast Role Swap Request Table 6.83, "Applicability of Fast Role Swap Request" details the Fast Role Swap Request that Shall/Should/ Shall Not be transmitted and received by a Source or Sink. Table 6.82 Applicability of Reset Signaling Reset Type DFP UFP Cable Plug SOP’ Cable Plug SOP’’ VPD2 Transmitted Message/Signaling Soft_Reset N N NA NA NA Hard Reset N N NA NA NA Cable Reset CN1 NA NA NA NA Received Message/Signaling Soft_Reset N N N N N Hard Reset N N N N N Cable Reset DR DR N N N 1) Shall be supported when transmission of SOP’ Packets are supported, and the Port can supply VCONN. 2) VPD includes CT-VPDs when not Connected to a Charger. PD communication with a CT-VPD Shall only take place when not Connected to a Charger. Table 6.83 Applicability of Fast Role Swap Request Command Type Source Sink Dual-Role Power Transmitted Message/Signaling Fast Role Swap NA NA R Received Message/Signaling Fast Role Swap NA NA R Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 311 6.14 Value Parameters Table 6.84, "Value Parameters" contains value parameters used in this section. Table 6.84 Value Parameters Parameter Description Value Unit Reference MaxExtendedMsgLen Maximum length of an Extended Message as expressed in the Data Size field. 260 Byte Section 6.2.1.2 MaxExtendedMsgChunkLen Maximum length of an Extended Message Chunk. 26 Byte Section 6.2.1.2 MaxExtendedMsgLegacyLen Maximum length of an Extended Message that can be sent without Chunking. 26 Byte Section 6.2.1.2
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Page 312 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7 Power Supply 7.1 Source Requirements 7.1.1 Behavioral Aspects A PDUSB Source exhibits the following behaviors:  Shall supply [USB Type-C 2.4] USB Type-C® current to VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS voltage transitions as bound by undershoot, overshoot and transition time requirements. 7.1.2 Source Bulk Capacitance The Source bulk capacitance Shall Not be placed between the transceiver isolation impedance and the USB receptacle. The Source bulk capacitance consists of C1 and C2 as shown in Figure 7.1, "Placement of Source Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect might also be part of the circuit implemented by the Source to limit its VBUS Output Voltage Limit (OVL) as described in Section 7.1.7.5, "Output Voltage Limit". Though a Source Shall limit its output voltage, a Sink Shall implement Sink OVP as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. If the power supply is shared across multiple ports, the bulk capacitance is defined as cSrcBulkShared. If the power supply is dedicated to a single Port, the minimum bulk capacitance is defined as cSrcBulk. The Source bulk capacitance is allowed to change for a newly Negotiated power level. The capacitance change Shall occur before the Source is ready to operate at the new power level. During a Power Role Swap, the Initial Source Shall transition to Swap Standby before operating as the New Sink. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.1 Placement of Source Bulk Capacitance 7.1.3 Types of Sources Consistent with the Power Data Objects discussed in Section 6.4.1, "Capabilities Message", the power supply types that are available as Sources in a USB Power Delivery System are:  The Fixed Supply PDO exposes well-regulated fixed voltage power supplies. Sources Shall support at least one Fixed Supply capable of supplying vSafe5V. The output voltage of a Fixed Supply Shall remain C2 Ohmic Interconnect GND SHIELD VBUS ... Data Lines GND SHIELD VBUS ... Data Lines SOURCE CABLE C1 Power Supply Source Bulk Capacitance OVL Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 313 within the range defined by the relative tolerance vSrcNew and the absolute band vSrcValid as listed in Table 7.23, "Source Electrical Parameters" and described in Section 7.1.8, "Output Voltage Tolerance and Range".  The Variable Supply (non-Battery) PDO exposes less well-regulated Sources. The output voltage of a Variable Supply (non-Battery) Shall remain within the absolute maximum output voltage and the absolute minimum output voltage exposed in the Variable Supply PDO.  The Battery Supply PDO exposes Batteries than can be connected directly as a Source to VBUS. The output voltage of a Battery Supply Shall remain within the absolute maximum output voltage and the absolute minimum output exposed in the Battery Supply PDO.  The Programmable Power Supply (PPS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the Programmable Power Supply Shall remain within a range defined by the relative tolerance vPpsNew and the absolute band vPpsValid.  The Adjustable Voltage Supply (AVS) Augmented Power Data Object (APDO) exposes a Source with an output voltage that can be adjusted programmatically over a defined range. The output voltage of the AVS Shall remain within a range defined by the relative tolerance vAvsNew and the absolute band vAvsValid. 7.1.4 Source Transitions 7.1.4.1 Fixed Supply 7.1.4.1.1 Fixed Supply Positive Voltage Transitions The Source Shall transition VBUS from the starting voltage to the higher new voltage in a controlled manner. The Negotiated new voltage (e.g., 5V, 9V, 15V, …) defines the nominal value for vSrcNew. During the positive transition the Source Should be able to supply the Sink Standby current and the transient current to charge the total bulk capacitance on VBUS. The slew rate of the positive transition Shall Not exceed vSrcSlewPos. The transitioning Source output voltage Shall settle within vSrcNew by tSrcSettle. The Source Shall be able to supply the Negotiated power level at the new voltage by tSrcReady. The positive voltage transition Shall remain above vSrcValid min of the previous Explicit Contract and below vSrcValid max of the new Explicit Contract (Figure 7.2, "Transition Envelope for Positive Voltage Transitions"). The voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.2, "Transition Envelope for Positive Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.2 Transition Envelope for Positive Voltage Transitions At the start of the positive voltage transition the VBUS voltage level Shall Not droop vSrcValid min below either vSrcNew (i.e., if the starting VBUS voltage level is not vSafe5V) or vSafe5V as applicable. Starting voltage vSrcNew(typ) t0 vSrcSlewPos tSrcSettle vSrcValid(max) Upper bound of valid Source range vSrcNew(max) vSrcNew(min) tSrcReady Lower bound of valid Source range § § vSrcValid(min) beyond min/max limits of starting voltage Page 314 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewPos limit. 7.1.4.1.2 Fixed Supply Negative Voltage Transitions Negative voltage transitions are defined as shown in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" and are specified in a similar manner to positive voltage transitions. Figure 7.3, "Transition Envelope for Negative Voltage Transitions" does not apply to vSafe0V transitions. The slew rate of the negative transition Shall Not exceed vSrcSlewNeg. The negative voltage transition Shall remain below vSrcValid max of the previous Explicit Contract and above vSrcValid min of the new Explicit Contract, as shown in FFigure 7.3, "Transition Envelope for Negative Voltage Transitions". The transitioning Source output voltage Shall settle to vSrcNew within tSrcSettle. The starting time, t0, in Figure 7.3, "Transition Envelope for Negative Voltage Transitions" starts tSrcTransition after the last bit of the EOP of the GoodCRC Message has been received by the Source. Figure 7.3 Transition Envelope for Negative Voltage Transitions If the newly Negotiated voltage is vSafe5V, then the vSrcValid limits Shall determine the transition window and the transitioning Source Shall settle within the vSafe5V limits by tSrcSettle. Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vSrcSlewNeg limit. 7.1.4.2 SPR Programmable Power Supply (PPS) 7.1.4.2.1 SPR Programmable Power Supply Voltage Transitions The Programmable Power Supply (PPS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the Programmable RDO defines the nominal value of the PPS output voltage after completing a voltage change and Shall settle within the limits defined by vPpsNew by tPpsSrcTransSmall for steps smaller than or equal to vPpsSmallStep, or else, within the limits defined by vPpsNew by tPpsSrcTransLarge, but only in case the Programmable Power Supply is not in CL mode. Any overshoot beyond vPpsNew Shall Not exceed vPpsValid at any time. Any undershoot beyond vPpsNew Shall Not exceed vPpsValid for currents not resulting in CL mode. The PPS output voltage May change in a step-wise or linear manner and the slew rate of either type of change Shall Not exceed vPpsSlewPos for voltage increases or vPpsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the PPS output voltage is defined as vPpsStep. A PPS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level. All PPS voltage increases Shall Starting voltage Lower bound of valid Source range Upper bound of valid Source range t0 tSrcSettle tSrcReady vSrcNew(typ) vSrcValid(min) vSrcNew(max) vSrcNew(min) § vSrcSlewNeg § vSrcValid(max) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 315 result in a voltage that is greater than or equal to the previous PPS output voltage. Likewise, all PPS voltage decreases Shall result in a voltage that is less than or equal to the previous PPS output voltage. Since a Sink can draw current up to the Negotiated APDO current level in case of a voltage step, the voltage might not increase to the requested level due to the power supply operating in CL mode. Likewise, since a Sink can have a Battery connected to VBUS, the voltage might not decrease to the requested level due to the Battery voltage being higher than the output voltage set point the Source is transitioning to. Were the Source to rely on checking the voltage on VBUS, in either case, to determine when its power supply is ready a PS_RDY Message would never be sent. When the PPS voltage steps up or down, a PS_RDY Message Shall be sent within:  tPpsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vPpsSmallStep.  tPpsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vPpsSmallStep provided that either the voltage on VBUS has reached vPpsNew or the power supply is in CL mode. When vPpsNew is lower than the Battery voltage, or the Source's primary power is cut off the Sink Shall immediately disconnect its Battery from VBUS. In these situations, the output current could reverse polarity and the Sink is not allowed to source current (see Section 7.2.1, "Behavioral Aspects" and Section 7.2.9, "Robust Sink Operation"). Figure 7.4, "PPS Positive Voltage Transitions" and Figure 7.5, "PPS Negative Voltage Transitions" below show the output voltage behavior of a Programmable Power Supply in response to positive and negative voltage change requests. The parameters vPpsMinVoltage and vPpsMaxVoltage define the lower and upper limits of the PPS range respectively (see Table 10.11, "SPR Programmable Power Supply Voltage Ranges" for required ranges). vPpsMinVoltage corresponds to the Minimum Voltage field in the PPS APDO and vPpsMaxVoltage corresponds to Maximum Voltage field in the PPS APDO. If the Sink negotiates for a new PPS APDO, then the transition between the two PPS APDOs Shall occur as described in Section 7.3.1, "Transitions caused by a Request Message". Figure 7.4 PPS Positive Voltage Transitions vPpsMinVoltage V(2) = 1 + vPpsMinVoltage vPpsMinVoltage V(1) § § Programmable Power Supply Output Range § vPpsSlewPos V(3) = 1+n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § vPpsSlewPos vPpsSlewPos § § § § vPpsValid vPpsNew § § vPpsValid vPpsValid vPpsNew § § vPpsValid Nominal V(2) Nominal V(3) vPpsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) Page 316 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.5 PPS Negative Voltage Transitions Section 7.1.14, "Non-application of VBUS Slew Rate Limits" lists transitions that are exempt from the vPpsSlewNeg and vPpsSlewPos limits. See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage and current DNL step adjustments. 7.1.4.2.2 SPR Programmable Power Supply Current Limit The Programmable Power Supply operating in SPR PPS Mode Shall limit its output current to the Operating Current field value in the RDO when the Sink attempts to draw more current than the Operating Current field value level. The programming step size for the Operating Current is iPpsCLStep. All programming changes of the Operating Current Shall settle to the new Operating Current field value within tPpsCLProgramSettle. The SPR PPS Operating Current regulation accuracy during Current Limit is defined as iPpsCLNew. The minimum programmable Current Limit level is iPpsCLMin. A Source that supports SPR PPS Mode Shall support Current Limit programmability between iPpsCLMin and the Maximum Current value in the SPR PPS APDO. A Source which receives a request for current below iPpsCLMin Should reject the request. A Source that accepts a request for current below iPpsCLMin Shall set its current limit at 1A. The response of an SPR PPS to a load change depends on the Operating mode of the SPR PPS and the magnitude of the load change. These dependencies lead to one of four possible responses of an SPR PPS to any load change. They are differentiated by the value of the PPS Status OMF before and after the load change:  If the PPS Status OMF is cleared both before and after the load change, the SPR PPS responds solely by maintaining the output voltage. The SPR PPS output voltage Shall remain within vPpsValid range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsTransient. The Operating Mode Flag Shall remain cleared during the load change response of the SPR PPS.  If the PPS Status OMF is cleared before the load change and set after the load change, the SPR PPS responds by reducing its output voltage to limit the SPR PPS output current. The SPR PPS output current Shall stay within the iPpsCVCLTransient range once it reaches the iPpsCVCLTransient range. The SPR vPpsMinVoltage V(c) = 1 + vPpsMinVoltage vPpsMinVoltage V(d) § § Programmable Power Supply Output Range § V(b) = 1 + n + vPpsMinVoltage § § 0 Volts vPpsMaxVoltage § § § § § § vPpsValid vPpsNew § § vPpsValid Nominal V(c) Nominal V(b) vPpsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vPpsValid vPpsNew § § vPpsValid § vPpsSlewNeg vPpsSlewNeg vPpsSlewNeg Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 317 PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCVCLTransient. The Operating Mode Flag Shall be set when the SPR PPS load change response settles.  If the PPS Status OMF is set both before and after the load change, the SPR PPS responds by adjusting its output voltage to maintain the output current. The SPR PPS output current Shall stay within the iPpsCLTransient range. The SPR PPS response to the load change Shall settle within the iPpsCLNew tolerance band by the time tPpsCLSettle. The Operating Mode Flag Shall remain set during the load change response of the SPR PPS.  If the PPS Status OMF is set before the load change and cleared after the load change, the PPS responds to the load change by increasing its output voltage to vPpsNew and then maintaining it. The SPR PPS output voltage Shall stay within the vPpsCLCVTransient range. The SPR PPS response to the load change Shall settle within the vPpsNew tolerance band by the time tPpsCLCVTransient. The Operating Mode Flag Shall be cleared when the PPS load change response settles. The SPR PPS Source Shall maintain its output voltage at the value requested in the PPS RDO for all static and dynamic load conditions except when in Current Limit operation. In response to any static or dynamic load condition during Current Limit operation that causes the SPR PPS output voltage to drop below vPpsShutdown the Source May send Hard Reset Signaling and Shall discharge VBUS to vSafe0V then resumes USB Default Operation at vSafe5V. When the Sink attempts to draw more current than the Operating Current in the RDO, the Source Shall limit its output current. The current available from the Source during Current Limit mode Shall meet iPpsCLNew. The Sink May Not reduce its Operating Current request in the RDO when the PPS Status OMF is set. Current limiting Shall be performed by the SPR PPS Source. Sinks that rely on PPS Current Limiting Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The Source Shall Not shutdown or otherwise disrupt the available output power while in Current Limit mode unless another protection mechanism as outlined in Section 7.1.7, "Robust Source Operation" is engaged to protect the Source from damage. An SPR PPS Source that is operating in Current Limit Shall Not change its set-point in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The relationship between SPR PPS programmable output voltage and SPR PPS programmable Current Limit Shall be as shown in Figure 7.6, "SPR PPS Programmable Voltage and Current Limit". The transition between the Constant Voltage mode and the Current Limit mode occurs between points a and b. The PPS Status OMF Shall be set or cleared within this region. In Current Limit mode when the load resistance changes, the output current of the Source Shall stay within iPpsCLNew. The proper behavior is represented by point c. Page 318 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.6 SPR PPS Programmable Voltage and Current Limit 7.1.4.2.3 SPR PPS Constant Power Mode In Constant Power mode (when the PPS Power Limited bit is set) the Source May supply power that exceeds the Source's PDP Rating. Sinks May limit their Operating Current request in the RDO and Shall meet the requirements of Section 7.2.9, "Robust Sink Operation". The tolerances along the Constant Power Curve Shall Not extend into the Guaranteed Capability Area of Figure 7.7, "SPR PPS Constant Power". Current Voltage PPS APDO Min Voltage (max) PPS APDO Max Voltage iPpsCLMin PPS APDO Max Current vPpsNew PPS RDO Operating Current PPS RDO Output Voltage Programmable Voltage Only Region Programmable Voltage & Programmable Current Limit Region Valid Current Limit Response Invalid Current Limit Response iPpsCLNew a Current Limit Flag set Current Limit Flag cleared b c c c Source Disconnect Region vPpsShutdown (min) Point a represents entry into the transition region between Constant Voltage mode and Current Limit mode. Point b represents exit from the transition region between Constant Voltage mode and Current Limit mode. Point c represents the exit from the iPpsCLNew region as the voltage drops below the PPS APDO Min Voltage. The Source May disconnect at any point inside the tolerance range of the minimum voltage defined in the PPS APDO. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 319 Figure 7.7 SPR PPS Constant Power Current Voltage Nominal limits as pr. the APDO Guaranteed operating capability as pr. the APDO Tolerance area for actual voltages (only static tolerances are shown) vPpsNew PDP constant power curve Max APDO Voltage Capabilities when the Power Limited bit is set The figure shows only the steady state after the transition vPpsNew 0A 0V iPpsCLNew (X = PPS APDO Max Current, Y = Prog Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • Prog Voltage = 9V • PPS APDO Max Current = 3 A Coordinate = (3, 9) vPpsNew Min APDO Voltage vPpsNew iPpsCLMin(1A) Min Current Limit PPS APDO Max Current Valid Current Limit Range (X = PDP/PPS APDO Max Current, Y = PPS APDO Max Voltage) Coordinate applies when PPS Power Limited is set Example: • PDP = 27 W • PPS APDO Max Voltage = 11 V Coordinate = (2.45, 11) Page 320 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3 Adjustable Voltage Supply (AVS) 7.1.4.3.1 Adjustable Voltage Supply Voltage Transitions The Adjustable Voltage Supply (AVS) Shall transition VBUS over the defined voltage range in a controlled manner. The Output Voltage value in the AVS RDO defines the nominal value of the AVS output voltage after completing a voltage change and Shall settle within the limits defined by vAvsNew by tAvsSrcTransSmall for steps smaller than or equal to vAvsSmallStep, or else, within the limits defined by vAvsNew by tAvsSrcTransLarge for steps larger than vAvsSmallStep. Any overshoot beyond vAvsNew Shall Not exceed vAvsValid at any time. Any undershoot beyond vAvsNew Shall Not exceed vAvsValid at any time. The AVS output voltage May change in a stepwise or linear manner and the slew rate of either type of change Shall Not exceed vAvsSlewPos for voltage increases or vAvsSlewNeg for voltage decreases. The nominal requested voltage of all linear voltage changes Shall equate to an integer number of LSB changes. An LSB change of the AVS output voltage is defined as vAvsStep. An AVS Shall be able to supply the Negotiated current level as it changes its output voltage to the requested level if the change of output voltage is less than or equal to vAvsSmallStep relative to vAvsNew. All AVS voltage increases Shall result in a voltage that is greater than or equal to the previous AVS output voltage. Likewise, all AVS voltage decreases Shall result in a voltage that is less than or equal to the previous AVS output voltage. Any time the Source enters the AVS range of operation that voltage transition is considered a voltage step larger than vAvsSmallStep. When the AVS voltage steps up or down, a PS_RDY Message Shall be sent within:  tAvsSrcTransLarge after the last bit of the GoodCRC Message following the Accept Message for steps larger than vAvsSmallStep.  tAvsSrcTransSmall after the last bit of the GoodCRC Message following the Accept Message for steps less than or equal to vAvsSmallStep provided the voltage on VBUS has reached vAvsNew. Figure 7.8, "AVS Positive Voltage Transitions" and Figure 7.9, "AVS Negative Voltage Transitions" below show the output voltage behavior of an AVS in response to positive and negative voltage change requests. The parameters vAvsMinVoltage and vAvsMaxVoltage define the lower and upper limits of the AVS range respectively:  For SPR AVS Sources there are two possible voltage ranges where the vAvsMinVoltage is always 9V and vAvsMaxVoltage is either 15V or 20V depending on the Source's PDP. See Table 10.9, "SPR Adjustable Voltage Supply (AVS) Voltage Ranges".  For EPR AVS Sources vAvsMinVoltage corresponds to Minimum Voltage field (always 15V) in the EPR AVS APDO and vAvsMaxVoltage corresponds to Maximum Voltage field in the EPR AVS APDO. See Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" for required ranges. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 321 Figure 7.8 AVS Positive Voltage Transitions Figure 7.9 AVS Negative Voltage Transitions See Section 7.1.8.1, "AVS/PPS Output Voltage Ripple" for output voltage ripple limits. See Section 7.1.8.2, "AVS/PPS DNL Errors and Output Voltage/Current Tolerance" for output voltage DNL step adjustments. vAvsMinVoltage V(2) = 1 + vAvsMinVoltage vAvsMinVoltage V(1) § § Adjustable Voltage Supply Output Range § vAvsSlewPos V(3) = 1+n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § vAvsSlewPos vAvsSlewPos § § § § vAvsValid vAvsNew § § vAvsValid vAvsValid vAvsNew § § vAvsValid Nominal V(2) Nominal V(3) vAvsMaxVoltage V(4) V(2) > V(1) V(3) > V(2) V(4) > V(3) vAvsMinVoltage V(c) = 1 + vAvsMinVoltage vAvsMinVoltage V(d) § § Adjustable Voltage Supply Output Range § V(b) = 1 + n + vAvsMinVoltage § § 0 Volts vAvsMaxVoltage § § § § § § vAvsValid vAvsNew § § vAvsValid Nominal V(c) Nominal V(b) vAvsMaxVoltage V(a) V(b) < V(a) V(d) < V(c) V(c) < V(b) vAvsValid vAvsNew § § vAvsValid § vAvsSlewNeg vAvsSlewNeg vAvsSlewNeg Page 322 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.4.3.2 Adjustable Voltage Supply Current The AVS Shall maintain its output voltage at the value requested in the AVS RDO for all static and dynamic load conditions that do not exceed the Operating Current in the RDO. Unlike the SPR PPS programmable current, the AVS programmable power May range from zero to the PDP. The maximum operating current:  For SPR Sources, the maximum operating current is defined in the SPR Source_Capabilities Message Maximum Current 15V/Maximum Current 20V fields.  For EPR Sources, the maximum operating current has to be calculated as the lower of the PDP field value/Output Voltage or 5A whichever is lower. See Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" 7.1.5 Response to Hard Resets Hard Reset Signaling indicates a communication failure has occurred and the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall drive VBUS to vSafe0V as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". The USB connection May reset during a Hard Reset since the VBUS voltage will be less than vSafe5V for an extended period of time. After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform to the VCONN timing as specified in [USB Type-C 2.4]. A Sink that enters Hard Reset can have cSnkBulkPd present until VBUS drops below vSafe0V. The Source Shall take this into consideration. Device operation during and after a Hard Reset is defined as follows:  Self-powered devices Should Not disconnect from USB during a Hard Reset (see Section 9.1.2, "Mapping to USB Device States").  Self-powered devices operating at more than vSafe5V May Not maintain full functionality after a Hard Reset.  Bus powered devices will disconnect from USB during a Hard Reset due to the loss of their power source. When a Hard Reset occurs the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall start to transition the VBUS voltage to vSafe0V either:  tPSHardReset after the last bit of the Hard Reset Signaling has been received from the Sink or  tPSHardReset after the last bit of the Hard Reset Signaling has been sent by the Source. The Source Shall meet both tSafe5V and tSafe0V relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 323 Figure 7.10 Source VBUS and VCONN Response to Hard Reset VCONN will meet tVCONNDischarge relative to the start of the voltage transition as shown in Figure 7.10, "Source VBUS and VCONN Response to Hard Reset" due to the discharge circuitry in the Cable Plug. VCONN Shall meet tVCONNOn relative to VBUS reaching vSafe5V. Note: tVCONNOn and tVCONNDischarge are defined in [USB Type-C 2.4]. 7.1.6 Changing the Output Power Capability Some USB Power Delivery Negotiations will require the Source to adjust its output power capability without changing the output voltage. In this case the Source Shall be able to supply a higher or lower load current within tSrcReady. 7.1.7 Robust Source Operation 7.1.7.1 Output Over Current Protection Sources Shall implement over current protection to prevent damage from output current that exceeds the current handling capability of the Source. The definition of current handling capability is left to the discretion of the Source implementation and Shall take into consideration the current handling capability of the connector contacts. If the over current protection implementation does not use a Hard Reset or Error Recovery, it Shall Not interfere with the Negotiated VBUS current level. After three consecutive over current events Source Shall go to ErrorRecovery. Sources Should attempt to send Hard Reset Signaling when over current protection engages followed by an Alert Message indicating an OCP event once an Explicit Contract has been established. The over current protection response May engage at either the Port or system level. Systems or ports that have engaged over current protection Should attempt to resume USB Default Operation after determining that the cause of over current is no longer present and May latch off to protect the Port or system. The definition of how to detect if the cause of over current is still present is left to the discretion of the Source implementation. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over current event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over current protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over current. During the over current response and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. Old voltage 0V vSafe0V(max) vSrcNeg(max) t0 tSafe5V tSafe0V tSrcTurnOn vSafe5V(max), VCONN(max) § vVconnDischarge tVconnDischarge tVconnOn tSrcRecover Page 324 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.7.2 Over Temperature Protection Sources Shall implement Over Temperature Protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Source. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Source implementation. In order to avoid reaching an OTP event, Sources May proactively reduce the available power being offered to the Sink, even though these offers might be lower than the Source would be expected to offer during normal thermal operating conditions. Prior to reducing power, the Source Should generate Alert Message indicating an Operating Condition Change and set the Temperature Status bit in the SOP Status Message to Warning (10b). Sources Should attempt to send Hard Reset Signaling when OTP engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The OTP response May engage at either the Port or system level. Systems or ports that have engaged OTP Should attempt to resume USB Default Operation and May latch off to protect the Port or system. The Source Shall Re-negotiate with the Sink after choosing to resume USB Default Operation. The decision of how to Re-negotiate after an over temperature event is left to the discretion of the Source implementation. The Source Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. During the OTP and subsequent system or Port shutdown, all affected Source ports operating with VBUS greater than vSafe5V Shall discharge VBUS to vSafe5V by the time tSafe5V and vSafe0V by the time tSafe0V. 7.1.7.3 vSafe5V Externally Applied to Ports Supplying vSafe5V Safe operation mandates that Power Delivery Sources Shall be tolerant of vSafe5V being present on VBUS when simultaneously applying power to VBUS. Normal USB PD communication Shall be supported when this vSafe5V to vSafe5V connection exists. 7.1.7.4 Detach A USB Detach is detected electrically using CC detection on the USB Type-C connector. When the Source is Detached the Source Shall transition to vSafe0V by tSafe0V relative to when the Detach event occurred. During the transition to vSafe0V the VBUS voltage Shall be below vSafe5V max by tSafe5V relative to when the Detach event occurred and Shall Not exceed vSafe5V max after this time. Sources operating in EPR Mode need to avoid creating large differential voltages at the connector. See Appendix H in the [USB Type-C 2.4] specification for background information. To achieve this, Sources operating in EPR Mode, upon detecting a disconnect, Shall stop sourcing current and minimize VBUS capacitance. There May continue to be current sourced from the Source bulk capacitance, but that Should also be minimized by disconnecting as much of the Source bulk capacitance as possible. For example, the Source can stop sourcing from the Power Supply and the C1 portion of the Source bulk capacitance in Figure 7.1, "Placement of Source Bulk Capacitance" by disabling the Ohmic Interconnect switch. The Source Should detect the disconnect, stop sourcing current, and minimize the VBUS capacitance as quickly as practical. If this is done after the CC contacts disconnect and before the VBUS contacts disconnect there is less risk of large differential voltages at the connector. Note: A USB-PD transmission by the Source during a disconnect event will delay disconnect detection by the Source. 7.1.7.5 Output Voltage Limit The output voltage of Sources Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid or vAvsNew, vAvsValid as determined by the Negotiated VBUS value. Sources Shall meet applicable safety and regulatory requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 325 7.1.8 Output Voltage Tolerance and Range After a voltage transition is complete (i.e., after tSrcReady) and during static load conditions the Source output voltage Shall remain within the vSrcNew or vSafe5V limits as applicable. The ranges defined by vSrcNew and vSafe5V account for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e., after tSrcReady) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vSrcValid. The amount of time the Source output voltage can be in the band between either vSrcNew or vSafe5V and vSrcValid Shall Not exceed tSrcTransient. Refer to Table 7.23, "Source Electrical Parameters" for the output voltage tolerance specifications. Figure 7.11, "Application of vSrcNew and vSrcValid limits after tSrcReady" illustrates the application of vSrcNew and vSrcValid after the voltage transition is complete. The vSrcNew and vSrcValid limits Shall Not apply to VBUS during the VBUS discharge and switchover that occurs during a Fast Role Swap as described in Section 7.1.13, "Fast Role Swap". Figure 7.11 Application of vSrcNew and vSrcValid limits after tSrcReady The Source output voltage Shall be measured at the connector receptacle. The stability of the Source Shall be tested in 25% load step increments from minimum load to maximum load and also from maximum load to minimum load. The transient behavior of the load current is defined in Section 7.2.6, "Transient Load Behavior". The time between each step Shall be sufficient to allow for the output voltage to settle between load steps. In some systems it might be necessary to design the Source to compensate for the voltage drop between the output stage of the power supply electronics and the receptacle contact. The determination of whether compensation is necessary is left to the discretion of the Source implementation. 7.1.8.1 AVS/PPS Output Voltage Ripple The AVS/PPS output voltage ripple is expected to exceed the magnitude of one or more LSB as show in the Figure 7.12, "Expected AVS/PPS Ripple Relative to an LSB". Sink Load I1 vSrcNew(typ) tSrcReady iLoadStepRate vSrcValid(max) vSrcValid(min) vSrcNew(max) vSrcNew(min) tSrcTransient window у tSrcTransient windows у у iLoadReleaseRate Sink Load I2 Page 326 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.12 Expected AVS/PPS Ripple Relative to an LSB 7.1.8.2 AVS/PPS DNL Errors and Output Voltage/Current Tolerance The PPS voltage and current discrete LSB steps have a DNL tolerance as shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode" below. In absolute terms the step size of the LSB for both voltage and current is defined by vPpsStep/vAvsStep for voltage and iPpsCLStep for current. Several examples of Valid LSB steps are shown in Figure 7.13, "Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode":  The upper end of the DNL error (+1 LSB) shows the case where one step is effectively skipped.  The lower end of the DNL error (-1 LSB) shows the case where the voltage or current set-point remained the same. The ideal scenario for the DNL error (=0) matches the typical step size for the voltage or current. The intent of DNL is to guarantee that changes to the voltage/current have the correct directionality, and that the maximum step size is clearly defined. Note: The Source Should avoid scenarios where multiple consecutive steps have errors close to the Maximum and Minimum DNL. time voltage +1 LSB +1 LSB Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 327 Figure 7.13 Allowed DNL errors and tolerance of Voltage and Current in AVS/PPS mode 7.1.8.3 Programmable Power Supply Output Voltage Tolerance and Range After a voltage transition of a Programmable Power Supply is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vPpsNew limits. The range defined by vPpsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tPpsSrcTransSmall or tPpsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vPpsValid. The amount of time the Source output voltage can be in the band between vPpsNew and vPpsValid Shall Not exceed tPpsTransient. 7.1.8.4 Adjustable Voltage Supply Output Voltage tolerance and Range After a voltage transition of an AVS is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during static load conditions the Source output voltage Shall remain within the vAvsNew limits. The range defined by vAvsNew accounts for DC regulation accuracy, line regulation, load regulation and output ripple. After a voltage transition is complete (i.e. after tAvsSrcTransSmall or tAvsSrcTransLarge) and during transient load conditions the Source output voltage Shall Not go beyond the range specified by vAvsValid. The amount of time the Source output voltage can be in the band between vAvsNew and vAvsValid Shall Not exceed tAvsTransient. Code Voltage, Current 1 LSB DNL < 0 LSB Max DNL = 1 LSB vPpsNew,vAvsNew, iPpsNew (max) vPpsNew,vAvsNew, iPpsNew (min) vPpsNew,vAvsNew, iPpsNew DNL = -1 LSB Page 328 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.9 Charging and Discharging the Bulk Capacitance on VBUS The Source Shall charge and discharge the bulk capacitance on VBUS whenever the Source voltage is Negotiated to a different value. The charging or discharging occurs during the voltage transition and Shall Not interfere with the Source's ability to meet tSrcReady. 7.1.10 Swap Standby for Sources Sources and Sinks of a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Source after the Source power supply has discharged the bulk capacitance on VBUS to vSafe0V as part of the Power Role Swap transition. While in Swap Standby:  The Source Shall Not drive VBUS that is therefore expected to remain at vSafe0V.  Any discharge circuitry that was used to achieve vSafe0V Shall be removed from VBUS.  The Dual-Role Power Port Shall be configured as a Sink.  The USB connection Shall Not reset even though vSafe5V is no longer present on VBUS (see Section 9.1.2, "Mapping to USB Device States"). The PS_RDY Message associated with the Source being in Swap Standby Shall be sent after the VBUS drive is removed. The time for the Source to transition to Swap Standby Shall Not exceed tSrcSwapStdby. Upon entering Swap Standby, the Source has relinquished its Power Role as Source and is ready to become the New Sink. The transition time from Swap Standby to being the New Sink Shall be no more than tNewSnk. The New Sink May start using power after the new Source sends the PS_RDY Message. 7.1.11 Source Peak Current Operation A Source that has the Fixed Supply PDO or AVS APDO Peak Current bits set to 01b, 10b and 11b Shall be designed to support one of the overload Capabilities defined in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability" respectively. The overload conditions are bound in magnitude, duration and duty cycle as listed in Table 6.10, "Fixed Power Source Peak Current Capability" or Table 6.16, "EPR AVS Power Source Peak Current Capability". Sources are not required to support continuous overload operation. When overload conditions occur, the Source is allowed the range of vSrcPeak (instead of vSrcNew) relative to the nominal value (see Figure 7.14, "Source Peak Current Overload"). When the overload capability is exceeded, the Source is expected take whatever action is necessary to prevent electrical or thermal damage to the Source. The Source May send a new Source_Capabilities Message with the Fixed Supply PDO or AVS APDO Peak Current bits set to 00b to prohibit overload operation even if an overload capability was previously Negotiated with the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 329 Figure 7.14 Source Peak Current Overload 7.1.12 Source Capabilities Extended Parameters Implementers can choose to make available certain characteristics of a PDUSB Source as a set of Static and/or dynamic parameters to improve interoperability between external power sources and portable computing devices. The complete list of reportable Static parameters is described in full in Section 6.5.1, "Source_Capabilities_Extended Message" and listed in Figure 6.37, "Source_Capabilities_Extended Message". The subset of parameters listed below directly represent Source Capabilities and are described in the rest of this section.  Voltage Regulation.  Holdup Time.  Compliance.  Peak Current.  Source Inputs.  Batteries. 7.1.12.1 Voltage Regulation Field The power consumption of a device can change dynamically. The ability of the Source to regulate its voltage output might be important if the device is sensitive to fluctuations in voltage. The Voltage Regulation bit field is used to convey information about the Sources output regulation and tolerance to various load steps. 7.1.12.1.1 Load Step Slew Rate The default load step slew rate is established at 150mA/µs. A Source Shall meet the following requirements under the load step reported in the Source_Capabilities_Extended Message:  The Source Shall maintain VBUS regulation within the vSrcValid range.  The noise on the CC line Shall remain below vNoiseIdle and vNoiseActive. Sink Port Current Source Port Voltage vSrcNew(max)/ vSrcPeak(max) Nominal Voltage vSrcNew(min) vSrcPeak(min) IOC level as requested in the Operating Current field of an RDO % level with respect to IOC as advertised in the Peak Current field of Fixed Supply PDO Additional operating range for Fixed Supply that supports overload capability Operating range for supply that DOES NOT support overload capability Page 330 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Test conditions require a change in both positive and negative load steps from 1Hz to 5000Hz, up to the Advertised Load Step Magnitude of the full load output including from both 10 mA and 10% initial load. The Source Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks" under all load conditions. 7.1.12.1.2 Load Step Magnitude The default load step magnitude rate Shall be 25% of IoC. The Source May report higher capability tolerating a load step of 90% of IoC. 7.1.12.2 Holdup Time Field The Holdup Time field Shall return a numeric value of the number of milliseconds the output voltage stays in regulation upon a short interruption of the AC Supply. An AC Supplied Source Shall report its holdup time in this field. The holdup time is measured with the load at rated maximum, with the AC Supply at 115VAC rms and 60Hz (or at 230VAC rms and 50Hz for a Source that does not support 115VAC AC Supply). The reported time describes the minimum length of time from the last completed AC Supply input cycle (zero-degree phase angle) until when the output voltage decays below vSrcValid (min). Sources are recommended to support a minimum of 3ms and are preferred to support over 10 milliseconds holdup time (equivalent to a half cycle drop from the AC Supply). See Figure 7.15, "Holdup Time Measurement". Figure 7.15 Holdup Time Measurement 7.1.12.3 Compliance Field An SPR Source claiming LPS, PS1 or PS2 compliance (see [IEC 62368-1]) Shall report its Capabilities in the Compliance field. Since the SPR Source May have several potential output voltage and current settings, every SPR Source supply (each indicated by a PDO) Shall be compliant to LPS requirements. Note: According to the requirements of [IEC 60950-1] and/or [IEC 62368-3], a device tested and certified with an LPS Source (SPR Source or EPR Source operating in SPR Mode) is prohibited from using a non-LPS Source (EPR Source operating in EPR Mode). Alternatively, [IEC 62368-1], classifies power sources according to their maximum, constrained power output (15watts or 100watts). 7.1.12.4 Peak Current The Source reports its ability to source peak current delivery in excess of the Negotiated amount in the Peak Current field. The duration of peak current Shall be followed by a current consumption below the Operating Current (IoC) in order to maintain average power delivery below the IoC current. vSrcValid(min) Hold Up Time у VBUS AC mains voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 331 A Source May have greater capability to source peak current than can be reported using the Peak Current field in the Fixed Supply PDO or AVS APDO. In this case the Source Shall report its additional capability in the Peak Current1/Peak Current2/Peak Current3 fields in the Source_Capabilities_Extended Message. Each overload period Shall be followed by a period of reduced current draw such that the rolling average current over the Overload Period field value with the specified Duty Cycle field value (see Section 6.5.1.10, "Peak Current Field") Shall Not exceed the Negotiated current. This is calculated as: Period of reduced current = (1 - value in Duty Cycle field/100) * value in Overload Period field 7.1.12.5 Source Inputs The Source Inputs field identifies the possible inputs that provide power to the Source. Note: Some Sources are only powered by a Battery (e.g., an automobile) rather than the more common AC Supply. 7.1.12.6 Batteries The Number of Batteries/Battery Slots field Shall report the number of Batteries the Source supports. The Source Shall independently report the number of Hot Swappable Batteries and the number of Fixed Batteries. 7.1.13 Fast Role Swap A Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port supporting DRP as shown in Figure 7.16, "VBUS Power during Fast Role Swap". Figure 7.16 VBUS Power during Fast Role Swap When the power source connected to the Hub UFP stops sourcing power and VBUS at the Hub DRP connector discharges below vSrcValid(min), if VBUS has been Negotiated to a higher voltage than vSafe5V, or vSafe5V (min) the Fast Role Swap Request Shall be sent from the Hub DRP to the Host DRP and the Hub DRP Shall sink power. In the Fast Role Swap use case, the Hub DRP behaves like a bidirectional power path. The Hub DRP Shall Not enable VBUS discharge circuitry when changing operation from Initial Source to New Sink. The Hub DFP Port(s) Shall support default USB Type-C Current (see [USB Type-C 2.4]) until a new Explicit Contract is Negotiated. After sending the Fast Role Swap Request and while VBUS > vSafe5V (min), the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. The New Sink Shall Not draw more than iSnkStdby from VBUS until tSnkFRSwap after it has started sending the Fast Role Swap Request or VBUS has fallen below vSafe5V (min). The tSnkFRSwap time Shall start at the beginning of the Fast Role Swap Request or when VBUS falls below vSafe5V (min), whichever comes later. After waiting for tSnkFRSwap, the New Sink Shall Not draw more than iNewFrsSink until the New Source has applied its Rp. After the New Source has applied its Rp, the New Sink Shall be limited to USB Type-C Current (see [USB Type-C 2.4]) in an Implicit Contract until a new Explicit Contract is Negotiated. All Sink requirements Shall apply to the New Sink after the Fast Role Swap is complete. The Fast Role Swap response of the Host DRP is described in Section 7.2.10, "Fast Role Swap" since the Host DRP is operating as the Initial Sink prior to the Fast Role Swap. After the VBUS voltage level at the Hub DRP connector drops below vSafe5V a PS_RDY Message Shall be sent to the Host DRP as shown in the Fast Role Swap transition diagram of Section 7.3.4, "Transitions Caused by Fast Role Swap". USB PD Capable Hub DRP UFP DFP Power Source Bus Powered Accessory USB PD Capable Host DRP Power flow before the Fast Role Swap Power flow after the Fast Role Swap Page 332 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.17, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min)" and Figure 7.18, "VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min)" show the VBUS detection and timing for the New Source during a Fast Role Swap after the Fast Role Swap Request has been received. The New Source May turn on the VBUS output switch once VBUS is below vSafe5V (max). In this case, the New Source prevents VBUS from falling below vSafe5V (min). The new source Shall turn on the VBUS output switch within tSrcFRSwap of falling below vSafe5V (min). VBUS might have started at vSafe5V or at higher voltage. When the Fast Role Swap Request is detected, VBUS could therefore be either above vSafe5V (max), within the vSafe5V range, or below vSafe5V (min). If the Fast Role Swap Request is detected when VBUS is below vSafe5V (min), then the new source Shall turn on the VBUS output switch within tSrcFRSwap of detecting the Fast Role Swap Request. In this case, the maximum time from the beginning of the Fast Role Swap Request to VBUS being sourced May be tSrcFRSwap (max) + tFRSwapRx (max). Figure 7.17 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) > vSafe5V(min) Figure 7.18 VBUS detection and timing during Fast Role Swap, initial VBUS (at new source) < vSafe5V(min) 7.1.14 Non-application of VBUS Slew Rate Limits Scenarios where vSrcSlewPos and vPpsSlewPos VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When first applying VBUS after an Attach.  When applying VBUS as part of a Power Role Swap to Source Power Role.  When increasing VBUS from vSafe0V to vSafe5V during a Hard Reset.  During a Fast Role Swap when the Initial Sink applies VBUS. Old Voltage 0V vSafe5V(min) tSrcFRSwap vSafe5V(max) § New Source may turn on at any time after VBUS falls below vSafe5V(max) VBUS Old Source detects power loss and signals Fast Role Swap Old Voltage 0V vSafe5V(min) tSrcFRSwap VBUS is below vSafe5V(min) before FRS signal is finished Old Source detects power loss and signals Fast Role Swap tFRSwapRx (max) VBUS at new Source CC New Source may turn on after detecting Fast Role Swap signal Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 333 Scenarios where vSrcSlewNeg and vPpsSlewNeg VBUS slew rate limits do not apply and VBUS May transition faster than specified are as follows:  When discharging VBUS to vSafe0V during a Hard Reset.  When discharging VBUS to vSafe0V as part of a Power Role Swap to Sink Power Role.  When discharging VBUS to vSafe0V after a Detach.  During a Fast Role Swap when the VBUS power source connected to the Hub UFP stops sourcing power. 7.1.15 VCONN Power Cycle 7.1.15.1 UFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the UFP is the VCONN Source, the following steps Shall be followed:  Following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message, the UFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type- C 2.4]) within tVCONNZero.  When VCONN is below vRaReconnect, the UFP Shall send a PS_RDY Message. Note: If the UFP was not sourcing VCONN, it still sends the PS_RDY Message.  The DFP Shall wait tVCONNReapplied following the last bit of the GoodCRC Message acknowledging the PS_RDY Message before sourcing VCONN. The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.19, "Data Reset UFP VCONN Power Cycle" below illustrates the UFP VCONN Power Cycle process. Figure 7.19 Data Reset UFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied PS_RDY (UFP) UFP DFP Page 334 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.1.15.2 DFP VCONN Power Cycle The Data Reset process requires the DFP to be the VCONN Source by the end of the process. In the case where the DFP is the VCONN Source, the following steps Shall be followed: 1) If the DFP sent the Data_Reset Message and is sourcing VCONN then it Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero of the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 2) If the UFP sent the Data_Reset Message then the DFP Shall turn off VCONN and ensure it is below vRaReconnect (see [USB Type-C 2.4]) within tVCONNZero following the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Data_Reset Message. 3) When VCONN is below vRaReconnect, the DFP Shall wait tVCONNReapplied before sourcing VCONN. 4) The DFP Shall ensure VCONN is within vVCONNValid (see [USB Type-C 2.4]) within tVCONNValid. Figure 7.20, "Data Reset DFP VCONN Power Cycle" below illustrates the DFP VCONN Power Cycle process. Figure 7.20 Data Reset DFP VCONN Power Cycle 0V Accept (DFP/UFP) vVCONNValid vRaReconnect tVCONNZero tVCONNValid tVCONNReapplied UFP DFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 335 7.2 Sink Requirements 7.2.1 Behavioral Aspects A PDUSB Sink exhibits the following behaviors:  Shall Not draw more than [USB Type-C 2.4] USB Type-C Current from VBUS while in a Default Contract or Implicit Contract.  Shall follow the requirements as specified in Section 7.1.5, "Response to Hard Resets" when Hard Reset Signaling is received.  Shall control VBUS in-rush current when increasing current consumption according to [USB 2.0] or [USB 3.2] as appropriate. 7.2.2 Sink Bulk Capacitance The Sink bulk capacitance consists of C3 and C4 as shown in Figure 7.21, "Placement of Sink Bulk Capacitance". The Ohmic Interconnect might consist of PCB traces for power distribution or power switching devices. The Ohmic Interconnect is expected to be part of an input Over Voltage Protection (Sink OVP) circuit implemented by the Sink as described in Section 7.2.9.2, "Input Over Voltage Protection" to protect against excessive VBUS input voltage. A Sink Shall implement OVP. The Sink Shall Not rely on the Source output voltage limit for its input OVP. The capacitance might be a single capacitor, a capacitor bank or distributed capacitance. An upper bound of cSnkBulkPd Shall Not be exceeded so that the transient charging, or discharging, of the total bulk capacitance on VBUS can be accounted for during voltage transitions. The Sink bulk capacitance that is within the cSnkBulk max or cSnkBulkPd max limits is allowed to change to support a newly Negotiated power level. The capacitance can be changed when the Sink enters Sink Standby or during a voltage transition or when the Sink begins to operate at the new power level. Changing the Sink bulk capacitance Shall Not cause a transient current on VBUS that violates the present Contract. During a Power Role Swap the Default Sink Shall transition to Swap Standby before operating as the New Source. Any change in bulk capacitance required to complete the Power Role Swap Shall occur during Swap Standby. Figure 7.21 Placement of Sink Bulk Capacitance 7.2.3 Sink Standby The Sink Shall transition to Sink Standby before a positive voltage transition of VBUS. During Sink Standby the Sink Shall reduce the current drawn to iSnkStdby. This allows the Source to manage the voltage transition as well as supply sufficient operating current to the Sink to maintain PD operation during the transition. The Sink Shall complete this transition to Sink Standby within tSnkStdby after evaluating the Accept Message from the Source. The transition when returning to Sink operation from Sink Standby Shall be completed within tSnkNewPower. The iSnkStdby requirement Shall only apply if the Sink current draw is higher than this level. See Section 7.3, "Transitions" for details. GND SHIELD VBUS ... Data Lines C3 GND SHIELD VBUS ... Data Lines SINK CABLE C4 Load Sink Bulk Capacitance Ohmic Interconnect OVP Page 336 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.3.1 Programmable Power Supply Sink Standby A Sink is not required to transition to Sink Standby when operating within the Negotiated PPS APDO. A Sink May consume the Operating Current value in the PPS RDO during PPS output voltage changes. However, prior to operating the SPR PPS in Current Limit, the Sink Shall program the PPS Operating Voltage to the lowest practical level that satisfies the Sink load requirement. Doing so will minimize the inrush current that occurs when the transition to Current Limit occurs. When operating with an SPR PPS Source that is in Current Limit, the Sink Shall Not change its load in a manner that exceeds iPpsCLLoadStepRate or iPpsCLLoadReleaseRate. The load change magnitude Shall Not request a change to the Current Limit set-point that exceeds iPpsCLLoadStep. If the Sink Negotiates for a new PPS APDO, that is expected to increase VBUS voltage, then the Sink Shall transition to Sink Standby while changing between PPS APDOs as described in Section 7.3.1, "Transitions caused by a Request Message". 7.2.4 Suspend Power Consumption When Source has set its USB Suspend Supported flag (see Section 6.4.1.2.1.2, "USB Suspend Supported"), a Sink Shall go to the lowest power state during USB suspend. The lowest power state Shall be pSnkSusp or lower for a PDUSB Peripheral and pHubSusp or lower for a PDUSB Hub. There is no requirement for the Source voltage to be changed during USB suspend. 7.2.5 Zero Negotiated Current When a Sink Requests zero current as part of a power Negotiation with a Source, the Sink Shall go to the lowest power state, pSnkSusp or lower, where it can still communicate using PD signaling. 7.2.6 Transient Load Behavior When a Sink's operating current changes due to a load step, load release or any other change in load level, the positive or negative overshoot of the new load current Shall Not exceed the range defined by iOvershoot. For the purposes of measuring iOvershoot the new load current value is defined as the average steady state value of the load current after the load step has settled. The rate of change of any shift in Sink load current during normal operation Shall Not exceed iLoadStepRate (for load steps) and iLoadReleaseRate (for load releases) as measured at the Sink receptacle. The Sink's operating current Shall Not change faster than the value reported in the Source's Load Step Slew Rate in its Voltage Regulation bit field and Shall ensure that PD Communications meet the transmit and receive masks as specified in Section 5.8.2, "Transmit and Receive Masks". 7.2.7 Swap Standby for Sinks The Sink functionality in a Dual-Role Power Port Shall support Swap Standby. Swap Standby occurs for the Sink after evaluating the Accept Message from the Source during a Power Role Swap. While in Swap Standby the Sink's current draw Shall Not exceed iSnkSwapStdby from VBUS and the Dual-Role Power Port Shall be configured as a Source after VBUS has been discharged to vSafe0V by the existing Initial Source. The Sink's USB connection Should Not be reset even though vSafe5V is not present on the VBUS conductor (see Section 9.1.2, "Mapping to USB Device States"). The time for the Sink to transition to Swap Standby Shall be no more than tSnkSwapStdby. When in Swap Standby the Sink has relinquished its Power Role as Sink and will prepare to become the New Source. The transition time from Swap Standby to New Source Shall be no more than tNewSrc. 7.2.8 Sink Peak Current Operation Sinks Shall only make use of a Source overload capability when the corresponding Fixed Supply PDO Peak Current (see Section 6.4.1.2.1.8, "Peak Current") or AVS APDO Peak Current (see Section 6.4.1.2.4.3.2, "Peak Current") bits are set to 01b, 10b and 11b. Sinks Shall manage thermal aspects of the overload event by not exceeding the average Negotiated output of a Fixed Supply or AVS that supports Peak Current operation. Sinks that depend on the Peak Current capability for enhanced system performance Shall also function correctly when Attached to a Source that does not offer the Peak Current capability or when the Peak Current capability has been inhibited by the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 337 7.2.9 Robust Sink Operation 7.2.9.1 Sink Bulk Capacitance Discharge at Detach When a Source is Detached from a Sink, the Sink Shall continue to draw power from its input bulk capacitance until VBUS is discharged to vSafe5V or lower by no longer than tSafe5V from the Detach event. This safe Sink requirement Shall apply to all Sinks operating with a Negotiated VBUS level greater than vSafe5V and Shall apply during all low power and high-power operating modes of the Sink. If the Detach is detected during a Sink low power state, such as USB Suspend, the Sink can then draw as much power as needed from its bulk capacitance since a Source is no longer Attached. In order to achieve a successful Detach detect based on VBUS voltage level droop, the Sink power consumption Shall be high enough so that VBUS will decay below vSrcValid(min) well within tSafe5V after the Source bulk capacitance is removed due to the Detach. Once adequate VBUS droop has been achieved, a discharge circuit can be enabled to meet the safe Sink requirement. To illustrate the point, the following set of Sink conditions will not meet the safe Sink requirement without additional discharge circuitry:  Negotiated VBUS = 20V.  Maximum allowable supplied VBUS voltage = 21.55V.  Maximum bulk capacitance = 30µF.  Power consumption at Detach = 12.5mW. When the Detach occurs (hence removal of the Source bulk capacitance) the 12.5mW power consumption will draw down the VBUS voltage from the worst-case maximum level of 21.55V to 17V in approximately 205ms. At this point, with VBUS well below vSrcValid (min) an approximate 100mW discharge circuit can be enabled to increase the rate of Sink bulk capacitance discharge and meet the safe Sink requirement. The power level of the discharge circuit is dependent on how much time is left to discharge the remaining voltage on the Sink bulk capacitance. If a Sink has the ability to detect the Detach in a different manner and in much less time than tSafe5V, then this different manner of detection can be used to enable a discharge circuit, allowing even lower power dissipation during low power modes such as USB Suspend. In most applications, the safe Sink requirement will limit the maximum Sink bulk capacitance well below the cSnkBulkPd limit. A Detach occurring during Sink high power operating modes must quickly discharge the Sink bulk capacitance to vSafe5V or lower as long as the Sink continues to draw adequate power until VBUS has decayed to vSafe5V or lower. 7.2.9.2 Input Over Voltage Protection Sinks Shall implement input Over-Voltage Protection (OVP) to prevent damage from input voltage that exceeds the voltage handling capability of the Sink. The definition of voltage handling capability is left to the discretion of the Sink implementation. The over voltage response of Sinks Shall Not interfere with normal PD operation and Shall account for vSrcNew, vSrcValid or vPpsNew, vPpsValid as determined by the Negotiated VBUS value. SPR Sinks Should tolerate input voltages as high as vSprMax and Shall meet applicable safety requirements if vSprMax is exceeded. Likewise, EPR Sinks Should tolerate input voltages as high as vEprMax and Shall meet applicable safety requirements if vEprMax is exceeded. Sinks Should attempt to send Hard Reset Signaling when OVP engages followed by an Alert Message indicating an OVP event once an Explicit Contract has been established. The OVP response May engage at either the Port or system level. Systems or ports that have engaged OVP Shall resume USB Default Operation when the Source has re- established vSafe5V on VBUS. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an OVP event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if OVP continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over voltage. Page 338 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.2.9.3 Over Temperature Protection Sinks Shall implement over temperature protection (OTP) to prevent damage from temperature that exceeds the thermal capability of the Sink. The definition of thermal capability and the monitoring locations used to trigger the over temperature protection are left to the discretion of the Sink implementation. Sinks Shall attempt to send Hard Reset Signaling when over temperature protection engages followed by an Alert Message indicating an OTP event once an Explicit Contract has been established. The over temperature protection response May engage at either the Port or system level. Systems or ports that have engaged over temperature protection Should attempt to resume USB Default Operation after sufficient cooling is achieved and May latch off to protect the Port or system. The definition of sufficient cooling is left to the discretion of the Sink implementation. The Sink Shall be able to Re-negotiate with the Source after resuming USB Default Operation. The decision of how to respond to Re-negotiation after an over temperature event is left to the discretion of the Sink implementation. The Sink Shall prevent continual system or Port cycling if over temperature protection continues to engage after initially resuming either USB Default Operation or Re-negotiation. Latching off the Port or system is an acceptable response to recurring over temperature. 7.2.9.4 Over Current Protection Sinks that operate with a Programmable Power Supply Shall implement their own internal current protection mechanism to protect against internal VBUS current faults as well as erratic Source current regulation. The Sink Shall never draw higher current than the Maximum Current value in the PPS APDO. 7.2.10 Fast Role Swap As described in Section 7.1.13, "Fast Role Swap" a Fast Role Swap limits the interruption of VBUS power to a bus powered accessory connected to a Hub DFP that has a UFP Attached to a power source and a DRP Attached to a Host Port that supports DRP. This configuration is shown in Figure 7.16, "VBUS Power during Fast Role Swap". The Host DRP, upon establishing an Explicit Contract, Shall query the Initial Source's Sink Capabilities to determine whether the Initial Source supports Fast Role Swap, and what level of current it requires. If the Sink_Capabilities Message received from the Initial Source has at least one of the Fast Role Swap required USB Type-C Current bits set, and the Host DRP is able to source the requested current at 5V, the Host DRP May arm itself for Fast Role Swap. If the Host DRP has not queried the Sink Capabilities from the Initial Source, or if the Sink_Capabilities Message reports no Fast Role Swap support or a current that is beyond what the Host DRP is able or willing to source in the event of a Fast Role Swap, the Host DRP Shall Not arm itself for Fast Role Swap and Shall Ignore any Fast Role Swap Requests that are detected. When the Host DRP that supports Fast Role Swap detects the FFast Role Swap Request, the Host DRP Shall stop sinking current and Shall be ready and able to source vSafe5V if the residual VBUS voltage level at the Host DRP connector is greater than vSafe5V. When the residual VBUS voltage level at the Host DRP connector discharges below vSafe5V(min) the Host DRP as the New Source Shall supply vSafe5V to the Hub DRP within tSrcFRSwap. The Host DRP Shall Not enable VBUS discharge circuitry when changing Power Roles from Initial Sink to New Source. The New Source Shall supply vSafe5V at USB Type-C Current (see [USB Type-C 2.4]) at the value Advertised in the Fast Role Swap required USB Type-C Current field (see Section 6.4.1.3.1.6, "Fast Role Swap USB Type-C Current"). All Source requirements Shall apply to the New Source after the Fast Role Swap is complete The Fast Role Swap response of the Hub DRP is described in Section 7.1.13, "Fast Role Swap" since the Hub DRP is operating as the Initial Source prior to the Fast Role Swap. After the Host DRP is providing VBUS power to the Hub DRP, a PS_RDY Message Shall be sent to the Hub DRP as defined by the Fast Role Swap Request and the AMS detailed in Section 7.3.4, "Transitions Caused by Fast Role Swap". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 339 7.3 Transitions The following sections illustrate the power supply's response to various types of Negotiations. The Negotiations are triggered by certain Messages or Signaling. It provides examples of the transitions and is organized around each of the Messages and Signals that result in a response from the power supply. The response to a Message or Signal can result in different transitions depending upon the power supply's starting conditions and the requested change.  Transitions caused by a Request Message:  Generic transition between (A)PDO s:  Increase the current.  Increase the voltage.  Increase the voltage and the current.  Increase the voltage and decrease the current.  Decrease the voltage and increase the current.  Decrease the voltage and the current.  No change in Current or voltage.  Transitions within the same PDO (Fixed Supply, Battery Supply, Variable Supply):  Increase the current.  Decrease the current.  No change in current.  Transitions within the same PPS APDO:  Increasing the Programmable Power Supply (PPS) voltage.  Decreasing the Programmable Power Supply (PPS) voltage.  Increasing the Programmable Power Supply (PPS) Current.  Decreasing the Programmable Power Supply (PPS) Current.  Same Request Programmable Power Supply (PPS).  Transitions within the same AVS APDO:  Increasing the Adjustable Voltage Supply (AVS) voltage  Decreasing the Adjustable Voltage Supply (AVS) voltage  Same Request Adjustable Voltage Supply (AVS)  Transitions caused by the PR_Swap Message:  Source requests a Power Role Swap  Sink requests a Power Role Swap  Transitions caused by Hard Reset Signaling:  Source issues Hard Reset Signaling.  Sink issues Hard Reset Signaling.  Transitions caused by the Fast Role Swap Request:  Source asserts Rd at its preferred [USB Type-C 2.4] current. Page 340 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1 Transitions caused by a Request Message This section describes transitions that are caused by a Request Message. 7.3.1.1 Changing the Source between Different (A)PDOs In these transition descriptions the term (A)PDO is used to describe any Power Data Object, regardless of whether it is a PDO or an APDO in the Capabilities Message. This section describes transitions in response to a Request Message:  From one (A)PDO to another (A)PDO  From an Implicit Contract to an Explicit Contract  From [USB Type-C 2.4]operation to the First Explicit Contract These transitions usually result in a voltage change but is not required. The interaction of the Device Policy Manager, the Port Policy Engine and the Power Supply that Shall be followed when increasing the current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current" and Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The Source voltage as the transition starts Shall be any voltage within the Valid VBUS range of the previous Source PDO or APDO. The Source voltage after the transition is complete Shall be any voltage within the Valid VBUS range of the New Source PDO or APDO. The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current" and Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In this figure, the Sink has previously sent a Request Message to the Source. The voltage is considered to increase if the change from VOLD to VNEW is greater than vSmallStep. The determination Shall be based on the nominal (A)PDO voltage before and after, unless either (A)PDO is Battery Supply or Variable Supply when the worst case of the following is assumed in making this determination.  Minimum voltage to voltage.  Minimum voltage to Maximum voltage.  Voltage to Maximum voltage. The following sections begin with a description of the generic process followed by more specific examples of the most common transitions. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 341 7.3.1.1.1 Examples of changes from one (A)PDO to another (A)PDO The seven examples of (A)PDO change transitions below illustrate the most common transitions. 7.3.1.1.1.1 Increasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage is shown in Figure 7.22, "Transition Diagram for Increasing the Voltage". The sequence that Shall be followed is described in Table 7.1, "Sequence Description for Increasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.22, "Transition Diagram for Increasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 342 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.22 Transition Diagram for Increasing the Voltage t3 t1 t2 Source VOLD Source VNEW Source × V 4 3 7 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply 8 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,2/' Sink ” IOLD ” IOLD ” IOLD Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) VNEW I1 ... § Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 343 Table 7.1 Sequence Description for Increasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 344 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.2 Increasing the Voltage and Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and current is shown in Figure 7.23, "Transition Diagram for Increasing the Voltage and Current". The sequence that Shall be followed is described in Table 7.2, "Sequence Diagram for Increasing the Voltage and Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.23, "Transition Diagram for Increasing the Voltage and Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 345 Figure 7.23 Transition Diagram for Increasing the Voltage and Current t3 Source VOLD Source VNEW Source × V × I 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ”INEW Sink to Sink Standby Sink iSnkStdBy Sink Standby to Sink VOLD VNEW 3 7 I1 § ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) t2 t1 Page 346 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.2 Sequence Diagram for Increasing the Voltage and Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out, the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 347 7.3.1.1.1.3 Increasing the Voltage and Decreasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while increasing the voltage and decreasing the current is shown in Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current". The sequence that Shall be followed is described in Table 7.3, "Sequence Description for Increasing the Voltage and Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.24, "Transition Diagram for Increasing the Voltage and Decreasing the Current", the Sink has previously sent a Request Message to the Source. Page 348 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.24 Transition Diagram for Increasing the Voltage and Decreasing the Current t3 t1 Source VOLD Source VNEW Source × V ØI 4 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW I1 Sink to Sink Standby Sink Standby to Sink Sink iSnkStdBy VNEW VOLD 3 7 ... 8 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current I1 ” iSnkStdBy + cSnkBulkPd( VBUS/ t) § t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 349 Table 7.3 Sequence Description for Increasing the Voltage and Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to reduce current drawn to iSnkStdby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 8 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t3) depends on the magnitude of the load change. Page 350 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.4 Decreasing the Voltage and Increasing the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and increasing the current is shown in Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current". The sequence that Shall be followed is described in Table 7.4, "Sequence Description for Decreasing the Voltage and Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.25, "Transition Diagram for Decreasing the Voltage and Increasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 351 Figure 7.25 Transition Diagram for Decreasing the Voltage and Increasing the Current t2 Source VOLD Source VNEW Source Ø V × I 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC 6LQN”,1(: Sink ”IOLD ” IOLD ” INEW VNEW VOLD Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink × I ... 6 7 t1 Page 352 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.4 Sequence Description for Decreasing the Voltage and Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the PS_RDY Message from the Source and tells the Device Policy Manager it is okay to operate at the new power level. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 353 7.3.1.1.1.5 Decreasing the Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage is shown in Figure 7.26, "Transition Diagram for Decreasing the Voltage". The sequence that Shall be followed is described in Table 7.5, "Sequence Description for Decreasing the Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.26, "Transition Diagram for Decreasing the Voltage", the Sink has previously sent a Request Message to the Source. Page 354 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.26 Transition Diagram for Decreasing the Voltage t Source VOLD Source Ø V 3 Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”IOLD VOLD ” IOLD ” IOLD VNEW Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 355 Table 7.5 Sequence Description for Decreasing the Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 356 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.1.1.6 Decreasing the Voltage and the Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while decreasing the voltage and current is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.6, "Sequence Description for Decreasing the Voltage and the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.27, "Transition Diagram for Decreasing the Voltage and the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 357 Figure 7.27 Transition Diagram for Decreasing the Voltage and the Current t1 t2 Source Ø V Ø I 4 Source VOLD Source VNEW Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC Sink ”INEW Sink ”IOLD ” IOLD ” INEW Sink Ø I VNEW VOLD 3 Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Page 358 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.6 Sequence Description for Decreasing the Voltage and the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 359 7.3.1.1.1.7 No change in Current or Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when changing from one (A)PDO to another while the Sink requests the same voltage and Current as it is currently operating at is shown in Figure 7.28, "Transition Diagram for no change in Current or Voltage". The sequence that Shall be followed is described in Table 7.7, "Sequence Description for no change in Current or Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.28, "Transition Diagram for no change in Current or Voltage", the Sink has previously sent a Request Message to the Source. Page 360 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.28 Transition Diagram for no change in Current or Voltage Table 7.7 Sequence Description for no change in Current or Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine waits tSrcTransition then sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine evaluates the PS_RDY Message. Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Sink ”IOLD VBUS doesn’t change Source VOLD Current doesn’t change Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tSrcTransition Good CRC Good CRC tSrcTransReq Vold Source VOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 361 7.3.1.2 Transitions within the same Fixed, Battery or Variable PDO or between Different (A)PDOs 7.3.1.2.1 Increasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current without changing the voltage is shown in Figure 7.29, "Transition Diagram for Increasing the Current". The sequence that Shall be followed is described in Table 7.8, "Sequence Description for Increasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.29, "Transition Diagram for Increasing the Current", the Sink has previously sent a Request Message to the Source. Page 362 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.29 Transition Diagram for Increasing the Current Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Sink ”INEW Source Port Voltage Sink Port Current Sink ”IOLD ” IOLD ” INEW Sink × I VBUS doesn’t change Source × I 3 6 ... 7 § Source VOLD Source VOLD Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tSrcTransition Port to Port Messaging Good CRC tSrcTransReq Good CRC Sink Port Policy Engine t1 t2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 363 Table 7.8 Sequence Description for Increasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t1). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 6 The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. This time duration is indeterminate. 7 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t2) depends on the magnitude of the load change. Page 364 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.2.2 Decreasing the Current Only The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current without changing the voltage is shown in Figure 7.30, "Transition Diagram for Decreasing the Current". The sequence that Shall be followed is described in Table 7.9, "Sequence Description for Decreasing the Current". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.30, "Transition Diagram for Decreasing the Current", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 365 Figure 7.30 Transition Diagram for Decreasing the Current Source VOLD Source VOLD Sink ”IOLD Sink ”INEW VBUS does not change Source Ø I 4 3 ” IOLD ” INEW Sink Ø I Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSTransitionTimer tSrcTransition Good CRC tSrcTransReq Good CRC t1 t2 Page 366 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.9 Sequence Description for Decreasing the Current Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. Policy Engine tells the Device Policy Manager to instruct the power supply to reduce power consumption. 3 The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The Sink Shall be able to operate with lower current within tSnkNewPower (t1); t1 Shall complete before tSrcTransition. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability. The power supply Shall be ready to operate at the new power level within tSrcReady (t2). The power supply informs the Device Policy Manager that it is ready to operate at the new power level. The power supply status is passed to the Policy Engine. 5 The Policy Engine sends the PS_RDY Message to the Sink starting within tSrcTransReq of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 6 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new (A)PDO. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 367 7.3.1.3 Changing Voltage or Current within the same PPS APDO 7.3.1.3.1 Increasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.10, "Sequence Description for Increasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.31, "Transition Diagram for Increasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Page 368 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.31 Transition Diagram for Increasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Port to Port Messaging Source Port Interaction Sink Port Interaction Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Current may change (not to exceed negotiated current) Source CL Current Sink VBUS Current Sink Port Current VOLD Source Port Voltage VNEW Source VBUS Voltage Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 369 Table 7.10 Sequence Description for Increasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to increase its output voltage. The Programmable Power Supply new voltage set- point Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new set-point and whether VBUS is at the corresponding new level, or if the supply is operating in CL mode. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 370 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.2 Decreasing the Programmable Power Supply (PPS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.11, "Sequence Description for Decreasing the Programmable Power Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.32, "Transition Diagram for Decreasing the Programmable Power Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 371 Figure 7.32 Transition Diagram for Decreasing the Programmable Power Supply Voltage Pps Transition Interval Source VOLD Source VNEW Sink draws current continuously (not to exceed negotiated current) VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tPpsSrcTransSmall, tPpsSrcTransLarge Good CRC Good CRC Source Port Current CL doesn’t change Source CL Current Current may change (not to exceed negotiated current) Sink VBUS Current Sink Port Current Page 372 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.11 Sequence Description for Decreasing the Programmable Power Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the Programmable Power Supply starts to decrease its output voltage. The Programmable Power Supply new voltage set- point (corresponding to vPpsNew) Shall be reached by tPpsSrcTransLarge for steps larger than vPpsSmallStep or else by tPpsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall or tPpsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vPpsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 373 7.3.1.3.3 Increasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the current limit in the same APDO, not exceeding the maximum for that APDO and without changing the requested voltage is shown in Figure 7.33, "Transition Diagram for increasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.12, "Sequence Description for increasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.33, "Transition Diagram for increasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. The Sink May draw current equal to the increasing Current Limit of the Source before it has received the PS_RDY Message for the new Request. Page 374 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.33 Transition Diagram for increasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ĺ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 375 Table 7.12 Sequence Description for increasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. 3 The Power Supply increases its Current Limit set- point to the new requested value. The Sink draws current according to the increased Current Limit of the Source. 4 The Policy Engine waits tPpsSrcTransSmall then sends the PS_RDY Message to the Sink starting within tPpsCLProgramSettle of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. 6 Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message and tells the Device Policy Manager it can increase the current up to the requested value without the Source going into CL mode. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink increases its current. Page 376 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.3.4 Decreasing the Programmable Power Supply (PPS) Current The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the current limit in the same APDO, not exceeding the minimum for that APDO and without changing the requested voltage is shown in Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode". The sequence that Shall be followed is described in Table 7.13, "Sequence Description for decreasing the Current in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.34, "Transition Diagram for decreasing the Current in PPS mode", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 377 Figure 7.34 Transition Diagram for decreasing the Current in PPS mode Source IOLD Source INEW 6LQN”,NEW Sink draws current continuously (” old negotiated current) Sink Ĺ | Source Ļ | 3 6 Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current ... 7 Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD PPS Transition Interval Sink Port Current Source CL Current VOLD VNEW CLOLD CLNEW CL change IOLD Follows CL change INEW Passive Sink following CL Source Active Sink at IOLD Set-point V does not change, only resulting V Page 378 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.13 Sequence Description for decreasing the Current in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its set-point for the current limit. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and instructs the Sink to reduce its current to below the new Negotiated current level and starts the PSTransitionTimer. 3 The Power Supply decreases its Current Limit set- point to the new Negotiated value. The Sink reduces its current to less than the new Negotiated current to prevent the Source from going into Current Limit. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. 5 Policy Engine receives the GoodCRC Message from the Sink. Policy Engine receives the PS_RDY Message. 6 Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The Sink is allowed to draw INEW but must be aware the voltage on VBUS can drop doing so. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 379 7.3.1.3.5 Same Request Programmable Power Supply (PPS) The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current is shown in Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode". The sequence that Shall be followed is described in Table 7.14, "Sequence Description for no change in Current or Voltage in PPS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.35, "Transition Diagram for no change in Current or Voltage in PPS mode", the Sink has previ- ously sent a Request Message to the Source. Page 380 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.35 Transition Diagram for no change in Current or Voltage in PPS mode Table 7.14 Sequence Description for no change in Current or Voltage in PPS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then evaluates the Accept Message and starts the PSTransitionTimer. 3 The Policy Engine then sends the PS_RDY Message to the Sink starting within tPpsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY Message. 4 Policy Engine receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer and evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Source IOLD Sink ” IOLD Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Source Port Current Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Port Policy Engine Sink Port Policy Engine Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 Good CRC Good CRC PSTransitionTimer (running) tPpsSrcTransSmall Source VOLD Sink Port Current Source CL Current CL doesn’t change Current doesn’t change VBUS doesn’t change Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 381 7.3.1.4 Changing Voltage or Current within the same AVS APDO 7.3.1.4.1 Increasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when increasing the voltage is shown in Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage". The sequence that Shall be followed is described in Table 7.15, "Sequence Description for Increasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed inTable 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.36, "Transition Diagram for Increasing the Adjustable Power Supply Voltage", the Sink has pre- viously sent a Request Message to the Source. Page 382 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 7.36 Transition Diagram for Increasing the Adjustable Power Supply Voltage AVS Transition Interval Source VOLD Source VNEW Sink draws current continuously for voltage changes less than or equal to vAvsSmallStep. For larger voltage changes, the Sink reduces to iSnkStdby. IOLD VOLD Source × V 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Depends on magnitude of AVS voltage change Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC IOLD Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 383 Table 7.15 Sequence Description for Increasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to increase its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine. Policy Engine then starts the PSTransitionTimer and evaluates the Accept Message. If the voltage increase is larger than vAvsSmallStep, the Sink Shall reduce its current draw to iSnkStdby within tSnkStdby. The reduction to iSnkStdby is not required if the voltage increase is less than or equal to vAvsSmallStep. 3 After sending the Accept Message, the AVS starts to increase its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point. The Sink May begin operating at the new power level any time after evaluation of the PS_RDY Message. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Page 384 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.1.4.2 Decreasing the Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when decreasing the voltage is shown in Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage". The sequence that Shall be followed is described in Table 7.16, "Sequence Description for Decreasing the Adjustable Voltage Supply Voltage". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.37, "Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage", the Sink has previously sent a Request Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 385 Figure 7.37 Transition Diagram for Decreasing the Adjustable Voltage Supply Voltage AVS Transition Interval Source VOLD Source VNEW ”IOLD VOLD Source ØV 3 Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current VNEW Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Sink ”IOLD Page 386 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.16 Sequence Description for Decreasing the Adjustable Voltage Supply Voltage Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to decrease its output voltage. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 After sending the Accept Message, the AVS starts to decrease its output voltage. The AVS new voltage set- point Shall be reached by tAvsSrcTransLarge for steps larger than vAvsSmallStep or else by tAvsSrcTransSmall. The power supply informs the Device Policy Manager that it has reached the new level. The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall or tAvsSrcTransLarge of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 5 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source and tells the Device Policy Manager that the Source is operating at the new voltage set point (corresponding to vAvsNew). If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 387 7.3.1.4.3 Same Request Adjustable Voltage Supply (AVS) Voltage The interaction of the System Policy, Device Policy, and power supply that Shall be followed when the Sink requests the same voltage and current levels as the present Negotiated levels for voltage and current as shown in Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode". The sequence that Shall be followed is described in Table 7.17, "Sequence Description for no change in Current or Voltage in AVS mode". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.38, "Transition Diagram for no change in Current or Voltage in AVS mode", the Sink has previ- ously sent a Request Message to the Source. Figure 7.38 Transition Diagram for no change in Current or Voltage in AVS mode Table 7.17 Sequence Description for no change in Current or Voltage in AVS mode Step Source Port Sink Port 1 Policy Engine sends the Accept Message to the Sink. Policy Engine receives the Accept Message. 2 Protocol Layer receives the GoodCRC Message from the Sink. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then and starts the PSTransitionTimer and evaluates the Accept Message. 3 The Policy Engine sends the PS_RDY Message to the Sink starting within tAvsSrcTransSmall of the end of the GoodCRC Message following the Accept Message. The Policy Engine receives the PS_RDY Message from the Source. 4 Protocol Layer receives the GoodCRC Message from the Sink. Note: The decision that no power transition is re- quired could be made either by the Device Pol- icy Manager or the power supply depending on implementation. Protocol Layer sends the GoodCRC Message to the Source. Policy Engine then stops the PSTransitionTimer, evaluates the PS_RDY Message from the Source. The Sink is already operating at the new power level, so no further action is required. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. Current doesn’t change VBUS doesn’t change Source Port Policy Engine Sink Port Policy Engine Source Port Voltage Sink Port Current Port to Port Messaging Source VBUS Voltage Sink VBUS Current Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 3 4 PSTransitionTimer tAvsSrcTransSmall, tAvsSrcTransLarge Good CRC Good CRC Page 388 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2 Transitions Caused by Power Role Swap 7.3.2.1 Sink Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink requested Power Role Swap is shown in Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.18, "Sequence Description for a Sink Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.39, "Transition Diagram for a Sink Requested Power Role Swap", the Sink has previously sent a PR_Swap Message to the Source. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 389 Figure 7.39 Transition Diagram for a Sink Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 3 4 7 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 5 6 PSSourceOffTimer tSrcTransition Good CRC tSrcTransOff Good CRC PSSourceOnTimer Send PS_RDY Evaluate PS_RDY Good CRC 8 9 tSrcTransOn Page 390 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.18 Sequence Description for a Sink Requested Power Role Swap Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port 1 Policy Engine sends the Accept Message to the Initial Sink. Policy Engine receives the Accept. 2 Protocol Layer receives the GoodCRC Message from the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer sends the GoodCRC Message to the Initial Source. Policy Engine then starts the PSSourceOffTimer and evaluates the Accept Message. 3 Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition min. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). The Sink Shall Not violate transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. 4 tSrcTransition after the GoodCRC Message was received, the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 5 The power supply is ready, and the Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. 6 Protocol Layer receives the GoodCRC Message from the device that will become the New Source. Policy Engine starts the PSSourceOnTimer. Upon sending the PS_RDY Message and receiving the GoodCRC Message the Initial Source is ready to be the New Sink. The Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine the stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before PSTransitionTimer times out the Sink sends Hard Reset Signaling. 7 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 8 Policy Engine receives the PS_RDY Message from the Source. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 391 9 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 10 The power supply as the New Sink transitions from Swap Standby and begins to drawing the current allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.18 Sequence Description for a Sink Requested Power Role Swap (Continued) Step Initial Source Port  New Sink Port Initial Sink Port  New Source Port Page 392 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.2.2 Source Requested Power Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source requested Power Role Swap is shown in Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap". The sequence that Shall be followed is described in Table 7.19, "Sequence Description for a Source Requested Power Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Note: In Figure 7.40, "Transition Diagram for a Source Requested Power Role Swap", the Source has previously sent a PR_Swap Message to the Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 393 Figure 7.40 Transition Diagram for a Source Requested Power Role Swap t4 t2 t3 t1 New Sink New Source New Source New Sink Initial Sink Initial Source Initial Sink Initial Source Source to Swap Standby Sink ” IOLD Swap Standby Swap Standby to Source Swap Standby to Sink Implicit Contract IOLD Source VOLD Sink to Swap Standby VOLD 2a 4 6 not driven Swap Standby vSafe5V 10 not driven I2 I2 I1 I1 Initial Source Port Policy Engine Initial Sink Port Policy Engine Initial Source Port Device Policy Mgr Source Æ Sink Power Supply Initial Sink Port Device Policy Mgr Sink Æ Source Power Supply Source Port Voltage Sink Port Current I1 ” iSnkSwapStdby I2 ”iSnkSwapStdby + cSnkBulkPd( VBUS/ t) Source vSafe5V Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Rd to Rp Ż5p to Rd Send Accept Evaluate Accept Send PS_RDY Evaluate PS_RDY 1 2 4 5 PSSourceOffTimer (running) tSrcTransition Good CRC Good CRC PSSourceOnTimer (running) Send PS_RDY Evaluate PS_RDY Good CRC 7 9 Page 394 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.19 Sequence Description for a Source Requested Power Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port 1 Policy Engine receives the Accept Message. Policy Engine sends the Accept Message to the Initial Source. 2 Protocol Layer sends the GoodCRC Message to the Sink. The Policy Engine tells the Device Policy Manager to instruct the power supply to modify its output power. Protocol Layer receives the GoodCRC Message from the Initial Source. Policy Engine starts the PSSourceOffTimer. 2a The Policy Engine tells the Device Policy Manager to instruct the power supply to transition to Swap Standby. The power supply Shall complete the transition to Swap Standby within tSnkStdby (t1); t1 Shall complete before tSrcTransition. The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. When in Sink Standby the Initial Sink Shall Not draw more than iSnkSwapStdby (I1). 3 tSrcTransition after the GoodCRC Message was sent the power supply starts to change its output power capability to Swap Standby (see Section 7.1.10, "Swap Standby for Sources"). The power supply Shall complete the transition to Swap Standby within tSrcSwapStdby (t2). The power supply informs the Device Policy Manager that it is ready to operate as the New Sink. The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]). The power supply status is passed to the Policy Engine. 4 The Policy Engine sends the PS_RDY Message to the device that will become the New Source, starting within tSrcTransOff of the end of the GoodCRC Message following the Accept Message. Policy Engine receives the PS_RDY. 5 Protocol Layer receives the GoodCRC Message from the soon to be New Source. Policy Engine starts the PSSourceOnTimer. At this point the Initial Source is ready to be the New Sink. Protocol Layer sends the GoodCRC Message to the New Sink. Policy Engine then stops the PSSourceOffTimer and tells the Device Policy Manager to instruct the power supply to operate as the New Source. If the PS_RDY Message is not received before the PSSourceOffTimer times out the Sink starts sending Hard Reset Signaling. 6 The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]). The power supply as the New Source transitions from Swap Standby to sourcing default vSafe5V within tNewSrc (t3). The power supply informs the Device Policy Manager that it is operating as the New Source. 7 Policy Engine receives the PS_RDY Message. Device Policy Manager informs the Policy Engine the power supply is ready, and the Policy Engine sends the PS_RDY Message to the New Sink, starting within tSrcTransOn of the end of the GoodCRC Message following the Accept Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 395 8 Protocol Layer sends the GoodCRC Message to the New Source and then stops the PSSourceOnTimer. Policy Engine evaluates the PS_RDY Message from the New Source and tells the Device Policy Manager to instruct the power supply to draw current as the New Sink. Protocol Layer receives the GoodCRC Message from the New Sink. 9 The power supply as the New Sink transitions from Swap Standby to drawing the power allowed by the Implicit Contract. The power supply informs the Device Policy Manager that it is operating as the New Sink. At this point subsequent Negotiations between the New Source and the New Sink May proceed as normal. The New Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. The time duration (t4) depends on the magnitude of the load change (iLoadStepRate). Table 7.19 Sequence Description for a Source Requested Power Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 396 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3 Transitions Caused by Hard Reset 7.3.3.1 Source Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Source Initiated Hard Reset is shown in Figure 7.41, "Transition Diagram for a Source Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.20, "Sequence Description for a Source Initiated Hard Reset". The timing parameters that Shall be applied are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 397 Figure 7.41 Transition Diagram for a Source Initiated Hard Reset Table 7.20 Sequence Description for a Source Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Sink. Sink receives Hard Reset Signaling. 2 Policy Engine is informed of the Hard Reset. Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine waits tPSHardReset after sending Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 5 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 Source VOLD Send Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 vSafe5V Default current draw § § Source vSafe5V 4 Source vSafe0V Sink ” IOLD Ready to recover and power up Source Recover tSrcRecover 5 Process Hard Reset tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current 2 t2 t1 Page 398 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.3.2 Sink Initiated Hard Reset The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Sink Initiated Hard Reset is shown in Figure 7.42, "Transition Diagram for a Sink Initiated Hard Reset". The sequence that Shall be followed is described in Table 7.21, "Sequence Description for a Sink Initiated Hard Reset". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 399 Figure 7.42 Transition Diagram for a Sink Initiated Hard Reset Table 7.21 Sequence Description for a Sink Initiated Hard Reset Step Source Port Sink Port 1 Policy Engine sends Hard Reset Signaling to the Source. 2 Policy Engine tells the Device Policy Manager to instruct the power supply to prepare for a Hard Reset. 3 The Sink prepares for the Hard Reset within tSnkHardResetPrepare (t1) and passes an indication to the Device Policy Manager. The Sink Shall Not draw more than iSafe0mA when VBUS is driven to vSafe0V. 4 Policy Engine is informed of the Hard Reset. 5 Policy Engine waits tPSHardReset after receiving Hard Reset Signaling and then tells the Device Policy Manager to instruct the power supply to perform a Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). 6 After tSrcRecover the Source applies power to VBUS in an attempt to re-establish communication with the Sink and resume USB Default Operation. The transition to vSafe5V Shall occur within tSrcTurnOn (t3). The Sink Shall Not violate the transient load behavior defined in Section 7.2.6, "Transient Load Behavior" while transitioning to and operating at the new power level. t3 t2 Send Hard Reset Evaluate Hard Reset Sink Prepare VOLD Source Hard Reset 1 ” IOLD iSafe0mA Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Supply Sink Port Device Policy Mgr Sink Port Power Supply Source Port Voltage Sink Port Current vSafe0V 3 4 vSafe5V Defalt current draw § § Source vSafe5V 5 Source vSafe0V Sink ” IOLD Source VOLD Ready to recover and power up Source Recover tSrcRecover 6 tPSHardReset Port to Port Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Process Hard Reset 2 t1 Page 400 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.3.4 Transitions Caused by Fast Role Swap 7.3.4.1 Fast Role Swap The interaction of the System Policy, Device Policy, and power supply that Shall be followed during a Fast Role Swap is shown in Figure 7.43, "Transition Diagram for Fast Role Swap". The parallel sequences that Shall be followed are described in Table 7.22, "Sequence Description for Fast Role Swap". The timing parameters that Shall be followed are listed in Table 7.23, "Source Electrical Parameters", Table 7.24, "Sink Electrical Parameters", and Table 7.25, "Common Source/Sink Electrical Parameters". Negotiations between the New Source and the New Sink May occur after the New Source sends the final PS_RDY Message. Note: In Figure 7.43, "Transition Diagram for Fast Role Swap". and Table 7.22, "Sequence Description for Fast Role Swap" numbers are used to indicate Message related steps and letters are used to indicate other events. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 401 Figure 7.43 Transition Diagram for Fast Role Swap Rp Changed to Rd Signal Fast Swap Detect Fast Swap Old Sink New Sink Old Source A B 2 C Source Port Policy Engine Sink Port Policy Engine Source Port Device Policy Mgr Source Port Power Path Sink Port Device Policy Mgr Sink Port Power Path Source Port Voltage Sink Port Current Port to Port Signaling & Messaging Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Source Stops Send FR_Swap 1 Send Accept Evaluate FR_Swap New Source = vSafe5V Evaluate Accept 3 4 Send PS_RDY Evaluate PS_RDY D1 Sink 5 6 Source VBUS< vSafe5V Send PS_RDY 7 VBUS< vSafe5V Source VBUS Source vSafe5V D2 E Ready & Able to Source vSafe5V Evaluate PS_RDY 8 tFRSwapInit Rd Changed to Rp F G 0 A < tSrcFRSwap discharging Sink 0 V Any voltage > vSafe5V No current may be drawn while VBUS is below vSafe5V Page 402 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 7.22 Sequence Description for Fast Role Swap Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Fast Role Swap Request and Power Transition A The Source connected to the Hub UFP (see Figure 7.16, "VBUS Power during Fast Role Swap") stops sourcing VBUS. B Policy Engine sends the Fast Role Swap Request to the Initial Sink on the CC wire. When VBUS < vSafe5V (min), it tells the Device Policy Manager not to draw more than iSnkStdby until the tSnkFRSwap timer has elapsed. C Policy Engine detects the Fast Role Swap Request on the CC wire from the Initial Source and Shall send the FR_Swap Message back to the Initial Source (that is no longer powering VBUS) within time tFRSwapInit. D1 The Policy Engine monitors for VBUS ≤ vSafe5V so that a PS_RDY Message can be sent to the New Source at Step 5 of the messaging sequence. D2 The Policy Engine monitors for VBUS ≤ vSafe5V so the Initial Sink can assume the Power Role of New Source and begin to source VBUS. E When VBUS = vSafe5V the New Source May provide power to VBUS. When VBUS < vSafe5V the New Source Shall provide power to VBUS within tSrcFRSwap. Once the New Source is providing power, the PS_RDY Message can be sent to the New Sink at Step 7 of the messaging sequence. F The CC termination is changed from Rp to Rd (see [USB Type-C 2.4]) before the New Sink sends the PS_RDY Message at Step 5 to the New Source. G The CC termination is changed from Rd to Rp (see [USB Type-C 2.4]) before the New Source sends the PS_RDY Message at Step 7 to the New Sink. Fast Role Swap Message Sequence 1 Policy Engine receives the FR_Swap Message from the Initial Sink that is transitioning to be the New Source. Policy Engine sends the FR_Swap Message to the Initial Source (that is no longer powering VBUS) after detecting the Fast Role Swap Request at Step C. 2 Protocol Layer sends the GoodCRC Message to the Initial Sink. Policy Engine then evaluates the FR_Swap Message. Protocol Layer receives the GoodCRC Message from the Initial Source. 3 Policy Engine sends an Accept Message to the Initial Sink that is transitioning to be the New Source. Policy Engine receives the Accept Message from the Initial Source that is transitioning to be the New Sink. 4 Protocol Layer receives the GoodCRC Message from the Initial Sink that is transitioning to be the New Source. Protocol Layer sends the GoodCRC Message to the Initial Source that is transitioning to be the New Sink. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 403 5 Policy Engine sends a PS_RDY Message to the Initial Sink that is transitioning to be the New Source. The Policy Engine Shall start the PS_RDY Message at least tFRSwap5V after it has sent the Accept Message, and when Step D1 has also been completed. Policy Engine receives the PS_RDY Message from the New Sink. 6 Protocol Layer receives the GoodCRC Message from the New Source. Protocol Layer sends the GoodCRC Message from the Initial Sink that has completed the transition to New Source. Policy Engine then evaluates the PS_RDY Message. 7 Policy Engine receives the PS_RDY Message from the New Source. Policy Engine sends a PS_RDY Message to the New Sink. The Policy Engine Shall wait for Step E before sending the PS_RDY Message, and Shall send the PS_RDY Message within tFRSwapComplete of receiving the PS_RDY Message from the Initial Source Port. Table 7.22 Sequence Description for Fast Role Swap (Continued) Step Initial Source Port New Sink Port Initial Sink Port  New Source Port Page 404 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 7.4 Electrical Parameters 7.4.1 Source Electrical Parameters The Source Electrical Parameters that Shall be followed are specified in Table 7.23, "Source Electrical Parameters". Table 7.23 Source Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSrcBulk Source bulk capacitance when a Port is powered from a dedicated supply.1 10 µF Section 7.1.2 cSrcBulkShared Source bulk capacitance when a Port is powered from a shared supply.1 120 µF Section 7.1.2 DNL (Differential Non- Linearity) Deviation between ideal analog values corresponding to adjacent input digital values -1 0 +1 LSB Section 7.1.4.2.1 iPpsCLMin SPR PPS Minimum Current Limit setting. 1 A Section 7.1.4.2.2 iPpsCLNew Current Limit accuracy Section 7.1.4.2.2 1A ≤ Operating Current ≤ 3A -150 150 mA Operating current > 3A -5 5 % iPpsCLStep SPR PPS Current Limit programming step size (1 LSB). 50 mA Section 7.1.4.2.2 iPpsCLLoadReleaseRate Maximum load decrease slew rate during Current Limit set-point changes. -150 mA/µs Section 7.1.4.2.2 iPpsCLLoadStepRate Maximum load increase slew rate during Current Limit set-point changes. 150 mA/µs Section 7.1.4.2.2 iPpsCLTransient Allowed output current overshoot when a load increase occurs while in CL mode. New load + 100 mA Section 7.1.4.2.2 Allowed output current undershoot when a load decrease occurs while in CL mode. New load – 100 mA 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 405 iPpsCVCLTransient CV to CL transient current bounds assuming the Operating Voltage reduction of Section 7.2.3.1, "Programmable Power Supply Sink Standby". iPpsCLNe w - 100 New load + 500 mA Section 7.1.4.2.2 tAvsTransient The maximum time for the AVS to be between vAvsNew and vAvsValid in response to a load transient. 5 ms Section 7.1.8.4 tAvsSrcTransLarge The time the AVS set- point Shall transition between requested voltages for steps larger than vAvsSmallStep. 0 700 ms Section 7.1.4.3.1 tAvsSrcTransSmall The time the AVS set- point Shall transition between requested voltages for steps smaller than vAvsSmallStep. 0 50 ms Section 7.1.4.3.1 tNewSnk Time allowed for an Initial Source in Swap Standby to transition New Sink operation. 15 ms Section 7.1.10 Figure 7.39 Figure 7.40 tPpsCLCVTransient CL to CV transient voltage settling time. 275 ms Section 7.1.4.2.2 tPpsCLProgramSettle SPR PPS Current Limit programming settling time. 250 ms Section 7.1.4.2.2 tPpsCLSettle CL load transient current settling time. 250 ms Section 7.1.4.2.2 tPpsCVCLTransient CV to CL transient settling time. 250 ms Section 7.1.8.3 tPpsSrcTransLarge The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps larger than vPpsSmallStep. 0 275 ms Section 7.3.1.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 406 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tPpsSrcTransSmall The time the Programmable Power Supply’s set-point Shall transition between requested voltages for steps less than or equal to vPpsSmallStep. 0 25 ms Section 7.3.1.3 tPpsTransient The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is greater than or equal to 60mA. 5 ms Section 7.1.8.3 The maximum time for the Programmable Power Supply to be between vPpsNew and vPpsValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8.3 tSrcFRSwap Time from the Initial Sink detecting that VBUS has dropped below vSafe5V until the Initial Sink/new Source is able to supply USB Type-C Current (see [USB Type-C 2.4]) 150 µs Section 7.1.13 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 407 tSrcReady SPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies only to SPR Mode voltage transitions. 285 ms Figure 7.2 Figure 7.3 EPR Mode Time from positive/ negative transition start (t0) to when the Source is ready to provide the newly Negotiated power level. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 720 tSrcRecover SPR Mode Time allotted for the Source to recover. 0.66 1.0 s Section 7.1.5 EPR Mode 1.085 1.425 tSrcSettle SPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vSrcNew. Applies only to SPR Mode voltage transitions. 275 ms Figure 7.2 EPR Mode Time from positive/ negative transition start (t0) to when the transitioning voltage is within the range vAvsNew. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 700 tSrcSwapStdby The maximum time for the Source to transition to Swap Standby. 650 ms Section 7.1.10 Figure 7.17 Figure 7.18 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 408 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 tSrcTransient The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is greater or equal to than 60mA. 5 ms Section 7.1.8 The maximum time for the Source output voltage to be between vSrcNew and vSrcValid in response to a load transient when target load is less than 60mA. 150 ms Section 7.1.8 tSrcTransition The time the Source Shall wait before transitioning the power supply to ensure that the Sink has sufficient time to prepare (does not apply to transitions within the same PPS or AVS APDO). 25 35 ms Section 7.3 tSrcTransOff SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the PR_Swap Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 690 ms Section 7.3.2 tSrcTransOn Time from the last bit of the GoodCRC Message acknowledging the PS_RDY Message sent by the new Source, in response to the PR_Swap Message until the PS_RDY Message must be started. 280 ms Section 7.3.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 409 tSrcTransReq SPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies only to SPR Mode voltage transitions. 325 ms Section 7.3 EPR Mode Time from the last bit of the GoodCRC Message acknowledging the Accept Message in response to the Request Message until the PS_RDY Message must be started. Applies to EPR Mode voltage transitions and any voltage transition that either begins or ends in EPR Mode. 760 ms Section 7.3 tSrcTurnOn Transition time from vSafe0V to vSafe5V. 275 ms Figure 7.10 Table 7.20 Table 7.21 vAvsMaxVoltage Maximum Voltage Field in the AVS APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.3.1 vAvsMinVoltage Minimum Voltage Field in the AVS APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.3.1 vAvsNew Adjustable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.4 vAvsSlewNeg AVS maximum slew rate for negative voltage changes. -30 mV/µs Section 7.1.8.4 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 410 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vAvsSlewPos AVS maximum slew rate for positive voltage changes. 30 mV/µs Section 7.1.8.4 vAvsSmallStep AVS step size defined as a small step relative to the previous vAvsNew. -1.0 1.0 V Section 7.1.4.3.1 vAvsStep AVS voltage programming step size. 100 mV Section 7.1.8.4 vAvsValid The range in addition to vAvsNew which the AVS output is considered Valid during and after a transition as well as in response to a transient load condition. -0.5 0.5 V Section 7.1.8.4 vPpsCLCVTransient CL to CV load transient voltage bounds. Operating Voltage * 0.95 – 0.1V Operating Voltage * 1.05 + 0.1V V Section 7.1.4.2.2 vPpsMaxVoltage Maximum Voltage Field in the Programmable Power Supply APDO. APDO Max Voltage *0.95 APDO Max Voltage * 1.05 V Section 7.1.4.2.1 vPpsMinVoltage Minimum Voltage Field in the Programmable Power Supply APDO. APDO Min Voltage *0.95 APDO Min Voltage * 1.05 V Section 7.1.4.2.1 vPpsNew Programmable RDO Output Voltage measured at the Source receptacle. RDO Output Voltage *0.95 RDO Output Voltage RDO Output Voltage *1.05 V Section 7.1.8.3 vPpsShutdown The voltage at which the SPR PPS shuts down when operating in CL. APDO Minimum Voltage * 0.85 APDO Minimum Voltage * 0.95 V Section 7.1.4.2.2 vPpsSlewNeg Programmable Power Supply maximum slew rate for negative voltage changes -30 mV/µs Section 7.1.8.3 vPpsSlewPos Programmable Power Supply maximum slew rate for positive voltage changes 30 mV/µs Section 7.1.8.3 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 411 vPpsSmallStep PPS Step size defined as a small step relative to the previous vPpsNew. -500 500 mV Section 7.1.4.2.2 vPpsStep PPS voltage programming step size (1 LSB). 20 mV Section 7.1.8.3 vPpsValid The range in addition to vPpsNew which the Programmable Power Supply output is considered Valid in response to a load step. -0.1 0.1 V Section 7.1.8.3 vSmallStep VBUS step size increase defined as a small step relative to the previous VBUS when Requesting a different (A)PDO. 500 mV Section 7.1.4.3.1 vSrcNeg Most negative voltage allowed during transition. -0.3 V Figure 7.10 vSrcNew Fixed Supply output measured at the Source receptacle. PDO Voltage *0.95 PDO Voltage PDO Voltage *1.05 V Table 7.2 Variable Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V Battery Supply output measured at the Source receptacle. PDO Minimum Voltage PDO Maximum Voltage V vSrcPeak The range that a Fixed Supply or EPR AVS in Peak Current operation is allowed when overload conditions occur. PDO Voltage *0.90 PDO Voltage *1.05 V Table 6.10 Table 6.16 Figure 7.14 vSrcSlewNeg Maximum slew rate allowed for negative voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. -30 mV/µs Section 7.1.4.2 Table 7.2 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Page 412 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 vSrcSlewPos Maximum slew rate allowed for positive voltage transitions. Limits current based on a 3 A connector rating and maximum Sink bulk capacitance of 100 µF. 30 mV/µs Section 7.1.4 Figure 7.2 vSrcValid The range in addition to vSrcNew which a newly Negotiated voltage is considered Valid during and after a transition as well as in response to a transient load condition. This range also applies to vSafe5V. -0.5 0.5 V Figure 7.2 Figure 7.3 Section 7.1.8 Table 7.23 Source Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) The Source Shall charge and discharge the total bulk capacitance to meet the transition time requirements. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 413 7.4.2 Sink Electrical Parameters The Sink Electrical Parameters that Shall be followed are specified in Table 7.24, "Sink Electrical Parameters". Table 7.24 Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference cSnkBulk Sink bulk capacitance on VBUS at Attach and during FRS after the Initial Source stops sourcing and prior to establishing the First Explicit Contract (see Appendix E, "FRS System Level Example" for an example).1 See [USB 3.2] Section 7.2.2 [USB 3.2] cSnkBulkPd Bulk capacitance on VBUS a Sink is allowed after a successful Negotiation.1 100 µF Section 7.2.2 iLoadReleaseRate Load release di/dt. -150 mA/ µs Section 7.2.6 iLoadStepRate Load step di/dt. 150 mA/ µs Section 7.2.6 iNewFrsSink Maximum current the New Sink can draw during a Fast Role Swap until the New Source applies Rp. Matches the required Fast Role Swap required USB Type-C Current Current field of the Fixed Supply PDO of the Initial Source’s Sink_Capabilities Message. Default USB current or 1.5 or 3.0 A Section 7.1.13 iOvershoot Positive or negative overshoot when a load change occurs less than or equal to iLoadStepRate; relative to the settled value after the load change. -230 230 mA Section 7.2.6 iPpsCLLoadStep Maximum Current set-point change while operating in CL mode. -500 500 mA Section 7.2.3.1 iSafe0mA Maximum current a Sink is allowed to draw when VBUS is driven to vSafe0V. 1.0 mA Figure 7.29 Figure 7.30 iSnkStdby Maximum current during voltage transition. 500 mA Section 7.2.3 iSnkSwapStdby Maximum current a Sink can draw during Swap Standby. Ideally this current is very near to 0 mA largely influenced by Port leakage current. 2.5 mA Section 7.2.7 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Page 414 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 pHubSusp Suspend power consumption for a Hub. 25mW + 25mW per downstream Port for up to 4 ports. 125 mW Section 7.2.3 pSnkSusp Suspend power consumption for a peripheral device. 25 mW Section 7.2.3 tNewSrc Maximum time allowed for an Initial Sink in Swap Standby to transition to New Source operation. 275 ms Section 7.2.7 Table 7.18 Table 7.19 tSnkFRSwap Time during a Fast Role Swap when the New Sink can draw no more than iSnkStdby. 200 µs Section 7.1.13 tSnkHardResetPrepare Time allotted for the Sink power electronics to prepare for a Hard Reset. 15 ms Table 7.12 tSnkNewPower Maximum transition time between power levels. 15 ms Section 7.2.3 tSnkRecover Time for the Sink to resume USB Default Operation. 150 ms Table 7.20 tSnkStdby Time to transition to Sink Standby from Sink. 15 ms Section 7.2.3 tSnkSwapStdby Maximum time for the Sink to transition to Swap Standby. 15 ms Section 7.2.7 vEprMax Highest voltage an EPR Sink is expected to tolerate 55 V Section 7.2.9.2 vSprMax Highest voltage an SPR Sink is expected to tolerate 24 V Section 7.2.9.2 Table 7.24 Sink Electrical Parameters (Continued) Parameter Description MIN TYP MAX UNITS Reference 1) If more bypass capacitance than cSnkBulk max or cSnkBulkPd max is required in the device, then the device Shall incorporate some form of VBUS surge current limiting as described in [USB 3.2] Section 11.4.4.1. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 415 7.4.3 Common Electrical Parameters Electrical Parameters that are common to both the Source and the Sink that Shall be followed are specified in Table 7.25, "Common Source/Sink Electrical Parameters"”. Table 7.25 Common Source/Sink Electrical Parameters Parameter Description MIN TYP MAX UNITS Reference tSafe0V Time to reach vSafe0V max. 650 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tSafe5V Time to reach vSafe5V max. 275 ms Section 7.1.5 Figure 7.10 Table 7.20 Table 7.21 tVCONNReapplied When the UFP is the VCONN Source: time from the last bit of the GoodCRC acknowledging the PS_RDY Message before reapplying VCONN. When the DFP is the VCONN Source: time from when VCONN drops below vRaReconnect. 10 20 ms Figure 7.19 Figure 7.20 tVCONNValid Time from tVCONNReapplied until VCONN is within vVconnValid (see [USB Type-C 2.4]).1 0 5 ms Figure 7.19 Figure 7.20 tVCONNZero Time from the last bit of the GoodCRC acknowledging the Accept Message in response to the Data_Reset Message until VCONN is below vRaReconnect (see [USB Type-C 2.4]). 125 ms Figure 7.19 Figure 7.20 vSafe0V Safe operating voltage at “zero volts”. 0 0.8 V Section 7.1.5 vSafe5V Safe operating voltage at 5V. See [USB 2.0] and [USB 3.2] for allowable VBUS voltage range. 4.75 5.5 V Section 7.1.5 1) tVCONNStable (See [USB Type-C 2.4]) still applies.
8 - Device Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 416)
Page 416 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8 Device Policy 8.1 Overview This section describes the Device Policy and Policy Engine that implements it. For an overview of the architecture and how the Device Policy Manager fits into this architecture, please see Section 2.6, "Architectural Overview". Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 417 8.2 Device Policy Manager The Device Policy Manager is responsible for managing the power used by one or more USB Power Delivery ports. In order to have sufficient knowledge to complete this task it needs relevant information about the device it resides in. Firstly, it has a priori knowledge of the device including the Capabilities of the power supply and the receptacles on each Port since these will for example have specific current ratings. It also has to know information from the USB-C® Port Control module regarding cable insertion, type and rating of cable etc. It also has to have information from the power supply about changes in its Capabilities as well as being able to request power supply changes. With all of this information the Device Policy Manager is able to provide up to date information regarding the Capabilities available to a specific Port and to manage the power resources within the device. When working out the Capabilities for a given Source Port the Device Policy Manager will take into account firstly the current rating of the Port's receptacle and whether the inserted cable is PD or non-PD rated and if so, what is the capability of the plug. This will set an upper bound for the Capabilities which might be offered. After this the Device Policy Manager will consider the available power supply resources since this will bound which voltages and currents might be offered. Finally, the Device Policy Manager will consider what power is currently allocated to other ports, which power is in the Power Reserve and any other amendments to Policy from the System Policy Manager. The Device Policy Manager will offer a set of Capabilities within the bounds detailed above. When selecting a capability for a given Sink Port the Device Policy Manager will look at the Capabilities offered by the Source. This will set an upper bound for the Capabilities which might be requested. The Device Policy Manager will also consider which Capabilities are required by the Sink in order to operate. If an appropriate match for voltage and Current can be found within the limits of the receptacle and cable, then this will be requested from the Source. If an appropriate match cannot be found then a request for an offered voltage and current will be made, along with an indication of a Capabilities Mismatch. USB PD defines two types of power sources:  Predefined voltage sources (Fixed Supply, Variable Supply and Battery Supply)  Programmable voltage sources:  Programmable Power Supply (PPS)  Adjustable Voltage Supply (AVS) The first are generally used for classic charging wherein the Charger electronics reside inside the Sink. The Device Policy Manager in the Sink requests a fixed voltage from the list of PDOs offered by the Source and which is converted internally to charge the Sink's Battery and/or power its function. The second moves the Charger electronics that manage the voltage control outside the Sink and back into the Source itself. When in SPR PPS Mode, the Device Policy Manager in the Sink requests a specific voltage with a 20mV accuracy and sets a current limit. Unlike traditional USB where Sinks are responsible for limiting the current, they consume, the SPR PPS Source limits the current to what the Sink has requested. When operating in, the Device Policy Manager in the Sink requests a specific voltage with a 100mV accuracy and requests a maximum current it is allowed to draw. Note: The AVS Sources unlike SPR PPS Sources do not support current limit mode. A Sink operating in is respon- sible not to draw more current than it requests. The process to request power is the same for both types of power Sources although the actual format and contents of the request are slightly different. The primary operational differences are:  A Sink that is using SPR PPS is required to periodically sent requests to let the Source know it is still alive and communicating. When this communication fails a Hard Reset results.  A Sink operating in SPR Mode has no special timing requirements.  A Sink operating in EPR Mode is required to periodically communicate with the Source to let it know it is still operational. If the communication fails, a Hard Reset results. For Dual-Role Power Ports the Device Policy Manager manages the functionality of both a Source and a Sink. In addition, it is able to manage the Power Role Swap process between the two. In terms of power management this Page 418 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 could mean that a Port which is initially consuming power as a Sink is able to become a power resource as a Source. Conversely, Attached Sources might request that power be provided to them. The functionality within the Device Policy Manager (and to a certain extent the Policy Engine) is scalable depending on the complexity of the device, including the number of different power supply Capabilities and the number of different features supported for example System Policy Manager interface or Capabilities Mismatch, and the number of ports being managed. Within these parameters it is possible to implement devices from very simple power supplies to more complex power supplies or devices such as USB Hubs or Hard Drives. Within multi-Port devices it is also permitted to have a combination of USB Power Delivery and non-USB Power Delivery ports which Should all be managed by the Device Policy Manager. As noted in Section 2.6, "Architectural Overview" the logical architecture used in the PD specification will vary depending on the implementation. This means that different implementations of the Device Policy Manager might be relatively small or large depending on the complexity of the device, as indicated above. It is also possible to allocate different responsibilities between the Policy Engine and the Device Policy Manager, which will lead to different types of architectures and interfaces. The Device Policy Manager is responsible for the following:  Maintaining the Local Policy for the device.  For a Source, monitoring the present Capabilities and triggering notifications of the change.  For a Sink, evaluating and responding to Capabilities related requests from the Policy Engine for a given Port.  Control of the Source/Sink in the device.  Control of the USB-C® Port Control module for each Port.  Interface to the Policy Engine for a given Port. The Device Policy Manager is responsible for the following Optional features when implemented:  Communications with the System Policy over USB.  For Sources with multiple ports monitoring and balancing power requirements across these ports.  Monitoring of batteries and AC power supplies.  Managing Modes in its Port Partner and Cable Plug(s). 8.2.1 Capabilities The Device Policy Manager in a Provider Shall know the power supplies available in the device and their Capabilities. In addition, it Shall be aware of any other PD sources of power such as batteries and AC inputs. The available power sources and existing demands on the device Shall be taken into account when presenting Capabilities to a Sink. The Device Policy Manager in a Consumer Shall know the requirements of the Sink and use this to evaluate the Capabilities offered by a Source. It Shall be aware of its own power sources e.g., Batteries or AC supplies where these have a bearing on its operation as a Sink. The Device Policy Manager in a Dual-Role Power Device Shall combine the above Capabilities and Shall also be able to present the dual-role nature of the device to an Attached PD Capable device. 8.2.2 System Policy A given PD Capable device might have no USB capability, or PD might have been added to a USB device in such a way that PD is not integrated with USB. In these two cases there Shall be no requirement for the Device Policy Manager to interact with the USB interface of the device. The following requirements Shall only apply to PD devices that expose PD functionality over USB. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 419 The Device Policy Manager Shall communicate over USB with the System Policy Manager according to the requirements detailed in [UCSI]. Whenever requested the Device Policy Manager Shall implement a Local Policy according to that requested by the System Policy Manager. For example, the System Policy Manager might request that a Battery powered Device temporarily stops charging so that there is sufficient power for an HDD to spin up. Note: Due to timing constraints, a PD Capable device Shall be able to respond autonomously to all time-critical PD related requests. 8.2.3 Control of Source/Sink The Device Policy Manager for a Provider Shall manage the power supply for each PD Source Port and Shall know at any given time what the Negotiated power is. It Shall request transitions of the supply and inform the Policy Engine whenever a transition completes. The Device Policy Manager for a Consumer Shall manage the Sink for each PD Sink Port and Shall know at any given time what the Negotiated power is. The Device Policy Manager for a Dual-Role Power Device Shall manage the transition between Source/Sink Power Roles for each PD Dual-Role Power Port and Shall know at any given time what Power Role the Port is in. 8.2.4 Cable Detection 8.2.4.1 Device Policy Manager in a Provider The Device Policy Manager in the Provider Shall control the USB-C® Port Control module and Shall be able to use the USB-C® Port Control module to determine the Attachment status. Note: It might be necessary for the Device Policy Manager to also initiate additional discovery using the Discov- er Identity Command in order to determine the full Capabilities of the cabling (see Section 6.4.4.3.1, "Dis- cover Identity"). 8.2.4.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer controls the USB-C® Port Control module and Shall be able to use the USB- C® Port Control module to determine the Attachment status. 8.2.4.3 Device Policy Manager in a Consumer/Provider The Device Policy Manager in a Consumer/Provider inherits characteristics of Consumers and Providers and Shall control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Attachment of a USB Power Delivery Provider/Consumer which supports Dead Battery back-powering.  Presence of VBUS. 8.2.4.4 Device Policy Manager in a Provider/Consumer The Device Policy Manager in a Provider/Consumer inherits characteristics of Consumers and Providers and May control the USB-C® Port Control module in order to support the Dead Battery back-powering case to determine the following for a given Port:  Presence of VBUS. Page 420 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.2.5 Managing Power Requirements It is the responsibility of the Device Policy Manager in a Provider to be aware of the power requirements of all devices connected to its Source Ports. This includes being aware of any reserve power that might be required by devices in the future and ensuring that power is shared optimally amongst Attached PD Capable devices. This is a key function of the Device Policy Manager; whose implementation is critical to ensuring that all PD Capable devices get the power they require in a timely fashion in order to facilitate smooth operation. This is balanced by the fact that the Device Policy Manager is responsible for managing the sources of power that are, by definition, finite. The Consumer's Device Policy Manager Shall ensure that it takes no more power than is required to perform its functions and when its requirements change, it Should make a new Request. The Provider, after satisfying the Request, Should reclaim any unused power to ensure that it can meet total power requirements of Attached Sinks on at least one Port. Note: It is expected that a future design guide will provide additional guidance. 8.2.5.1 Managing the Power Reserve There might be some products where a Device has certain functionality at one power level and a greater functionality at another, for example a Printer/Scanner that operates only as a printer with one power level and as a scanner if it can get more power. While the visibility of the linkage between power and functionality might only be apparent to the USB Host; the Device Policy Manager Should provide mechanisms to manage the power requirements of such Devices. It is the Device Policy Manager's responsibility to allocate power and maintain a power reserve so as not to over- subscribe its available power resource. A Device with multiple ports such as a Hub Shall always attempt to meet the incremental demands of the Port requiring the highest incremental power from its power reserve. 8.2.5.2 Power Capability Mismatch A Capabilities Mismatch occurs when a Consumer cannot obtain required power from a Provider (or the Source is not PD Capable) and the Consumer requires such Capabilities to operate. Different actions are taken by the Device Policy Manager and the System Policy Manager in this case. 8.2.5.2.1 Local device handling of mismatch The Consumer's Device Policy Manager Shall cause a notification to be displayed to the end user that a power Capabilities Mismatch has occurred. Examples of such feedback can include:  For a simple Device an LED May be used to indicate the failure. For example, during connection the LED could be solid amber. If the connection is successful, the LED could change to green. If the connection fails, it could be red or alternately blink amber.  A more sophisticated Device with a user interface, e.g., a mobile device or monitor, Should provide no- tification through the user interface on the Device. The Provider's Device Policy Manager May cause a notification to be displayed to the user of the power Capabilities Mismatch. Because the Capabilities Mismatch might not cause operational failure, the Provider's Device Policy Manager Should Not display a notification to the user if the power offered to the Sink meets or exceeds the SPR Sink Minimum PDP/ EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message (see Section 6.5.13, "Sink_Capabilities_Extended Message"). If a notification is displayed, it Should Not be shown as an error unless the power offered to the Sink is less than the SPR Sink Minimum PDP/EPR Sink Minimum PDP Advertised in the Sink_Capabilities_Extended Message. 8.2.5.2.2 Device Policy Manager Communication with System Policy In a USB Power Delivery aware system with an active System Policy Manager (see Section 8.2.2, "System Policy"), the Device Policy Manager Shall notify the System Policy Manager of the mismatch. This information Shall be passed back to the System Policy Manager using the mechanisms described in [UCSI]. The System Policy Manager Should Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 421 ensure that the user is informed of the condition. When another Port in the system could satisfy the Consumer's power requirements the user Should be directed to move the Device to the alternate Port. In order to identify a more suitable Source Port for the Consumer the System Policy Manager Shall communicate with the Device Policy Manager in order to determine the Consumer's requirements. The Device Policy Manager Shall use a Get_Sink_Cap Message (see Section 6.3.8, "Get_Sink_Cap Message") to discover which power levels can be utilized by the Consumer. 8.2.6 Use of "Unconstrained Power" bit with Batteries and AC supplies The Device Policy Manager in a Provider or Consumer May monitor the status of any variable sources of power that could have an impact on its Capabilities as a Source such as Batteries and AC supplies and reflect this in the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") provided as part of the Source_Capabilities or Sink_Capabilities Message (see Section 6.4.1, "Capabilities Message"). When monitored, and a USB interface is supported, the External Power status (see [UCSI]) and the Battery state (see Section 9.4.1, "GetBatteryStatus") Shall also be reported to the System Policy Manager using the USB interface. 8.2.6.1 AC Supplies The Unconstrained Power bit provided by Sources and Sinks (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power") notifies a connected device that it is acceptable to use the Advertised power for charging as well as for what is needed for normal operation. A device that sets the Unconstrained Power bit has either an external source of power that is sufficient to adequately power the system while charging external devices or expects to charge external devices as a primary state of function (such as a battery pack). In the case of the external power source, the power can either be from an AC Supply directly connected to the device or from an AC Supply connected to an Attached device, which is also getting unconstrained power from its power supply. The Unconstrained Power bit is in this way communicated through a PD system indicating that the origin of the power is from a single or multiple AC supplies, from a battery bank, or similar:  If the "Unconstrained Power" bit is set, then that power is originally sourced from an AC Supply.  Devices capable of consuming on multiple ports can only claim that they have "Unconstrained Power" for the power Advertised as a Provider Port if there is unconstrained power beyond that needed for nor- mal operation coming from external supplies, (e.g., multiple AC supplies).  This concept applies as the power is routed through multiple Provider and Consumer tiers, so, as an ex- ample. Power provided out of a monitor that is connected to a monitor that gets power from an AC Sup- ply, will claim it has "Unconstrained Power" even though it is not directly connected to the AC Supply. An example use case is a Tablet computer that is used with two USB A/V displays that are daisy chained (see Figure 8.1, "Example of daisy chained displays"). The tablet and 1st display are not externally powered, (meaning, they have no source of power outside of USB PD). The 2nd display has an external supply Attached which could either be a USB PD based supply or some other form of external supply. When the displays are connected as shown, the power adapter Attached to the 2nd display is able to power both the 1st display and the tablet. In this case the 2nd display will indicate the presence of a sufficiently sized Charger to the 1st display, by setting its "Unconstrained Power" bit. The 1st display will then in turn assess and indicate the presence of the extra power to the tablet by setting its "Unconstrained Power" bit. Power is transmitted through the system to all devices, provided that there is sufficient power available from the external supply. Page 422 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.1 Example of daisy chained displays Another example use case is a laptop computer that is Attached to both an external supply and a Tablet computer. In this situation, if the external supply is large enough to power the laptop in its normal state as well as charge an external device, the laptop would set its "Unconstrained Power" bit and the tablet will allow itself to charge at its peak rate. If the external supply is small, however, and would not prevent the laptop from discharging if maximal power is drawn by the external device, the laptop would not set its "Unconstrained Power" bit, and the tablet can choose to draw less than what is offered. This amount could be just enough to prevent the tablet from discharging, or none at all. Alternatively, if the tablet determines that the laptop has significantly larger battery with more charge than the tablet has, the tablet can still choose to charge itself, although possibly not at the maximal rate. In this way, Sinks that do not receive the Unconstrained Power bit from the connected Source can still choose to charge their batteries, or charge at a reduced rate, if their policy determines that the impact to the Source is minimal -- such as in the case of a phone with a small battery charging from a laptop with a large battery. These policies can be decided via further USB PD communication. 8.2.6.2 Battery Supplies When monitored, and a USB interface is supported, the Battery state Shall be reported to the System Policy Manager using the USB interface. If the device is Battery-powered but is in a state that is primarily for charging external devices, the device is considered to be an unconstrained source of power and thus Should set the "Unconstrained Power" bit. A simplified algorithm is detailed below to ensure that Battery powered devices will get charge from non-Battery powered devices when possible, and also to ensure that devices do not constantly Power Role Swap back and forth. When two devices are connected that do not have Unconstrained Power, they Should define their own policies so as to prevent constant Power Role Swapping. This algorithm uses the "Unconstrained Power" bit (see Section 6.4.1.2.1.3, "Unconstrained Power" and Section 6.4.1.3.1.3, "Unconstrained Power"), thus the decisions are based on the availability and sufficiency of an external supply, not the full Capabilities of a system or device or product. Recommendations:  Provider/Consumers using large external sources ("Unconstrained Power" bit set) Should always deny Power Role Swap requests from Consumer/Providers not using external sources ("Unconstrained Pow- er" bit cleared). AC Tablet Display 1 Display 2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 423  Provider/Consumers not using large external sources ("Unconstrained Powered" bit cleared) Should al- ways accept a Power Role Swap request from a Consumer/Provider using large external power sources ("Unconstrained Power" bit set) unless the requester is not able to provide the requirements of the present Provider/Consumer. 8.2.7 Interface to the Policy Engine The Device Policy Manager Shall maintain an interface to the Policy Engine for each Port in the device. 8.2.7.1 Device Policy Manager in a Provider The Device Policy Manager in a Provider Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/ device Attachment status for a given cable.  Inform the Policy Engine whenever the Source Capabilities available for a Port change.  Evaluate requests from an Attached Consumer and provide responses to the Policy Engine.  Respond to requests for power supply transitions from the Policy Engine.  Indication to Policy Engine when power supply transitions are complete.  Maintain a power reserve for devices operating on a Port at less than maximum power. 8.2.7.2 Device Policy Manager in a Consumer The Device Policy Manager in a Consumer Shall also provide the following functions to the Policy Engine:  Inform the Policy Engine of changes in cable/device Attachment status.  Inform the Policy Engine whenever the power requirements for a Port change.  Evaluate Source Capabilities and provide suitable responses:  Request from offered Capabilities.  Indicate whether additional power is required.  Respond to requests for Sink transitions from the Policy Engine. 8.2.7.3 Device Policy Manager in a Dual-Role Power Device The Device Policy Manager in a Dual-Role Power Device Shall provide the following functions to the Policy Engine:  Provider Device Policy Manager  Consumer Device Policy Manager  Interface for the Policy Engine to request power supply transitions from Source to Sink and vice versa.  Indications to Policy Engine during Power Role Swap transitions. 8.2.7.4 Device Policy Manager in a Dual-Role Power Device Dead Bat- tery handling The Device Policy Manager in a Dual-Role Power Device with a Dead Battery Should:  Switch Ports to Sink-only or Sink DFP operation to obtain power from the next Attached Source.  Use VBUS from the Attached Source to power the USB Power Delivery communications as well as charging to enable the Negotiation of higher input power. Page 424 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3 Policy Engine 8.3.1 Introduction There is one Policy Engine instance per Port that interacts with the Device Policy Manager in order to implement the present Local Policy for that particular Port. This section includes:  AMSs for various operations.  State diagrams covering operation of Sources, Sinks and Cable Plugs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 425 8.3.2 Atomic Message Sequence Diagrams 8.3.2.1 Introduction The Policy Engine drives the Atomic Message Sequences (AMS) and responses based on both the expected AMSs and the present Local Policy. An AMS Shall be defined as a Message sequence that starts and/or ends in either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states (see Section 8.3.3.2, "Policy Engine Source Port State Diagram", Section 8.3.3.3, "Policy Engine Sink Port State Diagram" and Section 8.3.3.25, "Cable Plug Specific State Diagrams"). In addition, the Cable Plug discovery sequence specified in Section 8.3.3.25.3, "Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram" Shall be defined as an AMS. The Source and Sink indicate to the Protocol Layer when an AMS starts and ends on entry to/exit from PE_SRC_Ready or PE_SNK_Ready (see Section 8.3.3.2, "Policy Engine Source Port State Diagram" and Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). An AMS Shall be considered to have been started by the Initiator when the protocol engine signals the Policy Engine that transmission is a success (the GoodCRC Message has been received in response to the initial Message). For the receiving Port the AMS Shall be considered to have started when the initial Message has arrived. An AMS Shall be considered to have ended:  When the Protocol Layer signals the Policy Engine that transmission of the final Message in the AMS is a success and for the opposite Port when the final Message has been received.  A Soft_Reset Message, Hard Reset Signaling for SOP’ or SOP’’ or Cable Reset Signaling has been sent or received. Section 8.3.2.1.3, "Atomic Message Sequences" gives details of these AMS's. This section contains sequence diagrams that highlight some of the more interesting transactions. It is by no means a complete summary of all possible combinations but is Informative in nature. Page 426 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.1 Basic Message Exchange Figure 8.2, "Basic Message Exchange (Successful)" below illustrates how a Message is sent. Table 8.1, "Basic Message Flow" details the steps in the flow. Note that the sender might be either a Source or Sink while the receiver might be either a Sink or Source. The basic Message sequence is the same. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. Figure 8.2 Basic Message Exchange (Successful) Table 8.1 Basic Message Flow Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 7 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Protocol Layer checks and increments the MessageIDCounter and stops CRCReceiveTimer. 9 Protocol Layer informs the Policy Engine that the Message was successfully sent. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 427 8.3.2.1.2 Errors in Basic Message flow There are various points during the Message flow where failures in communication or other issues can occur. Figure 8.3, "Basic Message flow indicating possible errors" is an annotated version of Figure 8.2, "Basic Message Exchange (Successful)" indicating at which point issues can occur. Table 8.2, "Potential issues in Basic Message Flow" details the steps in the flow. Figure 8.3 Basic Message flow indicating possible errors Table 8.2 Potential issues in Basic Message Flow Point Possible issues A 1) There is an incoming Message on the channel meaning that the PHY Layer is unable to send. In this case the outgoing Message is removed from the queue and the incoming Message processed. 2) Due to some sort of noise on the line it is not possible to transmit. In this case the outgoing Message is Discarded by the PHY Layer. Retransmission is via the Protocol Layer’s normal mechanism. B 1) Message does not arrive at the PHY Layer due to noise on the channel. 2) Message arrives but has been corrupted and has a bad CRC. There is no Message to pass up to the Protocol Layer on the receiver which means a GoodCRC Message is not sent. This leads to a CRCReceiveTimer timeout in the Message Sender. C 1) MessageID of received Message matches stored MessageID so this is a retry. Message is not passed up to the Policy Engine. D 1) Policy Engine receives a known Message that it was not expecting. 2) Policy Engine receives an Unrecognized Message. These cases are errors in the protocol which could lead to the generation of a Soft_Reset Message. E Same as point A but at the Message Receiver side. : Policy Engine : Protocol 1: Send message : PHY : PHY : Protocol : Policy Engine 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Message received Consume message 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Message sent Message Sender Message Receiver • Message currently being received • Channel unavailable • Message does not arrive • Message has bad CRC • Message is a retry • Message is unexpected • Message is unknown • Message currently being received • Channel unavailable • GoodCRC does not arrive • GoodCRC has a bad CRC • GoodCRC has the wrong MessageID • Response is not GoodCRC A B C D E F G Page 428 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.4, "Basic Message Flow with Bad followed by a Retry" illustrates one of these cases; the basic Message flow with a retry due to a bad CRC at the Message Receiver. It starts when the Message Sender's Protocol Layer at the behest of its Policy Engine forms a Message that it passes to the PHY Layer. The Protocol Layer is responsible for retries on a “'n' strikes and you are out" basis (nRetryCount). Table 8.3, "Basic Message Flow with CRC failure" details the steps in the flow. Figure 8.4 Basic Message Flow with Bad followed by a Retry F 1) GoodCRC Message response does not arrive at the Message Sender side due to the noise on the channel. 2) GoodCRC Message response arrives but has a bad CRC. A GoodCRC Message is not received by the Message Sender’s Protocol Layer. This leads to a CRCReceiveTimer timeout in the Message Sender. G 1) GoodCRC Message is received but does contain the same MessageID as the transmitted Message. 2) A Message is received but it is not a GoodCRC Message (similar case to that of an unexpected or unknown Message but this time detected in the Protocol Layer). Both of these issues indicate errors in receiving an expected GoodCRC Message which will lead to a CRCReceiveTimer timeout in the Protocol Layer and a subsequent retry (except for communications with Cable Plugs). Table 8.2 Potential issues in Basic Message Flow Point Possible issues : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine 4: Message 5: Message + CRC 6: Message Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 7: Message received Consume message 8: GoodCRC 9: GoodCRC + CRC 10: GoodCRC Check and increment MessageIDCounter Reset RetryCounter Stop CRCReceiveTimer 11: Message sent 1: Send message 2: Message 3: Message + CRC Start CRCReceiveTimer CRCReceiveTimer expires Retry and increment RetryCounter Message is not received or CRC is bad so message is not passed to the protocol layer Message Sender Message Receiver Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 429 Table 8.3 Basic Message Flow with CRC failure Step Message Sender Message Receiver 1 Policy Engine directs Protocol Layer to send a Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives no Message or a Message with an incorrect CRC. Nothing is passed to Protocol Layer. 4 Since no response is received, the CRCReceiveTimer will expire and trigger the first retry by the Protocol Layer. The RetryCounter is incremented. Protocol Layer passes the Message to the PHY Layer. 5 PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and checks the CRC to verify the Message. 6 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 7 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 8 Protocol Layer generates a GoodCRC Message and passes it to the PHY Layer. 9 PHY Layer receives the Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 10 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 11 Protocol Layer verifies the MessageID, stops CRCReceiveTimer and resets the RetryCounter. Protocol Layer informs the Policy Engine that the Message was successfully sent. Page 430 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3 Atomic Message Sequences The types of Atomic Message Sequences (AMS) are listed in Table 8.4, "Atomic Message Sequences". The following tables list sequences of either Messages or combinations of Messages and one or more embedded AMSes which are Non-interruptible. Where there is an embedded AMS the entire Message sequence is treated as an AMS and the Rp value used for Collision Avoidance (see Section 5.7, "Collision Avoidance") Shall only be changed on leaving or entering the ready state at the beginning or end of the entire Message sequence, and not at the start or end of the embedded AMS. Note: An AMS is has not started until the first Message in the sequence has been successfully sent (i.e., a GoodCRC Message has been received acknowledging the Message). Table 8.31, "AMS: Hard Reset" details a Hard Reset (which is Signaling not an AMS) followed by an SPR Contract Negotiation AMS which Shall be treated as Non-interruptible. Table 8.4 Atomic Message Sequences Type of AMS Table Reference Section Reference Power Negotiation (SPR) Table 8.5, "AMS: Power Negotiation (SPR)" Section 8.3.2.2.1 Power Negotiation (EPR) Table 8.6, "AMS: Power Negotiation (EPR)" Section 8.3.2.2.2 Unsupported Message Table 8.7, "AMS: Unsupported Message" Section 8.3.2.3 Soft Reset Table 8.8, "AMS: Soft Reset" Section 8.3.2.4 Data Reset Table 8.9, "AMS: Data Reset" Section 8.3.2.5 Hard Reset Table 8.31, "AMS: Hard Reset" Section 8.3.2.6 Power Role Swap Table 8.10, "AMS: Power Role Swap" Section 8.3.2.7 Fast Role Swap Table 8.11, "AMS: Fast Role Swap" Section 8.3.2.8 Data Role Swap Table 8.12, "AMS: Data Role Swap" Section 8.3.2.9 VCONN Swap Table 8.13, "AMS: VCONN Swap" Section 8.3.2.10 Alert Table 8.14, "AMS: Alert" Section 8.3.2.11.1 Status Table 8.15, "AMS: Status" Section 8.3.2.11.2 Source Capabilities/ Sink Capabilities (SPR) Table 8.16, "AMS: Source/Sink Capabilities (SPR)" Section 8.3.2.11.3.1 Source Capabilities/ Sink Capabilities (EPR) Table 8.17, "AMS: Source/Sink Capabilities (EPR)" Section 8.3.2.11.3.2 Extended Capabilities Table 8.18, "AMS: Extended Capabilities" Section 8.3.2.11.4 Battery Capabilities and Status Table 8.19, "AMS: Battery Capabilities" Section 8.3.2.11.5 Manufacturer Information Table 8.20, "AMS: Manufacturer Information" Section 8.3.2.11.6 Country Codes Table 8.21, "AMS: Country Codes" Section 8.3.2.11.7 Country Information Table 8.22, "AMS: Country Information" Section 8.3.2.11.8 Revision Information Table 8.23, "AMS: Revision Information" Section 8.3.2.11.9 Source Information Table 8.24, "AMS: Source Information" Section 8.3.2.11.10 Security Table 8.25, "AMS: Security" Section 8.3.2.12 Firmware Update Table 8.26, "AMS: Firmware Update" Section 8.3.2.13 Structured VDM Table 8.27, "AMS: Structured VDM" Section 8.3.2.14 Built-In Self-Test (BIST) Table 8.28, "AMS: Built-In Self-Test (BIST)" Section 8.3.2.15 Enter USB Table 8.29, "AMS: Enter USB" Section 8.3.2.16 Unstructured VDM Table 8.30, "AMS: Unstructured VDM" Section 8.3.2.17 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 431 8.3.2.1.3.1 AMS: Power Negotiation (SPR) Table 8.5 AMS: Power Negotiation (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref SPR Explicit Contract Negotiation (Accept) 1. Source_Capabilities Message 2. Request Message 3. Accept Message 4. PS_RDY Message Started by Source, SPR Mode Section 8.3.2.2.1.1.1 Section 8.3.3.2, Section 8.3.3.3 SPR Explicit Contract Negotiation (Reject) 1. Source_Capabilities Message 2. Request Message 3. Reject Message Section 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Wait) 1. Source_Capabilities Message 2. Request Message 3. Wait Message Section 8.3.2.2.1.1.3 SPR PPS Keep Alive 1. Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, SPR Mode Section 8.3.2.2.1.2 Section 8.3.3.3 SPR Sink Makes Request (Accept) 1. Request Message 2. Accept Message 3. PS_RDY Message Section 8.3.2.2.1.3.1 Section 8.3.3.2, Section 8.3.3.3 SPR Sink Makes Request (Reject) 1. Request Message 2. Reject Message Section 8.3.2.2.1.3.2 SPR Sink Makes Request (Wait) 1. Request Message 2. Wait Message Section 8.3.2.2.1.3.3 Page 432 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.2 AMS: Power Negotiation (EPR) Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Entering EPR Mode (Success) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS (Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Succeeded) Message 6. EPR Explicit Contract Negotiation AMS Started by Sink, SPR Mode Section 8.3.2.2.2.1, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3, Section 8.3.2.2.2.4 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1, Section 8.3.3.2, Section 8.3.3.3 Entering EPR Mode (Failure due to non-EPR Cable) 1. EPR_Mode (Enter) Message 2. EPR_Mode (Enter Acknowledge) Message 3. VCONN Source Swap, initiated by non- VCONN Source (Accept) AMS(Optional). 4. Initiator to Responder Discover Identity (ACK) AMS (Optional for Sources with captive cables) 5. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.2, Section 8.3.2.10.1, Section 8.3.2.10.2, Section 8.3.2.12.3 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19, Section 8.3.3.20.1, Section 8.3.3.21.1 Entering EPR Mode (Failure of VCONN Swap) 1. EPR_Mode (Enter) Message. 2. EPR_Mode (Enter Acknowledge) Message. 3. VCONN Source Swap, initiated by non- VCONN Source (Reject) AMS(Optional). 4. EPR_Mode (Enter Failed) Message Started by Sink, SPR Mode Section 8.3.2.2.2.3, Section 8.3.2.10.1, Section 8.3.2.10.2 Section 8.3.3.25.1, Section 8.3.3.25.2, Section 8.3.3.19 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 433 EPR Explicit Contract Negotiation (Accept) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Accept Message 4. PS_RDY Message Started by Source, EPR Mode Section 8.3.2.2.2.2.1 Section 8.3.3.2, Section 8.3.3.3 EPR Explicit Contract Negotiation (Reject) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Reject Message Section 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Wait) 1. EPR_Source_Capabilities Message 2. EPR_Request Message 3. Wait Message Section 8.3.2.2.2.2.3 EPR Keep Alive 1. EPR_KeepAlive Message 2. EPR_KeepAlive_Ack Message Started by Sink, EPR Mode Section 8.3.2.2.2.3 Exiting EPR Mode (Sink Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Sink, EPR Mode Section 8.3.2.2.2.4.1, Section 8.3.2.2.1.1 Section 8.3.3.25.3, Section 8.3.3.25.4, Section 8.3.3.2, Section 8.3.3.3 Exiting EPR Mode (Source Initiated) 1. EPR_Mode (Exit) Message 2. SPR Explicit Contract Negotiation AMS Started by Source, EPR Mode Section 8.3.2.2.2.4.2, Section 8.3.2.2.1.1 EPR Sink Makes Request (Accept) 1. EPR_Request Message 2. Accept Message 3. PS_RDY Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.1 Section 8.3.3.2, Section 8.3.3.3 EPR Sink Makes Request (Reject) 1. EPR_Request Message 2. Reject Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.2 EPR Sink Makes Request (Wait) 1. EPR_Request Message 2. Wait Message Started by Sink, EPR Mode Section 8.3.2.2.2.5.3 Table 8.6 AMS: Power Negotiation (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Page 434 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.3 AMS: Unsupported Message 8.3.2.1.3.4 AMS: Soft Reset 8.3.2.1.3.5 AMS: Data Reset Table 8.7 AMS: Unsupported Message AMS Message Sequence Conditions AMS Ref State Machine Ref Unsupported Message 1. Any Message which is not supported by the Source or Sink 2. Not_Supported Message Started by Source or Sink Section 8.3.2.3 Section 8.3.3.6.2 Table 8.8 AMS: Soft Reset AMS Message Sequence Conditions AMS Ref State Machine Ref Soft Reset 1. Soft_Reset Message 2. Accept Message 3. In SPR Mode: SPR Explicit Contract Negotiation AMS 4. or in EPR Mode: EPR Explicit Contract Negotiation AMS. Started by Source or Sink Section 8.3.2.4, Section 8.3.2.2.1.1, Section 8.3.2.2.1.1, Section 8.3.2.2.2.2 Section 8.3.3.4.1, Section 8.3.3.4.2, Section 8.3.3.25.2.1, Section 8.3.3.25.2.3, Section 8.3.3.25.2.4, Section 8.3.3.2, Section 8.3.3.3 Table 8.9 AMS: Data Reset AMS Message Sequence Conditions AMS Ref State Machine Ref DFP Initiated Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.1 Section 8.3.3.5.1, Section 8.3.3.5.2 DFP Receives Data Reset where the DFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.2 DFP Initiated Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by DFP Section 8.3.2.5.3 DFP Receives Data Reset where the UFP is the VCONN Source 1. Data_Reset Message 2. Accept Message 3. PS_RDY Message 4. Data_Reset_Complete Message Started by UFP Section 8.3.2.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 435 8.3.2.1.3.6 AMS: Power Role Swap 8.3.2.1.3.7 AMS: Fast Role Swap Table 8.10 AMS: Power Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.7.1.1, Section 8.3.2.2.1.1 Section 8.3.3.19.3, Section 8.3.3.19.4, Section 8.3.3.2, Section 8.3.3.3 Source Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.1.2 Source Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.1.1 Sink Initiated Power Role Swap (Accept) 1. PR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.7.2.1, Section 8.3.2.2.1.1 Sink Initiated Power Role Swap (Reject) 1. PR_Swap Message 2. Reject Message Section 8.3.2.7.2.2 Sink Initiated Power Role Swap (Wait) 1. PR_Swap Message 2. Wait Message Section 8.3.2.7.2.3 Table 8.11 AMS: Fast Role Swap AMS Message Sequence Conditio ns AMS Ref State Machine Ref Fast Role Swap 1. FR_Swap Message 2. Accept Message 3. PS_RDY Message 4. PS_RDY Message 5. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.8, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3, Section 8.3.3.19.5, Section 8.3.3.19.6 Page 436 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.8 AMS: Data Role Swap Table 8.12 AMS: Data Role Swap AMS Message Sequence Conditions AMS Ref State Machine Ref Data Role Swap, Initiated by UFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.1.1 Section 8.3.3.19.1, Section 8.3.3.19.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.2.3 Data Role Swap, Initiated by DFP Operating as Source (Accept) 1. DR_Swap Message 2. Accept Message Started by Source Section 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Sink (Accept) 1. DR_Swap Message 2. Accept Message Started by Sink Section 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Reject) 1. DR_Swap Message 2. Reject Message Section 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Wait) 1. DR_Swap Message 2. Wait Message Section 8.3.2.9.4.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 437 8.3.2.1.3.9 AMS: VCONN Swap 8.3.2.1.3.10 AMS: Alert Table 8.13 AMS: VCONN Swap AMS Message Sequence Conditions AMS Ref State Machine Ref VCONN Source Swap, initiated by VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by VCONN Source Section 8.3.2.10.1.1 Section 8.3.3.20 VCONN Source Swap, initiated by VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.1.3 VCONN Source Swap, initiated by non- VCONN Source (Accept) 1. VCONN_Swap Message 2. Accept Message 3. PS_RDY Message Started by non-VCONN Source Section 8.3.2.10.2.1 VCONN Source Swap, initiated by non- VCONN Source (Reject) 1. VCONN_Swap Message 2. Reject Message Section 8.3.2.10.2.2 VCONN Source Swap, initiated by non- VCONN Source (Wait) 1. VCONN_Swap Message 2. Wait Message Section 8.3.2.10.2.3 Table 8.14 AMS: Alert AMS Message Sequence Conditions AMS Ref AMS Ref Source sends Alert to a Sink (SenderResponseTi mer Timeout) 1. Alert Message Started by Source Section 8.3.2.11.1.1 Section 8.3.3.7.1, Section 8.3.3.7.2 Source sends Alert to a Sink (Get_Status Message) 1. Alert Message 2. Sink Gets Source Status AMS Sink sends Alert to a Source (SenderResponseTi mer Timeout) 1. Alert Message Started by Sink Section 8.3.2.11.1.2 Section 8.3.3.7.3, Section 8.3.3.7.4 Sink sends Alert to a Source (Get_Status Message) 1. Alert Message 2. Source Gets Sink Status AMS Page 438 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.11 AMS: Status 8.3.2.1.3.12 AMS: Source/Sink Capabilities (SPR) Table 8.15 AMS: Status AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Status 1. Get_Status Message 2. Status Message Started by Sink Started by Source Section 8.3.2.11.2.1, Section 8.3.2.11.2.2 Section 8.3.3.10.1, Section 8.3.3.10.2 Source Gets Sink Status 1. Get_Status Message 2. Status Message VCONN Source Gets Cable Plug Status 1. Get_Status Message 2. Status Message Started by VCONN Source Started by Sink Section 8.3.2.11.2.3, Section 8.3.2.11.2.4 Sink Gets Source PPS Status 1. Get_PPS_Status Message 2. PPS_Status Message Section 8.3.3.10.3, Section 8.3.3.10.4 Table 8.16 AMS: Source/Sink Capabilities (SPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Capabilities (EPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Sink Section 8.3.2.11.3.1.1, Section 8.3.2.2.1.3.1, Section 8.3.2.2.1.3.2, Section 8.3.2.2.1.3.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets Source Capabilities (Accept in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Accept) AMS Sink Gets Source Capabilities (Reject in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Reject) AMS Sink Gets Source Capabilities (Wait in SPR Mode) 1. Get_Source_Cap Message 2. Source_Capabilities Message 3. In SPR Mode only: SPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap Message 2. Source_Capabilities Message Started by Source Section 8.3.2.11.3.1.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink Capabilities 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Source Section 8.3.2.11.3.1.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap Message 2. Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.1.4 Section 8.3.3.19.9, Section 8.3.3.19.8 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 439 8.3.2.1.3.13 AMS: Source/Sink Capabilities (EPR) Table 8.17 AMS: Source/Sink Capabilities (EPR) AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets EPR Source Capabilities (SPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Sink Section 8.3.2.11.3.2.1, Section 8.3.2.2.2.5.1, Section 8.3.2.2.2.5.2, Section 8.3.2.2.2.5.3 Section 8.3.3.2, Section 8.3.3.3, Sink Gets EPR Source Capabilities (Accept in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Accept) AMS Sink Gets EPR Source Capabilities (Reject in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Reject) AMS Sink Gets EPR Source Capabilities (Wait in EPR Mode) 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message 3. In EPR Mode only: EPR Sink Makes Request (Wait) AMS Dual-Role Power Source Gets Source Capabilities from a Dual-Role Power EPR Sink 1. EPR_Get_Source_Cap Message 2. EPR_Source_Capabilities Message Started by Source Section 8.3.2.11.3.2.2 Section 8.3.3.19.7, Section 8.3.3.19.10 Source Gets Sink EPR Capabilities 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Source Section 8.3.2.11.3.2.3 Section 8.3.3.2, Section 8.3.3.3, Dual-Role Power Sink Get Sink EPR Capabilities from a Dual-Role Power Source 1. EPR_Get_Sink_Cap Message 2. EPR_Sink_Capabilities Message Started by Sink Section 8.3.2.11.3.2.4 Section 8.3.3.19.8, Section 8.3.3.19.9 Page 440 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.14 AMS: Extended Capabilities 8.3.2.1.3.15 AMS: Battery Capabilities Table 8.18 AMS: Extended Capabilities AMS Interruptible Message Sequence Conditions AMS Ref Sink Gets Source Extended Capabilities 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.4.1 Section 8.3.3.8.1, Section 8.3.3.8.2 Dual-Role Power Source Gets Source Extended Capabilities from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.4.2 Section 8.3.3.19.11, Section 8.3.3.19.12 Source Gets Sink Extended Capabilities 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Source Section 8.3.2.11.4.3 Section 8.3.3.8.3, Section 8.3.3.8.4 Dual-Role Power Sink Gets Sink Extended Capabilities from a Dual-Role Power Source 1. Get_Sink_Cap_Extended Message 2. Sink_Capabilities_Extended Message Started by Sink Section 8.3.2.11.4.4 Section 8.3.3.19.13, Section 8.3.3.19.14 Table 8.19 AMS: Battery Capabilities AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Sink Section 8.3.2.11.5.1 Section 8.3.3.11.1, Section 8.3.3.11.2 Source Gets Battery Capabilities 1. Get_Battery_Cap Message 2. Battery_Capabilities Message Started by Source Section 8.3.2.11.5.2 Sink Gets Battery Status 1. Get_Battery_Status Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.3 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Battery Status 1. Get_Battery_Cap Message 2. Battery_Status Message Started by Sink Section 8.3.2.11.5.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 441 8.3.2.1.3.16 AMS: Manufacturer Information 8.3.2.1.3.17 AMS: Country Codes 8.3.2.1.3.18 AMS: Country Information Table 8.20 AMS: Manufacturer Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Port Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.1 Section 8.3.3.12.1, Section 8.3.3.12.2 Sink Gets Port Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.2 Source Gets Battery Manufacturer Information from a Sink 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Source Section 8.3.2.11.6.3 Sink Gets Battery Manufacturer Information from a Source 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by Sink Section 8.3.2.11.6.4 VCONN Source Gets Manufacturer Information from a Cable Plug 1. Get_Manufacturer_Info Message 2. Manufacturer_Info Message Started by VCONN Source Section 8.3.2.11.6.5 Table 8.21 AMS: Country Codes AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Codes from a Sink 1. Get_Country_Codes Message 2. Country_Codes Message Started by Source Section 8.3.2.11.7.1 Section 8.3.3.14.1, Section 8.3.3.14.2 Sink Gets Country Codes from a Source 1. Get_Country_Codes Message 2. Country_Codes Message Started by Sink Section 8.3.2.11.7.2 VCONN Source Gets Country Codes from a Cable Plug 1. Get_Country_Codes Message 2. Country_Codes Message Started by VCONN Source Section 8.3.2.11.7.3 Table 8.22 AMS: Country Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Country Information from a Sink 1. Get_Country_Info Message 2. Country_Info Message Started by Source Section 8.3.2.11.8.1 Section 8.3.3.14.3, Section 8.3.3.14.4 Sink Gets Country Information from a Source 1. Get_Country_Info Message 2. Country_Info Message Started by Sink Section 8.3.2.11.8.2 VCONN Source Gets Country Information from a Cable Plug 1. Get_Country_Info Message 2. Country_Info Message Started by VCONN Source Section 8.3.2.11.8.3 Page 442 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.19 AMS: Revision Information 8.3.2.1.3.20 AMS: Source Information 8.3.2.1.3.21 AMS: Security Table 8.23 AMS: Revision Information AMS Message Sequence Conditions AMS Ref State Machine Ref Source Gets Revision Information from a Sink 1. Get_Revision Message 2. Revision Message Started by Source Section 8.3.2.11.9.1 Section 8.3.3.15.1, Section 8.3.3.15.2 Sink Gets Revision Information from a Source 1. Get_Revision Message 2. Revision Message Started by Sink Section 8.3.2.11.9.2 VCONN Source Gets Revision Information from a Cable Plug 1. Get_Revision Message 2. Revision Message Started by VCONN Source Section 8.3.2.11.9.1 Table 8.24 AMS: Source Information AMS Message Sequence Conditions AMS Ref State Machine Ref Sink Gets Source Information 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Sink Section 8.3.2.11.10.1 Section 8.3.3.9.1, Section 8.3.3.9.2 Dual-Role Power Source Gets Source Information from a Dual-Role Power Sink 1. Get_Source_Cap_Extended Message 2. Source_Capabilities_Extended M essage Started by Source Section 8.3.2.11.10.2 Section 8.3.3.19.15, Section 8.3.3.19.16 Table 8.25 AMS: Security AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests security exchange with Sink 1. Security_Request Message Started by Source Section 8.3.2.12.1 Section 8.3.3.17.1, Section 8.3.3.17.2, Section 8.3.3.17.3 Sink requests security exchange with Source 1. Security_Request Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Request Message Started by VCONN Source Section 8.3.2.12.3 Source responds to security exchange with Sink 1. Security_Response Message Started by Source Section 8.3.2.12.1 Sink responds to security exchange with Source 1. Security_Response Message Started by Sink Section 8.3.2.12.2 VCONN Source requests security exchange with Cable Plug 1. Security_Response Message Started by VCONN Source Section 8.3.2.12.3 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 443 8.3.2.1.3.22 AMS: Firmware Update Table 8.26 AMS: Firmware Update AMS Message Sequence Conditions AMS Ref State Machine Ref Source requests firmware update exchange with Sink 1. Firmware_Update_Request Message Started by Source Section 8.3.2.13.1 Section 8.3.3.18.1, Section 8.3.3.18.2, Section 8.3.3.18.3 Sink requests firmware update exchange with Source 1. Firmware_Update_Request Message Started by Sink Section 8.3.2.13.2 VCONN Source requests firmware update exchange with Cable Plug 1. Firmware_Update_Request Message Started by VCONN Source Section 8.3.2.13.3 Source responds to firmware update exchange with Sink 1. Firmware_Update_Response Message Started by Source Section 8.3.2.13.1 Sink responds to firmware update exchange with Source 1. Firmware_Update_Response Message Started by Sink Section 8.3.2.13.2 VCONN Source responds to firmware update exchange with Cable Plug 1. Firmware_Update_Response Message Started by VCONN Source Section 8.3.2.13.3 Page 444 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.23 AMS: Structured VDM Table 8.27 AMS: Structured VDM AMS Message Sequence Conditions AMS Ref State Machine Ref Initiator to Responder Discover Identity (ACK) 1. Discover Identity REQ Command 2. Discover Identity ACK Command Started by Initiator Section 8.3.2.14.1.1 Section 8.3.3.21.1, Section 8.3.3.22.1 Initiator to Responder Discover Identity (NAK) 1. Discover Identity REQ Command 2. Discover Identity NAK Command Section 8.3.2.14.1.2 Initiator to Responder Discover Identity (BUSY) 1. Discover Identity REQ Command 2. Discover Identity BUSY Command Section 8.3.2.14.1.3 Initiator to Responder Discover SVIDs (ACK) 1. Discover SVIDs REQ Command 2. Discover SVIDs ACK Command Section 8.3.2.14.2.1 Section 8.3.3.21.2, Section 8.3.3.22.2 Initiator to Responder Discover SVIDs (NAK) 1. Discover SVIDs REQ Command 2. Discover SVIDs NAK Command Section 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (BUSY) 1. Discover SVIDs REQ Command 2. Discover SVIDs BUSY Command Section 8.3.2.14.2.3 Initiator to Responder Discover Modes (ACK) 1. Discover Modes REQ Command 2. Discover Modes ACK Command Section 8.3.2.14.3.1 Section 8.3.3.21.3, Section 8.3.3.22.3 Initiator to Responder Discover Modes (NAK) 1. Discover Modes REQ Command 2. Discover Modes NAK Command Section 8.3.2.14.3.2 Initiator to Responder Discover Modes (BUSY) 1. Discover Modes REQ Command 2. Discover Modes BUSY Command Section 8.3.2.14.3.3 DFP to UFP Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Started by DFP Section 8.3.2.14.4.1 Section 8.3.3.23.1, Section 8.3.3.24.1 DFP to UFP Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.2 Section 8.3.3.23.2, Section 8.3.3.24.2 DFP to Cable Plug Enter Mode 1. Enter Mode REQ Command 2. Enter Mode ACK Command Section 8.3.2.14.4.3 Section 8.3.3.23.1, Section 8.3.3.25.4.1 DFP to Cable Plug Exit Mode 1. Exit Mode REQ Command 2. Exit Mode ACK Command Section 8.3.2.14.4.4 Section 8.3.3.23.2, Section 8.3.3.25.4.2 Initiator to Responder Attention 1. Attention REQ Command Started by Initiator Section 8.3.2.14.4.5 Section 8.3.3.21.4, Section 8.3.3.22.4 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 445 8.3.2.1.3.24 AMS: Built-In Self-Test (BIST) 8.3.2.1.3.25 AMS: Enter USB 8.3.2.1.3.26 AMS: Unstructured VDM Table 8.28 AMS: Built-In Self-Test (BIST) AMS Message Sequence Conditions AMS Ref State Machine Ref BIST Carrier Mode 1. BIST (BIST Carrier Mode) Message Started by Tester Section 8.3.2.15.1 Section 8.3.3.27.1 BIST Test Data Mode 1. BIST (BIST Test Data) Message Section 8.3.2.15.2 Section 8.3.3.27.2 BIST Shared Capacity Test Mode 1. BIST (BIST Shared Test Mode Entry) Message 2. Series of Messages 3. BIST (BIST Shared Test Mode Exit) Message Section 8.3.2.15.3 Section 8.3.3.27.3 Table 8.29 AMS: Enter USB AMS Message Sequence Conditions AMS Ref State Machine Ref UFP Entering USB4® Mode (Accept) 1. Enter_USB Message 2. Accept Message Started by DFP Section 8.3.2.16.1.1 Section 8.3.3.16.1, Section 8.3.3.16.2 UFP Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.1.2 UFP Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.1.3 Cable Plug Entering USB4 Mode (Accept) 1. Enter_USB Message 2. Accept Message Section 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Reject) 1. Enter_USB Message 2. Reject Message Section 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Wait) 1. Enter_USB Message 2. Wait Message Section 8.3.2.16.2.3 Table 8.30 AMS: Unstructured VDM AMS Message Sequence AMS Ref State Machine Ref Unstructured VDM 1. Unstructured Vendor_Defined Message Section 8.3.2.17.1 VDEM 1. Vendor_Defined_Extended Message Section 8.3.2.17.2 Page 446 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.1.3.27 AMS: Hard Reset Table 8.31 AMS: Hard Reset AMS Interruptibl e Message Sequence Conditions AMS Ref State Machine Ref Source Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.1, Section 8.3.2.2.1.1 Section 8.3.3.2, Section 8.3.3.3 Sink Initiated Hard Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Sink Section 8.3.2.6.2, Section 8.3.2.2.1.1 Source Initiated Hard Reset – Sink Long Reset No 1. Hard Reset Signaling 2. SPR Explicit Contract Negotiation AMS Started by Source Section 8.3.2.6.3, Section 8.3.2.2.1.1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 447 8.3.2.2 Power Negotiation 8.3.2.2.1 SPR 8.3.2.2.1.1 SPR Explicit Contract Negotiation 8.3.2.2.1.1.1 SPR Explicit Contract Negotiation (Accept) Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through 5 distinct phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  For SPR PPS operation:  the Source starts its keep alive timer.  the Sink starts its request timer to send periodic Request Messages. Page 448 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.5 Successful Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer For PPS operation start PPSRequestTimer New Power level Evaluate Capabilities Detect plug type Evaluate Request Prepare for new power Source Sink Cable Capabilities detected Plug type detected For PPS operation start PPSTimeoutTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 449 Table 8.32, "Steps for a successful Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.5, "Successful Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.32 Steps for a successful Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 450 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.32 Steps for a successful Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 451 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. New Power Level Negotiated Table 8.32 Steps for a successful Power Negotiation Step Source Sink Page 452 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.1.2 SPR Explicit Contract Negotiation (Reject) Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Reject Message. Figure 8.6 Rejected Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 453 Table 8.33, "Steps for a rejected Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.6, "Rejected Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Page 454 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.33 Steps for a rejected Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 455 8.3.2.2.1.1.3 SPR Explicit Contract Negotiation (Wait) Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in SPR Mode. The Negotiation goes through the following phases:  The Source sends out its power Capabilities in a Source_Capabilities Message.  The Sink evaluates these Capabilities, and, in the request, phase selects one power level by sending a Request Message.  The Source evaluates the request and rejects the request with a Wait Message. Figure 8.7 Wait response to Fixed, Variable or Battery SPR Power Negotiation : Source Policy Engine : Protocol 1: Send Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: Capabilities 3: Capabilities + CRC 4: Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Capabilities sent Start SenderResponseTimer 10: Send Request 11: Request 12: Request + CRC 13: Request Check MessageID against local copy Store copy of MessageID 14: Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Evaluate Capabilities Detect plug type Evaluate Request Source Sink Cable Capabilities detected Plug type detected Page 456 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.34, "Steps for a Wait response to a Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.7, "Wait response to Fixed, Variable or Battery SPR Power Negotiation" above. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink 1 The Cable Capabilities or Plug Type are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the Source_Capabilities Message sent by the Source, detects the plug type if this is necessary (see Section 4.4, "Cable Type Detection") and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the Request Message and passes to PHY Layer. 12 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 457 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.34 Steps for a Wait response to a Power Negotiation Step Source Sink Page 458 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.2 SPR PPS Keep Alive This is an example of SPR PPS keep alive operation during an Explicit Contract with SPR PPS as the APDO. Figure 8.8, "SPR PPS Keep Alive" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.8 SPR PPS Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer Stop PPSCommTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer Stop PPSRequestTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Send Ping if required to maintain activity Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer Start PPSRequestTimer New Power level Evaluate Request Prepare for new power Source Sink PPSRequestTimer Timeout Start PPSCommTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 459 Table 8.35, "Steps for SPR PPS Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.8, "SPR PPS Keep Alive" above. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink 1 The SinkPPSPeriodicTimer times out in the Policy Engine. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourcePPSCommTimer. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Page 460 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. When in SPR PPS Mode the Policy Engine starts the SinkPPSPeriodicTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 27 When in SPR PPS Mode the Policy Engine starts the SourcePPSCommTimer. Table 8.35 Steps for SPR PPS Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 461 8.3.2.2.1.3 SPR Sink Makes Request 8.3.2.2.1.3.1 SPR Sink Makes Request (Accept) This is an example of SPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.9, "SPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.9 SPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate Request Prepare for new power Source Sink Page 462 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.36, "Steps for SPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.9, "SPR Sink Makes Request (Accept)" above. Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 463 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.36 Steps for SPR Sink Makes Request (Accept) Step Source Sink Page 464 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.1.3.2 SPR Sink Makes Request (Reject) This is an example of SPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.10, "SPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.10 SPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 465 Table 8.37, "Steps for SPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.10, "SPR Sink Makes Request (Reject)" above. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 466 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.37 Steps for SPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 467 8.3.2.2.1.3.3 SPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.11, "SPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.11 SPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send Request 2: Request 3: Request + CRC 4: Request Check MessageID against local copy Store copy of MessageID 5: Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate Request Source Sink Page 468 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.38, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.11, "SPR Sink Makes Request (Wait)" above. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form a Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 469 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.38 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 470 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2 EPR 8.3.2.2.2.1 Entering EPR Mode 8.3.2.2.2.1.1 Entering EPR Mode (Success) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process succeeds. Figure 8.12, "Entering EPR Mode (Success)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.12 Entering EPR Mode (Success) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode entered Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is EPR Capable 21: Send EPR_Mode (Enter Succeeded) 22: EPR_Mode (Enter Succeeded) 23: EPR_Mode (Enter Succeeded) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Succeeded) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Succeeded) 25: EPR_Mode (Enter Succeeded) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 471 Table 8.39, "Steps for Entering EPR Mode (Success)" below provides a detailed explanation of what happens at each labeled step in Figure 8.12, "Entering EPR Mode (Success)" above. Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter)Source_Capabilities Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 472 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source is now the VCONN Source and has determined that the Sink and the cable are EPR Capable. The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Succeeded) Message. 22 Protocol Layer creates the EPR_Mode (Enter Succeeded) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Succeeded) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Succeeded) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Succeeded) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Succeeded) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Entered Table 8.39 Steps for Entering EPR Mode (Success) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 473 8.3.2.2.2.1.2 Entering EPR Mode (Failure due to non-EPR cable) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to the cable not being capable of EPR. Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.13 Entering EPR Mode (Failure due to non-EPR cable) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source becomes VCONN Source 20: Source reads Cable E-Marker to determine EPR capability – Cable is not EPR Capable 21: Send EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) 23: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 26: GoodCRC 27: GoodCRC + CRC 28: GoodCRC 29: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 24: EPR_Mode (Enter Failed) 25: EPR_Mode (Enter Failed) received Page 474 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.40, "Steps for Entering EPR Mode (Failure due to non-EPR cable)" below provides a detailed explanation of what happens at each labeled step in Figure 8.13, "Entering EPR Mode (Failure due to non-EPR cable)" above. Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 475 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". 20 The Source performs Cable Discovery to determine whether the cable supports EPR; cable is not EPR Capable. The Cable Discovery process is described in Section 8.3.2.14.1, "Discover Identity". 21 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 22 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 23 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 24 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 25 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 26 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 27 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 28 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 29 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.40 Steps for Entering EPR Mode (Failure due to non-EPR cable) Step Sink Source Page 476 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.1.3 Entering EPR Mode (Failure of VCONN Swap) This is an example of an Enter EPR Mode operation where the Sink requests EPR Mode when this process fails due to a failure of the VCONN Swap process. Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter EPR process. Figure 8.14 Entering EPR Mode (Failure of VCONN Swap) : Protocol 1: Send EPR_Mode (Enter) : PHY : PHY : Protocol 2: EPR_Mode (Enter) 3: EPR_Mode (Enter) + CRC 4: EPR_Mode (Enter) Start CRCReceiveTimer 5: EPR_Mode (Enter) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Enter) sent Start SinkEPREnterTimer Start SenderResponseTimer 10: Send EPR_Mode (Enter Acknowledged) 11: EPR_Mode (Enter Acknowledged) 12: EPR_Mode (Enter Acknowledged) + CRC Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Mode (Enter Acknowledged) sent Start CRCReceiveTimer : Policy Engine : Policy Engine EPR Mode is not entered. Sink Initiates Soft Reset. Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: EPR_Mode (Enter Acknowledged) 14: EPR_Mode (Enter Acknowledged) received 19: Optional VCONN Swap Process – Source fails to become VCONN Source 20: Send EPR_Mode (Enter Failed) 21: EPR_Mode (Enter Failed) 22: EPR_Mode (Enter Failed) + CRC Stop SinkEPREnterTimer 25: GoodCRC 26: GoodCRC + CRC 27: GoodCRC 28: EPR_Mode (Enter Failed) sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 23: EPR_Mode (Enter Failed) 24: EPR_Mode (Enter Failed) received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 477 Table 8.41, "Steps for Entering EPR Mode (Failure of VCONN Swap)" below provides a detailed explanation of what happens at each labeled step in Figure 8.14, "Entering EPR Mode (Failure of VCONN Swap)" above. Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Enter) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Enter) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Enter) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Enter) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Enter) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Enter) Message was successfully sent. The Policy Engine starts the SenderResponseTimer and the SinkEPREnterTimer. 10 Policy Engine evaluates the EPR_Mode (Enter) Message sent by the Sink. It tells the Protocol Layer to form a EPR_Mode (Enter Acknowledged) Message. 11 Protocol Layer creates the EPR_Mode (Enter Acknowledged) Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Mode (Enter Acknowledged) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Acknowledged) Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Acknowledged) Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Acknowledged) information to the Policy Engine. The Policy Engine stops the SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 478 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Acknowledged) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. 19 If the Source is not the VCONN Source the Source initiates the VCONN Swap process as described in Section 8.3.2.10, "VCONN Swap". In this case the VCONN Swap process fails. 20 The Source determines that there has been a failure or incompatibility during the EPR process (see Section 6.4.10, "EPR_Mode Message"). The Policy Engine tells the Protocol Layer to form a EPR_Mode (Enter Failed) Message. 21 Protocol Layer creates the EPR_Mode (Enter Failed) Message and passes to PHY Layer. 22 PHY Layer receives the EPR_Mode (Enter Failed) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Mode (Enter Failed) Message. Starts CRCReceiveTimer. 23 PHY Layer removes the CRC and forwards the EPR_Mode (Enter Failed) Message to the Protocol Layer. 24 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Failed) information to the Policy Engine. The Policy Engine stops the SinkEPREnterTimer. 25 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 26 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 27 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 28 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Mode (Enter Failed) Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode is not entered. Sink Initiates Soft Reset Table 8.41 Steps for Entering EPR Mode (Failure of VCONN Swap) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 479 8.3.2.2.2.2 EPR Explicit Contract Negotiation 8.3.2.2.2.2.1 EPR Explicit Contract Negotiation (Accept) Figure 8.15, "Successful Fixed EPR Power Negotiation" illustrates an example of a successful Message flow while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with an Accept Message.  The Source transitions to the new power level and then informs the Sink by sending a PS_RDY Message.  The Sink starts using the new power level.  the Source starts its keep alive timer  the Sink starts its request timer to send periodic EPR_KeepAlive Messages Page 480 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.15 Successful Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Accept 20: Accept 21: Accept + CRC 22: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Accept received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Stop PSTransitionTimer Start SinkEPRKeepAliveTimer New Power level Evaluate EPR Capabilities Evaluate EPR Request Prepare for new power Source Sink Cable EPR_Source_Capabilities detected Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 481 Table 8.42, "Steps for a successful EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.15, "Successful Fixed EPR Power Negotiation" above. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 482 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form an Accept Message. 20 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Accept Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 28 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 29 The Protocol Layer forms the PS_RDY Message. 30 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer forwards the PS_RDY Message to the Protocol Layer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 483 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. The Policy Engine starts the SinkEPRKeepAliveTimer. 33 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 34 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 35 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 36 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 37 When in EPR operation the Policy Engine starts the SourceEPRKeepAliveTimer. Table 8.42 Steps for a successful EPR Power Negotiation Step Source Sink Page 484 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.2.2 EPR Explicit Contract Negotiation (Reject) Figure 8.16, "Rejected Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is rejected while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Reject Message. Figure 8.16 Rejected Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Reject 20: Reject 21: Reject + CRC 22: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Reject received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Reject sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 485 Table 8.43, "Steps for a Rejected EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.16, "Rejected Fixed EPR Power Negotiation" above. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 486 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides it can’t meet the request. It tells the Protocol Layer to form a Reject Message. 20 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Reject Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Reject Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.43 Steps for a Rejected EPR Power Negotiation Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 487 8.3.2.2.2.2.3 EPR Explicit Contract Negotiation (Wait) Figure 8.17, "Wait response to Fixed EPR Power Negotiation" illustrates an example of a Message flow where the request is responded to with wait while negotiating an Explicit Contract in EPR Mode. The Negotiation goes through several distinct phases:  The Source sends out its power Capabilities in an EPR_Source_Capabilities Message.  The Sink evaluates these Capabilities and, in the request phase, selects one power level by sending an EPR_Request Message.  The Source evaluates the request and accepts the request with a Wait Message. Figure 8.17 Wait response to Fixed EPR Power Negotiation : Source Policy Engine : Protocol 1: Send EPR_Source_Capabilities : PHY : PHY : Protocol : Sink Policy Engine 2: EPR_Source_Capabilities 3: EPR_Source_Capabilities + CRC 4: EPR_Source_Capabilities Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Source_Capabilities received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: EPR_Source_Capabilities sent Start SenderResponseTimer 10: Send EPR_Request 11: EPR_Request 12: EPR_Request + CRC 13: EPR_Request Check MessageID against local copy Store copy of MessageID 14: EPR_Request received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 19: Send Wait 20: Wait 21: Wait + CRC 22: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Wait received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Wait sent Stop SenderResponseTimer Start PSTransitionTimer Reduce current Evaluate EPR Capabilities Evaluate EPR Request Source Sink Cable EPR_Source_Capabilities detected Page 488 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.44, "Steps for a Wait response to an EPR Power Negotiation" below provides a detailed explanation of what happens at each labeled step in Figure 8.17, "Wait response to Fixed EPR Power Negotiation" above. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink 1 The Cable Capabilities are detected if these are not already known (see Section 4.4, "Cable Type Detection"). Policy Engine directs the Protocol Layer to send a EPR_Source_Capabilities Message that represents the power supply’s present capabilities. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Source_Capabilities Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Source_Capabilities Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the EPR_Source_Capabilities Message sent by the Source and selects which power it would like. It tells the Protocol Layer to form the data (e.g., Power Data Object) that represents its Request into a Message. 11 Protocol Layer creates the EPR_Request Message and passes to PHY Layer. 12 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops SenderResponseTimer. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 489 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 19 Policy Engine evaluates the EPR_Request Message sent by the Sink and decides if it can meet the request. It tells the Protocol Layer to form a Wait Message. 20 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 21 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer forwards the Wait Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a Wait Message has been received. The Policy Engine stops SenderResponseTimer. 24 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 25 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Message. 26 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 27 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.44 Steps for a Wait response to an EPR Power Negotiation Step Source Sink Page 490 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.3 EPR Keep Alive This is an example of keep alive operation during an Explicit Contract in EPR Mode. Figure 8.18, "EPR Keep Alive"shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.18 EPR Keep Alive : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_KeepAlive 2: EPR_KeepAlive 3: EPR_KeepAlive + CRC 4: EPR_KeepAlive Check MessageID against local copy Store copy of MessageID 5: EPR_KeepAlive received Stop SourceEPRKeepAliveTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_KeepAlive sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send EPR_KeepAlive_Ack 11: EPR_KeepAlive_Ack 12: EPR_KeepAlive_Ack + CRC 13: EPR_KeepAlive_Ack Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: EPR_KeepAlive_Ack received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: EPR_KeepAlive_Ack sent Stop SenderResponseTimer Start SinkEPRKeepAliveTimer EPR Mode Continues Evaluate EPR_KeepAlive Source Sink SinkEPRKeepAliveTimer Timeout Stop SinkEPRKeepAliveTimer Start SourceEPRKeepAliveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 491 Table 8.45, "Steps for EPR Keep Alive" below provides a detailed explanation of what happens at each labeled step in Figure 8.18, "EPR Keep Alive" above. Table 8.45 Steps for EPR Keep Alive Step Source Sink 1 The SinkEPRKeepAliveTimer times out in the Policy Engine. The Policy Engine stops the SinkEPRKeepAliveTimer timer and tells the Protocol Layer to form an EPR_KeepAlive Message. 2 The Protocol Layer creates the EPR_KeepAlive Message and passes it to PHY Layer. The Protocol Layer. 3 PHY Layer receives the EPR_KeepAlive Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Request Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_KeepAlive Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. Policy Engine stops the SourceEPRKeepAliveTimer. 6 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 9 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the SinkEPRKeepAliveTimer Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM to evaluate the SourceEPRKeepAliveTimer Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an EPR_KeepAlive_Ack Message. 11 The Protocol Layer forms the EPR_KeepAlive_Ack Message that is passed to the PHY Layer. 12 PHY Layer appends CRC and sends the EPR_KeepAlive_Ack Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_KeepAlive_Ack Message and compares the CRC it calculated with the one sent to verify the Message. 13 PHY Layer forwards the EPR_KeepAlive_Ack Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the SinkEPRKeepAliveTimer. Page 492 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 18 The Protocol Layer informs the Policy Engine that an EPR_KeepAlive_Ack Message was successfully sent. The Policy Engine starts the SourceEPRKeepAliveTimer. EPR Mode Continues Table 8.45 Steps for EPR Keep Alive Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 493 8.3.2.2.2.4 Exiting EPR Mode 8.3.2.2.2.4.1 Exiting EPR Mode (Sink Initiated) This is an example of an Exit EPR Mode operation where the Sink requests EPR Mode to be exited. Figure 8.19, "Exiting EPR Mode (Sink Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.19 Exiting EPR Mode (Sink Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Page 494 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.46, "Steps for Exiting EPR Mode (Sink Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.19, "Exiting EPR Mode (Sink Initiated)" above. Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 495 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.46 Steps for Exiting EPR Mode (Sink Initiated) Step Sink Source Page 496 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.4.2 Exiting EPR Mode (Source Initiated) This is an example of an Exit EPR Mode operation where the Source requests EPR Mode to be exited. Figure 8.20, "Exiting EPR Mode (Source Initiated)" shows the Messages as they flow across the bus and within the devices to accomplish the Exit EPR process. Figure 8.20 Exiting EPR Mode (Source Initiated) : Protocol 1: Send EPR_Mode (Exit) : PHY : PHY : Protocol 2: EPR_Mode (Exit) 3: EPR_Mode (Exit) + CRC 4: EPR_Mode (Exit) Start CRCReceiveTimer 5: EPR_Mode (Exit) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Mode (Exit) sent : Policy Engine : Policy Engine EPR Mode exited Sink Source Check and increment MessageIDCounter Stop CRCReceiveTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Source_Capabilities sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer 13: Source_Capabilities 14: Source_Capabilities received Ports in EPR Mode with SPR PDO Explicit Contract Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 497 Table 8.47, "Steps for Exiting EPR Mode (Source Initiated)" below provides a detailed explanation of what happens at each labeled step in Figure 8.20, "Exiting EPR Mode (Source Initiated)" above. Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source The Port Partners are in an Explicit Contract using an SPR (A)PDO (Voltage <= 20V) 1 The Policy Engine directs the Protocol Layer to generate an EPR_Mode (Exit) Message to request entry to EPR Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer receives the EPR_Mode (Exit) Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the EPR_Mode (Exit) Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the EPR_Mode (Exit) Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Mode (Exit) Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Mode (Exit) Message was successfully sent. 10 Policy Engine evaluates the EPR_Mode (Exit) Message sent by the Sink. It tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Source_Capabilities Message and passes to PHY Layer. Starts CRCReceiveTimer. 12 PHY Layer receives the Source_Capabilities Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the EPR_Mode (Enter Succeeded) information to the Policy Engine. 15 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 16 PHY Layer appends CRC and sends the Message. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. Page 498 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 18 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. EPR Mode Exited. Power Negotiation proceeds as defined in Section 8.3.2.2.1.1, "SPR Explicit Contract Negotiation". Table 8.47 Steps for Exiting EPR Mode (Source Initiated) Step Sink Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 499 8.3.2.2.2.5 EPR Sink Makes Request 8.3.2.2.2.5.1 EPR Sink Makes Request (Accept) This is an example of EPR when a Sink makes a Request which is Accepted during an Explicit Contract. Figure 8.21, "EPR Sink Makes Request (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.21 EPR Sink Makes Request (Accept) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Accept sent Power supply adjusted to negotiated output Stop SenderResponseTimer Start PSTransitionTimer Reduce current 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSTransitionTimer New Power level Evaluate EPR_Request Prepare for new power Source Sink Page 500 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.48, "Steps for EPR Sink Makes Request (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.21, "EPR Sink Makes Request (Accept)" above. Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form an Accept Message. 10 The Protocol Layer forms the Accept Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Accept Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Accept Message has been received. The Policy Engine stops SenderResponseTimer, starts the PSTransitionTimer and reduces its current draw. The DPM prepares the Power supply for transition to the new power level. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 501 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that an Accept Message was successfully sent. Power supply Adjusts its Output to the Negotiated Value 18 The DPM informs the Policy Engine that the power supply has settled at the new operating condition and tells the Protocol Layer to send a PS_RDY Message. 19 The Protocol Layer forms the PS_RDY Message. 20 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 21 PHY Layer forwards the PS_RDY Message to the Protocol Layer. 22 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that a RS_RDY has been received. The Policy Engine stops the PSTransitionTimer. 23 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 24 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 25 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter. Stops the CRCReceiveTimer. 26 The Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. New Power Level Negotiated Table 8.48 Steps for EPR Sink Makes Request (Accept) Step Source Sink Page 502 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.2.2.5.2 EPR Sink Makes Request (Reject) This is an example of EPR when a Sink makes a Request which is Rejected during an Explicit Contract. Figure 8.22, "EPR Sink Makes Request (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.22 EPR Sink Makes Request (Reject) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Reject sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 503 Table 8.49, "Steps for EPR Sink Makes Request (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.22, "EPR Sink Makes Request (Reject)" above. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the EPR_Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides that the Source can’t meet the request. The Policy Engine tells the Protocol Layer to form a Reject Message. 10 The Protocol Layer forms the Reject Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Reject Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Reject Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Page 504 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Reject Message was successfully sent. Table 8.49 Steps for EPR Sink Makes Request (Reject) Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 505 8.3.2.2.2.5.3 EPR Sink Makes Request (Wait) This is an example of SPR when a Sink makes a Request which is responded to with a Wait Message during an Explicit Contract. Figure 8.23, "EPR Sink Makes Request (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the keep alive. Figure 8.23 EPR Sink Makes Request (Wait) : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine 1: Send EPR_Request 2: EPR_Request 3: EPR_Request + CRC 4: EPR_Request Check MessageID against local copy Store copy of MessageID 5: EPR_Request received Stop SenderResponseTimer 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: EPR_Request sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Wait sent Stop SenderResponseTimer Evaluate EPR_Request Source Sink Page 506 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.50, "Steps for SPR Sink Makes Request (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.23, "EPR Sink Makes Request (Wait)" above. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink 1 DPM tells the Policy Engine to request a different power level. The Policy Engine tells the Protocol Layer to form an EPR_Request Message. The Protocol Layer creates the EPR_Request Message and passes it to PHY Layer. 2 PHY Layer receives the EPR_Request Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the EPR_Request Message. Starts CRCReceiveTimer. 3 PHY Layer removes the CRC and forwards the EPR_Request Message to the Protocol Layer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer passes the Request information to the Policy Engine. 5 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. 6 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 7 PHY Layer forwards the GoodCRC Message to the Protocol Layer. 8 The Protocol Layer verifies and increments the MessageIDCounter. It informs the Policy Engine that the Request Message was successfully sent. The Protocol Layer stops the CRCReceiveTimer. The Policy Engine starts SenderResponseTimer. 9 Policy Engine requests the DPM to evaluate the EPR_Request Message sent by the Sink and decides if the Source can meet the request. The Policy Engine tells the Protocol Layer to form a Wait Message. 10 The Protocol Layer forms the Wait Message that is passed to the PHY Layer. 11 PHY Layer appends CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. 12 PHY Layer forwards the Wait Message to the Protocol Layer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. Protocol Layer informs the Policy Engine that an Wait Message has been received. The Policy Engine informs the DPM that the Request has been rejected. 14 The Protocol Layer generates a GoodCRC Message and passes it to its PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 507 15 PHY Layer receives the GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 16 PHY Layer forwards the GoodCRC Message to the Protocol Layer. The Protocol Layer verifies and increments the MessageIDCounter and stops the CRCReceiveTimer. 17 The Protocol Layer informs the Policy Engine that a Wait Message was successfully sent. Table 8.50 Steps for SPR Sink Makes Request (Wait) Step Source Sink Page 508 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.3 Unsupported Message This is an example of the response to an Unsupported Message. Figure 8.24, "Unsupported message" shows the Messages as they flow across the bus and within the devices. Figure 8.24 Unsupported message : Protocol 1: Send Message : PHY : PHY : Protocol 2: Message 3: Message + CRC 4: Message Start CRCReceiveTimer 5: Message received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Message sent Start SenderResponseTimer 10: Send Not_supported 11: Not_supported 12: Not_supported + CRC 13: Not_supported 14: Not_supported received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Not_supported sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Message Initiator Message Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 509 Table 8.51, "Steps for an Unsupported Message" below provides a detailed explanation of what happens at each labeled step in Figure 8.24, "Unsupported message" above. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder 1 The Policy Engine directs the Protocol Layer to generate a Message. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Message. Starts CRCReceiveTimer. PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Not_Supported Message. 11 Protocol Layer creates the Not_Supported Message and passes to PHY Layer. 12 PHY Layer receives the Not_Supported Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Not_Supported Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Not_Supported Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 510 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Not_Supported Message was successfully sent. Table 8.51 Steps for an Unsupported Message Step Message Initiator Message Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 511 8.3.2.4 Soft Reset This is an example of a Soft Reset operation. Figure 8.25, "Soft Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Soft Reset. Figure 8.25 Soft Reset : Protocol 1: Send Soft Reset : PHY : PHY : Protocol 2: Soft Reset 3: Soft Reset + CRC 4: Soft Reset Start CRCReceiveTimer 5: Soft Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Soft Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Reset Complete, Explicit Contract negotiation Reset Initiator Reset Responder Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 512 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.52, "Steps for a Soft Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.25, "Soft Reset" above. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder 1 The Policy Engine directs the Protocol Layer to generate a Soft_Reset Message to request a Soft Reset. 2 Protocol Layer resets MessageIDCounter, stored MessageID and RetryCounter. Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Soft_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Soft_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Soft_Reset Message to the Protocol Layer. 5 Protocol Layer does not check the MessageID in the incoming Message and resets MessageIDCounter, stored MessageID and RetryCounter. The Protocol Layer forwards the received Soft_Reset Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Soft_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 513 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The reset is complete and protocol communication can restart. Port Partners perform an Explicit Contract Negotiation to re- synchronize their state machines. Table 8.52 Steps for a Soft Reset Step Reset Initiator Reset Responder Page 514 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5 Data Reset 8.3.2.5.1 DFP Initiated Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP is also the VCONN Source and initiates a Data Reset. Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.26 DFP Initiated Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Tell DPM to perform Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete Start CRCReceiveTimer 23: Data_Reset_Complete received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 515 Table 8.53, "Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.26, "DFP Initiated Data Reset where the DFP is the VCONN Source" above. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to perform a Data Reset. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 516 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The Data Reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.53 Steps for a DFP Initiated Data Reset where the DFP is the VCONN Source Step DFP/VCONN Source (Reset Initiator) UFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 517 8.3.2.5.2 DFP Receives Data Reset where the DFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and is the VCONN Source. Figure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.27 DFP Receives Data Reset where the DFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Tell DPM to perform a Data Reset 19: Send Data_Reset_Complete 20: Data_Reset_Complete 21: Data_Reset_Complete + CRC 22: Data_Reset_Complete 23: Data_Reset_Complete received Inform DPM Data Reset is complete 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Page 518 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.54, "Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource" below provides a detailed explanation of what happens at each labeled step in FFigure 8.27, "DFP Receives Data Reset where the DFP is the VCONN Source" above. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Data Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer. The DPM proceeds to cycle VCONN and then reset the data connection. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 519 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the DPM to perform a Data Reset. 19 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.54 Steps for a DFP Receiving a Data Reset where the DFP is the VCONNSource Step UFP (Reset Initiator) DFP/VCONN Source (Reset Responder) Page 520 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.3 DFP Initiated Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP initiates a Data Reset and the UFP is the VCONN Source. Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.28 DFP Initiated Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Stop SenderResponseTimer Start VCONNDischargeTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset Request DPM to turn off VCONN DPM indicates VCONN is off 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete Start CRCReceiveTimer 32: Data_Reset_Complete received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Inform DPM that Data_Reset_Complete has been sent Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset_Complete has been received DPM indicates that Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 521 Table 8.55, "Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.28, "DFP Initiated Data Reset where the UFP is the VCONN Source" above. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and starts the VCONNDischargeTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 522 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests the DPM to turn off VCONN. 19 When the DPM indicates VCONN has been turned off the Policy Engine tells the Protocol Layer to form an PS_RDY Message. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 22 Protocol Layer stores the MessageID of the incoming Message. 23 The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and tells the DPM to perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 523 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.55 Steps for a DFP Initiated Data Reset where the UFP is the VCONN Source Step DFP (Reset Initiator) UFP/VCONN Source (Reset Responder) Page 524 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.5.4 DFP Receives Data Reset where the UFP is the VCONN Source This is an example of a Data Reset operation where the DFP receives a Data_Reset Message and the UFP is the VCONN Source. Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" shows the Messages as they flow across the bus and within the devices to accomplish the Data Reset. Figure 8.29 DFP Receives a Data Reset where the UFP is the VCONN Source : Protocol 1: Send Data_Reset : PHY : PHY : Protocol 2: Data_Reset 3: Data_Reset + CRC 4: Data_Reset Start CRCReceiveTimer 5: Data_Reset received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Data_Reset sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer Tell DPM to turn off VCONN. 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine Data_Reset Complete, USB Connection Established UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM that Data_Reset has been received Start VCONNDischargeTimer DPM indicates that VCONN has been turned off. 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Reset MessageIDCounter, stored MessageID and RetryCounter Reset MessageIDCounter, stored MessageID and RetryCounter Check and increment MessageIDCounter Stop CRCReceiveTimer Stop VCONNDischargeTimer Request DPM to perform a Data Reset 28: Send Data_Reset_Complete 29: Data_Reset_Complete 30: Data_Reset_Complete + CRC 31: Data_Reset_Complete 32: Data_Reset_Complete received Inform DPM Data Reset is complete 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: Data_Reset_Complete sent Start CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Inform DPM Data Reset Message sent Tell DPM indicates Data Reset process is complete Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 525 Table 8.56, "Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.29, "DFP Receives a Data Reset where the UFP is the VCONN Source" above. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) 1 The Policy Engine directs the Protocol Layer to generate a Data_Reset Message to request a Soft Reset. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Data_Reset Message. Starts CRCReceiveTimer. PHY Layer receives the Data_Reset Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Data_Reset Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset Message has been received. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. The Policy Engine stops the SenderResponseTimer and tells the DPM to turn off VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 526 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNDischargeTimer. 19 When the DPM indicates that VCONN has been turned off the Policy Engine directs the Protocol Layer to generate a PS_RDY Message to request a Soft Reset. 20 Protocol Layer creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the VCONNDischargeTimer and requests the DPM perform a Data Reset. The DPM proceeds to turn on VCONN and then reset the data connection. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. 28 The DPM indicates that the Data Reset process is complete. The Policy Engine directs the Protocol Layer to generate a Data_Reset_Complete Message. 29 Protocol Layer creates the Message and passes to PHY Layer. 30 PHY Layer receives the Data_Reset_Complete Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends CRC and sends the Data_Reset_Complete Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the Data_Reset_Complete Message to the Protocol Layer. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 527 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Data_Reset_Complete Message information to the Policy Engine that consumes it. The Policy Engine informs the DPM that a Data_Reset_Complete Message has been received. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC and checks the CRC to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Data_Reset_Complete Message was successfully sent. The Policy Engine informs the DPM that the Data_Reset_Complete Message was successfully sent. The reset is complete as defined in Section 6.3.14, "Data_Reset Message" Step 5. Port Partners re-establish a USB data connection. Table 8.56 Steps for a DFP Receiving a Data Reset where the UFP is the VCONN Source Step UFP/VCONN Source (Reset Initiator) DFP (Reset Responder) Page 528 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6 Hard Reset The following sections describe the steps required for a USB Power Delivery Hard Reset. The Hard Reset returns the operation of the USB Power Delivery to default Power Role/Data Role and operating voltage/current. During the Hard Reset USB Power Delivery PHY Layer communications Shall be disabled preventing communication between the Port Partner. Note: Hard Reset, in this case, is applied to the USB Power Delivery capability of an individual Port on which the Hard Reset is requested. A side effect of the Hard Reset is that it might reset other functions on the Port such as USB. 8.3.2.6.1 Source Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Source. Figure 8.30, "Source initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.30 Source initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink Hard Reset Complete Reset MessageIDCounter and RetryCounter Reset MessageIDCounter and RetryCounter 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN 9: Hard Reset Complete Channel enabled Channel enabled 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN Channel disabled Channel disabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 529 Table 8.57, "Steps for Source initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.30, "Source initiated Hard Reset" above. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter and RetryCounter. 5 The Protocol Layer informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation. and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Page 530 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.57 Steps for Source initiated Hard Reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 531 8.3.2.6.2 Sink Initiated Hard Reset This is an example of a Hard Reset operation when initiated by a Sink. Figure 8.31, "Sink Initiated Hard Reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.31 Sink Initiated Hard Reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 8: Power Supply Reset 6: Power Sink Reset 10: Send Capabilities 11: Capabilities 12: Capabilities + CRC 13: Capabilities Start CRCReceiveTimer Store copy of MessageID 14: Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18: Capabilities sent Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 7: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 9: Hard Reset Complete Channel enabled 2: Send Hard Reset 5: Hard Reset received Channel enabled Page 532 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.58, "Steps for Sink initiated Hard Reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.31, "Sink Initiated Hard Reset" above. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 6 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. 8 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 9 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 10 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 533 13 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 14 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.58 Steps for Sink initiated Hard Reset Step Source Sink Page 534 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.6.3 Source Initiated Hard Reset - Sink Long Reset This is an example of a Hard Reset operation when initiated by a Source. In this example the Sink is slow responding to the reset causing the Source to send multiple Source_Capabilities Messages before it receives a GoodCRC Message response. Figure 8.32, "Source initiated reset - Sink long reset" shows the Messages as they flow across the bus and within the devices to accomplish the Hard Reset. Figure 8.32 Source initiated reset - Sink long reset : Protocol : PHY : PHY : Protocol : Policy Engine : Policy Engine Source Sink 1: Send Hard Reset 2: Send Hard Reset 3: Hard Reset 4: Hard Reset received Hard Reset Complete Start NoResponseTimer Wait tPSHardReset Reset Power Supply Reset Port Data Role to DFP Turn off VCONN Reset MessageIDCounter, stored copy of MessageID and RetryCounter Reset MessageIDCounter, stored copy of MessageID and RetryCounter 5: Hard Reset received Reset Power Sink Reset Port Data Role to UFP Turn off VCONN 6: Power Supply Reset 11: Power Sink Reset 13: Send Capabilities 14: Capabilities 15: Capabilities + CRC 16: Capabilities Start CRCReceiveTimer Store copy of MessageID 17: Capabilities received 18: GoodCRC 19: GoodCRC + CRC 20: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 21: Capabilities sent Stop SourceCapabilitiesTimer Stop NoResponseTimer Start SenderResponseTimer Evaluate Capabilities 8: Send Capabilities 9: Capabilities 10: Capabilities + CRC Run SourceCapabilityTimer Send Capabilities messages until GoodCRC response is received. 12: Hard Reset Complete Power Sink Reset Power Supply Reset Turn on VCONN Channel disabled Channel disabled 7: Hard Reset Complete Channel enabled Channel enabled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 535 Table 8.59, "Steps for Source initiated Hard Reset - Sink long reset" below provides a detailed explanation of what happens at each labeled step in Figure 8.32, "Source initiated reset - Sink long reset" above. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink 1 The Policy Engine directs the Protocol Layer to generate Hard Reset Signaling. The Policy Engine starts the NoResponseTimer and requests the DPM to reset the power supply to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to DFP and to turn off VCONN if this is on. 2 Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. Protocol Layer requests the PHY Layer send Hard Reset Signaling. 3 PHY Layer sends the Hard Reset Signaling and then disables the PHY Layer communications channel for transmission and reception. PHY Layer receives the Hard Reset Signaling and disables the PHY Layer communications channel for transmission and reception. 4 PHY Layer informs the Protocol Layer of the Hard Reset. Protocol Layer resets MessageIDCounter, stored copy of MessageID and RetryCounter. 5 The Protocol Layer Informs the Policy Engine of the Hard Reset. The Policy Engine requests the DPM to reset the Power Sink to USB Default Operation. The Policy Engine requests the DPM to reset the Port Data Role to UFP and to turn off VCONN if this is on. 6 The power supply is reset to USB Default Operation and VCONN is turned on. The Policy Engine informs the Protocol Layer that the power supply has been reset. 7 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 8 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Policy Engine starts the SourceCapabilityTimer. The SourceCapabilityTimer times out one or more times until a GoodCRC Message response is received. 9 Protocol Layer creates the Message and passes to PHY Layer. 10 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. Note: Source_Capabilities Message not received since channel is disabled. 11 The Power Sink returns to USB Default Operation. The Policy Engine informs the Protocol Layer that the Power Sink has been reset. Page 536 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 12 The Protocol Layer informs the PHY Layer that the Hard Reset is complete. The PHY Layer enables the PHY Layer communications channel for transmission and reception. The reset is complete and protocol communication can restart. 13 Policy Engine directs the Protocol Layer to send a Source_Capabilities Message that represents the power supply’s present capabilities. Starts the SourceCapabilityTimer. 14 Protocol Layer creates the Message and passes to PHY Layer. 15 PHY Layer appends CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. PHY Layer receives the Source_Capabilities Message and checks the CRC to verify the Message. 16 PHY Layer removes the CRC and forwards the Source_Capabilities Message to the Protocol Layer. 17 Protocol Layer stores the MessageID of the incoming Message. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 18 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 19 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 20 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 21 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. Policy Engine stops the SourceCapabilityTimer, stops the NoResponseTimer and starts the SenderResponseTimer. USB Power Delivery communication is re-established. Table 8.59 Steps for Source initiated Hard Reset - Sink long reset Step Source Sink Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 537 8.3.2.7 Power Role Swap 8.3.2.7.1 Source Initiated Power Role Swap 8.3.2.7.1.1 Source Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap sequence. Page 538 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.33 Successful Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply stops sourcing power CC -> Rd 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC 36: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Tell Power Supply to stop sourcing power Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Sink to start sinking power Reset Protocol Layer New Power Roles Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 539 Table 8.60, "Steps for a Successful Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.33, "Successful Power Role Swap Sequence Initiated by the Source" above. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine requests its power supply to stop supplying power and stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 540 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the PSSourceOffTimer and tells the power supply to stop sinking current. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Message to Sink, creates the Message and passes to PHY Layer. 21 PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 541 30 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 35 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.60 Steps for a Successful Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Page 542 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.1.2 Source Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  An Reject Message in response to the PR_Swap Message. Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.34 Rejected Power Role Swap Sequence Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 543 Table 8.61, "Steps for a Rejected Source Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.34, "Rejected Power Role Swap Sequence Initiated by the Source" above. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 544 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.61 Steps for a Rejected Source Initiated Power Role Swap Sequence Step Initial Source Port Initially Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 545 8.3.2.7.1.3 Source Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, with a wait response, initiated by a Port which initially, at the start of this Message sequence, is acting as a Source and therefore has Rp pulled up on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" shows the Messages as they flow across the bus and within the devices. Figure 8.35 Power Role Swap Sequence with wait Initiated by the Source : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Source Port Initial Sink Port Stop SenderResponseTimer Tell Power Supply to stop sourcing power Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 546 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.62, "Steps for a Source Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.35, "Power Role Swap Sequence with wait Initiated by the Source" above. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Source and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 547 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.62 Steps for a Source Initiated Power Role Swap with Wait Sequence Step Initial Source Port Initially Sink Port Page 548 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2 Sink Initiated Power Role Swap 8.3.2.7.2.1 Sink Initiated Power Role Swap (Accept) This is an example of a successful Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are four distinct phases to the Power Role Swap:  A PR_Swap Message is sent.  An Accept Message in response to the PR_Swap Message.  The New Sink sets its power output to vSafe0V, then asserts Rd and sends a PS_RDY Message when this process is complete.  The New Source asserts Rp, then sets its power output to vSafe5V and sends a PS_RDY Message when it is ready to supply power. Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices to accomplish the Power Role Swap. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 549 Figure 8.36 Successful Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Tell Power Sink to stop sinking current Power Supply reaches 5V output Stop PSSourceOnTimer Tell Power Supply to start sinking power Reset Protocol Layer Tell Power Supply to stop sourcing power Power Supply stops sourcing power CC -> Rd Stop PSSourceOffTimer CC -> Rp Set Power Supply to 5V output New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 550 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.63, "Steps for a Successful Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.36, "Successful Power Role Swap Sequence Initiated by the Sink" above. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer and tells the power supply to stop sinking current. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 551 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine tells the power supply to stop supplying power. 19 The Policy Engine determines its power supply is no longer supplying VBUS. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer, directs the DPM to apply the Rp pull up and then starts switching the power supply to vSafe5V Source operation. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. 28 Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 552 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer, informs the power supply that it can start consuming power. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the PSSourceOnTimer, informs the power supply it can now sink power and resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Power Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.63 Steps for a Successful Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 553 8.3.2.7.2.2 Sink Initiated Power Role Swap (Reject) This is an example of a rejected Power Role Swap operation initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Reject Message in response to the PR_Swap Message. Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.37 Rejected Power Role Swap Sequence Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Page 554 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.64, "Steps for a Rejected Sink Initiated Power Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.37, "Rejected Power Role Swap Sequence Initiated by the Sink" above. Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is unable and unwilling to do the Power Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Reject Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 555 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.64 Steps for a Rejected Sink Initiated Power Role Swap Sequence Step Initial Sink Port Initial Source Port Page 556 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.7.2.3 Sink Initiated Power Role Swap (Wait) This is an example of a Power Role Swap operation, responded to with wait, initiated by a Port which initially, at the start of this Message sequence, is acting as a Sink and therefore has Rd pulled down on its CC wire. There are several phases to the Power Role Swap:  A PR_Swap Message is sent.  A Wait Message in response to the PR_Swap Message. Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" shows the Messages as they flow across the bus and within the devices. Figure 8.38 Power Role Swap Sequence with wait Initiated by the Sink : Protocol 1: Send PR_Swap : PHY : PHY : Protocol 2:PR_Swap 3: PR_Swap + CRC 4: PR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: PR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:PR_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate PR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port Stop SenderResponseTimer Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 557 Table 8.65, "Steps for a Sink Initiated Power Role Swap with Wait Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.38, "Power Role Swap Sequence with wait Initiated by the Sink" above. Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a PR_Swap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the PR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the PR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Wait Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 558 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Wait Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.65 Steps for a Sink Initiated Power Role Swap with Wait Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 559 8.3.2.8 Fast Role Swap This is an example of a successful Fast Role Swap operation initiated by a Port that is initially a Source and therefore has Rp pulled up on its CC wire and which has lost power and needs to get vSafe5V quickly. It does not include any subsequent Power Negotiation which is required in order to establish an Explicit Contract (see Section 8.3.2.2, "Power Negotiation"). There are several distinct phases to the Fast Role Swap Negotiation:  The Initial Source stops driving its power output which starts transitioning to vSafe0V and send the Fast Role Swap Request on the CC wire; these could occur in either order or simultaneously.  The Initial Sink stops sinking power. At this point the New Source still has Rd asserted and the New Sink still has Rp asserted.  An FR_Swap Message is sent by the New Source within tFRSwapInit of detecting the Fast Swap signal.  An Accept Message is sent by the New Sink in response to the FR_Swap Message.  The New Sink asserts Rd and sends a PS_RDY Message indicating that the voltage on VBUS is at or below vSafe5V.  The New Source asserts Rp and sends a PS_RDY Message indicating that it is acting as a Source and is sup- plying vSafe5V. Note: The New Source can start applying VBUS when VBUS is at or below vSafe5V (max) but will start driving VBUS to vSafe5V no later than tSrcFRSwap after detecting both the Fast Role Swap Request and that VBUS has dropped below vSafe5V (min). Figure 8.39, "Successful Fast Role Swap Sequence" shows the Messages as they flow across the bus and within the devices to accomplish the Fast Role Swap. Page 560 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.39 Successful Fast Role Swap Sequence : Protocol 1: Send FR_Swap : PHY : PHY : Protocol 2:FR_Swap 3: FR_Swap + CRC 4: FR_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: FR_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:FR_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer 28: Send PS_RDY 29: PS_RDY 30: PS_RDY + CRC 31: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 32: PS_RDY received 33: GoodCRC 34: GoodCRC + CRC 35: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 36: PS_RDY sent Evaluate FR_Swap request : Policy Engine : Policy Engine Initial Sink Port Initial Source Port 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer Start PSSourceOnTimer Port Power Role -> Source Port Power Role -> Sink Stop SenderResponseTimer Start PSSourceOffTimer Stop PSSourceOnTimer Reset Protocol Layer Power Supply acting as a Sink and VBUS at or below vSafe5V CC -> Rd vSafe5V is being sourced by the new Source Stop PSSourceOffTimer CC -> Rp New Power Roles Port Power Role = Sink CC = Rd Port Power Role = Source CC = Rp Tell Power Supply to Stop sourcing power and switch to Sink operation Signal Fast Swap on the CC Wire Fast Role Swap signal detected on CC Wire Tell Power Supply to stop sinking current. Fast Swap signal (CC driven to Gnd through rFRSwapTx or rFRSwapCableTx) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 561 Table 8.66, "Steps for a Successful Fast Role Swap Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.39, "Successful Fast Role Swap Sequence" above. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. The DPM detects Fast Swap on the CC wire and tells the power supply to stop sinking current. The Policy Engine directs the Protocol Layer to send an FR_Swap Message within tFRSwapInit of detecting the Fast Swap signal. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. The DPM tells the Power Supply to stop sourcing power and switch to Sink operation. The DPM signals Fast Swap on the CC wire by driving CC to ground with a resistance of less than rFRSwapTx for at least tFRSwapTx. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the FR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the FR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the PR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received FR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the FR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the PR_Swap Message sent by the Sink and decides that it is able and willing to do the Power Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Accept Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PR_Swap Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer, starts the PSSourceOffTimer. Page 562 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. 19 The Policy Engine determines its power supply is no longer supplying VBUS and is acting as a Sink. The Policy Engine requests the DPM to assert the Rd pull down on the CC wire. The Policy Engine then directs the Protocol Layer to generate a PS_RDY Message, with the Port Power Role Messageset to Sink, to tell its Port Partner that it can begin to source VBUS. 20 Protocol Layer sets the Port Power Role Messageto Sink, creates the Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOffTimer. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. Policy Engine starts PSSourceOnTimer. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 563 28 The Policy Engine directs the DPM to apply the Rp pull up. Note: At some point (either before or after receiving the PS_RDY Message) the New Source has ap- plied vSafe5V no later than tSrcFRSwap after detecting the Fast Role Swap Request and that VBUS has dropped below vSafe5V. Policy Engine, when its power supply is ready to supply power, tells the Protocol Layer to form a PS_RDY Message. The Port Power Role Messageis set to Source. 29 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 30 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 31 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 32 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. The Policy Engine stops the PSSourceOnTimer. 33 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 34 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine resets the Protocol Layer. 35 PHY Layer removes the CRC and forwards the GoodCRC to the Protocol Layer. 36 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Policy Engine resets the CapsCounter, resets the Protocol Layer and starts the SwapSourceStartTimer which must timeout before sending any Source_Capabilities Messages. The Fast Role Swap is complete, the Power Roles have been reversed and the Port Partners are free to Negotiate for more power. Table 8.66 Steps for a Successful Fast Role Swap Sequence Step Initial Sink Port Initial Source Port Page 564 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9 Data Role Swap 8.3.2.9.1 Data Role Swap, Initiated by UFP Operating as Sink 8.3.2.9.1.1 Data Role Swap, Initiated by UFP Operating as Sink (Accept) Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.40 Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 565 Table 8.67, "Steps for Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.40, "Data Role Swap, UFP operating as Sink initiates" above. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 566 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.67 Steps for Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 567 8.3.2.9.1.2 Data Role Swap, Initiated by UFP Operating as Sink (Reject) Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.41 Rejected Data Role Swap, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Page 568 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.68, "Steps for Rejected Data Role Swap, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.41, "Rejected Data Role Swap, UFP operating as Sink initiates" above. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 569 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.68 Steps for Rejected Data Role Swap, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Page 570 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.1.3 Data Role Swap, Initiated by UFP Operating as Sink (Wait) Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP (Host) and a Source (Rp asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.42 Data Role Swap with Wait, UFP operating as Sink initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rd (Sink) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role -> DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 571 Table 8.69, "Steps for Data Role Swap with Wait, UFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.42, "Data Role Swap with Wait, UFP operating as Sink initiates" above. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 572 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.69 Steps for Data Role Swap with Wait, UFP operating as Sink initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 573 8.3.2.9.2 Data Role Swap, Initiated by UFP Operating as Source 8.3.2.9.2.1 Data Role Swap, Initiated by UFP Operating as Source (Accept) Figure 8.43, "Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.43 Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> UFP (Device) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 574 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.70, "Steps for Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.43, "Data Role Swap, UFP operating as Source initiates" above. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 575 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 The Policy Engine requests that Data Role is changed from UFP (Device) to DFP (Host). The Power Delivery Data Role is now a DFP (Host), and Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to UFP (Device), with Port Data Role set to UFP and still operating as a Sink (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.70 Steps for Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 576 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.2.2 Data Role Swap, Initiated by UFP Operating as Source (Reject) Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.44 Rejected Data Role Swap, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 577 Table 8.71, "Steps for Rejected Data Role Swap, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.44, "Rejected Data Role Swap, UFP operating as Source initiates" above. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 578 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.71 Steps for Rejected Data Role Swap, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 579 8.3.2.9.2.3 Data Role Swap, Initiated by UFP Operating as Source (Wait) Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the UFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.45 Data Role Swap with Wait, UFP operating as Source initiates : Protocol 1: Send Dr_Swap : PHY : PHY : Protocol 2:Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Dr_Swap sent Start SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role = DFP (Host) : Policy Engine : Policy Engine Initial UFP Source Port Initially DFP Sink Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> DFP (Host) CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Page 580 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.72, "Steps for Data Role Swap with Wait, UFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.45, "Data Role Swap with Wait, UFP operating as Source initiates" above. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and checks the CRC to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 581 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.72 Steps for Data Role Swap with Wait, UFP operating as Source initiates Step Initial UFP Source Port Initial DFP Sink Port Page 582 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3 Data Role Swap, Initiated by DFP Operating as Source 8.3.2.9.3.1 Data Role Swap, Initiated by DFP Operating as Source (Accept) Figure 8.46, "Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.46 Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer New Host/Device Roles CC = Rd (Sink) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 583 Table 8.73, "Steps for Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.46, "Data Role Swap, DFP operating as Source initiates" above. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 584 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP, still operating as a Sink (Rd asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP and continues supplying power as a Source (Rp asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.73 Steps for Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 585 8.3.2.9.3.2 Data Role Swap, Initiated by DFP Operating as Source (Reject) Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.47 Rejected Data Role Swap, DFP operating as Source initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Page 586 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.74, "Steps for Rejected Data Role Swap, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.47, "Rejected Data Role Swap, DFP operating as Source initiates" above. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 587 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.74 Steps for Rejected Data Role Swap, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Page 588 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.3.3 Data Role Swap, Initiated by DFP Operating as Source (Wait) Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Sink (Rd asserted), and a Port which is initially a DFP and a Source (Rp asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed by wait. Figure 8.48 Data Role Swap with Wait, DFP operating as Source initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Sink Port Initial DFP Source Port Stop SenderResponseTimer CC = Rd (Sink) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rd (Sink) Port Data Role =UFP (Device) Start SenderResponseTimer CC = Rp (Source) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role = UFP (Device) CC = Rp (Source) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 589 Table 8.75, "Steps for Data Role Swap with Wait, DFP operating as Source initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.48, "Data Role Swap with Wait, DFP operating as Source initiates" above. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port 1 Port starts as a UFP (Device) operating as a Sink with Rd asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as Source with Rp asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Page 590 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.75 Steps for Data Role Swap with Wait, DFP operating as Source initiates Step Initial UFP Sink Port Initial DFP Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 591 8.3.2.9.4 Data Role Swap, Initiated by DFP Operating as Sink 8.3.2.9.4.1 Data Role Swap, Initiated by DFP Operating as Sink (Accept) Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) but exchange Data Roles between DFP (Host) and UFP (Device). Figure 8.49 Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Accept : PHY : PHY : Protocol 11:Accept 12: Accept + CRC 13: Accept Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Accept sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer New Host/Device Roles CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> DFP (Host) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> UFP (Device) Page 592 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.76, "Steps for Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.49, "Data Role Swap, DFP operating as Sink initiates" above. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Accept Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. PHY Layer receives the Accept Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 593 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine requests that the Data Role is changed to DFP (Host), with Port Data Role set to DFP and continues supplying power as a Source (Rp asserted). The Policy Engine requests that Data Role is changed from DFP (Host) to UFP (Device). The Power Delivery Data Role is now a UFP (Device), with Port Data Role set to UFP, still operating as a Sink (Rd asserted). The Data Role Swap is complete; the Data Roles have been reversed while maintaining the direction of power flow. Table 8.76 Steps for Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 594 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.9.4.2 Data Role Swap, Initiated by DFP Operating as Sink (Reject) Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is rejected. Figure 8.50 Rejected Data Role Swap, DFP operating as Sink initiates : Protocol 10: Send Reject : PHY : PHY : Protocol 11:Reject 12: Reject + CRC 13: Reject Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Reject sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 595 Table 8.77, "Steps for Rejected Data Role Swap, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.50, "Rejected Data Role Swap, DFP operating as Sink initiates" above. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is unable and unwilling to do the Data Role Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Reject Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. PHY Layer receives the Reject Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 596 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.77 Steps for Rejected Data Role Swap, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 597 8.3.2.9.4.3 Data Role Swap, Initiated by DFP Operating as Sink (Wait) Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" shows an example sequence between a Port, which is initially a UFP (Device) and a Source (Rp asserted), and a Port which is initially a DFP (Host) and a Sink (Rd asserted). A Data Role Swap is initiated by the DFP. During the process the Port Partners maintain their operation as either a Source or a Sink (power and Rp/Rd remain constant) and the exchange of Data Roles is delayed with a wait. Figure 8.51 Data Role Swap with Wait, DFP operating as Sink initiates : Protocol 10: Send Wait : PHY : PHY : Protocol 11:Wait 12: Wait + CRC 13: Wait Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 18:Wait sent : Policy Engine : Policy Engine Initial UFP Source Port Initial DFP Sink Port Stop SenderResponseTimer CC = Rp (Source) Port Data Role = UFP (Device) CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rp (Source) Port Data Role -> UFP (Device) 1: Send Dr_Swap 2: Dr_Swap 3: Dr_Swap + CRC 4: Dr_Swap Check MessageID against local copy Store copy of MessageID 5: Dr_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Dr_Swap sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate Dr_Swap request CC = Rp (Source) Port Data Role = UFP (Device) Start SenderResponseTimer CC = Rd (Sink) Port Data Role = DFP (Host) CC = Rd (Sink) Port Data Role -> DFP (Host) Page 598 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.78, "Steps for Data Role Swap with Wait, DFP operating as Sink initiates" below provides a detailed explanation of what happens at each labeled step in Figure 8.51, "Data Role Swap with Wait, DFP operating as Sink initiates" above. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port 1 Port starts as a UFP (Device) operating as Source with Rp asserted and Port Data Role set to UFP. Port starts as a DFP (Host) operating as a Sink with Rd asserted and Port Data Role set to DFP. The Policy Engine directs the Protocol Layer to send a DR_Swap Message. 2 Protocol Layer creates the DR_Swap Message and passes to PHY Layer. 3 PHY Layer receives the DR_Swap Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the DR_Swap Message. Starts CRCReceiveTimer. 4 PHY Layer removes the CRC and forwards the DR_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received DR_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends CRC and sends the GoodCRC Message. PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the DR_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the DR_Swap Message and decides that it is able and willing to do the Data Role Swapbut not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Wait Message and passes to PHY Layer. 12 PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. PHY Layer receives the Wait Message and checks the CRC to verify the Message. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 599 16 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.78 Steps for Data Role Swap with Wait, DFP operating as Sink initiates Step Initial UFP Source Port Initial DFP Sink Port Page 600 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10 VCONN Swap 8.3.2.10.1 VCONN Source Swap, initiated by VCONN Source 8.3.2.10.1.1 VCONN Source Swap, initiated by VCONN Source (Accept) Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source role. Figure 8.52 Successful VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Vconn is on 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC 27: PS_RDY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Stop SenderResponseTimer Start VCONNOnTimer Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN has been swapped VCONN off VCONN Source Tell power supply to start supplying VCONN VCONN is off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 601 Table 8.79, "Steps for Source to Sink VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.52, "Successful VCONN Source Swap, initiated by VCONN Source" above. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 602 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine asks the DPM to turn on VCONN. 19 The DPM informs the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Source it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 VCONN is off. Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. The Port Partners have swapped VCONN Source role. Table 8.79 Steps for Source to Sink VCONN Source Swap Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 603 8.3.2.10.1.2 VCONN Source Swap, initiated by VCONN Source (Reject) Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.53 Rejected VCONN Source Swap, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Page 604 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.80, "Steps for Rejected VCONN Source Swap" below provides a detailed explanation of what happens at each labeled step in Figure 8.53, "Rejected VCONN Source Swap, initiated by VCONN Source" above. Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 605 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent Table 8.80 Steps for Rejected VCONN Source Swap Step Initially VCONN Source Initially VCONN off Page 606 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.1.3 VCONN Source Swap, initiated by VCONN Source (Wait) Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" shows an example sequence where the VCONN Source and tells its Port Partner to supply VCONN and is told to wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source role. Figure 8.54 VCONN Source Swap with Wait, initiated by VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN Source Port Initially VCONN off Stop SenderResponseTimer VCONN off VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 607 Table 8.81, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.54, "VCONN Source Swap with Wait, initiated by VCONN Source" above. Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off 1 The VCONN Source’s Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. VCONN is off. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer and starts the VCONNOnTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 608 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent Table 8.81 Steps for VCONN Source Swap with Wait Step Initially VCONN Source Initially VCONN off Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 609 8.3.2.10.2 VCONN Source Swap, initiated by non-VCONN Source 8.3.2.10.2.1 VCONN Source Swap, initiated by non-VCONN Source (Accept) Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) but exchange the VCONN Source. Figure 8.55 VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept Check MessageID against local copy Store copy of MessageID 14: Accept received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port Vconn is on Start VCONNOnTimer VCONN Source VCONN Off Stop SenderResponseTimer Tell power supply to start supplying VCONN 19: Send PS_RDY 20: PS_RDY 21: PS_RDY + CRC 22: PS_RDY Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: PS_RDY received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: PS_RDY sent Source is supplying VCONN Stop VCONNOnTimer Tell power supply to turn off VCONN VCONN is off Page 610 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.82, "Steps for VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.55, "VCONN Source Swap, initiated by non-VCONN Source" above. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap. It tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Accept Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Accept Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 611 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. The Policy Engine starts the VCONNOnTimer. 19 The DPM tells the Policy Engine that its power supply is supplying VCONN. The Policy Engine directs the Protocol Layer to generate a PS_RDY Message to tell the Sink it can turn off VCONN. 20 Protocol Layer creates the PS_RDY Message and passes to PHY Layer. 21 PHY Layer appends a CRC and sends the PS_RDY Message. Starts CRCReceiveTimer. PHY Layer receives the PS_RDY Message and compares the CRC it calculated with the one sent to verify the Message. 22 PHY Layer removes the CRC and forwards the PS_RDY Message to the Protocol Layer. 23 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PS_RDY Message information to the Policy Engine that consumes it. 24 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 25 PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the GoodCRC Message. The Policy Engine stops the VCONNOnTimer, and tells the power supply to stop sourcing VCONN. 26 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 27 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PS_RDY Message was successfully sent. VCONN is off. The Port Partners have swapped VCONN Source role. Table 8.82 Steps for VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Page 612 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.10.2.2 VCONN Source Swap, initiated by non-VCONN Source (Reject) Figure 8.56, "Rejected VCONN Source Swap, initiated by non-VCONN Source" shows an example where the Port which is not initially supplying VCONN and requests a VCONN Swap which is rejected. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.56 Rejected VCONN Source Swap, initiated by non-VCONN Source : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject Check MessageID against local copy Store copy of MessageID 14: Reject received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 613 Table 8.83, "Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.56, "Rejected VCONN Source Swap, initiated by non- VCONN Source" above. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is unable and unwilling to do the VCONN Swap. It tells the Protocol Layer to form a Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Reject Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Reject Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 614 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Table 8.83 Steps for Rejected VCONN Source Swap, Initiated by non-VCONN Source Step Initially VCONN off Initially VCONN Source Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 615 8.3.2.10.2.3 VCONN Source Swap (Wait) Figure 8.57, "VCONN Source Swap with Wait" shows an example where the Port requests a VCONN Swap which is delayed with a wait. During the process the Port Partners, keep their Power Role as Source or Sink, maintain their operation as either a Source or a Sink (power remains constant) and don't exchange the VCONN Source. Figure 8.57 VCONN Source Swap with Wait : Protocol 1: Send VCONN_Swap : PHY : PHY : Protocol 2:VCONN_Swap 3: VCONN_Swap + CRC 4: VCONN_Swap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: VCONN_Swap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:VCONN_Swap sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait Check MessageID against local copy Store copy of MessageID 14: Wait received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Evaluate VCONN_Swap request : Policy Engine : Policy Engine Initially VCONN off Initially VCONN Source Port VCONN Source VCONN Off Stop SenderResponseTimer Page 616 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.84, "Steps for VCONN Source Swap with Wait" below provides a detailed explanation of what happens at each labeled step in Figure 8.57, "VCONN Source Swap with Wait" above. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source 1 The Source starts with VCONN off. The Policy Engine directs the Protocol Layer to send a VCONN_Swap Message. The Sink starts as the VCONN Source. 2 Protocol Layer creates the VCONN_Swap Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the VCONN_Swap Message. Starts CRCReceiveTimer. PHY Layer receives the VCONN_Swap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the VCONN_Swap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received VCONN_Swap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the VCONN_Swap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine evaluates the VCONN_Swap Message sent by the Source and decides that it is able and willing to do the VCONN Swap but not at this time. It tells the Protocol Layer to form a Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Wait Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Wait Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. The Policy Engine tells the DPM to turn on VCONN. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 617 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Table 8.84 Steps for VCONN Source Swap with Wait Step Initially VCONN off Initially VCONN Source Page 618 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11 Additional Capabilities, Status and Information 8.3.2.11.1 Alert 8.3.2.11.1.1 Source sends Alert to a Sink Figure 8.58, "Source Alert to Sink" shows an example sequence between a Source and a Sink where the Source alerts the Sink that there has been a status change. This AMS will be followed by getting the Source status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.58 Source Alert to Sink : Sink Policy Engine : Protocol : PHY : PHY : Protocol : Source Policy Engine Sink Port Source Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 619 Table 8.85, "Steps for Source Alert to Sink" below provides a detailed explanation of what happens at each labeled step in Figure 8.58, "Source Alert to Sink" above. Table 8.85 Steps for Source Alert to Sink Step Sink Source 1 The DPM indicates a Source alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 620 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.1.2 Sink sends Alert to a Source Figure 8.59, "Sink Alert to Source" shows an example sequence between a Source and a Sink where the Sink alerts the Source that there has been a status change. This AMS will be followed by getting the Sink status to determine further details of the alert (see Section 8.3.2.11.2, "Status"). Figure 8.59 Sink Alert to Source : Source Policy Engine : Protocol : PHY : PHY : Protocol : Sink Policy Engine Source Port Sink Port 1: Send Alert 2: Alert 3: Alert + CRC 4: Alert Check MessageID against local copy Store copy of MessageID 5: Alert received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Alert sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 621 Table 8.86, "Steps for Sink Alert to Source" below provides a detailed explanation of what happens at each labeled step in Figure 8.59, "Sink Alert to Source" above. Table 8.86 Steps for Sink Alert to Source Step Source Sink 1 The DPM indicates a Sink alert condition. The Policy Engine tells the Protocol Layer to form an Alert Message. 2 Protocol Layer creates the Alert Message and passes to PHY Layer. 3 PHY Layer receives the Alert Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Alert Message. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Alert Message to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Alert Message was successfully sent. Page 622 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2 Status 8.3.2.11.2.1 Sink Gets Source Status Figure 8.60, "Sink Gets Source Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Sink gets more details on the change. Figure 8.60 Sink Gets Source Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 623 Table 8.87, "Steps for a Sink getting Source Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.60, "Sink Gets Source Status" above. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 624 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Source has informed the Sink of its present status. Table 8.87 Steps for a Sink getting Source Status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 625 8.3.2.11.2.2 Source Gets Sink Status Figure 8.61, "Source Gets Sink Status" shows an example sequence between a Source and a Sink where, after the Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the Source gets more details on the change. Figure 8.61 Source Gets Sink Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink Status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Status sent Page 626 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.88, "Steps for a Source getting Sink Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.61, "Source Gets Sink Status" above. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Status Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 627 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Sink has informed the Source of its present status. Table 8.88 Steps for a Source getting Sink Status Sequence Step Source Port Sink Port Page 628 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.2.3 VCONN Source Gets Cable Plug Status Figure 8.62, "VCONN Source Gets Cable Plug Status" shows an example sequence between a VCONN Source and a Cable Plug where, after the VCONN Source has received an alert (see Section 8.3.2.11.2, "Status") that there has been a status change, the VCONN Source gets more details on the change. Figure 8.62 VCONN Source Gets Cable Plug Status : Protocol 1: Send Get_Status : PHY : PHY : Protocol 2:Get_Status 3: Get_Status + CRC 4: Get_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Status sent Start SenderResponseTimer 10: Send Status 11: Status 12: Status + CRC 13: Status Check MessageID against local copy Store copy of MessageID 14: Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Status Information from DPM : Policy Engine : Policy Engine VCONN Source Port Cable Plug Stop SenderResponseTimer 18: Status sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 629 Table 8.89, "Steps for a VCONN Source getting Cable Plug Status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.62, "VCONN Source Gets Cable Plug Status" above. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug 1 Policy Engine directs the Protocol Layer to send a Get_Status Message. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Status Message. PHY Layer appends a CRC and sends the Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 630 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Status Message was successfully sent. The Cable Plug has informed the VCONN Source of its present status. Table 8.89 Steps for a VCONN Source getting Cable Plug Status Sequence Step VCONN Source Port Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 631 8.3.2.11.2.4 Sink Gets Source PPS Status Figure 8.63, "Sink Gets Source PPS Status" shows an example sequence between a Source and a Sink where, after the Sink has received an alert (see Section 8.3.2.11.2, "Status") that there has been a PPS status change, the Sink gets more details on the change. Figure 8.63 Sink Gets Source PPS Status : Protocol 1: Send Get_PPS_Status : PHY : PHY : Protocol 2:Get_PPS_Status 3: Get_PPS_Status + CRC 4: Get_PPS_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_PPS_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_PPS_Status sent Start SenderResponseTimer 10: Send PPS_Status 11: PPS_Status 12: PPS_Status + CRC 13: PPS_Status Check MessageID against local copy Store copy of MessageID 14: PPS_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source PPS Status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: PPS_Status sent Page 632 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.90, "Steps for a Sink getting Source PPS status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.63, "Sink Gets Source PPS Status" above. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_PPS_Status Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_PPS_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_PPS_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_PPS_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_PPS_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source status which is provided. The Policy Engine tells the Protocol Layer to form a PPS_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the PPS_Status Message. PHY Layer appends a CRC and sends the PPS_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received PPS_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 633 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the PPS_Status Message was successfully sent. The Source has informed the Sink of its present PPS status. Table 8.90 Steps for a Sink getting Source PPS status Sequence Step Sink Port Source Port Page 634 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3 Source/Sink Capabilities 8.3.2.11.3.1 SPR 8.3.2.11.3.1.1 Sink Gets Source Capabilities Figure 8.64, "Sink Gets Source's Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source Capabilities. Figure 8.64 Sink Gets Source's Capabilities : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd 18: Source_Capabilities sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 635 Table 8.91, "Steps for a Sink getting Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.64, "Sink Gets Source's Capabilities" above. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 636 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its capabilities. Table 8.91 Steps for a Sink getting Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 637 8.3.2.11.3.1.2 Dual-Role Source Gets Source Capabilities from a Dual-Role Sink Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as a Source. Figure 8.65 Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source : Protocol 1: Send Get_Source_Cap : PHY : PHY : Protocol 2:Get_Source_Cap 3: Get_Source_Cap + CRC 4: Get_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap sent Start SenderResponseTimer 10: Send Source_Capabilities 11: Source_Capabilities 12: Source_Capabilities + CRC 13: Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 638 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.92, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.65, "Dual-Role Source Gets Dual-Role Sink's Capabilities as a Source" above. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities Message. PHY Layer appends a CRC and sends the Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 639 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its capabilities. Table 8.92 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 640 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.1.3 Source Gets Sink Capabilities Figure 8.66, "Source Gets Sink's Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink Capabilities. Figure 8.66 Source Gets Sink's Capabilities : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 641 Table 8.93, "Steps for a Source getting Sink Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.66, "Source Gets Sink's Capabilities" above. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 642 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its capabilities. Table 8.93 Steps for a Source getting Sink Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 643 8.3.2.11.3.1.4 Dual-Role Sink Get Sink Capabilities from a Dual-Role Source Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.67 Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink : Protocol 1: Send Get_Sink_Cap : PHY : PHY : Protocol 2:Get_Sink_Cap 3: Get_Sink_Cap + CRC 4: Get_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap sent Start SenderResponseTimer 10: Send Sink_Capabilities 11: Sink_Capabilities 12: Sink_Capabilities + CRC 13: Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 644 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.94, "Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.67, "Dual-Role Sink Gets Dual-Role Source's Capabilities as a Sink" above. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities Message. PHY Layer appends a CRC and sends the Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 645 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as a Sink. Table 8.94 Steps for a Dual-Role Sink getting Dual-Role Source capabilities as a Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 646 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2 EPR 8.3.2.11.3.2.1 Sink Gets EPR Source Capabilities Figure 8.68, "Sink Gets Source's EPR Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's EPR Capabilities. Figure 8.68 Sink Gets Source's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 647 Table 8.95, "Steps for a Sink getting EPR Source Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.68, "Sink Gets Source's EPR Capabilities" above. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present EPR Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 648 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities Message was successfully sent. The Source has informed the Sink of its EPR Capabilities. Table 8.95 Steps for a Sink getting EPR Source Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 649 8.3.2.11.3.2.2 Dual-Role Source Gets Source Capabilities from a Dual-Role EPR Sink Figure 8.69, "Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink Capabilities as an EPR Source. Figure 8.69 Dual-Role Source Gets Dual-Role Sink's Capabilities as an EPR Source : Protocol 1: Send EPR_Get_EPR_Source_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Source_Cap 3: EPR_Get_EPR_Source_Cap + CRC 4: EPR_Get_EPR_Source_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Source_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Source_Cap sent Start SenderResponseTimer 10: Send EPR_Source_Capabilities 11: EPR_Source_Capabilities 12: EPR_Source_Capabilities + CRC 13: EPR_Source_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Source_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: EPR_Source_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 650 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.96, "Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.69, "Dual-Role Source Gets Dual- Role Sink's Capabilities as an EPR Source" above. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Source_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Source_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Source_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Source_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Source_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Source_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Source_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Source_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Source_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Source_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 651 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Source_Capabilities Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its EPR Capabilities. Table 8.96 Steps for a Dual-Role Source getting Dual-Role Sink's capabilities as an EPR Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 652 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.3.2.3 Source Gets Sink EPR Capabilities Figure 8.70, "Source Gets Sink's EPR Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's EPR Capabilities. Figure 8.70 Source Gets Sink's EPR Capabilities : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 653 Table 8.97, "Steps for a Source getting Sink EPR Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.70, "Source Gets Sink's EPR Capabilities" above. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 654 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Sink has informed the Source of its EPR Capabilities. Table 8.97 Steps for a Source getting Sink EPR Capabilities Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 655 8.3.2.11.3.2.4 Dual-Role Sink Get Sink EPR Capabilities from a Dual-Role Source Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Dual-Role Power Sink gets the Dual-Role Power Source Capabilities as a Sink. Figure 8.71 Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink : Protocol 1: Send EPR_Get_EPR_Sink_Cap : PHY : PHY : Protocol 2:EPR_Get_EPR_Sink_Cap 3: EPR_Get_EPR_Sink_Cap + CRC 4: EPR_Get_EPR_Sink_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: EPR_Get_EPR_Sink_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:EPR_Get_EPR_Sink_Cap sent Start SenderResponseTimer 10: Send EPR_Sink_Capabilities 11: EPR_Sink_Capabilities 12: EPR_Sink_Capabilities + CRC 13: EPR_Sink_Capabilities Check MessageID against local copy Store copy of MessageID 14: EPR_Sink_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get EPR Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: EPR_Sink_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 656 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.98, "Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.71, "Dual-Role Sink Gets Dual-Role Source's Capabilities as an EPR Sink" above. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port 1 The Port has Port Power Role set to Dual-Role Power Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a EPR_Get_Sink_Cap Message. The Port has Port Power Role set to Dual-Role Power Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the EPR_Get_Sink_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the EPR_Get_Sink_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the EPR_Get_Sink_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Get_Sink_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Get_Sink_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Dual- Role Power Source Capabilities which are provided. The Policy Engine tells the Protocol Layer to form an EPR_Sink_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the EPR_Sink_Capabilities Message. PHY Layer appends a CRC and sends the EPR_Sink_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received EPR_Sink_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 657 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the EPR_Sink_Capabilities Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Capabilities as an EPR Sink. Table 8.98 Steps for a Dual-Role Sink getting Dual-Role Source Capabilities as an EPR Sink Sequence Step Dual-Role Sink Port Dual-Role Source Port Page 658 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4 Extended Capabilities 8.3.2.11.4.1 Sink Gets Source Extended Capabilities Figure 8.72, "Sink Gets Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Extended Capabilities. Figure 8.72 Sink Gets Source's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 659 Table 8.99, "Steps for a Sink getting Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.72, "Sink Gets Source's Extended Capabilities" above. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 660 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Source has informed the Sink of its Extended Capabilities. Table 8.99 Steps for a Sink getting Source Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 661 8.3.2.11.4.2 Dual-Role Source Gets Source Capabilities Extended from a Dual- Role Sink Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Source gets the Dual-Role Power Sink's Extended Capabilities as a Source. Figure 8.73 Dual-Role Source Gets Dual-Role Sink's Extended Capabilities : Protocol 1: Send Get_Source_Cap_Extended : PHY : PHY : Protocol 2:Get_Source_Cap_Extended 3: Get_Source_Cap_Extended + CRC 4: Get_Source_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Cap_Extended sent Start SenderResponseTimer 10: Send Source_Capabilities_Extended 11: Source_Capabilities_Extended 12: Source_Capabilities_Extended + CRC 13: Source_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Source_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 662 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.100, "Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.73, "Dual-Role Source Gets Dual-Role Sink's Extended Capabilities" above. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Source which are provided. The Policy Engine tells the Protocol Layer to form a Source_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Source_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 663 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Capabilities_Extended Message was successfully sent. The Dual-Role Power Sink has informed the Dual-Role Power Source of its Extended Capabilities as a Source. Table 8.100 Steps for a Dual-Role Source getting Dual-Role Sink Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 664 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.4.3 Source Gets Sink Extended Capabilities Figure 8.74, "Source Gets Sink's Extended Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Extended Capabilities. Figure 8.74 Source Gets Sink's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 665 Table 8.101, "Steps for a Source getting Sink Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.74, "Source Gets Sink's Extended Capabilities" above. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Sink Extended Capabilities which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 666 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Sink has informed the Source of its Extended Capabilities. Table 8.101 Steps for a Source getting Sink Extended Capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 667 8.3.2.11.4.4 Dual-Role Sink Gets Sink Capabilities Extended from a Dual-Role Source Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" shows an example sequence between a Source and a Sink when the Dual-Role Power Sink gets the Dual-Role Power Source's Extended Capabilities as a Sink. Figure 8.75 Dual-Role Sink Gets Dual-Role Source's Extended Capabilities : Protocol 1: Send Get_Sink_Cap_Extended : PHY : PHY : Protocol 2:Get_Sink_Cap_Extended 3: Get_Sink_Cap_Extended + CRC 4: Get_Sink_Cap_Extended Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Sink_Cap_Extended received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Sink_Cap_Extended sent Start SenderResponseTimer 10: Send Sink_Capabilities_Extended 11: Sink_Capabilities_Extended 12: Sink_Capabilities_Extended + CRC 13: Sink_Capabilities_Extended Check MessageID against local copy Store copy of MessageID 14: Sink_Capabilities_Extended received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get extended Sink capability Information from DPM : Policy Engine : Policy Engine Dual-Role Sink Port Dual-Role Source Port Stop SenderResponseTimer 18: Sink_Capabilities_Extended sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 668 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.102, "Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.75, "Dual-Role Sink Gets Dual-Role Source's Extended Capabilities" above. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Sink_Cap_Extended Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Sink_Cap_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Sink_Cap_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Sink_Cap_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Sink_Cap_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Sink_Cap_Extended Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Extended Capabilities as a Sink which are provided. The Policy Engine tells the Protocol Layer to form a Sink_Capabilities_Extended Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Sink_Capabilities_Extended Message. PHY Layer appends a CRC and sends the Sink_Capabilities_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Sink_Capabilities_Extended Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 669 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Sink_Capabilities_Extended Message was successfully sent. The Dual-Role Power Source has informed the Dual-Role Power Sink of its Extended Capabilities as a Sink. Table 8.102 Steps for a Dual-Role Sink getting Dual-Role Source Extended Capabilities Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 670 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5 Battery Capabilities and Status 8.3.2.11.5.1 Sink Gets Battery Capabilities Figure 8.76, "Sink Gets Source's Battery Capabilities" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery capabilities for a given Battery. Figure 8.76 Sink Gets Source's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 671 Table 8.103, "Steps for a Sink getting Source Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.76, "Sink Gets Source's Battery Capabilities" above. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 672 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Source has informed the Sink of the Battery capabilities for the requested Battery. Table 8.103 Steps for a Sink getting Source Battery capabilities Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 673 8.3.2.11.5.2 Source Gets Battery Capabilities Figure 8.77, "Source Gets Sink's Battery Capabilities" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery capabilities for a given Battery. Figure 8.77 Source Gets Sink's Battery Capabilities : Protocol 1: Send Get_Battery_Cap : PHY : PHY : Protocol 2:Get_Battery_Cap 3: Get_Battery_Cap + CRC 4: Get_Battery_Cap Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Cap received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Cap sent Start SenderResponseTimer 10: Send Battery_Capabilities 11: Battery_Capabilities 12: Battery_Capabilities + CRC 13: Battery_Capabilities Check MessageID against local copy Store copy of MessageID 14: Battery_Capabilities received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery capability Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Capabilities sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 674 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.104, "Steps for a Source getting Sink Battery capabilities Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.77, "Source Gets Sink's Battery Capabilities" above. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Cap Message containing the number of the Battery for which capabilities are being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Cap Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Cap Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Cap Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Cap Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Cap Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery capabilities, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Capabilities Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Capabilities Message. PHY Layer appends a CRC and sends the Battery_Capabilities Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Capabilities Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 675 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Capabilities Message was successfully sent. The Sink has informed the Source of the Battery capabilities for the requested Battery. Table 8.104 Steps for a Source getting Sink Battery capabilities Sequence Step Source Port Sink Port Page 676 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.5.3 Sink Gets Battery Status Figure 8.78, "Sink Gets Source's Battery Status" shows an example sequence between a Source and a Sink when the Sink gets the Source's Battery status for a given Battery. Figure 8.78 Sink Gets Source's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 677 Table 8.105, "Steps for a Sink getting Source Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.78, "Sink Gets Source's Battery Status" above. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 678 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Source has informed the Sink of the Battery status for the requested Battery. Table 8.105 Steps for a Sink getting Source Battery status Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 679 8.3.2.11.5.4 Source Gets Battery Status Figure 8.79, "Source Gets Sink's Battery Status" shows an example sequence between a Source and a Sink when the Source gets the Sink's Battery status for a given Battery. Figure 8.79 Source Gets Sink's Battery Status : Protocol 1: Send Get_Battery_Status : PHY : PHY : Protocol 2:Get_Battery_Status 3: Get_Battery_Status + CRC 4: Get_Battery_Status Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Battery_Status received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Battery_Status sent Start SenderResponseTimer 10: Send Battery_Status 11: Battery_Status 12: Battery_Status + CRC 13: Battery_Status Check MessageID against local copy Store copy of MessageID 14: Battery_Status received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Battery status Information from DPM : Policy Engine : Policy Engine Source Port Sink Port Stop SenderResponseTimer 18: Battery_Status sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 680 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.106, "Steps for a Source getting Sink Battery status Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.79, "Source Gets Sink's Battery Status" above. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Battery_Status Message containing the number of the Battery for which status is being requested. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Battery_Status Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Battery_Status Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Battery_Status Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Battery_Status Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Battery_Status Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source Battery status, for the requested Battery number, which are provided. The Policy Engine tells the Protocol Layer to form a Battery_Status Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Battery_Status Message. PHY Layer appends a CRC and sends the Battery_Status Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Battery_Status Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 681 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Battery_Status Message was successfully sent. The Sink has informed the Source of the Battery status for the requested Battery. Table 8.106 Steps for a Source getting Sink Battery status Sequence Step Source Port Sink Port Page 682 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6 Manufacturer Information 8.3.2.11.6.1 Source Gets Port Manufacturer Information from a Sink Figure 8.80, "Source Gets Sink's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.80 Source Gets Sink's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 683 Table 8.107, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.80, "Source Gets Sink's Port Manufacturer Information" above. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 684 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.107 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 685 8.3.2.11.6.2 Sink Gets Port Manufacturer Information from a Source Figure 8.81, "Sink Gets Source's Port Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.81 Sink Gets Source's Port Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 686 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.108, "Steps for a Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.81, "Sink Gets Source's Port Manufacturer Information" above. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 687 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the Port. Table 8.108 Steps for a Source getting Sink's Port Manufacturer Information Sequence Step Sink Port Source Port Page 688 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.3 Source Gets Battery Manufacturer Information from a Sink Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for one of its Batteries. Figure 8.82 Source Gets Sink's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 689 Table 8.109, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.82, "Source Gets Sink's Battery Manufacturer Information" above. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Page 690 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.109 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 691 8.3.2.11.6.4 Sink Gets Battery Manufacturer Information from a Source Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Manufacturer information for the Port. Figure 8.83 Sink Gets Source's Battery Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 692 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.110, "Steps for a Source getting Sink's Battery Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.83, "Sink Gets Source's Battery Manufacturer Information" above. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Battery information for a given Battery. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Battery’s manufacturer information for a given Battery which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 693 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Sink has informed the Source of the manufacturer information for the requested Battery. Table 8.110 Steps for a Source getting Sink's Battery Manufacturer Information Sequence Step Sink Port Source Port Page 694 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.6.5 VCONN Source Gets Manufacturer Information from a Cable Plug Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Manufacturer information. Figure 8.84 VCONN Source Gets Cable Plug's Manufacturer Information : Protocol 1: Send Get_Manufacturer_Info : PHY : PHY : Protocol 2:Get_Manufacturer_Info 3: Get_Manufacturer_Info + CRC 4: Get_Manufacturer_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Manufacturer_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Manufacturer_Info sent Start SenderResponseTimer 10: Send Manufacturer_Info 11: Manufacturer_Info 12: Manufacturer_Info + CRC 13: Manufacturer_Info Check MessageID against local copy Store copy of MessageID 14: Manufacturer_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Manufacturer Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Manufacturer_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 695 Table 8.111, "Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.84, "VCONN Source Gets Cable Plug's Manufacturer Information" above. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Manufacturer_Info Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Manufacturer_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Manufacturer_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Manufacturer_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Manufacturer_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Manufacturer_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Manufacturer_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Manufacturer_Info Message. PHY Layer appends a CRC and sends the Manufacturer_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Manufacturer_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 696 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Manufacturer_Info Message was successfully sent. The Cable Plug has informed the Source of its manufacturer information. Table 8.111 Steps for a VCONN Source getting Sink's Port Manufacturer Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 697 8.3.2.11.7 Country Codes 8.3.2.11.7.1 8.3.2.12.7.1Source Gets Country Codes from a Sink Figure 8.85, "Source Gets Sink's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's Country Codes. Figure 8.85 Source Gets Sink's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 698 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.112, "Steps for a Source getting Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.85, "Source Gets Sink's Country Codes" above. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 699 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.112 Steps for a Source getting Country Codes Sequence Step Source Port Sink Port Page 700 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.7.2 Sink Gets Country Codes from a Source Figure 8.86, "Sink Gets Source's Country Codes" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.86 Sink Gets Source's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Codes sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 701 Table 8.113, "Steps for a Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.86, "Sink Gets Source's Country Codes" above. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 702 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Sink has informed the Source of the country codes. Table 8.113 Steps for a Source getting Sink's Country Codes Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 703 8.3.2.11.7.3 VCONN Source Gets Country Codes from a Cable Plug Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Country Codes. Figure 8.87 VCONN Source Gets Cable Plug's Country Codes : Protocol 1: Send Get_Country_Codes : PHY : PHY : Protocol 2:Get_Country_Codes 3: Get_Country_Codes + CRC 4: Get_Country_Codes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Codes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Codes sent Start SenderResponseTimer 10: Send Country_Codes 11: Country_Codes 12: Country_Codes + CRC 13: Country_Codes Check MessageID against local copy Store copy of MessageID 14: Country_Codes received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country codes from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Codes sent Page 704 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.114, "Steps for a VCONN Source getting Sink's Country Codes Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.87, "VCONN Source Gets Cable Plug's Country Codes" above. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Codes Message with a request for Port information. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Codes Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Codes Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Codes Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Codes Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Codes Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Codes Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Codes Message. PHY Layer appends a CRC and sends the Country_Codes Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Codes Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 705 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Codes Message was successfully sent. The Cable Plug has informed the Source of its country codes. Table 8.114 Steps for a VCONN Source getting Sink's Country Codes Sequence Step VCONN Source Cable Plug Page 706 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8 Country Information 8.3.2.11.8.1 Source Gets Country Information from a Sink Figure 8.88, "Source Gets Sink's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country information. Figure 8.88 Source Gets Sink's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 707 Table 8.115, "Steps for a Source getting Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.88, "Source Gets Sink's Country Information" above. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific Country Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 708 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.115 Steps for a Source getting Country Information Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 709 8.3.2.11.8.2 Sink Gets Country Information from a Source Figure 8.89, "Sink Gets Source's Country Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's country codes. Figure 8.89 Sink Gets Source's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 710 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.116, "Steps for a Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.89, "Sink Gets Source's Country Information" above. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 711 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Sink has informed the Source of the country information. Table 8.116 Steps for a Source getting Sink's Country Information Sequence Step Sink Port Source Port Page 712 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.8.3 VCONN Source Gets Country Information from a Cable Plug Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's country information. Figure 8.90 VCONN Source Gets Cable Plug's Country Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 713 Table 8.117, "Steps for a VCONN Source getting Sink's Country Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.90, "VCONN Source Gets Cable Plug's Country Information" above. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Country_Info Message with a request for Port information for a specific country code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Country_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Country_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Country_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Country_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Country_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Country_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Country_Info Message. PHY Layer appends a CRC and sends the Country_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Country_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 714 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Country_Info Message was successfully sent. The Cable Plug has informed the Source of its country information. Table 8.117 Steps for a VCONN Source getting Sink's Country Information Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 715 8.3.2.11.9 Revision Information 8.3.2.11.9.1 Source Gets Revision Information from a Sink Figure 8.91, "Source Gets Sink's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision information. Figure 8.91 Source Gets Sink's Revision Information : Protocol 1: Send Get_Revision : PHY : PHY : Protocol 2:Get_Revision 3: Get_Revision + CRC 4: Get_Revision Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Revision received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Revision sent Start SenderResponseTimer 10: Send Revision 11: Revision 12: Revision + CRC 13: Revision Check MessageID against local copy Store copy of MessageID 14: Revision received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Revision sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 716 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.118, "Steps for a Source getting Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.91, "Source Gets Sink's Revision Information" above. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision Code. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 717 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.118 Steps for a Source getting Revision Information Sequence Step Source Port Sink Port Page 718 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.9.2 Sink Gets Revision Information from a Source Figure 8.92, "Sink Gets Source's Revision Information" shows an example sequence between a Source and a Sink when the Source gets the Sink's Revision codes. Figure 8.92 Sink Gets Source's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get country information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Country_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 719 Table 8.119, "Steps for a Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.92, "Sink Gets Source's Revision Information" above. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Port’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision_Info Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 720 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Sink has informed the Source of the Revision information. Table 8.119 Steps for a Source getting Sink's Revision Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 721 8.3.2.11.9.3 VCONN Source Gets Revision Information from a Cable Plug Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" shows an example sequence between a VCONN Source (Source or Sink) and a Cable Plug when the VCONN Source gets the Cable Plug's Revision information. Figure 8.93 VCONN Source Gets Cable Plug's Revision Information : Protocol 1: Send Get_Country_Info : PHY : PHY : Protocol 2:Get_Country_Info 3: Get_Country_Info + CRC 4: Get_Country_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Country_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Country_Info sent Start SenderResponseTimer 10: Send Country_Info 11: Country_Info 12: Country_Info + CRC 13: Country_Info Check MessageID against local copy Store copy of MessageID 14: Country_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Country Information from DPM : Policy Engine : Policy Engine Cable Plug VCONN Source Port Stop SenderResponseTimer 18: Country_Info sent Page 722 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.120, "Steps for a VCONN Source getting Sink's Revision Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.93, "VCONN Source Gets Cable Plug's Revision Information" above. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug 1 The Port is currently acting as the VCONN Source. Policy Engine directs the Protocol Layer to send a Get_Revision Message with a request for Port information for a specific Revision code. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Revision Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Revision Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Revision Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Revision Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Revision Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the Cable Plug’s manufacturer information which is provided. The Policy Engine tells the Protocol Layer to form a Revision Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Revision Message. PHY Layer appends a CRC and sends the Revision Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Revision Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 723 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Revision Message was successfully sent. The Cable Plug has informed the Source of its Revision information. Table 8.120 Steps for a VCONN Source getting Sink's Revision Information Sequence Step VCONN Source Cable Plug Page 724 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.11.10 Source Information 8.3.2.11.10.1 Sink Gets Source Information Figure 8.94, "Sink Gets Source's Information" shows an example sequence between a Source and a Sink when the Sink gets the Source's information. Figure 8.94 Sink Gets Source's Information : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Sink Port Source Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 725 Table 8.121, "Steps for a Sink getting Source Information Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.94, "Sink Gets Source's Information" above. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 726 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Source has provided the Sink with its information. Table 8.121 Steps for a Sink getting Source Information Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 727 8.3.2.11.10.2 Dual-Role Source Gets Source Information from a Dual-Role Sink Figure 8.95, "Dual-Role Source Gets Dual-Role Sink's Information as a Source" shows an example sequence between a Dual-Role Power Source and a Dual-Role Power Sink when the Source gets the Sink's Information as a Source. Figure 8.95 Dual-Role Source Gets Dual-Role Sink's Information as a Source : Protocol 1: Send Get_Source_Info : PHY : PHY : Protocol 2:Get_Source_Info 3: Get_Source_Info + CRC 4: Get_Source_Info Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Get_Source_Info received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Get_Source_Info sent Start SenderResponseTimer 10: Send Source_Info 11: Source_Info 12: Source_Info + CRC 13: Source_Info Check MessageID against local copy Store copy of MessageID 14: Source_Info received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get Source capability Information from DPM : Policy Engine : Policy Engine Dual-Role Source Port Dual-Role Sink Port Stop SenderResponseTimer 18: Source_Info sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 728 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.122, "Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.95, "Dual-Role Source Gets Dual- Role Sink's Information as a Source" above. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Get_Source_Info Message. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Get_Source_Info Message. Starts CRCReceiveTimer. PHY Layer receives the Get_Source_Info Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Get_Source_Info Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Get_Source_Info Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Get_Source_Info Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine requests the DPM for the present Source information which is provided. The Policy Engine tells the Protocol Layer to form a Source_Info Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Source_Info Message. PHY Layer appends a CRC and sends the Source_Info Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Source_Info Message information to the Policy Engine that consumes it. 14 The Policy Engine stops the SenderResponseTimer. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 729 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Source_Info Message was successfully sent. The Dual-Role Power Sink has provided the Dual-Role Power Source with its information. Table 8.122 Steps for a Dual-Role Source getting Dual-Role Sink's Information as a Source Sequence Step Dual-Role Source Port Dual-Role Sink Port Page 730 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12 Security 8.3.2.12.1 Source requests security exchange with Sink Figure 8.96, "Source requests security exchange with Sink" shows an example sequence for a security exchange between a Source and a Sink. Figure 8.96 Source requests security exchange with Sink : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 731 Table 8.123, "Steps for a Source requesting a security exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.96, "Source requests security exchange with Sink" above. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 732 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.123 Steps for a Source requesting a security exchange with a Sink Sequence Step Source Port Sink Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 733 8.3.2.12.2 Sink requests security exchange with Source Figure 8.97, "Sink requests security exchange with Source" shows an example sequence for a security exchange between a Sink and a Source. Figure 8.97 Sink requests security exchange with Source : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Security_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 734 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.124, "Steps for a Sink requesting a security exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.97, "Sink requests security exchange with Source" above. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 735 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.124 Steps for a Sink requesting a security exchange with a Source Sequence Step Sink Port Source Port Page 736 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.12.3 VCONN Source requests security exchange with Cable Plug Figure 8.98, "VCONN Source requests security exchange with Cable Plug" shows an example sequence for a security exchange between a VCONN Source and a Cable Plug. Figure 8.98 VCONN Source requests security exchange with Cable Plug : Protocol 1: Send Security_Request : PHY : PHY : Protocol 2:Security_Request 3: Security_Request + CRC 4: Security_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Security_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Security_Request sent 10: Send Security_Response 11: Security_Response 12: Security_Response + CRC 13: Security_Response Check MessageID against local copy Store copy of MessageID 14: Security_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get security response from DPM : Policy Engine : Policy Engine Vconn Source Cable Plug 18: Security_Response sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 737 Table 8.125, "Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.98, "VCONN Source requests security exchange with Cable Plug" above. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Security_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Security_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Security_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Security_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the security request which is provided. The Policy Engine tells the Protocol Layer to form a Security_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Security_Response Message. PHY Layer appends a CRC and sends the Security_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Security_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 738 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Security_Response Message was successfully sent. The security exchange is complete. Table 8.125 Steps for a VCONN Source requesting a security exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 739 8.3.2.13 Firmware Update 8.3.2.13.1 Source requests firmware update exchange with Sink Figure 8.99, "Source requests firmware update exchange with Sink" shows an example sequence for a firmware update exchange between a Source and a Sink. Figure 8.99 Source requests firmware update exchange with Sink : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Source Port Sink Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Page 740 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.126, "Steps for a Source requesting a firmware update exchange with a Sink Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.99, "Source requests firmware update exchange with Sink" above. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port 1 The Port has Port Power Role set to Source and the Rp pull up on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 741 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.126 Steps for a Source requesting a firmware update exchange with a Sink Sequence Step Source Port Sink Port Page 742 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.13.2 Sink requests firmware update exchange with Source Figure 8.100, "Sink requests firmware update exchange with Source" shows an example sequence for a firmware update exchange between a Sink and a Source. Figure 8.100 Sink requests firmware update exchange with Source : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine Sink Port Source Port 18: Firmware_Update_Response sent Port Power Role = Source CC = Rp Port Power Role = Sink CC = Rd Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 743 Table 8.127, "Steps for a Sink requesting a firmware update exchange with a Source Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.100, "Sink requests firmware update exchange with Source" above. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port 1 The Port has Port Power Role set to Sink with the Rd pull down on its CC wire. Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. The Port has Port Power Role set to Source and the Rp pull up on its CC wire. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. Page 744 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.127 Steps for a Sink requesting a firmware update exchange with a Source Sequence Step Sink Port Source Port Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 745 8.3.2.13.3 VCONN Source requests firmware update exchange with Cable Plug Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" shows an example sequence for a firmware update exchange between a VCONN Source and a Cable Plug. Figure 8.101 VCONN Source requests firmware update exchange with Cable Plug : Protocol 1: Send Firmware_Update_Request : PHY : PHY : Protocol 2:Firmware_Update_Request 3: Firmware_Update_Request + CRC 4: Firmware_Update_Request Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Firmware_Update_Request received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9:Firmware_Update_Request sent 10: Send Firmware_Update_Response 11: Firmware_Update_Response 12: Firmware_Update_Response + CRC 13: Firmware_Update_Response Check MessageID against local copy Store copy of MessageID 14: Firmware_Update_Response received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Get firmware update response from DPM : Policy Engine : Policy Engine VCONN Source Cable Plug 18: Firmware_Update_Response sent Page 746 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.128, "Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.101, "VCONN Source requests firmware update exchange with Cable Plug" above. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug 1 Policy Engine directs the Protocol Layer to send a Firmware_Update_Request Message using a Payload supplied by the DPM. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Firmware_Update_Request Message. Starts CRCReceiveTimer. PHY Layer receives the Firmware_Update_Request Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Firmware_Update_Request Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Request Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Request Message was successfully sent. 10 Policy Engine requests the DPM for the response to the firmware update request which is provided. The Policy Engine tells the Protocol Layer to form a Firmware_Update_Response Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Firmware_Update_Response Message. PHY Layer appends a CRC and sends the Firmware_Update_Response Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Firmware_Update_Response Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 747 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Firmware_Update_Response Message was successfully sent. The firmware update exchange is complete. Table 8.128 Steps for a VCONN Source requesting a firmware update exchange with a Cable Plug Sequence Step VCONN Source Cable Plug Page 748 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14 Structured VDM 8.3.2.14.1 Discover Identity 8.3.2.14.1.1 Initiator to Responder Discover Identity (ACK) Figure 8.102, "Initiator to Responder Discover Identity (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers identity information from the Responder. Figure 8.102 Initiator to Responder Discover Identity (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity ACK 11: Discover Identity ACK 12: Discover Identity ACK + CRC 13: Discover Identity ACK Check MessageID against local copy Store copy of MessageID 14: Discover Identity ACK received Stop VDMResponseTimer DPM evaluates Identity information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 749 Table 8.129, "Steps for Initiator to UFP Discover Identity (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.102, "Initiator to Responder Discover Identity (ACK)" above. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command ACK response. 11 Protocol Layer creates the Discover Identity Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 750 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command ACK response was successfully sent. Table 8.129 Steps for Initiator to UFP Discover Identity (ACK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 751 8.3.2.14.1.2 Initiator to Responder Discover Identity (NAK) Figure 8.103, "Initiator to Responder Discover Identity (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a NAK. Figure 8.103 Initiator to Responder Discover Identity (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity NAK 11: Discover Identity NAK 12: Discover Identity NAK + CRC 13: Discover Identity NAK Check MessageID against local copy Store copy of MessageID 14: Discover Identity NAK received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Page 752 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.130, "Steps for Initiator to UFP Discover Identity (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.103, "Initiator to Responder Discover Identity (NAK)" above. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command NAK response. 11 Protocol Layer creates the Discover Identity Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 753 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.130 Steps for Initiator to UFP Discover Identity (NAK) Step Initiator Responder Page 754 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.1.3 Initiator to Responder Discover Identity (BUSY) Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover identity information from the Responder but receives a BUSY. Figure 8.104 Initiator to Responder Discover Identity (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover Identity 2: Discover Identity 3: Discover Identity + CRC 4: Discover Identity Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover Identity received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover Identity sent Start VDMResponseTimer 10: Send Discover Identity BUSY 11: Discover Identity BUSY 12: Discover Identity BUSY + CRC 13: Discover Identity BUSY Check MessageID against local copy Store copy of MessageID 14: Discover Identity BUSY received Stop VDMResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover Identity BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Identity information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 755 Table 8.131, "Steps for Initiator to UFP Discover Identity (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.104, "Initiator to Responder Discover Identity (BUSY)" above. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Identity Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover Identity Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Identity Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Identity Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Identity Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Identity Command BUSY response. 11 Protocol Layer creates the Discover Identity Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover Identity Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Identity Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Identity Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 756 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Identity Command NAK response was successfully sent. Table 8.131 Steps for Initiator to UFP Discover Identity (BUSY) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 757 8.3.2.14.2 Discover SVIDs 8.3.2.14.2.1 Initiator to Responder Discover SVIDs (ACK) Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers SVID information from the Responder. Figure 8.105 Initiator to Responder Discover SVIDs (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs ACK 11: Discover_SVIDs ACK 12: Discover_SVIDs ACK + CRC 13: Discover_SVIDs ACK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs ACK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 758 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.132, "Steps for DFP to UFP Discover SVIDs (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.105, "Initiator to Responder Discover SVIDs (ACK)" above. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command ACK response. 11 Protocol Layer creates the Discover SVIDs Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 759 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command ACK response was successfully sent. Table 8.132 Steps for DFP to UFP Discover SVIDs (ACK) Step Initiator Responder Page 760 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.2.2 Initiator to Responder Discover SVIDs (NAK) Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a NAK. Figure 8.106 Initiator to Responder Discover SVIDs (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs NAK 11: Discover_SVIDs NAK 12: Discover_SVIDs NAK + CRC 13: Discover_SVIDs NAK Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs NAK received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 761 Table 8.133, "Steps for DFP to UFP Discover SVIDs (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.106, "Initiator to Responder Discover SVIDs (NAK)" above. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command NAK response. 11 Protocol Layer creates the Discover SVIDs Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 762 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command NAK response was successfully sent. Table 8.133 Steps for DFP to UFP Discover SVIDs (NAK) Step Initiator Responder Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 763 8.3.2.14.2.3 Initiator to Responder Discover SVIDs (BUSY) Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover SVID information from the Responder but receives a BUSY. Figure 8.107 Initiator to Responder Discover SVIDs (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_SVIDs 2: Discover_SVIDs 3: Discover_SVIDs + CRC 4: Discover_SVIDs Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_SVIDs received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_SVIDs sent Start VDMResponseTimer 10: Send Discover_SVIDs BUSY 11: Discover_SVIDs BUSY 12: Discover_SVIDs BUSY + CRC 13: Discover_SVIDs BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_SVIDs BUSY received Stop VDMResponseTimer DPM evaluates SVIDs information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_SVIDs BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request SVIDs from Device Policy Manager Page 764 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.134, "Steps for DFP to UFP Discover SVIDs (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.107, "Initiator to Responder Discover SVIDs (BUSY)" above. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder 1 The Initiator has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover SVIDs Command request. The Responder has an Explicit Contract. 2 Protocol Layer creates the Discover SVIDs Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover SVIDs Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover SVIDs Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover SVIDs Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover SVIDs Command BUSY response. 11 Protocol Layer creates the Discover SVIDs Command BUSY response and passes to PHY Layer. 12 PHY Layer receives the Discover SVIDs Command BUSY response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover SVIDs Command BUSY response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover SVIDs Command BUSY response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 765 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover SVIDs Command BUSY response was successfully sent. Table 8.134 Steps for DFP to UFP Discover SVIDs (BUSY) Step Initiator Responder Page 766 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3 Discover Modes 8.3.2.14.3.1 Initiator to Responder Discover Modes (ACK) Figure 8.108, "Initiator to Responder Discover Modes (ACK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator discovers Mode information from the Responder. Figure 8.108 Initiator to Responder Discover Modes (ACK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes ACK 11: Discover_Modes ACK 12: Discover_Modes ACK + CRC 13: Discover_Modes ACK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes ACK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 767 Table 8.135, "Steps for DFP to UFP Discover Modes (ACK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.108, "Initiator to Responder Discover Modes (ACK)". Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command ACK response. 11 Protocol Layer creates the Discover Modes Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 768 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command ACK response was successfully sent. Table 8.135 Steps for DFP to UFP Discover Modes (ACK) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 769 8.3.2.14.3.2 Initiator to Responder Discover Modes (NAK) Figure 8.109, "Initiator to Responder Discover Modes (NAK)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a NAK. Figure 8.109 Initiator to Responder Discover Modes (NAK) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes NAK 11: Discover_Modes NAK 12: Discover_Modes NAK + CRC 13: Discover_Modes NAK Check MessageID against local copy Store copy of MessageID 14: Discover_Modes NAK received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes NAK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Page 770 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.136, "Steps for DFP to UFP Discover Modes (NAK)" below provides a detailed explanation of what happens at each labeled step in Figure 8.109, "Initiator to Responder Discover Modes (NAK)". Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 771 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.136 Steps for DFP to UFP Discover Modes (NAK) Step DFP UFP Page 772 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.3.3 Initiator to Responder Discover Modes (BUSY) Figure 8.110, "Initiator to Responder Discover Modes (BUSY)" shows an example sequence between an Initiator and Responder, where both Port Partners are in an Explicit Contract and the Initiator attempts to discover Mode information from the Responder but receives a BUSY. Figure 8.110 Initiator to Responder Discover Modes (BUSY) : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Initiator Responder 1: Send Discover_Modes 2: Discover_Modes 3: Discover_Modes + CRC 4: Discover_Modes Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Discover_Modes received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Discover_Modes sent Start VDMResponseTimer 10: Send Discover_Modes BUSY 11: Discover_Modes BUSY 12: Discover_Modes BUSY + CRC 13: Discover_Modes BUSY Check MessageID against local copy Store copy of MessageID 14: Discover_Modes BUSY received Stop VDMResponseTimer DPM evaluates Modes information 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Discover_Modes BUSY sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Explicit PD Contract Explicit PD Contract Request Modes information from Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 773 Table 8.137, "Steps for DFP to UFP Discover Modes (BUSY)" below provides a detailed explanation of what happens at each labeled step in Figure 8.110, "Initiator to Responder Discover Modes (BUSY)". Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP 1 The DFP has an Explicit Contract. The Policy Engine directs the Protocol Layer to send a Discover Modes Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Discover Modes Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Discover Modes Command request. Starts CRCReceiveTimer. PHY Layer receives the Discover Modes Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Discover Modes Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command request was successfully sent. Policy Engine starts the VDMResponseTimer. 10 Policy Engine requests the identity information from the DPM. The Policy Engine tells the Protocol Layer to form a Discover Modes Command NAK response. 11 Protocol Layer creates the Discover Modes Command NAK response and passes to PHY Layer. 12 PHY Layer receives the Discover Modes Command NAK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Discover Modes Command NAK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Discover Modes Command NAK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMResponseTimer and passed the Identity information to the DPM for evaluation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 774 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Discover Modes Command NAK response was successfully sent. Table 8.137 Steps for DFP to UFP Discover Modes (BUSY) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 775 8.3.2.14.4 Enter/Exit Mode 8.3.2.14.4.1 DFP to UFP Enter Mode Figure 8.111, "DFP to UFP Enter Mode" shows an example sequence between a DFP and a UFP that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.111 DFP to UFP Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP Supported SVIDS/Modes discovered Enter USB Safe State 37: Send Enter Mode 38: Enter Mode 39: Enter Mode + CRC 40: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 41: Enter Mode received 42: GoodCRC 43: GoodCRC + CRC 44: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 45: Enter Mode sent Start VDMModeEntryTimer 46: Send Enter Mode ACK 47: Enter Mode ACK 48: Enter Mode ACK + CRC 49: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 50: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 51: GoodCRC 52: GoodCRC + CRC 53: GoodCRC 54: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Operation USB Operation Evaluate Enter Mode request Enter New Mode New Mode Entered Page 776 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.138, "Steps for DFP to UFP Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.111, "DFP to UFP Enter Mode" above. Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. The Policy Engine directs the Protocol Layer to send an Enter Mode Command request. The UFP has an Explicit Contract. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. The Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 777 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and UFP are operating in the new Mode Table 8.138 Steps for DFP to UFP Enter Mode Step DFP UFP Page 778 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.2 DFP to UFP Exit Mode Figure 8.112, "DFP to UFP Exit Mode" shows an example sequence between a DFP and a UFP, where the DFP commands the UFP to exit the only Active Mode. Figure 8.112 DFP to UFP Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : UFP Policy Engine DFP UFP 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 779 Table 8.139, "Steps for DFP to UFP Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.112, "DFP to UFP Exit Mode" above. Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The UFP is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. The Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Page 780 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and UFP are in USB Operation Table 8.139 Steps for DFP to UFP Exit Mode Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 781 8.3.2.14.4.3 DFP to Cable Plug Enter Mode Figure 8.113, "DFP to Cable Plug Enter Mode" shows an example sequence between a DFP and a Cable Plug that occurs after the DFP has discovered supported SVIDs and Modes at which point it selects and enters a Mode. Figure 8.113 DFP to Cable Plug Enter Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug Supported SVIDs/Modes Discovered Enter USB Safe Mode Wait tCableMessage before transmission 19: Send Enter Mode 20: Enter Mode 21: Enter Mode + CRC 22: Enter Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 23: Enter Mode received 24: GoodCRC 25: GoodCRC + CRC 26: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 27: Enter Mode sent Start VDMModeEntryTimer 10: Send Enter Mode ACK 11: Enter Mode ACK 12: Enter Mode ACK + CRC 13: Enter Mode ACK Check MessageID against local copy Store copy of MessageID 14: Enter Mode ACK received Stop VDMModeEntryTimer Enter New Mode 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Enter Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer USB Mode USB Mode Evaluate Enter Mode request Enter New Mode Wait tCableMessage before transmission New Mode Entered Page 782 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.140, "Steps for DFP to Cable Plug Enter Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.113, "DFP to Cable Plug Enter Mode" above. Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug 1 The DFP has an Explicit Contract The DFP has discovered the supported SVIDS using the Discover SVIDs Command request and the supported Modes using the Discover Modes Command request The DFP goes to USB Safe State. The DPM requests the Policy Engine to enter a Mode. tCableMessage after the last GoodCRC Message was sent the Policy Engine directs the Protocol Layer to send an Enter Mode Command request. 2 Protocol Layer creates the Enter Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Enter Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command request was successfully sent. Policy Engine starts the VDMModeEntryTimer. 10 Policy Engine requests the DPM to enter the new Mode. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Enter Mode Command ACK response. 11 Protocol Layer creates the Enter Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Enter Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Enter Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter Mode Command ACK response information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 783 14 The Policy Engine stops the VDMModeEntryTimer and requests the DPM to enter the new Mode. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter Mode Command ACK response was successfully sent. DFP and Cable Plug are operating in the new Mode Table 8.140 Steps for DFP to Cable Plug Enter Mode Step DFP Cable Plug Page 784 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.14.4.4 DFP to Cable Plug Exit Mode Figure 8.114, "DFP to Cable Plug Exit Mode" shows an example sequence between a USB Type-C® DFP and a Cable Plug, where the DFP commands the Cable Plug to exit an Active Mode. Figure 8.114 DFP to Cable Plug Exit Mode : DFP Policy Engine : Protocol : PHY : PHY : Protocol : Cable Plug Policy Engine DFP Cable Plug 1: Send Exit Mode 2: Exit Mode 3: Exit Mode + CRC 4: Exit Mode Start CRCReceiveTimer Check MessageID against local copy Store copy of MessageID 5: Exit Mode received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC Check and increment MessageIDCounter Stop CRCReceiveTimer 9: Exit Mode sent Start VDMModeExitTimer 10: Send Exit Mode ACK 11: Exit Mode ACK 12: Exit Mode ACK + CRC 13: Exit Mode ACK Check MessageID against local copy Store copy of MessageID 14: Exit Mode ACK received Stop VDMModeExitTimer Enter USB Operation 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Exit Mode ACK sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer In Mode In Mode Enter USB Safe State Evaluate Exit Mode request Enter USB Operation Wait tCableMessage before transmission USB operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 785 Table 8.141, "Steps for DFP to Cable Plug Exit Mode" below provides a detailed explanation of what happens at each labeled step in Figure 8.114, "DFP to Cable Plug Exit Mode" above. Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug 1 The DFP is in a Mode and then enters USB Safe State. The Policy Engine directs the Protocol Layer to send an Exit Mode Command request. The Cable Plug is in a Mode. 2 Protocol Layer creates the Exit Mode Command request and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Exit Mode Command request. Starts CRCReceiveTimer. PHY Layer receives the Exit Mode Command request and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Exit Mode Command request to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command request information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command request was successfully sent. Policy Engine starts the VDMModeExitTimer. 10 Policy Engine requests the DPM to enter USB operation. tCableMessage after the GoodCRC Message was sent the Policy Engine tells the Protocol Layer to form an Exit Mode Command ACK response. 11 Protocol Layer creates the Exit Mode Command ACK response and passes to PHY Layer. 12 PHY Layer receives the Exit Mode Command ACK response and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Exit Mode Command ACK response. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Exit Mode Command ACK response information to the Policy Engine that consumes it. 14 The Policy Engine stops the VDMModeExitTimer and requests the DPM to enter USB Operation. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 786 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Exit Mode Command ACK response was successfully sent. Both DFP and Cable Plug are in USB Operation Table 8.141 Steps for DFP to Cable Plug Exit Mode Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 787 8.3.2.14.4.5 Initiator to Responder Attention Figure 8.115, "Initiator to Responder Attention" shows an example sequence between an Initiator and a Responder, where the Initiator requests attention from the Responder. Figure 8.115 Initiator to Responder Attention : Policy Engine : Protocol : PHY : PHY : Protocol : Policy Engine Responder Initiator 1: Send Attention 2: Attention 3: Attention + CRC 4: Attention Check MessageID against local copy Store copy of MessageID 5: Attention received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Attention sent Start CRCReceiveTimer Check and increment MessageIDCounter Stop CRCReceiveTimer Page 788 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.142, "Steps for Initiator to Responder Attention" below provides a detailed explanation of what happens at each labeled step in Figure 8.115, "Initiator to Responder Attention" above. Table 8.142 Steps for Initiator to Responder Attention Step Responder Initiator 1 The DPM requests attention. The Policy Engine tells the Protocol Layer to form an Attention Command request. 2 Protocol Layer creates the Attention Command request and passes to PHY Layer. 3 PHY Layer receives the Attention Command request and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Attention Command request. Starts CRCReceiveTimer. 4 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Attention Command request information to the Policy Engine that consumes it. 5 The Policy Engine informs the DPM 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Attention Command request was successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 789 8.3.2.15 Built in Self-Test (BIST) 8.3.2.15.1 BIST Carrier Mode The following is an example of a BIST Carrier Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.116, "BIST Carrier Mode Test" shows the Messages as they flow across the bus and within the devices. This test enables the measurement of power supply noise and frequency drift. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Carrier Mode BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT starts sending the Test Pattern. 5) Operator does the measurements. 6) The test ends after tBISTContMode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.1, "BIST Carrier Mode". Figure 8.116 BIST Carrier Mode Test : Protocol 1: Send BIST(Carrier Mode) : PHY : PHY : Protocol 2: BIST(Carrier Mode) 3: BIST(Carrier Mode) + CRC 4: BIST(Carrier Mode) Start CRCReceiveTimer 5: BIST(Carrier Mode) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Carrier Mode) sent : Policy Engine : Policy Engine Go to BIST Carrier Mode Tester UUT 12: Send Test Pattern 13: Send Test Pattern 14: Test Pattern Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (after tBISTContMode) Enter BIST Carrier Mode mode 10: Go to BIST Carrier Mode 11: Go to BIST Carrier Mode Page 790 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.143, "Steps for BIST Carrier Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.116, "BIST Carrier Mode Test" above. Table 8.143 Steps for BIST Carrier Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Carrier Mode, to put the UUT into BIST Carrier Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Carrier Mode. The Policy Engine goes to BIST Carrier Mode. 11 Protocol Layer tells PHY Layer to go into BIST Carrier Mode. UUT enters BIST Carrier Mode. 12 The Policy Engine directs the Protocol Layer to start generation of the Test Pattern. 13 Protocol Layer directs the PHY Layer to generate the Test Pattern. 14 PHY Layer receives the Test Pattern stream. PHY Layer generates a continuous Test Pattern stream. The UUT exits BIST Carrier Mode after tBISTContMode. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 791 8.3.2.15.2 BIST Test Data Mode The following is an example of a BIST Test Data Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.117, "BIST Test Data Test" shows the Messages as they flow across the bus and within the devices. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Test Data BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) Steps 2and 3 are repeated any number of times. 5) The test ends after Hard Reset Signaling is issued. See also Section 5.9.2, "BIST Test Data Mode" and Section 6.4.3.2, "BIST Test Data Mode". Page 792 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.117 BIST Test Data Test : Protocol 1: Send BIST(Test Data) : PHY : PHY : Protocol 2: BIST(Test Data) 3: BIST(Test Data) + CRC 4: BIST(Test Data) Start CRCReceiveTimer 5: BIST(Test Data) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Test Data) sent : Policy Engine : Policy Engine Go to BIST Test Data mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID End of Test (Hard Reset) Enter BIST Test Data mode 10: Send BIST(Test Data) 11: BIST(Test Data) 12: BIST(Test Data) + CRC 13: BIST(Test Data) Start CRCReceiveTimer 14: BIST(Test Data) received 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: BIST(Test Data) sent Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 793 Table 8.144, "Steps for BIST Test Data Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.117, "BIST Test Data Test" above. Table 8.144 Steps for BIST Test Data Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. UUT enters BIST Test Data Mode. 10 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Test Data, to put the UUT into BIST Test Data Mode. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 13 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. Page 794 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 14 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. The Policy Engine goes into BIST Test Data Mode Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. Repeat steps 10-18 any number of times The UUT exits BIST Test Data Mode after a Hard Reset Table 8.144 Steps for BIST Test Data Test Step Tester UUT Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 795 8.3.2.15.3 BIST Shared Capacity Test Mode The following is an example of a BIST Shared Capacity Test Mode test between a Tester and a UUT. When the UUT is connected to the Tester the sequence below is executed. Figure 8.118, "BIST Share Capacity Mode Test" shows the Messages as they flow across the bus and within the devices. This test places the UUT in a compliance test mode where the maximum Source capability is always offered on every Port, regardless of the availability of shared power i.e., all shared power management is disabled. 1) Connection is established and stable. 2) Tester sends a BIST Message with a BIST Shared Test Mode Entry BIST Data Object. 3) UUT answers with a GoodCRC Message. 4) UUT enters BIST Shared Capacity Test Mode. 5) Operator does the measurements. 6) Tester sends a BIST Message with a BIST Shared Test Mode Exit BIST Data Object. 7) UUT answers with a GoodCRC Message. 8) UUT exits BIST Shared Capacity Test Mode. See also Section 5.9.1, "BIST Carrier Mode" and Section 6.4.3.3, "BIST Shared Capacity Test Mode". Figure 8.118 BIST Share Capacity Mode Test 12: Send BIST(Shared Capacity Test Mode Exit) 13: BIST(Shared Capacity Test Mode Exit) 14: BIST(Shared Capacity Test Mode Exit) + CRC 15: BIST(Shared Capacity Test Mode Exit) Start CRCReceiveTimer 16: BIST(Shared Capacity Test Mode Exit) received 17: GoodCRC 18: GoodCRC + CRC 19: GoodCRC 20: BIST(Shared Capacity Test Mode) sent Go to BIST Shared Capacity Test Mode Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID EXit BIST Shared Capacity Test Mode mode 21: Exit BIST Shared Capacity Test Mode 22: Exit BIST Shared Capacity Test Mode : Protocol 1: Send BIST(Shared Capacity Test Mode Entry) : PHY : PHY : Protocol 2: BIST(Shared Capacity Test Mode Entry) 3: BIST(Shared Capacity Test Mode Entry) + CRC 4: BIST(Shared Capacity Test Mode Entry) Start CRCReceiveTimer 5: BIST(Shared Capacity Test Mode Entry) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: BIST(Shared Capacity Test Mode) sent : Policy Engine : Policy Engine Go to BIST Shared Capacity Test Mode Tester UUT Check and increment MessageIDCounter Stop CRCReceiveTimer Check MessageID against local copy Store copy of MessageID Enter BIST Shared Capacity Test Mode mode 10: Go to BIST Shared Capacity Test Mode 11: Go to BIST Shared Capacity Test Mode Tester Performs Tests Page 796 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.145, "Steps for BIST Shared Capacity Test Mode Test" below provides a detailed explanation of what happens at each labeled step in Figure 8.118, "BIST Share Capacity Mode Test" above. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT 1 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Entry, to put the UUT into BIST Shared Capacity Test Mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY LayerPHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 10 Policy Engine tells Protocol Layer to go into BIST Shared Capacity Test Mode. The Policy Engine goes to BIST Shared Capacity Test Mode. 11 Protocol Layer tells PHY Layer to go into BIST Shared Capacity Test Mode. UUT enters BIST Shared Capacity Test Mode. Tester performs tests. 12 The Policy Engine directs the Protocol Layer to generate a BIST Message, with a BIST Data Object of BIST Shared Test Mode Exit, to take the UUT out of BIST Shared Capacity Test Mode. 13 Protocol Layer creates the Message and passes to PHY Layer. 14 PHY Layer appends CRC and sends the BIST Message. Starts CRCReceiveTimer. PHY Layer receives the BIST Message and checks the CRC to verify the Message. 15 PHY Layer removes the CRC and forwards the BIST Message to the Protocol Layer. 16 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received BIST Message information to the Policy Engine that consumes it. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 797 17 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 18 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 19 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 20 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the BIST Message was successfully sent. 21 Policy Engine tells Protocol Layer to exit BIST Shared Capacity Test Mode. The Policy Engine exits to BIST Shared Capacity Test Mode. 22 Protocol Layer tells PHY Layer to exit BIST Shared Capacity Test Mode. UUT exits BIST Shared Capacity Test Mode. Table 8.145 Steps for BIST Shared Capacity Test Mode Test Step Tester UUT Page 798 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16 Enter USB 8.3.2.16.1 UFP Entering USB4 Mode 8.3.2.16.1.1 UFP Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the UFP. Figure 8.119, "UFP Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.119 UFP Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 799 Table 8.146, "Steps for UFP USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.119, "UFP Entering USB4 Mode (Accept)" above. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 800 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Both Port Partners enter [USB4] operation. Table 8.146 Steps for UFP USB4 Mode Entry (Accept) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 801 8.3.2.16.1.2 UFP Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the UFP. Figure 8.120, "UFP Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.120 UFP Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 802 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.147, "Steps for UFP USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.120, "UFP Entering USB4 Mode (Reject)" above. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 803 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.147 Steps for UFP USB4 Mode Entry (Reject) Step DFP UFP Page 804 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.1.3 UFP Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the UFP at this time. Figure 8.121, "UFP Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.121 UFP Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Wait 11: Wait 12: Wait + CRC 13: Wait 14: Wait received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Wait sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP UFP Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 805 Table 8.148, "Steps for UFP USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.121, "UFP Entering USB4 Mode (Wait)" above. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 806 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Port Partners do not enter [USB4] operation. Table 8.148 Steps for UFP USB4 Mode Entry (Wait) Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 807 8.3.2.16.2 Cable Plug Entering USB4 Mode 8.3.2.16.2.1 Cable Plug Entering USB4 Mode (Accept) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is a Valid mode of operation for the Cable Plug. Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.122 Cable Plug Entering USB4 Mode (Accept) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Accept 11: Accept 12: Accept + CRC 13: Accept 14: Accept received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Accept sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode entered DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 808 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.149, "Steps for Cable Plug USB4 Mode Entry (Accept)" below provides a detailed explanation of what happens at each labeled step in Figure 8.122, "Cable Plug Entering USB4 Mode (Accept)" above. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Accept Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Accept Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 809 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Accept Message was successfully sent. Cable Plug enters [USB4] operation. Table 8.149 Steps for Cable Plug USB4 Mode Entry (Accept) Step DFP Cable Plug Page 810 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.16.2.2 Cable Plug Entering USB4 Mode (Reject) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is an Invalid mode of operation for the Cable Plug. Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.123 Cable Plug Entering USB4 Mode (Reject) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 811 Table 8.150, "Steps for Cable Plug USB4 Mode Entry (Reject)" below provides a detailed explanation of what happens at each labeled step in Figure 8.123, "Cable Plug Entering USB4 Mode (Reject)" above. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Reject Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Reject Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Page 812 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Reject Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.150 Steps for Cable Plug USB4 Mode Entry (Reject) Step DFP Cable Plug Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 813 8.3.2.16.2.3 Cable Plug Entering USB4 Mode (Wait) This is an example of an Enter USB operation where the DFP requests [USB4] mode when this is not possible for the Cable Plug at this time. Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" shows the Messages as they flow across the bus and within the devices to accomplish the Enter USB process. Figure 8.124 Cable Plug Entering USB4 Mode (Wait) : Protocol 1: Send Enter_USB (USB4) : PHY : PHY : Protocol 2: Enter_USB (USB4) 3: Enter_USB (USB4) + CRC 4: Enter_USB (USB4) Start CRCReceiveTimer 5: Enter_USB (USB4) received 6: GoodCRC 7: GoodCRC + CRC 8: GoodCRC 9: Enter_USB (USB4) sent Start SenderResponseTimer 10: Send Reject 11: Reject 12: Reject + CRC 13: Reject 14: Reject received Stop SenderResponseTimer 15: GoodCRC 16: GoodCRC + CRC 17: GoodCRC 18: Reject sent Start CRCReceiveTimer : Policy Engine : Policy Engine USB4 Mode not entered; USB link is negotiated via legacy mechanisms DFP Cable Plug Check and increment MessageIDCounter Stop CRCReceiveTimer Store copy of MessageID Check and increment MessageIDCounter Stop CRCReceiveTimer Page 814 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.151, "Steps for Cable Plug USB4 Mode Entry (Wait)" below provides a detailed explanation of what happens at each labeled step in Figure 8.124, "Cable Plug Entering USB4 Mode (Wait)" above. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug 1 The Policy Engine directs the Protocol Layer to generate an Enter_USB Message to request entry to [USB4] mode. 2 Protocol Layer creates the Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Enter_USB Message. Starts CRCReceiveTimer. PHY Layer receives the Enter_USB Message and compares the CRC it calculated with the one sent to verify the Message. 4 PHY Layer removes the CRC and forwards the Enter_USB Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the received Enter_USB Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Enter_USB Message was successfully sent. Policy Engine starts SenderResponseTimer. 10 Policy Engine tells the Protocol Layer to form an Wait Message. 11 Protocol Layer creates the Message and passes to PHY Layer. 12 PHY Layer receives the Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Message. Starts CRCReceiveTimer. 13 Protocol Layer stores the MessageID of the incoming Message. 14 The Protocol Layer forwards the received Wait Message information to the Policy Engine that consumes it. 15 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 16 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 17 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 815 18 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Wait Message was successfully sent. Cable Plug does not enter [USB4] operation. Table 8.151 Steps for Cable Plug USB4 Mode Entry (Wait) Step DFP Cable Plug Page 816 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.2.17 Unstructured Vendor Defined Messages 8.3.2.17.1 Unstructured VDM Figure 8.125, "Unstructured VDM Message Sequence" shows an example sequence of an Unstructured VDM Transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.125 Unstructured VDM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send Unstructured VDM Start CRCReceive Timer 21 : Unstructured VDM 22 : Unstructured VDM + CRC 23 : Unstructured VDM Check MessageID against local copy Store Copy of MessageID 23 : Unstructured VDM Received Evaluate Unstructured VDM Reply with the application specific response which can be again a Unstructured VDM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send Unstructured VDM 11: Unstructured VDM 18: Unstructured VDM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : Unstructured VDM + CRC 16: GoodCRC + CRC 11: Unstructured VDM 15: GoodCRC 14: Unstructured VDM Received Process Unstructured VDM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : Unstructured VDM Sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 817 Table 8.152, "Steps for Unstructured VDM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.125, "Unstructured VDM Message Sequence" above. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send an Unstructured Vendor_Defined Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. PHY Layer receives the Unstructured Vendor_Defined Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Unstructured Vendor_Defined Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form an Unstructured Vendor_Defined Message. 11 Protocol Layer creates the Unstructured Vendor_Defined Message and passes to PHY Layer. 12 PHY Layer receives the Unstructured Vendor_Defined Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Unstructured Vendor_Defined Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Unstructured Vendor_Defined Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. Page 818 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Unstructured Vendor_Defined Message was successfully sent. Table 8.152 Steps for Unstructured VDM Message Sequence Step DFP UFP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 819 8.3.2.17.2 VDEM Figure 8.126, "VDEM Message Sequence" shows an example sequence of an VDEM transaction between a DFP and UFP. The figure below shows the Messages as they flow across the bus after UFP Enters into Modal Operation. Figure 8.126 VDEM Message Sequence : Protocol : DFP Policy Engine : PHY : PHY : Protocol : UFP Policy Engine New Mode Entered 20 : Send VDEM Start CRCReceive Timer 21 : VDEM 22 : VDEM + CRC 23 : VDEM Check MessageID against local copy Store Copy of MessageID 23 : VDEM Received Evaluate VDEM Reply with the application specific response which can be again a VDEM Start CRCReceive Timer Check and Increment MessageIDCounter Stop CRCReceiveTimer 10: Send VDEM 11: VDEM 18: VDEM Sent 17: GoodCRC Check MessageID against local copy Store Copy of MessageID 12 : VDEM + CRC 16: GoodCRC + CRC 11: VDEM 15: GoodCRC 14: VDEM Received Process VDEM as required 24 : GoodCRC 25 : GoodCRC + CRC 26 : GoodCRC Check and Increment MessageIDCounter Stop CRCReceiveTimer 27 : VDEM Sent Page 820 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Table 8.153, "Steps for VDEM Message Sequence" below provides a detailed explanation of what happens at each labeled step in Figure 8.126, "VDEM Message Sequence" above. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP 1 The DFP has an Explicit Contract and has entered an Active Mode with the UFP. The Policy Engine directs the Protocol Layer to send a Vendor_Defined_Extended Message. The UFP has an Explicit Contract and has entered an Active Mode with the UFP 2 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 3 PHY Layer appends CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. PHY Layer receives the Vendor_Defined_Extended Message and checks the CRC to verify the Message. 4 PHY Layer removes the CRC and forwards the Vendor_Defined_Extended Message to the Protocol Layer. 5 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 6 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 7 PHY LayerPHY Layer receives the GoodCRC Message and checks the CRC to verify the Message. PHY Layer appends CRC and sends the GoodCRC Message. 8 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 9 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. 10 In this example the Vendor protocol requires a response. The Policy Engine tells the Protocol Layer to form a Vendor_Defined_Extended Message. 11 Protocol Layer creates the Vendor_Defined_Extended Message and passes to PHY Layer. 12 PHY Layer receives the Vendor_Defined_Extended Message and compares the CRC it calculated with the one sent to verify the Message. PHY Layer appends a CRC and sends the Vendor_Defined_Extended Message. Starts CRCReceiveTimer. 13 Protocol Layer checks the MessageID in the incoming Message is different from the previously stored value and then stores a copy of the new value. The Protocol Layer forwards the Vendor_Defined_Extended Message information to the Policy Engine that consumes it. 14 Protocol Layer generates a GoodCRC Message and passes it PHY Layer. 15 PHY Layer appends a CRC and sends the GoodCRC Message. PHY Layer receives GoodCRC Message and compares the CRC it calculated with the one sent to verify the Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 821 16 PHY Layer removes the CRC and forwards the GoodCRC Message to the Protocol Layer. 17 Protocol Layer verifies and increments the MessageIDCounter and stops CRCReceiveTimer. Protocol Layer informs the Policy Engine that the Vendor_Defined_Extended Message was successfully sent. Table 8.153 Steps for VDEM Message Sequence Step DFP UFP Page 822 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3 State Diagrams 8.3.3.1 Introduction to state diagrams used in Chapter 8 The state diagrams defined in Section 8.3.3, "State Diagrams" are Normative and Shall define the operation of the Power Delivery Policy Engine. Note: These state diagrams are not intended to replace a well written and robust design. Figure 8.127 Outline of States Figure 8.127, "Outline of States" shows an outline of the states defined in the following sections. At the top there is the name of the state. This is followed by "Actions on entry" a list of actions carried out on entering the state. If there are also "Actions on exit" a list of actions carried out on exiting the state, then these are listed as well; otherwise, this box is omitted from the state. At the bottom the status of PD is listed:  “Power" which indicates the present output power for a Source Port or input power for a Sink Port.  “PD" which indicates the present Attachment status either "Attached", "Detached", or "unknown". Transitions from one state to another are indicated by arrows with the conditions listed on the arrow. Where there are multiple conditions, these are connected using either a logical OR "|" or a logical AND "&". In some cases, there are transitions which can occur from any state to a particular state. These are indicated by an arrow which is unconnected to a state at one end, but with the other end (the point) connected to the final state. In some state diagrams it is necessary to enter or exit from states in other diagrams (e.g., Source Port or Sink Port state diagrams). Figure 8.128, "References to states" indicates how such references are made. The reference is indicated with a hatched box. The box contains the name of the state and whether the state is a DFP or UFP. It has also been necessary to indicate conditional entry to either Source Port or Sink Port state diagrams. This is achieved by the use of a bulleted list indicating the preconditions (see example in Figure 8.129, "Example of state reference with conditions"). It is also possible that the entry and return states are the same. Figure 8.130, "Example of state reference with the same entry and exit" indicates a state reference where each referenced state corresponds to either the entry state or the exit state. <Name of State> Actions on entry: “List of actions to carry out on entering the state” Power (VI) = “Present power level” PD = “attachment status” Actions on exit: “List of actions to carry out on exiting the state” Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 823 Figure 8.128 References to states Figure 8.129 Example of state reference with conditions Figure 8.130 Example of state reference with the same entry and exit Timers are included in many of the states. Timers are initialized (set to their starting condition) and run (timer is counting) in the particular state it is referenced. As soon as the state is exited then the timer is no longer active. Where the timers continue to run outside of the state (such as the NoResponseTimer), this is called out in the text. Timeouts of the timers are listed as conditions on state transitions. The SenderResponseTimer is a special case, as it May be stopped and started from outside the states in which it is used. To allow this to be done without over-complicating the state diagrams, the SenderResponseTimer is described with its own state diagram (Figure 8.131, "SenderResponseTimer Policy Engine State Diagram"). The control of this Timer is shared between the Policy Engine and the Chunking Layer. <Name of reference state> (<DFP | UFP>) Hard Reset: • Consumer or Consumer/Provider -> PE_SNK_.... • Provider/Consumer in Source role -> PE_SRC_... <Name of reference state 1> or <Name of reference state 2> (<DFP | UFP>) Page 824 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Conditions listed on state transitions will come from one of three sources and, when there is a conflict, Should be serviced in the following order: 1) Message and related indications passed up to the Policy Engine from the Protocol Layer (Message sent; Message received etc.). 2) Events triggered within the Policy Engine e.g., timer timeouts. 3) Information and requests coming from the Device Policy Manager relating either to Local Policy, or to other modules which the Device Policy Manager controls such as power supply and USB-C® Port Control. Note: The following state diagrams are not intended to cover all possible corner cases that could be encountered. For example, where an outgoing Message is Discarded, due to an incoming Message by the Protocol Layer (see Section 6.12.2.3, "Protocol Layer Message Reception") it will be necessary for the higher layers of the system to handle a retry of the AMS that was being initiated, after first handling the incoming Message. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 825 8.3.3.1.1 SenderResponseTimer State Diagram Figure 8.131, "SenderResponseTimer Policy Engine State Diagram" below shows the state diagram for the Policy Engine in a Source Port or a Sink Port. The following sections describe operation in each of the states. Figure 8.131 SenderResponseTimer Policy Engine State Diagram 8.3.3.1.1.1 SRT_Stopped State The SRT_Stopped State Shall be the starting state for the SenderResponseTimer either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall stop incrementing the SR_Timer. The Policy Engine Shall transition to the SRT_Running State:  When the SenderResponseTimer is started from within a Policy Engine state, or  When a Start_SRT is requested from the Chunking Layer. 8.3.3.1.1.2 SRT_Running State On entry to the SRT_Running State the SenderResponseTimer state machine Shall:  Set the SR_Timer to zero  Start running SR_Timer. The SenderResponseTimer state machine Shall transition to the SRT_Expired State:  When the SR_Timer reaches its maximum count The SenderResponseTimer state machine Shall transition to the SRT_Stopped State:  When the SenderResponseTimer is stopped by exiting a Policy Engine state, or  When a Stop_SRT is requested from the Chunking Layer SRT_Stopped Actions on entry: Stop Incrementing SR_Timer1 Power-up | Hard Reset | SenderResponseTimer stopped on exit from Policy Engine State | Stop_SRT requested from Chunking Layer Actions on entry: Zero SR_Timer Start Incrementing SR_Timer1 SRT_Running SenderResponseTimer started from within Policy Engine State | Start_SRT requested from Chunking Layer Actions on entry: Inform Policy Engine of SenderResponseTimer timeout SRT_Expired SR_Timer1 reached maximum count Policy Engine informed 1) The SR_Timer is regarded as the mechanism within the SenderResponseTimer state diagram that implements the SenderResponseTimer. Page 826 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.1.1.3 SRT_Expired State On entry to the SRT_Running State the SenderResponseTimer state machine Shall Inform Policy Engine of SenderResponseTimer timeout The Policy Engine Shall then transition to the SRT_Stopped state:  When the Policy Engine has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 827 8.3.3.2 Policy Engine Source Port State Diagram Figure 8.132, "Source Port State Diagram" below shows the state diagram for the Policy Engine in a Source Port. The following sections describe operation in each of the states. Figure 8.132 Source Port State Diagram 1) Implementation of the CapsCounter is Optional. In the case where this is not implemented the Source Shall continue to send Source_Capabilities Messages each time the SourceCapabilityTimer times out. 2) Since the Sink is required to make a Valid request from the offered capabilities the expected transition is via "Request can be met" unless the Source Capabilities have changed since the last offer. 3) “Contract Invalid" means that the previously Negotiated voltage and Current values are no longer included in the Source's new Capabilities. If the Sink fails to make a Valid Request in this case, then Power Delivery operation is no lon- ger possible and Power Delivery mode is exited with a Hard Reset. Protocol LayerReset4 | SwapSourceStartTimer timeout PE_SRC_Discovery Actions on entry: Initialize and run SourceCapabilityTimer Power = Default (5V) or Implicit Contract PD = not Connected PE_SRC_Ready Actions on entry: Notify Protocol Layer of end of AMS8 Initialize and run DiscoverIdentityTimer7 Initialize and run SourcePPSCommTimer10 Initialize and run SourceEPRKeepAliveTimer11 Power = Explicit Contract PD = Connected PE_SRC_Transition_Supply Actions on entry: Send Accept message (within tReceiverResponse) Request Device Policy Manager to transition Power Supply Power = transition PD = Connected Actions on exit: Send PS_RDY message (In SPR Mode & Request Message) | (In EPR Mode & EPR_Request Message) PE_SRC_Negotiate_Capability Actions on entry: Get Device Policy Manager evaluation of sink request: • Can be met • Can’t be met • Could be met later from Power Reserve If the sink request for Operating Current or Operating Power can be met, but the sink still requires more power (“Capability Mismatch”) this information will be passed to Device Policy Manager4 Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SRC_Capability_Response Actions on entry: Send Reject message if request can’t be met Send Wait message if request could be met later from the Power Reserve and present Contract is still valid Power = DefauIt (5V) or Implicit/ Explicit Contract PD = Connected Start Explicit Contract (Reject message sent & Contract still valid) | Wait message sent PE_SRC_Send_Capabilities Actions on entry: Request present source capabilities from Device Policy Manager In SPR Mode Send Source_Capabilities Message In EPR Mode Send EPR_Source_Capabilities Message Increment CapsCounter (optional)1 If GoodCRC received: • stop NoResponseTimer • reset HardResetCounter and CapsCounter • initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SRC_Hard_Reset Actions on entry: Generate Hard Reset signalling Initialize and start NoResponseTimer Start PSHardResetTimer Increment HardResetCounter Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Request can’t be met | Request met later from Power Reserve Explicit Contract & Reject message sent & Contract Invalid4 PSHardResetTimer timeout Request can be met Power supply ready Power source at default (SourceCapabilityTimer timeout & CapsCounter ” nCapsCount1) Capabilities message sending failure (without GoodCRC) ¬ presently PD Connected6 In SPR Mode Request Message received | In EPR Mode EPR_Request Message received PE_SRC_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager12 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Hard reset signalling received SenderResponseTimer timeout not previously PD Connected6& NoResponseTimer timeout & HardResetCounter > nHardResetCount1 PSHardResetTimer timeout (SourceCapabilityTimer timeout & CapsCounter > nCapsCount1) | (not previously PD Connected6 & NoResponseTimer timeout & HardResetCounter > nHardResetCount1) PE_SRC_Startup Actions on entry: Reset CapsCounter Reset Protocol Layer Start SwapSourceStartTimer (only after Swap) Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SRC_Transition_to_default Actions on entry: Request Device Policy Manager to request power supply Hard Resets to vSafe5V via vSafe0V Reset local HW Request Device Policy Manager to set Port Data Role to DFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected PE_SRC_Disabled Actions on entry: Disable Power Delivery Power = DefauIt (5V) PD =not Connected Actions on exit: Request Device Policy Manager to turn on VCONN Inform Protocol Layer Hard Reset complete ErrorRecovery previously PD Connected6 & NoResponseTimer timeout & HardResetCount > nHardResetCount PE_SRC_Wait_New_Capabilities Actions on entry: Wait for new Source Capabilities9 Power = DefauIt (5V) PD =Connected PE_SRC_Hard_Reset_Received Actions on entry: Start PSHardResetTimer Initialize and start NoResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected Source capability change (from Device Policy Manager) no Explicit Contract & (Reject message sent | Wait message sent) Source capability change (from Device Policy Manager) | (In SPR Mode & Get_Source_Cap Message) | (In EPR Mode & EPR_Get_Source_Cap Message) Protocol Error Actions on exit: If the Source is initiating an AMS then notify the Protocol Layer than the first Message in an AMS will follow8 SourcePPSCommTimer timeout | SourceEPRKeepAliveTimer timeout PE_SRC_EPR_Keep_Alive Actions on entry: Send EPR_Keep_Alive_Ack Message Power = Explicit Contract PD = Connected EPR_Keep_Alive Message EPR_Keep_Alive_Ack Sent Hard Reset request from Device Policy Manager | EPR Mode & Request Message received | EPR Capable & SPR Mode & EPR_Request Message received (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities message sent PE_SRC_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Page 828 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) After a Power Swap the New Source is required to wait an additional tSwapSourceStart before sending a Source_Capabilities Message. This delay is not required when first starting up a system. 5) PD Connected is defined as a situation when the Port Partners are actively communicating. The Port Partners remain PD Connected after a Swap until there is a transition to Disabled or the connector is able to identify a Detach. 6) Port Partners are no longer PD Connected after a Hard Reset, but consideration needs to be given as to whether there has been a PD Connection while the Ports have been Attached to prevent unnecessary USB Type-C Error Recovery. 7) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 8) See Section 5.7, "Collision Avoidance", Section 6.6.16, "Collision Avoidance Timers" and Section 6.10, "Collision Avoidance". 9) In the PE_SRC_Wait_New_Capabilities State the Device Policy Manager Should either decide to send no further Source Capabilities or Should send a different set of Source Capabilities. Continuing to send the same set of Source Capabilities could result in a live lock situation. 10) The SourcePPSCommTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sourc- es that do not support SPR PPS do not need to implement the SourcePPSCommTimer. 11) The SourceEPRKeepAliveTimer is only initialized and run when the Source is in EPR Mode; Sources that do not support EPR Mode do not need to implement the SourceEPRKeepAliveTimer. 12) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. 8.3.3.2.1 PE_SRC_Startup State PE_SRC_Startup Shall be the starting state for a Source Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the CapsCounter and reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state:  When the Protocol Layer reset has completed if the PE_SRC_Startup state was entered due to the system first starting up.  When the SwapSourceStartTimer times out if the PE_SRC_Startup state was entered as the result of a Power Role Swap. Note: Sources Shall remain in the PE_SRC_Startup state, without sending any Source_Capabilities Messages until a plug is Attached. 8.3.3.2.2 PE_SRC_Discovery State On entry to the PE_SRC_Discovery state the Policy Engine Shall initialize and run the SourceCapabilityTimer in order to trigger sending a Source_Capabilities Message. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The SourceCapabilityTimer times out and CapsCounter ≤ nCapsCount. The Policy Engine May Optionally go to the PE_SRC_Disabled state when:  The Port Partners are not presently PD Connected  And the SourceCapabilityTimer times out  And CapsCounter > nCapsCount. The Policy Engine Shall go to the PE_SRC_Disabled state when:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 829  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. Note: In the PE_SRC_Disabled state the Attached device is assumed to be unresponsive. The Policy Engine operates as if the device is Detached until such time as a Detach/Re-attach is detected. 8.3.3.2.3 PE_SRC_Send_Capabilities State Note: This state can be entered from the PE_SRC_Soft_Reset state. On entry to the PE_SRC_Send_Capabilities state the Policy Engine Shall request the present Port capabilities from the Device Policy Manager. The Policy Engine Shall then request the Protocol Layer to send a capabilities Message containing these capabilities. The Policy Engine Shall request:  A Source_Capabilities Message if the Source is in SPR Mode or  An EPR_Source_Capabilities Message if the Source is in EPR Mode. The Policy Engine Shall then increment the CapsCounter (if implemented). If a GoodCRC Message is received, then the Policy Engine Shall:  Stop the NoResponseTimer.  Reset the HardResetCounter and CapsCounter to zero. Note: The HardResetCounter Shall only be set to zero in this state and at power up; its value Shall be maintained during a Hard Reset.  Initialize and run the SenderResponseTimer. Once a Source_Capabilities Message has been received and acknowledged by a GoodCRC Message, the Sink is required to then send a Request Message within tSenderResponse. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received from the Sink and the Source is operating in SPR Mode or  An EPR_Request Message is received from the Sink and the Source is operating in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Discovery state when:  The Protocol Layer indicates that the Message has not been sent and we are presently not Connected. This is part of the Capabilities sending process whereby successful Message sending indicates connection to a PD Sink Port. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The SenderResponseTimer times out. In this case a transition back to USB Default Operation is required. When:  The Port Partners have not been PD Connected (the Source Port remains Attached to a Port it has not had a PD Connection with during this Attachment)  And the NoResponseTimer times out  And the HardResetCounter > nHardResetCount. The Policy Engine Shall do one of the following:  Transition to the PE_SRC_Discovery state.  Transition to the PE_SRC_Disabled state. Page 830 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: That in either case the Attached device is assumed to be unresponsive. The Policy Engine Should operate as if the device is Detached until such time as a Detach/Re-attach is detected. The Policy Engine Shall go to the ErrorRecovery state when:  The Port Partners have previously been PD Connected (the Source Port remains Attached to a Port it has had a PD Connection with during this Attachment)  And the NoResponseTimer times out.  And the HardResetCounter > nHardResetCount. 8.3.3.2.4 PE_SRC_Negotiate_Capability State On entry to the PE_SRC_Negotiate_Capability state the Policy Engine Shall ask the Device Policy Manager to evaluate the Request from the Attached Sink. The response from the Device Policy Manager Shall be one of the following:  The Request can be met.  The Request cannot be met  The Request could be met later from the Power Reserve. The Policy Engine Shall transition to the PE_SRC_Transition_Supply state when:  The Request can be met. The Policy Engine Shall transition to the PE_SRC_Capability_Response state when:  The Request cannot be met.  Or the Request can be met later from the Power Reserve. 8.3.3.2.5 PE_SRC_Transition_Supply State The Policy Engine Shall be in the PE_SRC_Transition_Supply state while the power supply is transitioning from one power to another. On entry to the PE_SRC_Transition_Supply state, the Policy Engine Shall request the Protocol Layer to send an Accept Message and inform the Device Policy Manager that it Shall transition the power supply to the Requested power level. Note: If the power supply is currently operating at the requested power no change will be necessary. On exit from the PE_SRC_Transition_Supply state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The Device Policy Manager informs the Policy Engine that the power supply is ready. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.2.6 PE_SRC_Ready State In the PE_SRC_Ready state the PD Source Shall be operating at a stable power with no ongoing Negotiation. It Shall respond to requests from the Sink, events from the Device Policy Manager. On entry to the PE_SRC_Ready state the Source Shall notify the Protocol Layer of the end of the Atomic Message Sequence (AMS). If the transition into PE_SRC_Ready is the result of Protocol Error that has not caused a Soft Reset (see Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram") then the notification to the Protocol Layer of the end of the AMS Shall Not be sent since there is a Message to be processed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 831 On entry to the PE_SRC_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, the Policy Engine Shall:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). On entry to the PE_SRC_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SourcePPSCommTimer. On entry to the PE_SRC_Ready state if the current Explicit Contract is for EPR Mode, then the Policy Engine Shall do the following:  Initialize and run the SourceEPRKeepAliveTimer. On exit from the PE_SRC_Ready, if the Source is initiating an AMS, then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed or  A Get_Source_Cap Message is received, and the Source is in SPR Mode or  An EPR_Get_Source_Cap Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Negotiate_Capability state when:  A Request Message is received, and the Source is in SPR Mode or  An EPR_Request Message is received, and the Source is in EPR Mode. The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap state when:  The Device Policy Manager asks for the Sink Capabilities. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Source is operating as an SPR PPS and the SourcePPSCommTimer Timer times-out or  The Source is in EPR Mode and the SourceEPRKeepAliveTimer Timer times-out. The Policy Engine Shall transition to the PE_SRC_EPR_Keep_Alive state when:  An EPR_KeepAlive Message is received. The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap State when:  In EPR Mode and a Get_Source_Cap Message is received or  In SPR Mode and an EPR_Get_Source_Cap Message is received. 8.3.3.2.7 PE_SRC_Disabled State In the PE_SRC_Disabled state the PD Source supplies default power and is unresponsive to USB Power Delivery messaging, but not to Hard Reset Signaling. 8.3.3.2.8 PE_SRC_Capability_Response State The Policy Engine Shall enter the PE_SRC_Capability_Response state if there is a Request received from the Sink that cannot be met based on the present capabilities. When the present Explicit Contract is not within the present capabilities it is regarded as Invalid and a Hard Reset will be triggered. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall request the Protocol Layer to send one of the following: Page 832 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  Reject Message - if the request cannot be met or the present Explicit Contract is Invalid.  Wait Message - if the request could be met later from the Power Reserve. A Wait Message Shall Not be sent if the present Explicit Contract is Invalid. The Policy Engine Shall transition to the PE_SRC_Ready state when:  There is an Explicit Contract and  A Reject Message has been sent and the present Explicit Contract is still Valid or  A Wait Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  There is an Explicit Contract and  The Reject Message has been sent and the present Explicit Contract is Invalid (i.e., the Sink had to request a new value so instead we will return to USB Default Operation). The Policy Engine Shall transition to the PE_SRC_Wait_New_Capabilities state when:  There is no Explicit Contract and  A Reject Message has been sent or  A Wait Message has been sent. 8.3.3.2.9 PE_SRC_Hard_Reset State The Policy Engine Shall transition to the PE_SRC_Hard_Reset state from any state when:  Hard Reset request from Device Policy Manager or  In EPR Mode and a Request Message is received or  EPR Capable and in SPR Mode and an EPR_Request Message is received. On entry to the PE_SRC_Hard_Reset state the Policy Engine Shall:  request the generation of Hard Reset Signaling by the PHY Layer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out.  initialize and run the PSHardResetTimer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when:  The PSHardResetTimer times out. 8.3.3.2.10 PE_SRC_Hard_Reset_Received State The Policy Engine Shall transition from any state to the PE_SRC_Hard_Reset_Received state when:  Hard Reset Signaling is detected. On entry to the PE_SRC_Hard_Reset_Received state the Policy Engine Shall:  initialize and run the PSHardResetTimer  initialize and run the NoResponseTimer. Note: The NoResponseTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SRC_Transition_to_default state when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 833  The PSHardResetTimer times out. 8.3.3.2.11 PE_SRC_Transition_to_default State On entry to the PE_SRC_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the power supply Shall Hard Reset (see Section 7.1.5, "Response to Hard Resets").  request a reset of the local hardware  request the Device Policy Manager to set the Port Data Role to DFP and turn off VCONN. On exit from the PE_SRC_Transition_to_default state the Policy Engine Shall:  request the Device Policy Manager to turn on VCONN  inform the Protocol Layer that the Hard Reset is complete. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Device Policy Manager indicates that the power supply has reached the default level. 8.3.3.2.12 PE_SRC_Get_Sink_Cap State In this state the Policy Engine, due to a request from the Device Policy Manager, Shall request the capabilities from the Attached Sink. On entry to the PE_SRC_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SRC_Ready state when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. 8.3.3.2.13 PE_SRC_Wait_New_Capabilities State In this state the Policy Engine has been unable to Negotiate an Explicit Contract and is waiting for new Capabilities from the Device Policy Manager. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The Device Policy Manager indicates that Source Capabilities have changed. 8.3.3.2.14 PE_SRC_EPR_Keep_Alive State On entry to the PE_SRC_EPR_Keep_Alive State the Policy Engine Shall send a EPR_KeepAlive_Ack Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_KeepAlive_Ack Message has been sent. Page 834 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.2.15 8.3.3.2.15PE_SRC_Give_Source_Cap State  On entry to the PE_SRC_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Source Capabilities Message has been successfully sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 835 8.3.3.3 Policy Engine Sink Port State Diagram Figure 8.133, "Sink Port State Diagram" below shows the state diagram for the Policy Engine in a Sink Port. The following sections describe operation in each of the states. Figure 8.133 Sink Port State Diagram 1) Source Capabilities Messages received in States other than PE_SNK_Wait_for_Capabilities, PE_SNK_Ready or PE_SNK_Get_Source_Cap constitute a Protocol Error. 2) The SinkRequestTimer Should Not be stopped if a Ping (Deprecated) Message is received in the PE_SNK_Ready state since it represents the maximum time between requests after a Wait Message which is not reset by a Ping (Deprecat- ed) Message. 3) During a Hard Reset the Source voltage will transition to vSafe0V and then transition to vSafe5V. Sinks need to ensure that VBUS present is not indicated until after the Source has completed the Hard Reset process by detecting both of these transitions. New power required | SinkRequestTimer Timeout | SinkPPSPeriodicTimer Timeout Start Explicit Contract & (Reject message received | Wait message received) Hard reset signalling received Power Sink at default Protocol Layer Reset Hard Reset complete VBUS 6 present3 ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source_Capabilities Message received))1 Device Policy Manager Response received Accept message received PS_RDY message received Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink capabilities message sent ((SinkWaitCapTimer timeout | PSTransitionTimer timeout) & (HardResetCounter ” nHardResetCount)) | Hard Reset request from Device Policy Manager | EPR Mode & (EPR_Source _Capabilites message with An EPR PDO in positions 1..7 | Source_Capabilities Message not requested by Get_Source_caps) PE_SNK_Startup Actions on entry: Reset Protocol Layer Power = DefauIt (0V or 5V) or Implicit Contract PD = Connected/not Connected SenderResponseTimer Timeout PE_SNK_Discovery Actions on entry: Wait for VBUS 6 Power = Default (0V or 5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Wait_for_Capabilities Actions on entry: Initialize and run SinkWaitCapTimer Power = Default (5V) or Implicit Contract PD = Connected/not Connected PE_SNK_Evaluate_Capability Actions on entry: Reset HardResetCounter to zero. Ask Device Policy Manager to evaluate the options based on supplied capabilities, any Power Reserve that it needs, and respond indicating the selected capability and, Optionally, a “Capability Mismatch”. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Select_Capability Actions on entry: Send Request based on Device Policy Manager response: • Request from present capabilities • Optionally Indicate that other capabilities would be preferred (“Capability Mismatch”) Initialize and run SenderResponseTimer Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected PE_SNK_Transition_Sink Actions on entry: Initialize and run PSTransitionTimer Power = transition PD = Connected Actions on exit: Request Device Policy Manager transitions sink power supply to new power (if required) PE_SNK_Ready Actions on entry: Initialize and run SinkRequestTimer2 (on receiving Wait) Initialize and run DiscoverIdentityTimer4 Initialize and run the SinkPPSPeriodicTimer5 In EPR Mode Initialize and run the SinkEPRKeepAliveTimer8 If Sink supports Fast Role Swap send Get_Sink_Cap Message7 Power = Explicit Contract PD = Connected PE_SNK_Give_Sink_Cap Actions on entry: Get present sink capabilities from Device Policy Manager Send Capabilities message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected PE_SNK_Hard_Reset Actions on entry: Generate Hard Reset signalling. Increment HardResetCounter. Power = DefauIt (5V) or Implicit/Explicit Contract PD = Connected/not Connected PE_SNK_Transition_to_default Actions on entry: Request Device Policy Manager to request power sink transition to default Reset local HW Set Port Data Role to UFP and turn off VCONN Power = rising/falling to default (5V) PD = not Connected Actions on exit: Inform Protocol Layer Hard Reset complete no Explicit Contract & (Reject message received | Wait message received) ((SPR Mode & Source_Capabilities Message) | (EPR Mode & EPR_Source Capabilities Message))1 Actions on exit: If the Sink is initiating an AMS then notify the Protocol Layer that the first Message in the AMS will follow. Protocol Error PE_SNK_EPR_Keep_Alive Actions on entry: Send EPR_KeepAlive Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected SinkEPRKeepAliveTimer Timeout EPR_KeepAlive_Ack Message SenderResponseTimer Timeout PE_SNK_Get_Source_Cap Actions on entry: If SPR Mode capabilities requested send Get_Source_Cap Message If EPR Mode capabilities requested send EPR_Get_Source_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get source capabilities request from Device Policy Manager (EPR Mode & SPR Source Capabilities requested & Source_Capabilities Message received) | (SPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message received) | SenderResponseTimer timeout Actions on exit: Pass Source capabilities/outcome to Device Policy Manager (SPR Mode & SPR Source Capabilities requested & Source_Capabilities Message) | (EPR MODE & EPR Source Capabilities requested & EPR_Source_Capabilities Message) Page 836 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 4) The DiscoverIdentityTimer is run when this is a VCONN Source and a PD Connection with a Cable Plug needs to be es- tablished i.e. no GoodCRC Message has yet been received in response to a Discover Identity Command. 5) The SinkPPSPeriodicTimer is only initialized and run when the present Explicit Contract is for an SPR PPS APDO. Sinks that do not support PPS do not need to implement the SinkPPSPeriodicTimer. 6) A Sink that is a VPD May use VCONN as a proxy for VBUS. 7) To be sent once, and only required if Fast Role Swap is supported by the Sink. 8.3.3.3.1 PE_SNK_Startup State PE_SNK_Startup Shall be the starting state for a Sink Policy Engine either on power up or after a Hard Reset. On entry to this state the Policy Engine Shall reset the Protocol Layer. Note: Resetting the Protocol Layer will also reset the MessageIDCounter and stored MessageID (see Section 6.12.2.3, "Protocol Layer Message Reception"). Once the reset process completes, the Policy Engine Shall transition to the PE_SNK_Discovery state. 8.3.3.3.2 PE_SNK_Discovery State In the PE_SNK_Discovery state the Sink Policy Engine waits for VBUS to be present. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Device Policy Manager indicates that VBUS has been detected. 8.3.3.3.3 PE_SNK_Wait_for_Capabilities State On entry to the PE_SNK_Wait_for_Capabilities state the Policy Engine Shall initialize and start the SinkWaitCapTimer. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  The Sink is in SPR Mode and a Source_Capabilities Message is received or  The Sink is in EPR Mode and an EPR_Source_Capabilities Message is received. When the SinkWaitCapTimer times out, the Policy Engine will perform a Hard Reset. 8.3.3.3.4 PE_SNK_Evaluate_Capability State The PE_SNK_Evaluate_Capability state is first entered when the Sink receives its first Source_Capabilities Message from the Source. At this point the Sink knows that it is Attached to and communicating with a PD capable Source. On entry to the PE_SNK_Evaluate_Capability state the Policy Engine Shall request the Device Policy Manager to evaluate the supplied Source Capabilities based on Local Policy. The Device Policy Manager Shall indicate to the Policy Engine the new power level required, selected from the present offered capabilities. The Device Policy Manager Shall also indicate to the Policy Engine a Capabilities Mismatch if the offered power does not meet the device's requirements. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A response is received from the Device Policy Manager. 8.3.3.3.5 PE_SNK_Select_Capability State On entry to the PE_SNK_Select_Capability state the Policy Engine Shall request the Protocol Layer to send a response Message, based on the evaluation from the Device Policy Manager. The Message Shall be one of the following:  A Request from the offered Source Capabilities. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 837  A Request from the offered Source Capabilities with an indication that another power level would be preferred (Capability Mismatch bit set). When in SPR Mode a Request Message Shall be sent. When in EPR Mode an EPR_Request Message Shall be sent. The Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Transition_Sink state when:  An Accept Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  There is no Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Ready state when:  There is an Explicit Contract in place and  A Reject Message is received from the Source or  A Wait Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs. 8.3.3.3.6 PE_SNK_Transition_Sink State On entry to the PE_SNK_Transition_Sink state the Policy Engine Shall initialize and run the PSTransitionTimer (timeout will lead to a Hard Reset see Section 8.3.3.3.8, "PE_SNK_Hard_Reset State" and Shall then request the Device Policy Manager to transition the Sink's power supply to the new power level. Note: If there is no power level change the Device Policy Manager Should Not affect any change to the power supply. On exit from the PE_SNK_Transition_Sink state the Policy Engine Shall request the Device Policy Manager to transition the Sink's power supply to the new power level. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A PS_RDY Message is received from the Source. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A Protocol Error occurs. 8.3.3.3.7 PE_SNK_Ready State In the PE_SNK_Ready state the PD Sink Shall be operating at a stable power level with no ongoing Negotiation. It Shall respond to requests from the Source, events from the Device Policy Manager. On entry to the PE_SNK_Ready state as the result of a wait the Policy Engine Should do the following:  Initialize and run the SinkRequestTimer. On entry to the PE_SNK_Ready state if this is a VCONN Source which needs to establish communication with a Cable Plug, then the Policy Engine Shall do the following:  Initialize and run the DiscoverIdentityTimer (no GoodCRC Message response yet received to Discover Identity Message). Page 838 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Ready state if the current Explicit Contract is for an SPR PPS APDO, then the Policy Engine Shall do the following:  Initialize and run the SinkPPSPeriodicTimer. On entry to the PE_SNK_Ready state if the Sink supports Fast Role Swap, then the Policy Engine Shall do the following:  Send a Get_Sink_Cap Message. On exit from the PE_SNK_Ready state, if the transition is as a result of a DPM request to start a new Atomic Message Sequence (AMS) then the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability state when:  In SPR Mode and a Source_Capabilities Message is received or  In EPR Mode and an EPR_Source_Capabilities Message is received. The Policy Engine Shall transition to the PE_SNK_Select_Capability state when:  A new power level is requested by the Device Policy Manager or  A SinkRequestTimer timeout occurs or  A SinkPPSPeriodicTimer timeout occurs. The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap state when:  Get_Sink_Cap Message is received or  EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap state when:  The Device Policy Manager requests an update of the remote Source Capabilities. The Policy Engine Shall transition to the PE_SNK_EPR_Keep_Alive state when:  The SinkEPRKeepAliveTimer timeouts out. 8.3.3.3.8 PE_SNK_Hard_Reset State The Policy Engine Shall transition to the PE_SNK_Hard_Reset state from any state when:  (PSTransitionTimer times out) and  (HardResetCounter ≤ nHardResetCount)) |  Hard Reset request from Device Policy Manager or  In EPR Mode and  An EPR_Source_Capabilities Message is received with an EPR (A)PDO in object positions 1…7 or  A Source_Capabilities Message is received that has not been requested using a Get_Source_Cap Message. The Policy Engine May transition to the PE_SNK_Hard_Reset state from any state when:  SinkWaitCapTimer times out Note: If the SinkWaitCapTimer times out and the HardResetCounter is greater than nHardResetCount the Sink Shall assume that the Source is non-responsive. Note: The HardResetCounter is reset on a power cycle or Detach. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 839 On entry to the PE_SNK_Hard_Reset state the Policy Engine Shall request the generation of Hard Reset Signaling by the PHY Layer and increment the HardResetCounter. The Policy Engine Shall transition to the PE_SNK_Transition_to_default state when:  The Hard Reset is complete. 8.3.3.3.9 PE_SNK_Transition_to_default State The Policy Engine Shall transition from any state to PE_SNK_Transition_to_default state when:  Hard Reset Signaling is detected. When Hard Reset Signaling is received or transmitted then the Policy Engine Shall transition from any state to PE_SNK_Transition_to_default. This state can also be entered from the PE_SNK_Hard_Reset state. On entry to the PE_SNK_Transition_to_default state the Policy Engine Shall:  indicate to the Device Policy Manager that the Sink Shall transition to default  request a reset of the local hardware  request the Device Policy Manager that the Port Data Role is set to UFP. The Policy Engine Shall transition to the PE_SNK_Startup state when:  The Device Policy Manager indicates that the Sink has reached the default level. 8.3.3.3.10 PE_SNK_Give_Sink_Cap State  On entry to the PE_SNK_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Sink_Capabilities Message has been successfully sent. 8.3.3.3.11 PE_SNK_EPR_Keep_Alive On entry to the PE_SNK_EPR_Keep_Alive State the Policy Engine Shall send an EPR_KeepAlive Message and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A EPR_KeepAlive_Ack Message is received. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The SenderResponseTimer times out. 8.3.3.3.12 PE_SNK_Get_Source_Cap State  On entry to the PE_SNK_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. Page 840 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On exit from the PE_SNK_Get_Source_Cap State the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition to the PE_SNK_Ready state when:  In EPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In SPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. The Policy Engine Shall transition to the PE_SNK_Evaluate_Capability State when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 841 8.3.3.4 SOP Soft Reset and Protocol Error State Diagrams 8.3.3.4.1 SOP Source Port Soft Reset and Protocol Error State Diagram Figure 8.134, "SOP Source Port Soft Reset and Protocol Error State Diagram" below shows the state diagram for the Policy Engine in a Source Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.134 SOP Source Port Soft Reset and Protocol Error State Diagram 8.3.3.4.1.1 PE_SRC_Send_Soft_Reset State The PE_SRC_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during a Non-interruptible AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response or  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  The Source is in the PE_SRC_Send_Capabilities state, there is a Source_Capabilities Message sending failure on SOP (without a GoodCRC Message) and the Source is not presently Attached (as indicated in Figure 8.132, "Source Port State Diagram"). In this case, the PE_SRC_Discovery state is entered (see Section 8.3.3.2.2, "PE_SRC_Discovery State").  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.2, "Policy Engine Source Port State Diagram"). In this case Hard Reset Signaling will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case USB Type-C Error Recovery will be triggered directly.  During a Data Role Swap when there is a mismatch in the Port Data Role field (see Section 6.2.1.1.6, "Port Data Role"). In this case USB Type-C Error Recovery will be triggered directly. PE_SRC_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept message Received from SOP Accept message Sent to SOP Soft Reset message Received on SOP PE_SRC_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SRC_Send_Capabilities Transmission Error indication from Protocol Layer PE_SRC_Ready In Explicit Contract & Protocol Error2 before first Message in AMS sent (no GoodCRC received) PE_SRC_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message received on SOP will result in a Not_Supported Message response being generated on SOP (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Source during the EPR Mode entry process. Page 842 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SRC_Ready state where the Message received will be handled as if it had been received in the PE_SRC_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. On entry to the PE_SRC_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message to the Sink on SOP, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.1.2 PE_SRC_Soft_Reset State The PE_SRC_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SRC_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state (see Section 8.3.3.2.3, "PE_SRC_Send_Capabilities State") when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 843 8.3.3.4.2 SOP Sink Port Soft Reset and Protocol Error State Diagram Figure 8.135, "Sink Port Soft Reset and Protocol Error Diagram" below shows the state diagram for the Policy Engine in a Sink Port when performing a Soft Reset of its Port Partner i.e., using SOP. The following sections describe operation in each of the states. Figure 8.135 Sink Port Soft Reset and Protocol Error Diagram 8.3.3.4.2.1 PE_SNK_Send_Soft_Reset State The PE_SNK_Send_Soft_Reset state Shall be entered from any state when:  A Protocol Error on SOP is detected by the Protocol Layer during an AMS (see Section 6.8.1, "Soft Reset and Protocol Error") or  A Message has not been sent after retries to the Sink or  When not in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response.  When in SPR Mode and the EPR Mode entry process fails. The main exceptions to this rule are when:  When the voltage is in transition due to a new Explicit Contract being Negotiated (see Section 8.3.3.3, "Policy Engine Sink Port State Diagram"). In this case a Hard Reset will be generated.  During a Power Role Swap when the power supply is in transition (see Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram"). In this case a Hard Reset will be triggered directly.  During a Data Role Swap when the DFP/UFP Data Roles are changing. In this case USB Type-C Error Recovery will be triggered directly. Note: Protocol Errors occurring in the following situations Shall Not lead to a Soft Reset, but Shall result in a transition to the PE_SNK_Ready state where the Message received will be handled as if it had been received in the PE_SNK_Ready state:  When in an Explicit Contract and Protocol Errors occurred on SOP during any AMS where the first Message in the AMS has not yet been sent i.e., an unexpected Message is received instead of the expected GoodCRC Message response. PE_SNK_Send_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Soft Reset Message to SOP Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP (no GoodCRC received)1 | Protocol Error2 on SOP during AMS | (Not in Explicit Contract & Protocol Error on SOP before first Message in AMS sent (no GoodCRC received) | (SPR Mode & EPR Mode Entry process fails)3 SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer Accept Message Received on SOP Accept Message Sent to SOP Soft Reset Message Received on SOP PE_SNK_Soft_Reset Actions on entry: Reset SOP Protocol Layer Send Accept Message to SOP Power = DefauIt/Implicit or Explicit Contract PD = Connected PE_SNK_Wait_for_Capabilities Transmission Error indication from Protocol Layer PE_SNK_Ready In Explicit Contract & Protocol Error2 on SOP before first Message in AMS sent (no GoodCRC received) PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. 2) An Unrecognized or Unsupported Message will result in a Not_Supported Message response being generated (see Section 6.3.16 “Not_Supported Message”). 3) See Section 6.4.10.1 “Process to enter EPR Mode” for the conditions when a Soft_Reset Message Shall be sent by the Sink during the EPR Mode entry process. Page 844 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 On entry to the PE_SNK_Send_Soft_Reset state the Policy Engine Shall request the SOP Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP to the Source, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An Accept Message has been received on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  A SenderResponseTimer timeout occurs.  Or the Protocol Layer indicates that a transmission error has occurred. 8.3.3.4.2.2 PE_SNK_Soft_Reset State The PE_SNK_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received on SOP from the Protocol Layer. On entry to the PE_SNK_Soft_Reset state the Policy Engine Shall reset the SOP Protocol Layer and Shall then request the Protocol Layer to send an Accept Message on SOP. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The Accept Message has been sent on SOP. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  The Protocol Layer indicates that a transmission error has occurred. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 845 8.3.3.5 Data Reset State Diagrams 8.3.3.5.1 DFP Data_Reset Message State Diagrams Figure 8.136, "DFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a DFP. Figure 8.136 DFP Data_Reset Message State Diagram 8.3.3.5.1.1 PE_DDR_Send_Data_Reset State The PE_DDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_DDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and start the SenderResponseTimer. On exit from the PE_DDR_Send_Data_Reset State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been received and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been received and PE_DDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and start SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_DDR_Wait_for_VCONN_Off Actions on entry: Initialize and start VCONNDischargeTimer Power = Explicit Contract PD = connected Accept Message Received & Not VCONN Source VCONNDischargeTimer Timeout | Protocol Error PS_RDY Received PE_DDR_Perform_Data_Reset Actions on entry: Tell Device Policy Manager to perform Data Reset Power = Explicit Contract PD = connected PE_SRC_Ready or PE_SNK_Ready (DFP) Data Reset process is complete Accept Message Sent & Not VCONN Source Protocol Error DataResetFailTimer Timeout | Protocol Error Actions on exit: Stop DataResetFailTimer Send Data_Reset_Complete Message Actions on exit: Initialize and start DataResetFailTimer1 Actions on exit: Initialize and start DataResetFailTimer1 1) Note that the DataResetFailTimer Shall continue to run in every state until it is stopped or times out. Page 846 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A SenderResponseTimer timeout occurs or  A Protocol Error occurs. 8.3.3.5.1.2 PE_DDR_Data_Reset_Received State The PE_DDR_Data_Reset_Received State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_DDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_DDR_Data_Reset_Received State the Policy Engine Shall initialize and start the DataResetFailTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  An Accept Message has been sent and  The DFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_DDR_Wait_For_VCONN_Off State when:  An Accept Message has been sent and  The DFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.1.3 PE_DDR_Wait_For_VCONN_Off State On entry to the PE_DDR_Wait_For_VCONN_Off State the Policy Engine Shall initialize and start the VCONNDischargeTimer. The Policy Engine Shall transition to the PE_DDR_Perform_Data_Reset State when:  A PS_RDY Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The VCONNDischargeTimer has timed out or  A Protocol Error occurs. 8.3.3.5.1.4 PE_DDR_Perform_Data_Reset State On entry to the PE_DDR_Perform_Data_Reset State the Policy Engine Shall request the Device Policy Manager to complete the Data Reset process as defined in Section 6.3.14, "Data_Reset Message". On exit from the PE_DDR_Perform_Data_Reset State the Policy Engine Shall stop the DataResetFailTimer and send a Data_Reset_Complete Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the DFP's Power Role when:  The DPM indicates that Data Reset process is complete (see Section 6.3.14, "Data_Reset Message"). The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailTimer times out  A Protocol Error occurs. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 847 8.3.3.5.2 UFP Data_Reset Message State Diagrams Figure 8.137, "UFP Data_Reset Message State Diagram" shows the state diagram for a Data_Reset Message sent or received by a UFP. Figure 8.137 UFP Data_Reset Message State Diagram 8.3.3.5.2.1 PE_UDR_Send_Data_Reset State The PE_UDR_Send_Data_Reset State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager. On entry to the PE_UDR_Send_Data_Reset State the Policy Engine Shall request the Protocol Layer to send a Data_Reset Message and then initialize and run the SenderResponseTimer. On exit from the PE_UDR_Send_Data_Reset State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been received and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been received and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when: PE_UDR_Send_Data_Reset Actions on entry: Send Data_Reset Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Data Reset request from DPM Accept Message Received & VCONN Source PE_SRC_Ready or PE_SNK_Ready (UFP) PE_UDR_Data_Reset_Received Actions on entry: Inform Device Policy Manager of Data_Reset Message Send Accept Message Power = Explicit Contract PD = connected Data_Reset Message received Accept Message Sent & VCONN Source ErrorRecovery SenderResponseTimer Timeout | Protocol Error PE_UDR_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = connected PE_UDR_Send_Ps_Rdy Actions on entry: Send PS_RDY Message Power = Explicit Contract PD = connected VCONN Off1 PE_SRC_Ready or PE_SNK_Ready (UFP) Accept Message Received & Not VCONN Source PS_RDY Message Sent Accept Message Sent & Not VCONN Source Protocol Error PE_UDR_Wait_For_Data_Reset_Complete Actions on entry: Wait for Data_Reset_Complete Message Power = Explicit Contract PD = connected Data_Reset_Complete Message received Protocol Error Protocol Error DataResetFailUFPTimer Timeout2 | Protocol Error Actions on exit: Stop DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 Actions on exit: Initialize and run DataResetFailUFPTimer2 1) VCONN Shall be fully discharged see Section 7.1.15 “Vconn Power Cycle”. 2) Note that the DataResetFailUFPTimer Shall continue to run in every state until it is stopped or times out. Page 848 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The SenderResponseTimer has timed out or  A Protocol Error occurs. 8.3.3.5.2.2 PE_UDR_Data_Reset_Received State The PE_UDR_Data_Reset_Received State Shall be entered from either the PE_SRC_Ready or PE_SNK_Ready State when a Data_Reset Message is received. On entry to the PE_UDR_Data_Reset_Received State the Policy Engine Shall inform the Device Policy Manager and then Shall send an Accept Message. On exit from the PE_UDR_Data_Reset_Received State the Policy Engine Shall initialize and run the DataResetFailUFPTimer. The Policy Engine Shall transition to the PE_UDR_Turn_Off_VCONN State when:  An Accept Message has been sent and  The UFP is presently the VCONN Source. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  An Accept Message has been sent and  The UFP is not presently the VCONN Source. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.3 PE_UDR_Turn_Off_VCONN State On entry to the PE_UDR_Turn_Off_VCONN State the Policy Engine Shall request the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition to the PE_UDR_Send_Ps_Rdy State when:  The DPM indicates that VCONN has been turned off (VCONN below vRaReconnect see [USB Type-C 2.4]). The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.4 PE_UDR_Send_Ps_Rdy State On entry to the PE_UDR_Send_Ps_Rdy State the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_UDR_Wait_For_Data_Reset_Complete State when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to ErrorRecovery when:  A Protocol Error occurs. 8.3.3.5.2.5 PE_UDR_Wait_For_Data_Reset_Complete State On entry to the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall wait for the Data_Reset_Complete Message. On exit from the PE_UDR_Wait_For_Data_Reset_Complete State the Policy Engine Shall stop the DataResetFailUFPTimer. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State depending on the UFP's Power Role when: Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 849  The Data_Reset_Complete Message is received. The Policy Engine Shall transition to ErrorRecovery when:  The DataResetFailUFPTimer times out or  A Protocol Error occurs. Page 850 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6 Not Supported Message State Diagrams 8.3.3.6.1 Source Port Not Supported Message State Diagram Figure 8.138, "Source Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Source Port. Figure 8.138 Source Port Not Supported Message State Diagram 8.3.3.6.1.1 PE_SRC_Send_Not_Supported State The PE_SRC_Send_Not_Supported state Shall be entered from the PE_SRC_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SRC_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SRC_Send_Not_Supported state (from the PE_SRC_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.1.2 PE_SRC_Not_Supported_Received State The PE_SRC_Not_Supported_Received state Shall be entered from the PE_SRC_Ready state when a Not_Supported Message is received. On entry to the PE_SRC_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SRC_Ready see Figure 8.132, "Source Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.1.3 PE_SRC_Chunk_Received State The PE_SRC_Chunk_Received state Shall be entered from the PE_SRC_Ready state as a result of an Unsupported Message being received in the PE_SRC_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). PE_SRC_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SRC_Ready PE_SRC_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SRC_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SRC_Ready state directly (see also Section 8.3.3.4.1 “SOP Source Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 851 On entry to the PE_SRC_Chunk_Received state (from the PE_SRC_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SRC_Send_Not_Supported when:  The ChunkingNotSupportedTimer has timed out. Page 852 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.6.2 Sink Port Not Supported Message State Diagram Figure 8.139, "Sink Port Not Supported Message State Diagram" shows the state diagram for a Not_Supported Message sent or received by a Sink Port. Figure 8.139 Sink Port Not Supported Message State Diagram 8.3.3.6.2.1 PE_SNK_Send_Not_Supported State The PE_SNK_Send_Not_Supported state Shall be entered from the PE_SNK_Ready state either as the result of a Protocol Error received during an interruptible AMS or as a result of an Unsupported Message being received in the PE_SNK_Ready state directly except for the first Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Send_Not_Supported state (from the PE_SNK_Ready state) the Policy Engine Shall request the Protocol Layer to send a Not_Supported Message. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Not_Supported Message has been successfully sent. 8.3.3.6.2.2 PE_SNK_Not_Supported_Received State The PE_SNK_Not_Supported_Received state Shall be entered from the PE_SNK_Ready state when a Not_Supported Message is received. On entry to the PE_SNK_Not_Supported_Received state the Policy Engine Shall inform the Device Policy Manager. The Policy Engine Shall transition back to the previous state (PE_SNK_Ready see Figure 8.133, "Sink Port State Diagram") when:  The Device Policy Manager has been informed. 8.3.3.6.2.3 PE_SNK_Chunk_Received State The PE_SNK_Chunk_Received state Shall be entered from the PE_SNK_Ready state as a result of an Unsupported Message being received in the PE_SNK_Ready state directly where the Message is a Chunk in a multi-Chunk Message (see also Section 6.12.2.1, "Protocol Layer Chunking" and Section 8.3.3.4.1, "SOP Source Port Soft Reset and Protocol Error State Diagram"). On entry to the PE_SNK_Chunk_Received state (from the PE_SNK_Ready state) the Policy Engine Shall initialize and run the ChunkingNotSupportedTimer. The Policy Engine Shall transition to PE_SNK_Send_Not_Supported when: PE_SNK_Send_Not_Supported Actions on entry: Send Not_Supported Message Power = Explicit Contract PD = connected Protocol Error1 & not a Chunk from a multi-Chunk Message Not_Supported Message sent PE_SNK_Ready PE_SNK_Not_Supported_Received Actions on entry: Inform Device Policy Manager of Not_Supported Message Power = Explicit Contract PD = connected Not_Supported Message received1 DPM informed PE_SNK_Chunk_Received Actions on entry: Start ChunkingNotSupportedTimer Power = Explicit Contract PD = connected Protocol Error1 & Chunk from a multi-Chunk Message2 ChunkingNotSupportedTimer timeout 1) Transition as a result of an unsupported Message being received in the PE_SNK_Ready state directly (see also Section 8.3.3.4.2 “SOP Sink Port Soft Reset and Protocol Error State Diagram”). 2) Transition can only occur where a manufacturer has opted not to implement a Chunking state machine (see Section 6.12.2.1 “Protocol Layer Chunking”) and is communicating with a system which is attempting to send it Chunks. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 853  The ChunkingNotSupportedTimer has timed out. Page 854 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7 Alert State Diagrams 8.3.3.7.1 Source Port Source Alert State Diagram Figure 8.140, "Source Port Source Alert State Diagram" shows the state diagram for an Alert Message sent by a Source Port. Figure 8.140 Source Port Source Alert State Diagram 8.3.3.7.1.1 PE_SRC_Send_Source_Alert State The PE_SRC_Send_Source_Alert state Shall be entered from the PE_SRC_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SRC_Send_Source_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SRC_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.1.2 PE_SRC_Wait_for_Get_Status State On entry to the PE_SRC_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The SenderResponseTimer times out. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 855 8.3.3.7.2 Sink Port Source Alert State Diagram Figure 8.141, "Sink Port Source Alert State Diagram" shows the state diagram for an Alert Message received by a Sink Port. Figure 8.141 Sink Port Source Alert State Diagram 8.3.3.7.2.1 PE_SNK_Source_Alert_Received State The PE_SNK_Source_Alert_Received state Shall be entered from the PE_SNK_Ready state when an Alert Message is received. On entry to the PE_SNK_Source_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SNK_Ready State (see Figure 8.133, "Sink Port State Diagram") when:  The DPM does not request status. PE_SRC_Send_Source_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Source alert condition Alert Message sent PE_SRC_Ready SenderResponseTimer Timeout PE_SRC_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Page 856 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.7.3 Sink Port Sink Alert State Diagram Figure 8.142, "Sink Port Sink Alert State Diagram" shows the state diagram for an Alert Message sent by a Sink Port. Figure 8.142 Sink Port Sink Alert State Diagram 8.3.3.7.3.1 PE_SNK_Send_Sink_Alert State The PE_SNK_Send_Sink_Alert state Shall be entered from the PE_SNK_Ready state when the Device Policy Manager indicates that there is a Source alert condition to be reported. On entry to the PE_SNK_Send_Sink_Alert state the Policy Engine Shall request the Protocol Layer to send an Alert Message. The Policy Engine Shall transition to the PE_SNK_Wait_for_Get_Status State when:  The Alert Message has been successfully sent. 8.3.3.7.3.2 PE_SNK_Wait_for_Get_Status State On entry to the PE_SNK_Wait_for_Get_Status State the Policy Engine Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition back to the PE_Give_Status State (see Figure 8.151, "Give Status State Diagram") when:  A Get_Status Message is received. The Policy Engine Shall transition back to the PE_SNK_Ready (see Figure 8.133, "Sink Port State Diagram") when:  The SenderResponseTimer times out. PE_SNK_Send_Sink_Alert Actions on entry: Send Alert Message Power = Explicit Contract PD = connected DPM indicates Sink alert condition Alert Message sent PE_SNK_Ready SenderResponseTimer Timeout PE_SNK_Wait_for_Get_Status Actions on entry: Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected PE_Give_Status Get_Status Message received Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 857 8.3.3.7.4 Source Port Sink Alert State Diagram Figure 8.143, "Source Port Sink Alert State Diagram" shows the state diagram for an Alert Message received by a Source Port. Figure 8.143 Source Port Sink Alert State Diagram 8.3.3.7.4.1 PE_SRC_Sink_Alert_Received State The PE_SRC_Sink_Alert_Received state Shall be entered from the PE_SRC_Ready state when an Alert Message is received. On entry to the PE_SRC_Sink_Alert_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the Source alert. The Policy Engine Shall transition to the PE_Get_Status State (see Figure 8.150, "Get Status State Diagram") when:  The DPM requests status. The Policy Engine Shall transition back to the PE_SRC_Ready (see Figure 8.132, "Source Port State Diagram") when:  The DPM does not request status. PE_SRC_Sink_Alert_Received Actions on entry: Inform DPM of the detail of the alert Power = Explicit Contract PD = connected Sink Alert Message received DPM does not request status PE_SRC_Ready PE_Get_Status DPM Requests Status Page 858 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8 Source/Sink Capabilities Extended State Diagrams 8.3.3.8.1 Sink Port Get Source Capabilities Extended State Diagram Figure 8.144, "Sink Port Get Source Capabilities Extended State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.144 Sink Port Get Source Capabilities Extended State Diagram 8.3.3.8.1.1 PE_SNK_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Get_Source_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 859 8.3.3.8.2 Source Give Source Capabilities Extended State Diagram Figure 8.145, "Source Give Source Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.145 Source Give Source Capabilities Extended State Diagram 8.3.3.8.2.1 PE_SRC_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Give_Source_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_SRC_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SRC_Ready PE_SRC_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 860 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.8.3 Source Port Get Sink Capabilities Extended State Diagram Figure 8.146, "Source Port Get Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.146 Source Port Get Sink Capabilities Extended State Diagram 8.3.3.8.3.1 PE_SRC_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SRC_Get_Sink_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Sink_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_SRC_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass sink extended capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 861 8.3.3.8.4 Sink Give Sink Capabilities Extended State Diagram Figure 8.147, "Sink Give Sink Capabilities Extended State Diagram" shows the state diagram for a Source on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.147 Sink Give Sink Capabilities Extended State Diagram 8.3.3.8.4.1 PE_SNK_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_SNK_Give_Sink_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_SNK_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Sink_Capabilities_Extended Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SNK_Ready PE_SNK_Give_Sink_Cap_Ext Actions on entry: Get present extended Sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 862 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.9 Source Information State Diagrams 8.3.3.9.1 Sink Port Get Source Information State Diagram Figure 8.148, "Sink Port Get Source Information State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.148 Sink Port Get Source Information State Diagram 8.3.3.9.1.1 PE_SNK_Get_Source_Info State The Policy Engine Shall transition to the PE_SNK_Get_Source_Info state, from the PE_SNK_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_SNK_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Source_Info Message is received  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 863 8.3.3.9.2 Source Give Source Information State Diagram Figure 8.149, "Source Give Source Information State Diagram" shows the state diagram for a Source on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.149 Source Give Source Information State Diagram 8.3.3.9.2.1 PE_SRC_Give_Source_Info State The Policy Engine Shall transition to the PE_SRC_Give_Source_Info state, from the PE_SRC_Ready state, when a Get_Source_Info Message is received. On entry to the PE_SRC_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SRC_Ready PE_SRC_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 864 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10 Status State Diagrams 8.3.3.10.1 Get Status State Diagram Figure 8.150, "Get Status State Diagram" shows the state diagram for a Port on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Status. See also Section 6.5.2, "Status Message". Figure 8.150 Get Status State Diagram 8.3.3.10.1.1 PE_Get_Status State The Policy Engine Shall transition to the PE_Get_Status state, from the PE_SRC_Ready or PE_SNK_Ready States, due to a request to get the Port Partner or Cable Plug's status from the Device Policy Manager. On entry to the PE_Get_Status state the Policy Engine Shall send a Get_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram" or Figure 8.133, "Sink Port State Diagram") when:  A Status Message is received  Or SenderResponseTimer times out. get status request from Device Policy Manager Status Message received | SenderResponseTimer Timeout PE_SNK_Ready, PE_SRC_Ready PE_Get_Status Actions on entry: Send Get_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 865 8.3.3.10.2 Give Status State Diagram Figure 8.151, "Give Status State Diagram" shows the state diagram for a Source on receiving a Get_Status Message. See also Section 6.5.2, "Status Message". Figure 8.151 Give Status State Diagram 8.3.3.10.2.1 PE_Give_Status State The Policy Engine Shall transition to the PE_Give_Status state, from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States, when a Get_Status Message is received. On entry to the PE_Give_Status state the Policy Engine Shall request the present Source status from the Device Policy Manager and then send a Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready States as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram"and Figure 8.203, "Cable Ready State Diagram") when:  The Status Message has been successfully sent. Get_Status Message received Status Message sent PE_SRC_Ready, PE_SNK_Ready, PE_CBL_Ready PE_Give_Status Actions on entry: Get present Status from Device Policy Manager Send Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 866 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.10.3 Sink Port Get Source PPS Status State Diagram Figure 8.152, "Sink Port Get Source PPS Status State Diagram" shows the state diagram for a Sink on receiving a request from the Device Policy Manager to get the Port Partner's Source status when operating as a PPS. See also Section 6.5.10, "PPS_Status Message". Figure 8.152 Sink Port Get Source PPS Status State Diagram 8.3.3.10.3.1 PE_SNK_Get_PPS_Status State The Policy Engine Shall transition to the PE_SNK_Get_PPS_Status state, from the PE_SNK_Ready state, due to a request to get the remote Source PPS status from the Device Policy Manager. On entry to the PE_SNK_Get_PPS_Status state the Policy Engine Shall send a Get_PPS_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_SNK_Get_PPS_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A PPS_Status Message is received  Or SenderResponseTimer times out. get PPS status request from Device Policy Manager PPS_Status Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_SNK_Get_PPS_Status Actions on entry: Send Get_PPS_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Source status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 867 8.3.3.10.4 Source Give Source PPS Status State Diagram Figure 8.153, "Source Give Source PPS Status State Diagram" shows the state diagram for a Source on receiving a Get_PPS_Status Message. See also Section 6.5.10, "PPS_Status Message". Figure 8.153 Source Give Source PPS Status State Diagram 8.3.3.10.4.1 PE_SRC_Give_PPS_Status State The Policy Engine Shall transition to the PE_SRC_Give_PPS_Status state, from the PE_SRC_Ready state, when a Get_PPS_Status Message is received. On entry to the PE_SRC_Give_PPS_Status state the Policy Engine Shall request the present Source PPS status from the Device Policy Manager and then send a PPS_Status Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The PPS_Status Message has been successfully sent. Get_PPS_Status Message received PPS_Status Message sent PE_SRC_Ready PE_SRC_Give_PPS_Status Actions on entry: Get present Source PPS status from Device Policy Manager Send PPS_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 868 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.11 Battery Capabilities State Diagrams 8.3.3.11.1 Get Battery Capabilities State Diagram Figure 8.154, "Get Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery capabilities for a specified Battery. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.154 Get Battery Capabilities State Diagram 8.3.3.11.1.1 PE_Get_Battery_Cap State The Policy Engine Shall transition to the PE_Get_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery capabilities, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Cap state the Policy Engine Shall send a Get_Battery_Cap Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Capabilities Message is received  Or SenderResponseTimer times out. get Battery capabilities request from Device Policy Manager Battery_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Cap Actions on entry: Send Get_Battery_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery capabilities/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 869 8.3.3.11.2 Give Battery Capabilities State Diagram Figure 8.155, "Give Battery Capabilities State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Cap Message. See also Section 6.5.5, "Battery_Capabilities Message". Figure 8.155 Give Battery Capabilities State Diagram 8.3.3.11.2.1 PE_Give_Battery_Cap State The Policy Engine Shall transition to the PE_Give_Battery_Cap state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Cap Message is received. On entry to the PE_Give_Battery_Cap state the Policy Engine Shall request the present Battery capabilities, for the requested Battery, from the Device Policy Manager and then send a Battery_Capabilities Message based on these capabilities. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Capabilities Message has been successfully sent. Get_Battery_Cap Message received Battery_Capabilities Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Cap Actions on entry: Get present Battery capabilities from Device Policy Manager Send Battery_Capabilities Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 870 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.12 Battery Status State Diagrams 8.3.3.12.1 Get Battery Status State Diagram Figure 8.156, "Get Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner's Battery status for a specified Battery. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.156 Get Battery Status State Diagram 8.3.3.12.1.1 PE_Get_Battery_Status State The Policy Engine Shall transition to the PE_Get_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Battery status, for a specified Battery, from the Device Policy Manager. On entry to the PE_Get_Battery_Status state the Policy Engine Shall send a Get_Battery_Status Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Battery_Status state the Policy Engine Shall inform the Device Policy Manager of the outcome (status or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Battery_Status Message is received  Or SenderResponseTimer times out. get Battery status request from Device Policy Manager Battery_Status Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Battery_Status Actions on entry: Send Get_Battery_Status Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Battery status/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 871 8.3.3.12.2 Give Battery Status State Diagram Figure 8.157, "Give Battery Status State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Battery_Status Message. See also Section 6.5.4, "Get_Battery_Status Message". Figure 8.157 Give Battery Status State Diagram 8.3.3.12.2.1 PE_Give_Battery_Status State The Policy Engine Shall transition to the PE_Give_Battery_Status state, from either the PE_SRC_Ready or PE_SNK_Ready state, when a Get_Battery_Status Message is received. On entry to the PE_Give_Battery_Status state the Policy Engine Shall request the present Battery status, for the requested Battery, from the Device Policy Manager and then send a Battery_Status Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Battery_Status Message has been successfully sent. Get_Battery_Status Message received Battery_Status Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Battery_Status Actions on entry: Get present Battery status from Device Policy Manager Send Battery_Status Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 872 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.13 Manufacturer Information State Diagrams 8.3.3.13.1 Get Manufacturer Information State Diagram Figure 8.158, "Get Manufacturer Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Manufacturer Information. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.158 Get Manufacturer Information State Diagram 8.3.3.13.1.1 PE_Get_Manufacturer_Info State The Policy Engine Shall transition to the PE_Get_Manufacturer_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Manufacturer_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Manufacturer_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Manufacturer_Info Message is received  Or SenderResponseTimer times out. get manufacturer information request from Device Policy Manager Manufacturer_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Manfacturer_Info Actions on entry: Send Get_Manfacturer_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Manufacturer Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 873 8.3.3.13.2 Give Manufacturer Information State Diagram Figure 8.159, "Give Manufacturer Information State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Manufacturer_Info Message. See also Section 6.5.6, "Get_Manufacturer_Info Message". Figure 8.159 Give Manufacturer Information State Diagram 8.3.3.13.2.1 PE_Give_Manufacturer_Info State The Policy Engine Shall transition to the PE_Give_Manufacturer_Info state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Manufacturer_Info Message is received. On entry to the PE_Give_Manufacturer_Info state the Policy Engine Shall request the manufacturer information from the Device Policy Manager and then send a Manufacturer_Info Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Manufacturer_Info Message has been successfully sent. Get_Manufacturer_Info Message received Manufacturer_Info Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Manufacturer_Info Actions on entry: Get present Manufacturer Information from Device Policy Manager Send Manufacturer_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 874 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14 Country Codes and Information State Diagrams 8.3.3.14.1 Get Country Codes State Diagram Figure 8.160, "Get Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Codes. See also Section 6.5.11, "Country_Codes Message". Figure 8.160 Get Country Codes State Diagram 8.3.3.14.1.1 PE_Get_Country_Codes State The Policy Engine Shall transition to the PE_Get_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Country Codes from the Device Policy Manager. On entry to the PE_Get_Country_Codes state the Policy Engine Shall send a Get_Country_Codes Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Codes state the Policy Engine Shall inform the Device Policy Manager of the outcome (Country Codes or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Codes Message is received  Or SenderResponseTimer times out. get country codes request from Device Policy Manager Country_Codes Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Codes Actions on entry: Send Get_Country_Codes Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Codes/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 875 8.3.3.14.2 Give Country Codes State Diagram Figure 8.161, "Give Country Codes State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Codes Message. See also Section 6.5.11, "Country_Codes Message". Figure 8.161 Give Country Codes State Diagram 8.3.3.14.2.1 PE_Give_Country_Codes State The Policy Engine Shall transition to the PE_Give_Country_Codes state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Codes Message is received. On entry to the PE_Give_Country_Codes state the Policy Engine Shall request the country codes from the Device Policy Manager and then send a Country_Codes Message containing these codes. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Codes Message has been successfully sent. Get_Country_Codes Message received Country_Codes Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Codes Actions on entry: Get present Country Codes from Device Policy Manager Send Country_Codes Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 876 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.14.3 Get Country Information State Diagram Figure 8.162, "Get Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Country Information. See also Section 6.5.12, "Country_Info Message". Figure 8.162 Get Country Information State Diagram 8.3.3.14.3.1 PE_Get_Country_Info State The Policy Engine Shall transition to the PE_Get_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Manufacturer Information from the Device Policy Manager. On entry to the PE_Get_Country_Info state the Policy Engine Shall send a Get_Manufacturer_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Country_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (country information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Country_Info Message is received  Or SenderResponseTimer times out. get country information request from Device Policy Manager Country_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Country_Info Actions on entry: Send Get_Country_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Country Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 877 8.3.3.14.4 Give Country Information State Diagram Figure 8.163, "Give Country Information State Diagram" shows the state diagram for a Source or Sink on receiving a Get_Country_Info Message. See also Section 6.5.12, "Country_Info Message". Figure 8.163 Give Country Information State Diagram 8.3.3.14.4.1 PE_Give_Country_Info State The Policy Engine Shall transition to the PE_Give_Country_Info state, from either the PE_SRC_Ready or PE_SNK_Ready State, when a Get_Country_Info Message is received. On entry to the PE_Give_Country_Info state the Policy Engine Shall request the country information from the Device Policy Manager and then send a Country_Info Message containing this country information. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready State as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Country_Info Message has been successfully sent. Get_Country_Info Message received Country_Info Message sent PE_SRC_Ready or PE_SNK_Ready PE_Give_Country_Info Actions on entry: Get present Country Information from Device Policy Manager Send Country_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 878 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.15 Revision State Diagrams 8.3.3.15.1 Get Revision State Diagram Figure 8.164, "Get Revision State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to get the Port Partner or Cable Plug's Revision Information. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.164 Get Revision State Diagram 8.3.3.15.1.1 PE_Get_Revision State The Policy Engine Shall transition to the PE_Get_Revision state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to get the remote Revision Information from the Device Policy Manager. On entry to the PE_Get_Revision state the Policy Engine Shall send a Get_Revision Message and initialize and run the SenderResponseTimer. On exit from the PE_Get_Revision state the Policy Engine Shall inform the Device Policy Manager of the outcome (Revision information or response timeout). The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  A Revision Message is received  Or SenderResponseTimer times out. get Revision request from Device Policy Manager Revision Message received | SenderResponseTimer Timeout PE_SRC_Ready or PE_SNK_Ready PE_Get_Revision Actions on entry: Send Get_Revision Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Revision Information/outcome to Device Policy Manager Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 879 8.3.3.15.2 Give Revision State Diagram Figure 8.165, "Give Revision State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Get_Revision Message. See also Section 6.3.24, "Get_Revision Message" and Section 6.4.12, "Revision Message". Figure 8.165 Give Revision State Diagram 8.3.3.15.2.1 PE_Give_Revision State The Policy Engine Shall transition to the PE_Give_Revision state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Get_Revision Message is received. On entry to the PE_Give_Revision state the Policy Engine Shall request the Revision information from the Device Policy Manager and then send a Revision Message based on this information. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Revision Message has been successfully sent. Get_Revision Message received Revision Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Give_Revision Actions on entry: Get present Revision Information from Device Policy Manager Send Revision Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 880 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.16 Enter_USB Message State Diagrams 8.3.3.16.1 DFP Enter_USB Message State Diagrams Figure 8.166, "DFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message sent by a DFP. Figure 8.166 DFP Enter_USB Message State Diagram 8.3.3.16.1.1 PE_DEU_Send_Enter_USB State The PE_DEU_Send_Enter_USB State Shall be entered from the PE_SRC_Ready or PE_SNK_Ready State when requested by the Device Policy Manager and the Port is operating as a DFP. On entry to the PE_DEU_Send_Enter_USB State the Policy Engine Shall request the Protocol Layer to send an Enter_USB Message and then initialize and run the SenderResponseTimer. On exit from the PE_DEU_Send_Enter_USB state the Policy Engine Shall inform the Device Policy Manager of the outcome: Accept Message received, Reject Message received, SenderResponseTimer timeout. The Policy Engine Shall transition back to the PE_SRC_Ready or PE_SNK_Ready State depending on the Ports Power Role when:  An Accept Message has been received or  A Wait Message has been received or  A Reject Message has been received  There is a SenderResponseTimer timeout. PE_DEU_Send_Enter_USB Actions on entry: Send Enter_USB Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = connected Enter USB (USB Mode) request from DPM Accept Message Received | Reject Message Received | Wait Message Received | SenderResponseTimer timeout PE_SRC_Ready or PE_SNK_Ready (DFP) Actions on exit: Inform Device Policy Manager of Accept, Wait, Reject or timeout. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 881 8.3.3.16.2 UFP or Cable Plug Enter_USB Message State Diagrams Figure 8.167, "UFP Enter_USB Message State Diagram" shows the state diagram for an Enter_USB Message received by a UFP or Cable Plug. Figure 8.167 UFP Enter_USB Message State Diagram 8.3.3.16.2.1 PE_UEU_Enter_USB_Received State The PE_UEU_Enter_USB_Received state Shall be entered from the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when an Enter_USB Message is received and the Port is operating as a UFP or is a Cable Plug. On entry to the PE_UEU_Enter_USB_Received state the Policy Engine Shall inform the Device Policy Manager. The Device Policy Manager responds with an indication of whether the Enter_USB Message is to be accepted or rejected. The Policy Engine Shall send either an Accept Message, a Wait Message or a Reject Message as appropriate. The Policy Engine Shall transition back to the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate when:  Either an Accept Message, a Wait Message or a Reject Message has been sent. PE_SRC_Ready (UFP), PE_SNK_Ready (UFP) or PE_CBL_Ready PE_UEU_Enter_USB_Received Actions on entry: Inform Device Policy Manager of Enter_USB Message Send Accept/Wait/Reject Message based on DPM response Power = Explicit Contract PD = connected Enter_USB Message Received Accept/Wait/Reject Message sent Page 882 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17 Security State Diagrams 8.3.3.17.1 Send Security Request State Diagram Figure 8.168, "Send security request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a security request. See also Section 6.5.8, "Security Messages". Figure 8.168 Send security request State Diagram 8.3.3.17.1.1 PE_Send_Security_Request State The Policy Engine Shall transition to the PE_Send_Security_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a security request from the Device Policy Manager. On entry to the PE_Send_Security_Request state the Policy Engine Shall send a Security_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Security_Request Message has been sent. Send security request from Device Policy Manager Security_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Security_Request Actions on entry: Send Security_Request Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 883 8.3.3.17.2 Send Security Response State Diagram Figure 8.169, "Send security response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Security_Request Message. See also Section 6.5.8, "Security Messages". Figure 8.169 Send security response State Diagram 8.3.3.17.2.1 PE_Send_Security_Response State The Policy Engine Shall transition to the PE_Send_Security_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Security_Request Message is received. On entry to the PE_Send_Security_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Security_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Security_Response Message has been successfully sent. Security_Request Message received Security_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Security_Response Actions on entry: Get present Security response from Device Policy Manager Send Security_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Page 884 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.17.3 Security Response Received State Diagram Figure 8.170, "Security response received State Diagram" shows the state diagram for a Source or Sink on receiving a Security_Response Message. See also Section 6.5.8, "Security Messages". Figure 8.170 Security response received State Diagram 8.3.3.17.3.1 PE_Security_Response_Received State The Policy Engine Shall transition to the PE_Security_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Security_Response Message is received. On entry to the PE_Security_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the security response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Security_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Security_Response_Received Actions on entry: Inform Device Policy Manager of the security response details. Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 885 8.3.3.18 Firmware Update State Diagrams 8.3.3.18.1 Send Firmware Update Request State Diagram Figure 8.171, "Send firmware update request State Diagram" shows the state diagram for a Source or Sink on receiving a request from the Device Policy Manager to send a firmware update request. See also Section 6.5.9, "Firmware Update Messages". Figure 8.171 Send firmware update request State Diagram 8.3.3.18.1.1 PE_Send_Firmware_Update_Request State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Request state, from either the PE_SRC_Ready or PE_SNK_Ready state, due to a request to send a firmware update request from the Device Policy Manager. On entry to the PE_Send_Firmware_Update_Request state the Policy Engine Shall send a Firmware_Update_Request Message. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram" and Figure 8.133, "Sink Port State Diagram") when:  The Firmware_Update_Request Message has been sent. Send firmware update request from Device Policy Manager Firmware_Update_Request Message sent PE_SRC_Ready or PE_SNK_Ready PE_Send_Firmware_Update_Request Actions on entry: Send Firmware_Update_Request Message Power = Explicit Contract PD = Connected Page 886 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.18.2 Send Firmware Update Response State Diagram Figure 8.172, "Send firmware update response State Diagram" shows the state diagram for a Source, Sink or Cable Plug on receiving a Firmware_Update_Request Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.172 Send firmware update response State Diagram 8.3.3.18.2.1 PE_Send_Firmware_Update_Response State The Policy Engine Shall transition to the PE_Send_Firmware_Update_Response state, from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state, when a Firmware_Update_Request Message is received. On entry to the PE_Send_Firmware_Update_Response state the Policy Engine Shall request the appropriate response from the Device Policy Manager and then send a Firmware_Update_Response Message based on this status. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Firmware_Update_Response Message has been successfully sent. Firmware_Update_Request Message received Firmware_Update_Response Message sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready PE_Send_Firmware_Update_Response Actions on entry: Get present firmware update response from Device Policy Manager Send Firmware_Update_Response Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 887 8.3.3.18.3 Firmware Update Response Received State Diagram Figure 8.173, "Firmware update response received State Diagram" shows the state diagram for a Source or Sink on receiving a Firmware_Update_Response Message. See also Section 6.5.9, "Firmware Update Messages". Figure 8.173 Firmware update response received State Diagram 8.3.3.18.3.1 PE_Firmware_Update_Response_Received State The Policy Engine Shall transition to the PE_Firmware_Update_Response_Received state, from either the PE_SRC_Ready or PE_SNK_Ready when a Firmware_Update_Response Message is received. On entry to the PE_Firmware_Update_Response_Received state the Policy Engine Shall inform the Device Policy Manager of the details of the firmware update response. The Policy Engine Shall transition back to either the PE_SRC_Ready or PE_SNK_Ready state as appropriate (see Figure 8.132, "Source Port State Diagram", Figure 8.133, "Sink Port State Diagram" and Figure 8.203, "Cable Ready State Diagram") when:  The Device Policy Manager has been informed. Firmware_Update_Response Message received DPM informed PE_SRC_Ready or PE_SNK_Ready PE_Firmware_Update_Response_Received Actions on entry: Inform Device Policy Manager of the firmware update response details. Power = Explicit Contract PD = Connected Page 888 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19 Dual-Role Port State Diagrams Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition they Shall have the capability to perform a Power Role Swap from the PE_SRC_Ready or PE_SNK_Ready states and Shall return to USB Default Operation on a Hard Reset. The State Diagrams in this section Shall apply to every [USB Type-C 2.4] DRP. 8.3.3.19.1 DFP to UFP Data Role Swap State Diagram Figure 8.174, "DFP to UFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DFP to UFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.174 DFP to UFP Data Role Swap State Diagram 8.3.3.19.1.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Evaluate_Swap state when:  A DR_Swap Message is received and PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DRS_DFP_UFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_DFP_UFP_ Change_to_UFP Actions on entry: Request Device Policy Manager to change port to UFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_DFP_UFP_ Send_Swap Actions on entry: Send Swap DR message Initialize and run SenderResponseTimer Reject message received | Wait message received | SenderResponseTimer timeout PE_DRS_DFP_UFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_DFP_UFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept message sent Port changed to UFP PE_SRC_Ready or PE_SNK_Ready (UFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap message received & in Modal Operation Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 889  There are no Active Modes (not in Modal Operation). The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.1.2 PE_DRS_DFP_UFP_Evaluate_Swap State On entry to the PE_DRS_DFP_UFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.1.3 PE_DRS_DFP_UFP_Accept_Swap State On entry to the PE_DRS_DFP_UFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  The Accept Message has been sent. 8.3.3.19.1.4 PE_DRS_DFP_UFP_Change_to_UFP State On entry to the PE_DRS_DFP_UFP_Change_to_UFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a DFP to a UFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a UFP. 8.3.3.19.1.5 PE_DRS_DFP_UFP_Send_Swap State On entry to the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_DFP_UFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_DFP_UFP_Change_to_UFP state when:  An Accept Message is received. 8.3.3.19.1.6 PE_DRS_DFP_UFP_Reject_Swap State On entry to the PE_DRS_DFP_UFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send: Page 890 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Reject Message if the device is unable to perform a Data Role Swap at this time.  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a DFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 891 8.3.3.19.2 UFP to DFP Data Role Swap State Diagram Figure 8.175, "UFP to DFP Data Role Swap State Diagram" shows the additional state diagram required to perform a Data Role Swap from DRP UFP to DFP operation and the changes that Shall be followed for error and Hard Reset handling. Figure 8.175 UFP to DFP Data Role Swap State Diagram 8.3.3.19.2.1 PE_SRC_Ready or PE_SNK_Ready State The Data Role Swap process Shall start only from the either the PE_SRC_Ready or PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Evaluate_Swap state when:  A DR_Swap Message is received and  There are no Active Modes (not in Modal Operation). PE_SRC_Ready or PE_SNK_Ready (UFP) PE_DRS_UFP_DFP_Evaluate_Swap Actions on entry: Get evaluation of Data Role Swap request from Device Policy Manager PE_DRS_UFP_DFP_ Change_to_DFP Actions on entry: Request Device Policy Manager to change port to DFP Data Role Swap required (indication from Device Policy Manager) PE_DRS_UFP_DFP_ Send_Swap Actions on entry: Send Swap DR Message Initialize and run SenderResponseTimer Reject Message received | Wait Message received | SenderResponseTimer timeout PE_DRS_UFP_DFP_ Accept_Swap Actions on entry: Send Accept Message Accept received PE_DRS_UFP_DFP_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent DR_Swap Message received & not in Modal Operation Data Role Swap ok Data Role Swap not ok | Further evaluation required Accept Message sent Port changed to DFP PE_SRC_Ready or PE_SNK_Ready (DFP) Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_SRC_Hard_Reset or PE_SNK_Hard_Reset DR_Swap Message received & in Modal Operation Page 892 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset states when:  A DR_Swap Message is received and  There are one or more Active Modes (Modal Operation). The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Send_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is required. 8.3.3.19.2.2 PE_DRS_UFP_DFP_Evaluate_Swap State On entry to the PE_DRS_UFP_DFP_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Data Role Swap can be made. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Accept_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is OK. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Reject_Swap state when:  The Device Policy Manager indicates that a Data Role Swap is not OK.  Or further evaluation of the Data Role Swap request is needed. 8.3.3.19.2.3 PE_DRS_UFP_DFP_Accept_Swap State On entry to the PE_DRS_UFP_DFP_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  The Accept Message has been sent. 8.3.3.19.2.4 PE_DRS_UFP_DFP_Change_to_DFP State On entry to the PE_DRS_UFP_DFP_Change_to_DFP state the Policy Engine Shall request the Device Policy Manager to change the Port from a UFP to a DFP. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager indicates that the Port has been changed to a DFP. 8.3.3.19.2.5 PE_DRS_UFP_DFP_Send_Swap State On entry to the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a DR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_DRS_UFP_DFP_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall continue as a UFP and Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_DRS_UFP_DFP_Change_to_DFP state when:  An Accept Message is received. 8.3.3.19.2.6 PE_DRS_UFP_DFP_Reject_Swap State On entry to the PE_DRS_UFP_DFP_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Data Role Swap at this time. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 893  A Wait Message if further evaluation of the Data Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a DR_Swap Message at a later time (see Section 6.3.12.3, "Wait in response to a DR_Swap Message"). The Policy Engine Shall continue as a UFP and Shall transition to the either the PE_SRC_Ready or PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Page 894 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.3 Policy Engine in Source to Sink Power Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.176, "Dual-Role Port in Source to Sink Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Figure 8.176 Dual-Role Port in Source to Sink Power Role Swap State Diagram PE_SRC_Ready PE_PRS_SRC_SNK_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SRC_SNK_ Transition_to_off Actions on entry: Tell Device Policy Manager to turn off power supply Power = Transition to stop sourcing PD = Connected PE_PRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Source off PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SRC_SNK_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected Accept received PE_PRS_SRC_SNK_ Reject_PR_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PS_RDY Message received PE_SNK_Startup PE_PRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Source off PD = Connected Source turned off Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 895 8.3.3.19.3.1 PE_SRC_Ready State The Power Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Evaluate_Swap state when:  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.3.2 PE_PRS_SRC_SNK_Evaluate_Swap State On entry to the PE_PRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK.  Or further evaluation of the Power Role Swap request is needed. 8.3.3.19.3.3 PE_PRS_SRC_SNK_Accept_Swap State On entry to the PE_PRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.3.4 PE_PRS_SRC_SNK_Transition_to_off State On entry to the PE_PRS_SRC_SNK_Transition_to_off state the Policy Engine Shall request the Device Policy Manager to turn off the Source. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that the Source has been turned off. 8.3.3.19.3.5 PE_PRS_SRC_SNK_Assert_Rd State On entry to the PE_PRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.3.6 PE_PRS_SRC_SNK_Wait_Source_on State On entry to the PE_PRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the remote Source is now supplying power. The Policy Engine Shall transition to the ErrorRecovery state when: Page 896 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.3.7 PE_PRS_SRC_SNK_Send_Swap State On entry to the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall start the SenderResponseTimer. On exit from the PE_PRS_SRC_SNK_Send_Swap state the Policy Engine Shall stop the SenderResponseTimer. The Policy Engine Shall transition to the PE_SRC_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SRC_SNK_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.3.8 PE_PRS_SRC_SNK_Reject_Swap State On entry to the PE_PRS_SRC_SNK_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SRC_Ready when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 897 8.3.3.19.4 Policy Engine in Sink to Source Power Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Shall have the capability to do a Power Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.177, "Dual-role Port in Sink to Source Power Role Swap State Diagram" shows the additional state diagram required to perform a Power Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 898 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.177 Dual-role Port in Sink to Source Power Role Swap State Diagram 8.3.3.19.4.1 PE_SNK_Ready State The Power Role Swap process Shall start only from the PE_SNK_Ready state where power is stable. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Evaluate_Swap state when: PE_SNK_Ready PE_PRS_SNK_SRC_ Evaluate_Swap Actions on entry: Get evaluation of swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_PRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Tell Device Policy Manager to turn off Power Sink. Power = Transition to stop sinking PD = Connected Power Role Swap required (indication from Device Policy Manager) PE_PRS_SNK_SRC_ Send_Swap Actions on entry: Send PR_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout PE_PRS_SNK_SRC_Accept_Swap Actions on entry: Send Accept Message Disable Fast Role Swap Receiver if enabled Power = Explicit Contract PD = Connected Accept Message received PE_PRS_SNK_SRC_ Reject_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected PR_Swap Message received Power Role Swap ok Power Role Swap not ok | Further evaluation required Accept Message sent PE_PRS_SNK_SRC_ Source_on Actions on entry: Tell Device Policy Manager to turn on Source Power = Transition to source on PD = Connected VBUS is at vSafe5V Actions on exit: Send PS_RDY Message PE_SRC_Startup Message sent PE_PRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Source off PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 899  A PR_Swap Message is received. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Send_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is required. 8.3.3.19.4.2 PE_PRS_SNK_SRC_Evaluate_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall ask the Device Policy Manager whether a Power Role Swap can be made. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Accept_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is OK. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Reject_Swap state when:  The Device Policy Manager indicates that a Power Role Swap is not OK. 8.3.3.19.4.3 PE_PRS_SNK_SRC_Accept_Swap State On entry to the PE_PRS_SNK_SRC_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message and Shall disable the Fast Role Swap receiver if this is enabled. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  The Accept Message has been sent. 8.3.3.19.4.4 PE_PRS_SNK_SRC_Transition_to_off State On entry to the PE_PRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Assert_Rp state when:  A PS_RDY Message is received. 8.3.3.19.4.5 PE_PRS_SNK_SRC_Assert_Rp State On entry to the PE_PRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.4.6 PE_PRS_SNK_SRC_Source_on State On entry to the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_PRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The Source Port VBUS is at vSafe5V. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Page 900 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.4.7 PE_PRS_SNK_SRC_Send_Swap State On entry to the PE_PRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send a PR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_SNK_Ready state when:  A Reject Message is received.  Or a Wait Message is received.  Or the SenderResponseTimer times out. The Policy Engine Shall transition to the PE_PRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. 8.3.3.19.4.8 PE_PRS_SNK_SRC_Reject_Swap State On entry to the PE_PRS_SNK_SRC_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a Power Role Swap at this time.  A Wait Message if further evaluation of the Power Role Swap request is required. Note: In this case it is expected that one of the Port Partners will send a PR_Swap Message at a later time (see Section 6.3.12.2, "Wait in response to a PR_Swap Message"). The Policy Engine Shall transition to the PE_SNK_Ready state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 901 8.3.3.19.5 Policy Engine in Source to Sink Fast Role Swap State Diagram Dual-Role Ports that combine Source and Sink functionality Shall comprise Source and Sink Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SRC_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.178, "Dual-Role Port in Source to Sink Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Source to Sink Power Roles and the changes that Shall be followed for error handling. Page 902 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.178 Dual-Role Port in Source to Sink Fast Role Swap State Diagram PE_SRC_Ready PE_FRS_SRC_SNK_ Evaluate_Swap Actions on entry: Ask Device Policy Manager if Fast Role Swap signaled on CC wire Power = Implicit Contract PD = Connected PE_FRS_SRC_SNK_ Transition_to_off Actions on entry: Wait for VBUS to reach vSafe5V Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Wait_Source_on Actions on entry: Send PS_RDY Message Initialize and run PSSourceOnTimer Power = Implicit contract PD = Connected PE_FRS_SRC_SNK_ Accept_Swap Actions on entry: Send Accept Message Power = Implicit Contract PD = Connected Fast Role Swap signaled Accept Message sent PS_RDY Message received PE_SNK_Startup PE_FRS_SRC_SNK_ Assert_Rd Actions on entry: Request DPM to assert Rd Power = Implicit contract PD = Connected VBUS at vSafe5V Rd asserted ErrorRecovery PSSourceOnTimer Timeout | PS_RDY Message not sent after retries (no GoodCRC received) Accept Message not sent after retries (no GoodCRC received) PE_SRC_Hard_Reset FR_Swap Message received Fast Role Swap not signaled Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 903 8.3.3.19.5.1 PE_SRC_Ready State The Fast Role Swap process Shall start only from the PE_SRC_Ready state where power is stable. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Evaluate_Swap state when:  An FR_Swap Message is received. 8.3.3.19.5.2 PE_FRS_SRC_SNK_Evaluate_Swap State On entry to the PE_FRS_SRC_SNK_Evaluate_Swap state the Policy Engine Shall ask the Device Policy Manager whether Fast Role Swap has been signaled on the CC wire. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Accept_Swap state when:  The Device Policy Manager indicates that a Fast Role Swap has been signaled. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Device Policy Manager indicates that a Fast Role Swap is not being signaled. 8.3.3.19.5.3 PE_FRS_SRC_SNK_Accept_Swap State On entry to the PE_FRS_SRC_SNK_Accept_Swap state the Policy Engine Shall request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Transition_to_off state when:  The Accept Message has been sent. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  The Accept Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. 8.3.3.19.5.4 PE_FRS_SRC_SNK_Transition_to_off State On entry to the PE_FRS_SRC_SNK_Transition_to_off state the Policy Engine Shall wait until VBUS has discharged to vSafe5V. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Assert_Rd state when:  The Device Policy Manager indicates that VBUS has discharged to vSafe5V. 8.3.3.19.5.5 PE_FRS_SRC_SNK_Assert_Rd State On entry to the PE_FRS_SRC_SNK_Assert_Rd state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rp to Rd. The Policy Engine Shall transition to the PE_FRS_SRC_SNK_Wait_Source_on state when:  The Device Policy Manager indicates that Rd is asserted. 8.3.3.19.5.6 PE_FRS_SRC_SNK_Wait_Source_on State On entry to the PE_FRS_SRC_SNK_Wait_Source_on state the Policy Engine Shall request the Protocol Layer to send a PS_RDY Message and Shall start the PSSourceOnTimer. On exit from the Source off state the Policy Engine Shall stop the PSSourceOnTimer. The Policy Engine Shall transition to the PE_SNK_Startup when:  A PS_RDY Message is received indicating that the New Source is now applying Rp. The Policy Engine Shall transition to the ErrorRecovery state when: Page 904 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The PSSourceOnTimer times out or  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). Note: A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 905 8.3.3.19.6 Policy Engine in Sink to Source Fast Role Swap State Diagram Dual-Role Ports that combine Sink and Source functionality Shall comprise Sink and Source Policy Engine state machines. In addition, they Should have the capability to do a Fast Role Swap from the PE_SNK_Ready state and Shall return to USB Default Operation on a Hard Reset. Figure 8.179, "Dual-role Port in Sink to Source Fast Role Swap State Diagram" shows the additional state diagram required to perform a Fast Role Swap from Sink to Source Power Roles and the changes that Shall be followed for error handling. Page 906 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 8.179 Dual-role Port in Sink to Source Fast Role Swap State Diagram PE_FRS_SNK_SRC_ Transition_to_off Actions on entry: Initialize and run PSSourceOffTimer Power = Implicit Contract PD = Connected Fast Swap signal detected on CC Wire PE_FRS_SNK_SRC_ Send_Swap Actions on entry: Send FR_Swap Message Initialize and run SenderResponseTimer Power = Implicit Contract PD = Connected Accept Message received PE_FRS_SNK_SRC_ Source_on Actions on entry: Send PS_RDY Message Power = Transition to source on PD = Connected PS_RDY Message sent PE_SRC_Startup PE_FRS_SNK_SRC_ Assert_Rp Actions on entry: Request DPM to assert Rp Power = Implicit Contract PD = Connected PS_RDY Message received Rp asserted ErrorRecovery PS_RDY Message not sent after retries (no GoodCRC received) PSSourceOffTimer timeout SenderResponseTimer timeout | FR_Swap Message not sent after retries (no GoodCRC received) PE_FRS_SNK_SRC_Vbus_Applied Actions on entry: Request Device Policy Manager to notify when vSafe5v is being applied by the local power source. Power = Implicit Contract PD = Connected New Source is applying vSafe5V PE_FRS_SNK_SRC_ Start_AMS Actions on entry: Notify the Protocol Layer that the first Message in the AMS will follow. Power = Implicit Contract PD = Connected Protocol Layer notified Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 907 8.3.3.19.6.1 PE_FRS_SNK_SRC_Start_AMS State The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Start_AMS state from any other state provided there is an Explicit Contract in place when:  The Sink Capabilities received from the Initial Source by the Policy Engine has at least one of the Fast Role Swap bits set.  The system has sufficient reserve power to provide the requested current to the Initial Source, as requested in the Fast Role Swap bits in the Sink Capabilities, and is willing to dedicate it to the Port  The Device Policy Manager indicates that a Fast Role Swap signal has been detected on the CC wire. On entry to the PE_FRS_SNK_SRC_Start_AMS state the Policy Engine Shall notify the Protocol Layer that the first Message in an AMS will follow. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Send_Swap state when:  The Protocol Layer has been notified. 8.3.3.19.6.2 PE_FRS_SNK_SRC_Send_Swap State On entry to the PE_FRS_SNK_SRC_Send_Swap state the Policy Engine Shall request the Protocol Layer to send an FR_Swap Message and Shall initialize and run the SenderResponseTimer. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Transition_to_off state when:  An Accept Message is received. The Policy Engine Shall transition to the ErrorRecovery state when:  The SenderResponseTimer times out or  The FR_Swap Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. 8.3.3.19.6.3 PE_FRS_SNK_SRC_Transition_to_off State On entry to the PE_FRS_SNK_SRC_Transition_to_off state the Policy Engine Shall initialize and run the PSSourceOffTimer and then request the Device Policy Manager to turn off the Sink. The Policy Engine Shall transition to the ErrorRecovery state when:  The PSSourceOffTimer times out. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_VBUS_Applied state when:  A PS_RDY Message is received. 8.3.3.19.6.4 PE_FRS_SNK_SRC_VBUS_Applied State On entry to the PE_FRS_SNK_SRC_VBUS_Applied state the Policy Engine waits for a notification from the Device Policy Manager that the local power source has applied vSafe5V to VBUS (see Section 5.8.6.3, "Fast Role Swap Detection"). Note: This could have already been applied prior to entering this state or could be applied while waiting in this state. The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Assert_Rp state when:  The Device Policy Manager indicates that vSafe5V is being applied. 8.3.3.19.6.5 PE_FRS_SNK_SRC_Assert_Rp State On entry to the PE_FRS_SNK_SRC_Assert_Rp state the Policy Engine Shall request the Device Policy Manager to change the resistor asserted on the CC wire from Rd to Rp. Page 908 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_FRS_SNK_SRC_Source_on state when:  The Device Policy Manager indicates that Rp is asserted. 8.3.3.19.6.6 PE_FRS_SNK_SRC_Source_on State On entry to the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall request the Device Policy Manager to turn on the Source. On exit from the PE_FRS_SNK_SRC_Source_on state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition to the PE_SRC_Startup state when:  The PS_RDY Message has been sent. The Policy Engine Shall transition to the ErrorRecovery state when:  The PS_RDY Message is not sent after retries (a GoodCRC Message has not been received). A Soft Reset Shall Not be initiated in this case. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 909 8.3.3.19.7 Dual-Role (Source Port) Get Source Capabilities State Diagram Figure 8.180, "Dual-Role (Source) Get Source Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.180 Dual-Role (Source) Get Source Capabilities diagram 8.3.3.19.7.1 PE_DR_SRC_Get_Source_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap state, from the PE_SRC_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall request the Protocol Layer to send a get Source Capabilities Message in order to retrieve the Source Capabilities. The Policy Engine Shall send:  A Get_Source_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Source_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready State (see Figure 8.132, "Source Port State Diagram") when:  In SPR Mode and SPR Source Capabilities were requested and a Source_Capabilities Message is received or  In EPR Mode and EPR Source Capabilities were requested and an EPR_Source_Capabilities Message is received or  The SenderResponseTimer times out. get source capabilities request from Device Policy Manager SPR Souce Capabilities requested & Source_Capabilities Message received | EPR Souce Capabilities requested & EPR_Source_Capabilities Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap Actions on entry: If SPR Source Capabilities requested Send Get_Source_Cap Message1 If EPR Source Capabilities requested Send EPR_Get_Source_Cap Message1 Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source capabilities/outcome to Device Policy Manager 1) Either SPR or EPR Source Capabilities May be requested, regardless of whether or not the Source is currently operating in SPR or EPR Mode. Page 910 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.8 Dual-Role (Source Port) Give Sink Capabilities State Diagram Figure 8.181, "Dual-Role (Source) Give Sink Capabilities diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a Get_Sink_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.181 Dual-Role (Source) Give Sink Capabilities diagram 8.3.3.19.8.1 PE_DR_SRC_Give_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap state, from the PE_SRC_Ready state, when a Get_Sink_Cap Message or EPR_Get_Sink_Cap Message is received.  On entry to the PE_DR_SRC_Give_Sink_Cap state the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Sink_Capabilities Message containing these capabilities. The Policy Engine Shall send:  A Sink_Capabilities Message when a Get_Sink_Cap Message is received or  An EPR_Sink_Capabilities Message when a EPR_Get_Sink_Cap Message is received. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  The Sink_Capabilities Message has been successfully sent. Get_Sink_Cap_Extended Message received Sink_Capabilities_Extended Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap_Ext Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 911 8.3.3.19.9 Dual-Role (Sink Port) Get Sink Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's Sink Capabilities. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.182 Dual-Role (Sink) Get Sink Capabilities State Diagram 8.3.3.19.9.1 PE_DR_SNK_Get_Sink_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap state, from the PE_SNK_Ready state, due to a request to get the remote Source Capabilities from the Device Policy Manager.  On entry to the PE_DR_SNK_Get_Sink_Cap state the Policy Engine Shall request the Protocol Layer to send a Get_Sink_Cap Message in order to retrieve the Sink Capabilities. The Policy Engine Shall send:  A Get_Sink_Cap Message when the Device Policy Manager requests SPR capabilities or  An EPR_Get_Sink_Cap Message when the Device Policy Manager requests EPR Capabilities. The Policy Engine Shall then start the SenderResponseTimer. On exit from the PE_SRC_Get_Sink_Cap state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). If Fast Role Swap is supported, request Device Policy Manager prepare or disable 5V source and configure the Fast Role Swap receiver based on the Fast Role Swap required USB Type- C Current bits in the received Sink Capabilities. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  SPR Sink Capabilities were requested and a Sink_Capabilities Message is received or  EPR Sink Capabilities were requested and an EPR_Sink_Capabilities Message is received or  The SenderResponseTimer times out. PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap Actions on entry: If SPR Mode capabilities requested send Get_Sink_Cap Message If EPR Mode capabilities requested send EPR_Get_Sink_Cap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected get sink capabilities request from Device Policy Manager1 (SPR Sink Capabilities requested & Sink_Capabilities Message) | (EPR Sink Capabilities requested & EPR_Sink_Capabilities Message) | SenderResponseTimer timeout Actions on exit: Pass sink capabilities/outcome to Device Policy Manager Request Device Policy Manager to configure Fast Role Swap if supported 1) Either SPR or EPR Sink Capabilities May be requested, regardless of whether or not the Sink is currently operating in SPR or EPR Mode. Page 912 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.10 Dual-Role (Sink Port) Give Source Capabilities State Diagram Figure 8.182, "Dual-Role (Sink) Get Sink Capabilities State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap Message. See also Section , "A Source Port Shall report its Capabilities in a series of 32-bit Power Data Objects (see Table 6.7, "Power Data Object") as part of a Source_Capabilities Message (see Figure 6.13, "Example Capabilities Message with 2 Power Data Objects"). Power Data Objects are used to convey a Source Port's Capabilities to provide power including Dual-Role Power ports presently operating as a Sink.". Figure 8.183 Dual-Role (Sink) Give Source Capabilities State Diagram 8.3.3.19.10.1 PE_DR_SNK_Give_Source_Cap State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap state, from the PE_SNK_Ready state, when a Get_Source_Cap Message is received.  On entry to the PE_DR_SNK_Give_Source_Cap State the Policy Engine Shall request the Device Policy Manager for the current system capabilities. The Policy Engine Shall then request the Protocol Layer to send a Source Capabilities Message containing these capabilities.  The Policy Engine Shall send:  A Source_Capabilities Message when a Get_Source_Cap Message is received or  An EPR_Source_Capabilities Message when a EPR_Get_Source_Cap Message is received. The Policy Engine Shall transition to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source Capabilities Message has been successfully sent. (In EPR Mode & Get_Source_Cap Message) | (In SPR Mode & EPR_Get_Source_Cap Message) Source capabilities Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap Actions on entry: Get present Source capabilities from Device Policy Manager Send Capabilities Message (based on Device Policy Manager response): • If Get_Source_Cap Message received send Source_Capabilities Message. • In EPR_Get_Source_Cap Message received send EPR_Source_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 913 8.3.3.19.11 Dual-Role (Source Port) Get Source Capabilities Extended State Diagram Figure 8.184, "Dual-Role (Source) Get Source Capabilities Extended State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's extended Source Capabilities. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.184 Dual-Role (Source) Get Source Capabilities Extended State Diagram 8.3.3.19.11.1 PE_DR_SRC_Get_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Cap_Ext state, from the PE_SRC_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall send a Get_Source_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Capabilities_Extended Message is received  Or SenderResponseTimer times out. get extended source capabilities request from Device Policy Manager Source_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Cap_Ext Actions on entry: Send Get_Source_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source extended capabilities/outcome to Device Policy Manager Page 914 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.12 Dual-Role (Sink Port) Give Source Capabilities Extended State Diagram Figure 8.185, "Dual-Role (Sink) Give Source Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Cap_Extended Message. See also Section 6.5.1, "Source_Capabilities_Extended Message". Figure 8.185 Dual-Role (Sink) Give Source Capabilities Extended diagram 8.3.3.19.12.1 PE_DR_SNK_Give_Source_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Cap_Ext state, from the PE_SNK_Ready state, when a Get_Source_Cap_Extended Message is received. On entry to the PE_DR_SNK_Give_Source_Cap_Ext state the Policy Engine Shall request the present extended Source Capabilities from the Device Policy Manager and then send a Source_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Capabilities_Extended Message has been successfully sent. Get_Source_Cap_Extended Message received Source_Capabilities_Extended Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Cap_Ext Actions on entry: Get present extended source capabilities from Device Policy Manager Send Source_Capabilities_Extended Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 915 8.3.3.19.13 Dual-Role (Sink Port) Get Sink Capabilities Extended State Dia- gram Figure 8.186, "Dual-Role (Sink) Get Sink Capabilities Extended State Diagram" shows the state diagram for a Dual- Role device, presently operating as a Sink, on receiving a request from the Device Policy Manager to get the Port Partner's extended Sink Capabilities. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.186 Dual-Role (Sink) Get Sink Capabilities Extended State Diagram 8.3.3.19.13.1 PE_DR_SNK_Get_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SNK_Get_Sink_Cap_Ext state, from the PE_SNK_Ready state, due to a request to get the remote extended Source Capabilities from the Device Policy Manager. On entry to the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall send a Get_Sink_Cap_Extended Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SNK_Get_Sink_Cap_Ext state the Policy Engine Shall inform the Device Policy Manager of the outcome (capabilities or response timeout). The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  A Sink_Capabilities_Extended Message is received.  Or SenderResponseTimer times out. get extended Sink capabilities request from Device Policy Manager Sink_Capabilities_Extended Message received | SenderResponseTimer Timeout PE_SNK_Ready PE_DR_SNK_Get_Sink_Cap_Ext Actions on entry: Send Get_Sink_Cap_Extended Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass Sink extended capabilities/outcome to Device Policy Manager Page 916 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.14 Dual-Role (Source Port) Give Sink Capabilities Extended State Diagram Figure 8.187, "Dual-Role (Source) Give Sink Capabilities Extended diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Sink_Cap_Extended Message. See also Section 6.5.13, "Sink_Capabilities_Extended Message". Figure 8.187 Dual-Role (Source) Give Sink Capabilities Extended diagram 8.3.3.19.14.1 PE_DR_SRC_Give_Sink_Cap_Ext State The Policy Engine Shall transition to the PE_DR_SRC_Give_Sink_Cap_Ext state, from the PE_SRC_Ready state, when a Get_Sink_Cap_Extended Message is received. On entry to the PE_DR_SRC_Give_Sink_Cap_Ext state the Policy Engine Shall request the present extended Sink Capabilities from the Device Policy Manager and then send a Sink_Capabilities_Extended Message based on these capabilities. The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram")when:  The Sink_Capabilities_Extended Message has been successfully sent. _Get_Sink_Cap Message | EPR_Get_Sink_Cap Message Sink Capabilities Message sent PE_SRC_Ready PE_DR_SRC_Give_Sink_Cap Actions on entry: Get present extended sink capabilities from Device Policy Manager Send Sink_Capabilities_Extended Message (based on Device Policy Manager response): • If Get_Sink_Cap Message received send Sink_Capabilities Message. • In EPR_Get_Sink Cap Message received send EPR_Sink_Capabilities Message Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 917 8.3.3.19.15 Dual-Role (Source Port) Get Source Information State Diagram Figure 8.188, "Dual-Role (Source) Get Source Information State Diagram" shows the state diagram for a Dual-Role device, presently operating as a Source, on receiving a request from the Device Policy Manager to get the Port Partner's Source information. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.188 Dual-Role (Source) Get Source Information State Diagram 8.3.3.19.15.1 PE_DR_SRC_Get_Source_Info State The Policy Engine Shall transition to the PE_DR_SRC_Get_Source_Info state, from the PE_SRC_Ready state, due to a request to get the remote Source information from the Device Policy Manager. On entry to the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall send a Get_Source_Info Message and initialize and run the SenderResponseTimer. On exit from the PE_DR_SRC_Get_Source_Info state the Policy Engine Shall inform the Device Policy Manager of the outcome (information or response timeout). The Policy Engine Shall transition back to the PE_SRC_Ready state (see Figure 8.132, "Source Port State Diagram") when:  A Source_Info Message is received.  Or SenderResponseTimer times out. get source information request from Device Policy Manager Source_Info Message received | SenderResponseTimer Timeout PE_SRC_Ready PE_DR_SRC_Get_Source_Info Actions on entry: Send Get_Source_Info Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Actions on exit: Pass source information/outcome to Device Policy Manager Page 918 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.19.16 Dual-Role (Sink Port) Give Source Information State Diagram Figure 8.189, "Dual-Role (Source) Give Source Information diagram" shows the state diagram for a Dual-Role device, presently operating as a Sink, on receiving a Get_Source_Info Message. See also Section 6.3.23, "Get_Source_Info Message" and Section 6.4.11, "Source_Info Message". Figure 8.189 Dual-Role (Source) Give Source Information diagram 8.3.3.19.16.1 PE_DR_SNK_Give_Source_Info State The Policy Engine Shall transition to the PE_DR_SNK_Give_Source_Info state, from the PE_SNK_Ready state, when a Get_Source_Info Message is received. On entry to the PE_DR_SNK_Give_Source_Info state the Policy Engine Shall request the present Source information from the Device Policy Manager and then send a Source_Info Message based on this information. The Policy Engine Shall transition back to the PE_SNK_Ready state (see Figure 8.133, "Sink Port State Diagram") when:  The Source_Info Message has been successfully sent. Get_Source_Info Message received Source_Info Message sent PE_SNK_Ready PE_DR_SNK_Give_Source_Info Actions on entry: Get present source information from Device Policy Manager Send Source_Info Message (based on Device Policy Manager response) Power = Explicit Contract PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 919 8.3.3.20 VCONN Swap State Diagram The State Diagram in this section Shall apply to Ports that supply VCONN. Figure 8.190, "VCONN Swap State Diagram" shows the state operation for a Port on sending or receiving a VCONN Swap request. Figure 8.190 VCONN Swap State Diagram 8.3.3.20.1 PE_VCS_Send_Swap State The PE_VCS_Send_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a request from the Device Policy Manager to perform a VCONN Swap. On entry to the PE_VCS_Send_Swap state the Policy Engine Shall send a VCONN_Swap Message and start the SenderResponseTimer. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  An Accept Message is received and  The Port is presently the VCONN Source. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  An Accept Message is received and  The Port is not presently the VCONN Source. PE_VCS_Evaluate_Swap Actions on entry: Get evaluation of VCONN swap request from Device Policy Manager Power = Explicit Contract PD = Connected PE_VCS_Turn_On_VCONN Actions on entry: Tell Device Policy Manager to turn on VCONN PE_VCS_Send_PS_Rdy Actions on entry: Send PS_RDY Message PE_VCS_Accept_Swap Actions on entry: Send Accept Message Power = Explicit Contract PD = Connected PE_VCS_Reject_VCONN_Swap Actions on entry: Send Reject or Wait Message as appropriate Power = Explicit Contract PD = Connected Message sent VCONN_Swap Message received VCONN Swap ok (Not Presently VCONN SOURCE & VCONN Swap not ok) | Further evaluation Required Accept Message sent & Not presently VCONN Source1 VCONN turned on PS_RDY Message sent VCONNOnTimer Timeout Hard Reset: Consumer/Provider -> PE_SNK_Hard_Reset Provider/Consumer -> PE_SRC_Hard_Reset Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected PE_VCS_Wait_for_VCONN Actions on entry: Start VCONNOnTimer Power = Explicit Contract PD = Connected Accept Message sent & Presently VCONN Source1 PE_VCS_Turn_Off_VCONN Actions on entry: Tell Device Policy Manager to turn off VCONN Power = Explicit Contract PD = Connected PS_RDY Message received Device Policy Manager Informed VCONN Swap required (indication from Device Policy Manager) PE_VCS_Send_Swap Actions on entry: Send VCONN_Swap Message Initialize and run SenderResponseTimer Power = Explicit Contract PD = Connected Reject Message received | Wait Message received | SenderResponseTimer timeout Accept Message received & Presently VCONN Source1 Accept Message received & Not presently VCONN Source1 PE_VCS_Force_VCONN2 Actions on entry: Tell Device Policy Manager to turn on VCONN Power = Explicit Contract PD = Connected Not_Supported Message received & Not presently VCONN Source1 VCONN turned on PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Entry_ACK PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_SNK_EPR_Mode_Entry_Wait_For_Response PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable 1) A Port is presently the VCONN Source if it has the responsibility for supplying VCONN even if VCONN has been turned off. 2) The PE_VCS_Force_VCONN state is Optional. Page 920 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  A Reject Message is received or  A Wait Message is received or  The SenderResponseTimer times out. The Policy Engine May transition to the PE_VCS_Force_VCONN state when:  A Not_Supported Message is received and  The Port is not presently the VCONN Source. 8.3.3.20.2 PE_VCS_Evaluate_Swap State The PE_VCS_Evaluate_Swap state is entered from either the PE_SRC_Ready or PE_SNK_Ready state when the Policy Engine receives a VCONN_Swap Message. On entry to the PE_VCS_Evaluate_Swap state the Policy Engine Shall request the Device Policy Manager for an evaluation of the VCONN Swap request. The Policy Engine Shall transition to the PE_VCS_Accept_Swap state when:  The Device Policy Manager indicates that a VCONN Swap is OK. The Policy Engine Shall transition to the PE_VCS_Reject_Swap state when:  The Port is not presently the VCONN Source and the Device Policy Manager indicates that a VCONN Swap is not OK or  The Device Policy Manager indicates that a VCONN Swap cannot be done at this time. 8.3.3.20.3 PE_VCS_Accept_Swap State On entry to the PE_VCS_Accept_Swap state the Policy Engine Shall send an Accept Message. The Policy Engine Shall transition to the PE_VCS_Wait_For_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is on. The Policy Engine Shall transition to the PE_VCS_Turn_On_VCONN state when:  The Accept Message has been sent and  The Port's VCONN is off. 8.3.3.20.4 PE_VCS_Reject_Swap State On entry to the PE_VCS_Reject_Swap state the Policy Engine Shall request the Protocol Layer to send:  A Reject Message if the device is unable to perform a VCONN Swap at this time.  A Wait Message if further evaluation of the VCONN Swap request is required. Note: In this case it is expected that the Port will send a VCONN_Swap Message at a later time. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Reject or Wait Message has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 921 8.3.3.20.5 PE_VCS_Wait_for_VCONN State On entry to the PE_VCS_Wait_For_VCONN state the Policy Engine Shall start the VCONNOnTimer. The Policy Engine Shall transition to the PE_VCS_Turn_Off_VCONN state when:  A PS_RDY Message is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state when:  The VCONNOnTimer times out. 8.3.3.20.6 PE_VCS_Turn_Off_VCONN State On entry to the PE_VCS_Turn_Off_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn off VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Device Policy Manager has been informed. 8.3.3.20.7 PE_VCS_Turn_On_VCONN State On entry to the PE_VCS_Turn_On_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition to the PE_VCS_Send_Ps_Rdy state when:  The Port's VCONN is on. 8.3.3.20.8 PE_VCS_Send_PS_Rdy State On entry to the PE_VCS_Send_Ps_Rdy state the Policy Engine Shall send a PS_RDY Message. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The PS_RDY Message has been sent. 8.3.3.20.9 PE_VCS_Force_VCONN State On entry to the PE_VCS_Force_VCONN state the Policy Engine Shall tell the Device Policy Manager to turn on VCONN. The Policy Engine Shall transition back to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable state when:  The Port's VCONN is on. 8.3.3.21 Initiator Structured VDM State Diagrams The State Diagrams in this section Shall apply to all Initiators. Page 922 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.1 Initiator Structured VDM Discover Identity State Diagram Figure 8.191, "Initiator to Port VDM Discover Identity State Diagram" shows the state diagram for an Initiator when discovering the identity of its Port Partner or Cable Plug. Figure 8.191 Initiator to Port VDM Discover Identity State Diagram 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_Request State The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the identity of the Port Partner or Cable Plug or  The DiscoverIdentityTimer times out. The Policy Engine transitions to the PE_INIT_PORT_VDM_Identity_Request state from the PE_SRC_EPR_Mode_Discover_Cable state when:  The Cable Plug Discovery Process has been initiated. PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Discover_Cable PE_INIT_PORT_VDM_Identity_Request Actions on entry: Send Discover Identity request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests identity discovery1 | DiscoverIdentityTimer timeout Discover Identity ACK received PE_INIT_PORT_VDM_Identity_ACKed Actions on entry: Inform DPM of identity Power = Explicit Contract PD = Connected PE_INIT_PORT_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR 1) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 923 On entry to the PE_INIT_PORT_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out. 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_ACKed State On entry to the PE_INIT_PORT_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. 8.3.3.21.1.3 PE_INIT_PORT_VDM_Identity_NAKed State On entry to the PE_INIT_PORT_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The Device Policy Manager has been informed. Page 924 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.2 Initiator Structured VDM Discover SVIDs State Diagram Figure 8.192, "Initiator VDM Discover SVIDs State Diagram" shows the state diagram for an Initiator when discovering SVIDs of its Port Partner or Cable Plug. Figure 8.192 Initiator VDM Discover SVIDs State Diagram 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_Request State The Policy Engine transitions to the PE_INIT_VDM_SVIDs_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the SVIDs of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_SVIDs_Request state the Policy Engine Shall send a Structured VDM Discover SVIDs Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_ACKed state when:  A Structured VDM Discover SVIDs ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_SVIDs_NAKed state when:  A Structured VDM Discover SVIDs NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_SVIDs_Request Actions on entry: Send Discover SVIDs request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests SVIDs discovery Discover SVIDs ACK received PE_INIT_VDM_SVIDs_ACKed Actions on entry: Inform DPM of SVIDs Power = Explicit Contract PD = Connected PE_INIT_VDM_SVIDs_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover SVIDs NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 925 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_ACKed State On entry to the PE_INIT_VDM_SVIDs_ACKed state the Policy Engine Shall inform the Device Policy Manager of the SVIDs information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. 8.3.3.21.2.3 PE_INIT_VDM_SVIDs_NAKed State On entry to the PE_INIT_VDM_SVIDs_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. Page 926 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.3 Initiator Structured VDM Discover Modes State Diagram Figure 8.193, "Initiator VDM Discover Modes State Diagram" shows the state diagram for an Initiator when discovering Modes of its Port Partner or Cable Plug. Figure 8.193 Initiator VDM Discover Modes State Diagram 8.3.3.21.3.1 PE_INIT_VDM_Modes_Request State The Policy Engine transitions to the PE_INIT_VDM_Modes_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager requests the discovery of the Modes of the Port Partner or a Cable Plug. On entry to the PE_INIT_VDM_Modes_Request state the Policy Engine Shall send a Structured VDM Discover Modes Command request and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_ACKed state when:  A Structured VDM Discover Modes ACK Command response is received. The Policy Engine Shall transition to the PE_INIT_VDM_Modes_NAKed state when:  A Structured VDM Discover Modes NAK or BUSY Command response is received or  The VDMResponseTimer times out. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Modes_Request Actions on entry: Send Discover Modes request Start VDMResponseTimer Power = Explicit Contract PD = Connected DPM requests Modes discovery Discover Modes ACK received PE_INIT_VDM_Modes_ACKed Actions on entry: Inform DPM of Modes Power = Explicit Contract PD = Connected PE_INIT_VDM_Modes_NAKed Actions on entry: Inform DPM of result Power = Explicit Contract PD = Connected Discover Modes NAK/BUSY | VDMResponseTimer Timeout DPM informed DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 927 8.3.3.21.3.2 PE_INIT_VDM_Modes_ACKed State On entry to the PE_INIT_VDM_Modes_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Modes information. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. 8.3.3.21.3.3 PE_INIT_VDM_Modes_NAKed State On entry to the PE_INIT_VDM_Modes_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Page 928 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.21.4 Initiator Structured VDM Attention State Diagram Figure 8.194, "Initiator VDM Attention State Diagram" shows the state diagram for an Initiator when sending an Attention Command request. Figure 8.194 Initiator VDM Attention State Diagram 8.3.3.21.4.1 PE_INIT_VDM_Attention_Request State The Policy Engine transitions to the PE_INIT_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  When the Device Policy Manager requests attention from its Port Partner. On entry to the PE_INIT_VDM_Attention_Request state the Policy Engine Shall send an Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Attention Command request has been sent. PE_SRC_Ready or PE_SNK_Ready PE_INIT_VDM_Attention_Request Actions on entry: Send Attention Command request Power = Explicit Contract PD = Connected Attention request from DPM Attention Command request sent Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 929 8.3.3.22 Responder Structured VDM State Diagrams 8.3.3.22.1 Responder Structured VDM Discover Identity State Diagram Figure 8.195, "Responder Structured VDM Discover Identity State Diagram" shows the state diagram for a Responder receiving a Discover Identity Command request. Figure 8.195 Responder Structured VDM Discover Identity State Diagram 8.3.3.22.1.1 PE_RESP_VDM_Get_Identity State The Policy Engine transitions to the PE_RESP_VDM_Get_Identity state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Identity Command request is received. On entry to the PE_RESP_VDM_Get_Identity state the Responder Shall request identity information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Identity state when:  Identity information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Identity_NAK state when:  The Device Policy Manager indicates that the response to the Discover Identity Command request is NAK or BUSY. 8.3.3.22.1.2 PE_RESP_VDM_Send_Identity State On entry to the PE_RESP_VDM_Send_Identity state the Responder Shall send the Structured VDM Discover Identity ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Discover Identity ACK Command response has been sent. 8.3.3.22.1.3 PE_RESP_VDM_Get_Identity_NAK State On entry to the PE_RESP_VDM_Get_Identity_NAK state the Policy Engine Shall send a Structured VDM Discover Identity NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Identity NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Identity Actions on entry: Send Discover Identity ACK Power = Explicit Contract PD = Connected Discover Identity request Discover Identity ACK sent PE_RESP_VDM_Get_Identity Actions on entry: Request Identity information from DPM Power = Explicit Contract PD = Connected Identity information from DPM PE_RESP_VDM_Get_Identity_NAK Actions on entry: Send Discover Identity NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Identity NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 930 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.2 Responder Structured VDM Discover SVIDs State Diagram Figure 8.196, "Responder Structured VDM Discover SVIDs State Diagram" shows the state diagram for a Responder when receiving a Discover SVIDs Command. Figure 8.196 Responder Structured VDM Discover SVIDs State Diagram 8.3.3.22.2.1 PE_RESP_VDM_Get_SVIDs State The Policy Engine transitions to the PE_RESP_VDM_Get_SVIDs state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover SVIDs Command request is received. On entry to the PE_RESP_VDM_Get_SVIDs state the Responder Shall request SVIDs information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_SVIDs state when:  SVIDs information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_SVIDs_NAK state when:  The Device Policy Manager indicates that the response to the Discover SVIDs Command request is NAK or BUSY. 8.3.3.22.2.2 PE_UFP_VDM_Send_SVIDs State On entry to the PE_RESP_VDM_Send_SVIDs state the Responder Shall send the Structured VDM Discover SVIDs ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs ACK Command response has been sent. 8.3.3.22.2.3 PE_UFP_VDM_Get_SVIDs_NAK State On entry to the PE_RESP_VDM_Get_SVIDs_NAK state the Policy Engine Shall send a Structured VDM Discover SVIDs NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover SVIDs NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_SVIDs Actions on entry: Send Discover SVIDs ACK Power = Explicit Contract PD = Connected Discover SVIDs request Discover SVIDs ACK sent PE_RESP_VDM_Get_SVIDs Actions on entry: Request SVIDs information from DPM Power = Explicit Contract PD = Connected SVIDs information from DPM PE_RESP_VDM_Get_SVIDs_NAK Actions on entry: Send Discover SVIDs NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover SVIDs NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 931 8.3.3.22.3 Responder Structured VDM Discover Modes State Diagram Figure 8.197, "Responder Structured VDM Discover Modes State Diagram" shows the state diagram for a Responder on receiving a Discover Modes Command. Figure 8.197 Responder Structured VDM Discover Modes State Diagram 8.3.3.22.3.1 PE_RESP_VDM_Get_Modes State The Policy Engine transitions to the PE_RESP_VDM_Get_Modes state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A Structured VDM Discover Modes Command request is received. On entry to the PE_RESP_VDM_Get_Modes state the Responder Shall request Modes information from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Send_Modes state when:  Modes information is received from the Device Policy Manager. The Policy Engine Shall transition to the PE_RESP_VDM_Get_Modes_NAK state when:  The Device Policy Manager indicates that the response to the Discover Modes Command request is NAK or BUSY. 8.3.3.22.3.2 PE_RESP_VDM_Send_Modes State On entry to the PE_RESP_VDM_Send_Modes state the Responder Shall send the Structured VDM Discover Modes ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes ACK Command response has been sent. 8.3.3.22.3.3 PE_RESP_VDM_Get_Modes_NAK State On entry to the PE_RESP_VDM_Get_Modes_NAK state the Policy Engine Shall send a Structured VDM Discover Modes NAK or BUSY Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  The Structured VDM Discover Modes NAK or BUSY Command response has been sent. PE_RESP_VDM_Send_Modes Actions on entry: Send Discover Modes ACK Power = Explicit Contract PD = Connected Discover Modes request Discover Modes ACK sent PE_RESP_VDM_Get_Modes Actions on entry: Request Modes information from DPM Power = Explicit Contract PD = Connected Modes information from DPM PE_RESP_VDM_Get_Modes_ NAK Actions on entry: Send Discover Modes NAK/BUSY Command response as requested Power = Explicit Contract PD = Connected DPM says NAK/BUSY Discover Modes NAK/BUSY sent PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready Page 932 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.22.4 Receiving a Structured VDM Attention State Diagram Figure 8.198, "Receiving a Structured VDM Attention State Diagram" shows the state diagram when receiving an Attention Command request. Figure 8.198 Receiving a Structured VDM Attention State Diagram 8.3.3.22.4.1 PE_RCV_VDM_Attention_Request State The Policy Engine transitions to the PE_RCV_VDM_Attention_Request state from either the PE_SRC_Ready or PE_SNK_Ready state when:  An Attention Command request is received. On entry to the PE_RCV_VDM_Attention_Request state the Policy Engine Shall inform the Device Policy Manager of the Attention Command request. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state when:  The Device Policy Manager has been informed. PE_SRC_Ready or PE_SNK_Ready PE_RCV_VDM_Attention_Request Actions on entry: Inform Device Policy Manager of Attention Command request Power = Explicit Contract PD = Connected Attention Command request received DPM informed Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 933 8.3.3.23 DFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all DFPs that support Structured VDMs. 8.3.3.23.1 DFP Structured VDM Mode Entry State Diagram Figure 8.199, "DFP VDM Mode Entry State Diagram" shows the state operation for a DFP when entering a Mode. Figure 8.199 DFP VDM Mode Entry State Diagram 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Entry_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug enter a Mode. On entry to the PE_DFP_VDM_Mode_Entry_Request state the Policy Engine Shall send a Structured VDM Enter Mode Command request and Shall start the VDMModeEntryTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Enter Mode ACK Command response is received. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_NAKed state when:  A Structured VDM Enter Mode NAK or BUSY Command response is received or  The VDMModeEntryTimer times out. PE_SRC_Ready or PE_SNK_Ready (DFP) DPM requests Mode entry1 PE_DFP_VDM_Mode_Entry_ACKed Actions on entry: Request DPM to enter the mode Power = Explicit Contract PD = Connected PE_DFP_VDM_Mode_Entry_Request Actions on entry: Send Mode Entry request Start VDMModeEntryTimer Power = Explicit Contract PD = Connected Mode Entry ACK received Mode entered PE_DFP_VDM_Mode_Entry_NAKed Actions on entry: Inform DPM of reason for failure Power = Explicit Contract PD = Connected Mode Entry NAK/BUSY Received | VDMModeEntryTimer timeout | Protocol Error3 DPM informed2 1) The Device Policy Manager Shall have placed the system into USB Safe State before issuing this request when entering Modal operation. 2) The Device Policy Manager Shall have returned the system to USB operation if not in Modal operation at this point. 3) Protocol Errors are handled by informing the DPM, returning to USB Safe State and then processing the Message once the PE_SRC_Ready or PE_SNK_Ready state has been entered. Page 934 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_ACKed State On entry to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall request the Device Policy Manager to enter the Mode. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Mode has been entered. 8.3.3.23.1.3 PE_DFP_VDM_Mode_Entry_NAKed State On entry to the PE_DFP_VDM_Mode_Entry_NAKed state the Policy Engine Shall inform the Device Policy Manager of the reason for failure (NAK, BUSY, timeout or Protocol Error). The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 935 8.3.3.23.2 DFP Structured VDM Mode Exit State Diagram Figure 8.200, "DFP VDM Mode Exit State Diagram" shows the state diagram for a DFP when exiting a Mode. Figure 8.200 DFP VDM Mode Exit State Diagram 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_Request State The Policy Engine transitions to the PE_DFP_VDM_Mode_Exit_Request state from either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when:  The Device Policy Manager requests that the Port Partner or a Cable Plug exit a Mode. On entry to the PE_DFP_VDM_Mode_Exit_Request state the Policy Engine Shall send a Structured VDM Exit Mode Command request and Shall start the VDMModeExitTimer. The Policy Engine Shall transition to the PE_DFP_VDM_Mode_Entry_ACKed state when:  A Structured VDM Exit Mode ACK or NAK Command response is received. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state depending on the present Power Role when:  A Structured VDM Exit Mode BUSY Command response is received or  The VDMModeExitTimer times out. 8.3.3.23.2.2 PE_DFP_VDM_DFP_Mode_Exit_ACKed State On Exit to the PE_DFP_VDM_Mode_Entry_ACKed state the Policy Engine Shall inform the Device Policy Manager Of the result: ACK or NAK. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a DFP when: PE_SRC_Ready or PE_SNK_Ready (DFP) PE_DFP_VDM_Mode_Exit_Request Actions on entry: Send Exit Mode request Start VDMModeExitTimer Power = Explicit Contract PD = Connected DPM indicates Mode exit PE_DFP_VDM_Exit_Mode_ACKed Actions on entry: Inform DPM of ACK or NAK Power = Explicit Contract PD = Connected Exit Mode ACK/NAK received DPM informed1 PE_SRC_Hard_Reset or PE_SNK_Hard_Reset (DFP) Exit Mode BUSY Received | VDMModeExitTimer Timeout 1) The Device Policy Manager is required to return the system to USB operation at this point when exiting Modal Operation. Page 936 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 937 8.3.3.24 UFP Structured VDM State Diagrams The State Diagrams in this section Shall apply to all UFPs that support Structured VDMs. 8.3.3.24.1 UFP Structured VDM Enter Mode State Diagram Figure 8.201, "UFP Structured VDM Enter Mode State Diagram" shows the state diagram for a UFP in response to an Enter Mode Command. Figure 8.201 UFP Structured VDM Enter Mode State Diagram 8.3.3.24.1.1 PE_UFP_VDM_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_UFP_VDM_Evaluate_Mode_Entry state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_UFP_VDM_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected Enter Modes request1 PE_UFP_VDM_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_UFP_VDM_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_UFP_VDM_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 938 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_ACK State On entry to the PE_UFP_VDM_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.24.1.3 PE_UFP_VDM_Mode_Entry_NAK State On entry to the PE_UFP_VDM_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 939 8.3.3.24.2 UFP Structured VDM Exit Mode State Diagram Figure 8.202, "UFP Structured VDM Exit Mode State Diagram" shows the state diagram for a UFP in response to an Exit Mode Command. Figure 8.202 UFP Structured VDM Exit Mode State Diagram 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit State The Policy Engine transitions to the PE_UFP_VDM_Mode_Exit state from either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_UFP_VDM_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_UFP_VDM_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. PE_UFP_VDM_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Power = Explicit Contract PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_UFP_VDM_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Power = Explicit Contract PD = Connected Mode exited PE_SRC_Ready or PE_SNK_Ready (UFP) Actions on entry: Power = Explicit Contract PD = Connected PE_UFP_VDM_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Power = Explicit Contract PD = Connected DPM says NAK Exit Mode NAK sent 1) The UFP is required to be in USB operation or USB Safe State at this point. Page 940 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_ACK State On entry to the PE_UFP_VDM_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.24.2.3 PE_UFP_VDM_Mode_Exit_NAK State On entry to the PE_UFP_VDM_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to either the either the PE_SRC_Ready or PE_SNK_Ready state for a UFP when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 941 8.3.3.25 Cable Plug Specific State Diagrams The State Diagrams in this section Shall apply to all Cable Plugs that support Structured VDMs. 8.3.3.25.1 Cable Plug Cable Ready State Diagram Figure 8.203, "Cable Ready State Diagram" shows the Cable Ready state diagram for a Cable Plug. Figure 8.203 Cable Ready State Diagram 8.3.3.25.1.1 PE_CBL_Ready State The PE_CBL_Ready state shown in the following sections is the normal operational state for a Cable Plug and where it starts after power up or a Hard/Cable Reset. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Power up | Hard Reset Complete | Cable Reset Complete Page 942 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2 Soft/Hard/Cable Reset 8.3.3.25.2.1 Cable Plug Soft Reset State Diagram Figure 8.204, "Cable Plug Soft Reset State Diagram" shows the Cable Plug state diagram on reception of a Soft_Reset Message. Figure 8.204 Cable Plug Soft Reset State Diagram 8.3.3.25.2.1.1 PE_CBL_Soft_Reset State The PE_CBL_Soft_Reset state Shall be entered from any state when a Soft_Reset Message is received from the Protocol Layer. On entry to the PE_CBL_Soft_Reset state the Policy Engine Shall reset the Protocol Layer in the Cable Plug and Shall then request the Protocol Layer to send an Accept Message. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Accept Message has been sent or  The Protocol Layer indicates that a transmission error has occurred. Accept Message sent | Transmission Error indication from Protocol Layer Soft Reset Message received PE_CBL_Soft_Reset Actions on entry: Reset Protocol Layer Send Accept Message Cable = Awake PD = Connected PE_CBL_Ready Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 943 8.3.3.25.2.2 Cable Plug Hard Reset State Diagram Figure 8.205, "Cable Plug Hard Reset State Diagram" shows the Cable Plug state diagram for a Hard Reset or Cable Reset. Figure 8.205 Cable Plug Hard Reset State Diagram 8.3.3.25.2.2.1 PE_CBL_Hard_Reset State The PE_CBL_Hard_Reset state Shall be entered from any state when either Hard Reset Signaling or Cable Reset Signaling is detected. On entry to the PE_CBL_Hard_Reset state the Policy Engine Shall reset the Cable Plug (equivalent to a power cycle). The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Cable Plug reset is complete. Hard Reset signalling Received | Cable Reset Command PE_CBL_Hard_Reset Actions on entry: Reset Cable Plug Cable = Awake/Asleep PD = Not Connected Cable reset complete PE_CBL_Ready Page 944 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.3 DFP/VCONN Source SOP'/SOP'' Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram Figure 8.206, "DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the Policy Engine in a VCONN Source when performing a Soft Reset or Cable Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.206 DFP/VCONN Source Soft Reset or Cable Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Soft_Reset State The PE_DFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_DFP_VCS_CBL_Send_Soft_Reset state the DFP Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug/VPD, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the DFP VCONN Source's Power Role, when:  There is no Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Send_Capabilities state or PE_SRC_Discovery state, depending on the DFP's VCONN Source's Power Role, when:  There is an Explicit Contract in place and  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to the PE_DFP_VCS_CBL_Send_Cable_Reset state when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_DFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered| Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error In Explicit Contract & Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_DFP_VCS_CBL_Send_Cable_Reset Actions on entry: Send Cable Reset Message Power = DefauIt/Implicit or Explicit Contract PD = Connected; Cable Discovered Cable Reset Request from Device Policy Manager Cable Reset sent PE_SRC_Send_Capabilities or PE_SRC_Discovery2 (VCONN Source) Not in Explicit Contract & Accept Message Received on SOP’/SOP’’ 1) Excludes the Soft_Reset Message itself. 2) Sink only communicates with the Cable Plug when in an Explicit Contract. If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 945 8.3.3.25.2.3.2 PE_DFP_VCS_CBL_Send_Cable_Reset State The PE_DFP_VCS_CBL_Send_Cable_Reset state Shall be entered from any state when the Device Policy Manager requests a Cable Reset. On entry to the PE_DFP_VCS_CBL_Send_Cable_Reset state the DFP Policy Engine Shall request the Protocol Layer to send Cable Reset Signaling. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the VCONN Source's Power Role, when:  Cable Reset Signaling has been sent. Page 946 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.25.2.4 UFP/VCONN Source SOP'/SOP'' Soft Reset of a Cable Plug or VPD State Diagram Figure 8.207, "UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram" below shows the state diagram for the UFP Policy Engine in a VCONN Source when performing a Soft Reset of a Cable Plug or VPD on SOP’/SOP’’. The following sections describe operation in each of the states. Figure 8.207 UFP/VCONN Source Soft Reset of a Cable Plug or VPD State Diagram 8.3.3.25.2.4.1 PE_UFP_VCS_CBL_Send_Soft_Reset State The PE_UFP_VCS_CBL_Send_Soft_Reset state Shall be entered from any state when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer (see Section 6.8.1, "Soft Reset and Protocol Error") or when a Message has not been sent after retries on SOP’/SOP’’ while communicating with a Cable Plug/VPD and when there was previous communication with the Cable Plug that did not result in a Transmission Error or whenever the Device Policy Manager directs a Soft Reset on SOP’/SOP’’. On entry to the PE_UFP_VCS_CBL_Send_Soft_Reset state the Policy Engine Shall request the SOP’/SOP’’ Protocol Layer to perform a Soft Reset, then Shall send a Soft_Reset Message on SOP’/SOP’’ to the Cable Plug, and initialize and run the SenderResponseTimer. The Policy Engine Shall transition to either the PE_SRC_Ready or PE_SNK_Ready state, depending on the UFP VCONN Source's Power Role, when:  An Accept Message has been received on SOP’/SOP’’. The Policy Engine Shall transition to either the PE_SRC_Hard_Reset or PE_SNK_Hard_Reset state, depending on the UFP VCONN Source's Power Role, when:  A SenderResponseTimer timeout occurs  Or the Protocol Layer indicates that a transmission error has occurred  Or when a Protocol Error is detected on SOP’/SOP’’ by the Protocol Layer. PE_UFP_VCS_CBL_Send_Soft_Reset Actions on entry: Reset Protocol Layer Send Soft Reset Message on SOP’/SOP’’ Initialize and run SenderResponseTimer Power = DefauIt/Implicit or Explicit Contract PD = Connected Message not sent after retries on SOP’/SOP’’ (no GoodCRC received)1 & Previously Cable Discovered | Protocol error detected on SOP’/SOP’’ SenderResponseTimer Timeout | Transmission Error indication from Protocol Layer | Protocol Error Accept Message Received on SOP’/SOP’’ PE_SRC_Ready or PE_SNK_Ready (VCONN Source) PE_SRC_Hard_Reset or PE_SNK_Hard_Reset 1) Excludes the Soft_Reset Message itself. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 947 8.3.3.25.3 Source Startup Structured VDM Discover Identity of a Cable Plug State Diagram Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" shows the state diagram for Source discovery of identity information from a Cable Plug during the startup sequence. Figure 8.208 Source Startup Structured VDM Discover Identity State Diagram 8.3.3.25.3.1 PE_SRC_VDM_Identity_Request State The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Startup state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_Request state from the PE_SRC_Discovery state when:  The Device Policy Manager requests the discovery of the identity of the Cable Plug and  The DiscoverIdentityCounter < nDiscoverIdentityCount. Even though there has been a transition out of the PE_SRC_Discovery state the SourceCapabilityTimer Shall continue to run during the states shown in Figure 8.208, "Source Startup Structured VDM Discover Identity State Diagram" and Shall Not be initialized on re-entry to PE_SRC_Discovery. PE_SRC_Send_Capabilities or PE_SRC_Discovery1 PE_SRC_VDM_Identity_Request Actions on entry: Send Discover Identity request Increment the DiscoverIdentityCounter Start VDMResponseTimer Power = No or Implicit Contract Cable Plug = Not PD Connected DPM requests identity discovery3 & Protocol Layer Reset Complete Discover Identity ACK received PE_SRC_VDM_Identity_ACKed Actions on entry: Inform DPM of identity PE_SRC_VDM_Identity_NAKed Actions on entry: Inform DPM of result Power =No or Implicit Contract Cable Plug = PD Connected Discover Identity NAK/BUSY | VDMResponseTimer Timeout | Discover Identity request sending failure (without GoodCRC) DPM informed DPM informed PE_SRC_Startup DPM requests identity discovery & DiscoverIdentityCounter < nDiscoverIdentityCount2 PE_SRC_Discovery Power = No or Implicit Contract Cable Plug = PD Connected 1) If the Discover Identity Command is being sent at startup, then the Policy Engine will subsequently transition to the PE_SRC_Send_Capabilities state as normal. Otherwise, the Policy Engine will transition to the PE_SRC_Discovery state. 2) The SourceCapabilityTimer continues to run during the states defined in this diagram even though there has been an exit from the PE_SRC_Discovery state. This ensures that Source_Capabilities Messages are sent out at a regular rate. 3) The DPM in an EPR Source Shall request the discovery of the identity of the Cable Plug at startup. Page 948 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: An EPR Source is required to discover the identity of the Cable Plug prior to entering the First Explicit Contract (see Section 6.4.10.1, "Process to enter EPR Mode") On entry to the PE_SRC_VDM_Identity_Request state the Policy Engine Shall send a Structured VDM Discover Identity Command request, Shall increment the DiscoverIdentityCounter and Shall start the VDMResponseTimer. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_ACKed state when:  A Structured VDM Discover Identity ACK Command response is received. The Policy Engine Shall transition to the PE_SRC_VDM_Identity_NAKed state when:  A Structured VDM Discover Identity NAK or BUSY Command response is received or  The VDMResponseTimer times out or  The Structured VDM Discover Identity Command request Message sending fails (no GoodCRC Message received after retries). 8.3.3.25.3.2 PE_SRC_VDM_Identity_ACKed State On entry to the PE_SRC_VDM_Identity_ACKed state the Policy Engine Shall inform the Device Policy Manager of the Identity information. The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. 8.3.3.25.3.3 PE_SRC_VDM_Identity_NAKed State On entry to the PE_SRC_VDM_Identity_NAKed state the Policy Engine Shall inform the Device Policy Manager of the result (NAK, BUSY or timeout). The Policy Engine Shall transition back to either the PE_SRC_Send_Capabilities or PE_SRC_Discovery state when:  The Device Policy Manager has been informed. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 949 8.3.3.25.4 Cable Plug Mode Entry/Exit 8.3.3.25.4.1 Cable Plug Structured VDM Enter Mode State Diagram Figure 8.209, "Cable Plug Structured VDM Enter Mode State Diagram" shows the state diagram for a Cable Plug in response to an Enter Mode Command. Figure 8.209 Cable Plug Structured VDM Enter Mode State Diagram 8.3.3.25.4.1.1 PE_CBL_Evaluate_Mode_Entry State The Policy Engine transitions to the PE_CBL_Evaluate_Mode_Entry state from the PE_CBL_Ready state when:  A Structured VDM Enter Mode Command request is received from the DFP. On Entry to the PE_CBL_Evaluate_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the Enter Mode Command request and enter the Mode indicated in the Command request if the request is acceptable. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_ACK state when:  The Device Policy Manager indicates that the Mode has been entered. The Policy Engine Shall transition to the PE_CBL_Mode_Entry_NAK state when:  The Device Policy Manager indicates that the response to the Mode request is NAK. 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_ACK State On entry to the PE_CBL_Mode_Entry_ACK state the Policy Engine Shall send a Structured VDM Enter Mode ACK Command response. PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected Enter Modes request1 PE_CBL_Mode_Entry_ACK Actions on entry: Send Enter Mode ACK Command Cable = Awake PD = Connected Enter Mode ACK sent PE_CBL_Evaluate_Mode_Entry Actions on entry: Request DPM to evaluate request to enter a Mode Cable = Awake PD = Connected PE_CBL_Mode_Entry_NAK Actions on entry: Send Enter Mode NAK Command response as requested Cable = Awake PD = Connected DPM says NAK DPM says Mode entered Enter Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 950 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode ACK Command response has been sent. 8.3.3.25.4.1.3 PE_CBL_Mode_Entry_NAK State On entry to the PE_CBL_Mode_Entry_NAK state the Policy Engine Shall send a Structured VDM Enter Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Enter Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 951 8.3.3.25.4.2 Cable Plug Structured VDM Exit Mode State Diagram Figure 8.210, "Cable Plug Structured VDM Exit Mode State Diagram" shows the state diagram for a Cable Plug in response to an Exit Mode Command. Figure 8.210 Cable Plug Structured VDM Exit Mode State Diagram 8.3.3.25.4.2.1 PE_CBL_Mode_Exit State The Policy Engine transitions to the PE_CBL_Mode_Exit state from the PE_CBL_Ready state when:  A Structured VDM Exit Mode Command request is received from the DFP. On entry to the PE_CBL_Mode_Exit state the Policy Engine Shall request the Device Policy Manager to exit the Mode indicated in the Command. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_ACK state when:  The Device Policy Manager indicates that the Mode has been exited. The Policy Engine Shall transition to the PE_CBL_Mode_Exit_NAK state when:  The Device Policy Manager indicates that the Command response to the Exit Mode Command request is NAK. 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_ACK State On entry to the PE_CBL_Mode_Exit_ACK state the Policy Engine Shall send a Structured VDM Exit Mode ACK Command response. PE_CBL_Mode_Exit Actions on entry: Request DPM to evaluate request to exit the requested Mode Cable = Awake PD = Connected Exit Mode request received Exit Mode ACK sent1 PE_CBL_Mode_Exit_ACK Actions on entry: Send Exit Mode ACK Command Cable = Awake PD = Connected Mode exited PE_CBL_Ready Actions on entry: Cable = Awake/Asleep PD = Not Connected/Connected PE_CBL_Mode_Exit_NAK Actions on entry: Send Exit Mode NAK Command Cable = Awake PD = Connected DPM says NAK Exit Mode NAK sent 1) The Cable is required to be in USB operation or USB Safe State at this point. Page 952 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode ACK Command response has been sent. 8.3.3.25.4.2.3 PE_CBL_Mode_Exit_NAK State On entry to the PE_CBL_Mode_Exit_NAK state the Policy Engine Shall send a Structured VDM Exit Mode NAK Command response as indicated by the Device Policy Manager. The Policy Engine Shall transition to the PE_CBL_Ready state when:  The Structured VDM Exit Mode NAK Command response has been sent. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 953 8.3.3.26 EPR Mode State Diagrams 8.3.3.26.1 Source EPR Mode Entry State Diagram Figure 8.211, "Source EPR Mode Entry State Diagram" shows the state diagram for an EPR Source in response to an EPR_Mode Message. Figure 8.211 Source EPR Mode Entry State Diagram 8.3.3.26.1.1 PE_SRC_Evaluate_EPR_Mode_Entry State The Policy Engine transitions to the PE_SRC_Evaluate_EPR_Mode_Entry state from the PE_SRC_Ready state when:  An EPR_Mode (Enter) Message is received from the Sink. On Entry to the PE_SRC_Evaluate_EPR_Mode_Entry state the Policy Engine Shall request the Device Policy Manager to evaluate the EPR_Mode (Enter) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Ack state when:  The Device Policy Manager indicates that EPR Mode can be entered. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Device Policy Manager indicates that the EPR Mode is not to be entered. EPR_Mode (Enter) received PE_SRC_EPR_Mode_Entry_ACK Actions on entry: Send EPR Enter Mode Acknowledge If Source is not the VCONN Source initiate VCONN Swap process PE_SRC_Evaluate_EPR Mode_Entry Actions on entry: Request DPM to evaluate request to enter EPR Mode Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Failed Actions on entry: Send Enter Mode (Enter Failed) with appropriate failure code. DPM says enter EPR Mode EPR Enter Mode (Enter Failed) sent PE_SRC_Ready PE_VCS_Send_Swap PE_VCS_Force_VCONN or PE_VCS_Send_PS_RDY VCONN Swap Process DPM says don’t enter EPR Mode PE_SRC_EPR_Mode_Discover_Cable Actions on entry: Check Vconn Swap Result if Vconn Swap Process carried out. Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected Power = Explicit Contract PD = Connected EPR Enter Mode (Enter Acknowledged) Sent & Source is VCONN Source & Unknown Cable PE_INIT_PORT_VDM_Identity_Request PE_INIT_PORT_VDM_Identity_ACKed or PE_INIT_PORT_VDM_Identity_NAKed Source is the VCONN Source Cable Discovery Process PE_SRC_EPR_Mode_Evaluate_Cable_EPR Actions on entry: Ask DPM to evaluate Cable Discovery results Power = Explicit Contract PD = Connected PE_SRC_EPR_Mode_Entry_Succeeded Actions on entry: Send EPR Mode (Enter Succeeded) Enter EPR Mode. Power = Explicit Contract PD = Connected VCONN Swap Process Complete Cable Discovery Process Complete Cable Plug is EPR capable PE_SRC_Send_Capabilities EPR Mode Entered Cable Plug is not EPR capable EPR Enter Mode (Enter Acknowledged) Sent & (captive cable | known EPR Capable Cable) EPR Enter Mode (Enter Acknowledged) Sent & Source is not VCONN Source & Unknown Cable Page 954 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.1.2 PE_SRC_EPR_Mode_Entry_Ack State On entry to the PE_SRC_EPR_Mode_Entry_Ack state the Policy Engine Shall send a EPR_Mode (Enter Acknowledged) Message. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is a captive cable or a known EPR Cable. The Policy Engine Shall transition to the PE_VCS_Send_Swap state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is not the VCONN Source and  The cable is unknown. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Discover_Cable state when:  The EPR_Mode (Enter Acknowledged) Message has been sent and  The Source is the VCONN Source and  The cable is unknown. 8.3.3.26.1.3 PE_SRC_EPR_Mode_Discover_Cable State The Policy Engine transitions to the PE_SRC_EPR_Mode_Discover_Cable state from the PE_VCS_Force_VCONN state or PE_VCS_Send_Ps_Rdy state when:  A Source initiated VCONN Swap process has completed. The Policy Engine Shall transition to the PE_INIT_PORT_VDM_Identity_Request state in order to perform Cable Plug discovery when:  The Source is the VCONN Source. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The VCONN Swap process failed (the Source is not the VCONN Source). 8.3.3.26.1.4 PE_SRC_EPR_Mode_Evaluate_Cable_EPR State In the PE_SRC_EPR_Mode_Evaluate_Cable_EPR state the Policy Engine requests the DPM to evaluate the Cable Discovery results. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Succeeded state when:  The Cable Plug is capable of EPR Mode. The Policy Engine Shall transition to the PE_SRC_EPR_Mode_Entry_Failed state when:  The Cable Plug is not capable of EPR Mode. 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Succeeded State On entry to the PE_SRC_EPR_Mode_Entry_Succeeded state the Policy Engine Shall send a EPR_Mode (Enter Succeeded) Message and enter EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  EPR Mode has been entered. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 955 8.3.3.26.1.6 PE_SRC_EPR_Mode_Entry_Failed State On entry to the PE_SRC_EPR_Mode_Entry_Failed state the Policy Engine Shall send a EPR_Mode (Enter Failed) Message. The Policy Engine Shall transition to the PE_SRC_Ready state when:  The EPR_Mode (Enter Failed) Message has been sent. Page 956 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.2 Sink EPR Mode Entry State Diagram Figure 8.212, "Sink EPR Mode Entry State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode Entry process. Figure 8.212 Sink EPR Mode Entry State Diagram 8.3.3.26.2.1 PE_SNK_Send_EPR_Mode_Entry State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Entry state from the PE_SNK_Ready state when:  The DPM requests entry into EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Entry state the Policy Engine Shall send an EPR_Mode (Enter) Message and starts the SenderResponseTimer and the SinkEPREnterTimer. Note: The SinkEPREnterTimer Shall continue to run in every state until it is stopped or times out. The Policy Engine Shall transition to the PE_SNK_EPR_Mode_Wait_For_Response state when:  An EPR_Mode (Enter Acknowledge) Message is received. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or DPM Request EPR Mode Entry PE_SNK_EPR_Mode_Entry_Wait_For_Response Actions on entry: Wait for EPR Enter Mode response PE_SNK_Send_EPR Mode_Entry Actions on entry: Send EPR Mode Entry Message Start SenderResponse Timer Start SinkEPREnterTimer Power = Explicit Contract PD = Connected EPR Enter Mode Acknowledge received PE_SNK_Ready EPR Enter Mode Succeeded received Power = Explicit Contract PD = Connected PE_SNK_Send_Soft_Reset EPR Enter Mode received (!Succceded) | SenderResponseTimer timeout | SinkEPREnterTimer timeout EPR Enter Mode received (!Succceded) | SinkEPREnterTimer timeout Actions on exit: Stop the SinkEPRTimer Enter EPR Mode PE_SNK_Wait_For_Capabilities PE_VCS_Evaluate_Swap VCONN Swap Process VCONN_Swap Message Received VCONN Swap Process completed PE_VCS_Turn_Off_VCONN Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 957  The SenderResponseTimer times out or  The SinkEPREnterTimer times out. 8.3.3.26.2.2 PE_SNK_EPR_Mode_Wait_For_Response State In the State the Policy Engine waits for a confirmation that the EPR Mode entry request has succeeded. On exit from the PE_SNK_EPR_Mode_Wait_For_Response state the Policy Engine Shall stop the SinkEPREnterTimer and enter EPR Mode. The Policy Engine Shall transition to the PE_SNK_Send_Soft_Reset state when:  An EPR_Mode Message is received which is not Enter Succeeded or  The SinkEPREnterTimer times out. The Policy Engine Shall transition to the PE_VCS_Evaluate_Swap State when:  A VCONN_Swap Message is received. The Policy Engine Shall transition back from the PE_VCS_Turn_Off_VCONN State to the PE_SNK_EPR_Mode_Wait_For_Response State when:  The VCONN Swap process has completed. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  An EPR_Mode (Enter Succeeded) Message has been received. Page 958 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.26.3 Source EPR Mode Exit State Diagram Figure 8.213, "Source EPR Mode Exit State Diagram" shows the state diagram for an EPR Source initiating the EPR Mode exit process. Figure 8.213 Source EPR Mode Exit State Diagram 8.3.3.26.3.1 PE_SRC_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SRC_Send_EPR_Mode_Exit state from the PE_SRC_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SRC_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.3.2 PE_SRC_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SRC_EPR_Mode_Exit_Received state from the PE_SRC_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SRC_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SRC_Send_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SRC_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SRC_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SRC_Ready Actions on exit: Exit EPR Mode PE_SRC_Send_Capabilities PE_SRC_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explict Contract with SPR PDO & EPR Mode Exited PE_SRC_Hard_Reset Not in an Explicit Contract with an SPR PDO Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 959 8.3.3.26.4 Sink EPR Mode Exit State Diagram Figure 8.214, "Sink EPR Mode Exit State Diagram" shows the state diagram for an EPR Sink initiating the EPR Mode exit process. Figure 8.214 Sink EPR Mode Exit State Diagram 8.3.3.26.4.1 PE_SNK_Send_EPR_Mode_Exit State The Policy Engine transitions to the PE_SNK_Send_EPR_Mode_Exit state from the PE_SNK_Ready state when:  The DPM requests exit from EPR Mode. On Entry to the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall send an EPR_Mode (Exit) Message. On Exit from the PE_SNK_Send_EPR_Mode_Exit state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  The EPR_Mode (Exit) Message has been sent. 8.3.3.26.4.2 PE_SNK_EPR_Mode_Exit_Received State The Policy Engine transitions to the PE_SNK_EPR_Mode_Exit_Received state from the PE_SNK_Ready state when:  An EPR_Mode (Exit) Message is received. On Entry to the PE_SNK_EPR_Mode_Exit_Received state the Policy Engine Shall exit EPR Mode. The Policy Engine Shall transition to the PE_SNK_Wait_for_Capabilities state when:  In an Explicit Contract with an SPR (A)PDO and  EPR Mode has been exited. The Policy Engine Shall transition to the PE_SNK_Hard_Reset state when:  Not in an Explicit Contract with an SPR (A)PDO. DPM Requests EPR Mode Exit PE_SNK_Send_EPR Mode_Exit Actions on entry: Send EPR Mode Exit Message Power = Explicit Contract PD = Connected EPR Mode Exit Message sent PE_SNK_Ready Actions on exit: Exit EPR Mode PE_SNK_Wait_for_Capabilities PE_SNK_EPR Mode_Exit_Received Actions on entry: Exit EPR Mode Power = Explicit Contract PD = Connected EPR Mode Exit Message Received In Explicit Contract with SPR PDO & EPR Mode Exited PE_SNK_Hard_Reset Not in an Explicit Contract with an SPR PDO Page 960 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27 BIST State diagrams 8.3.3.27.1 BIST Carrier Mode State Diagram Figure 8.215, "BIST Carrier Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Carrier Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.215 BIST Carrier Mode State Diagram 8.3.3.27.1.1 PE_BIST_Carrier_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Carrier_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Carrier Mode BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Carrier_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Carrier Mode (see Section 6.4.3.1, "BIST Carrier Mode") and Shall initialize and run the BISTContModeTimer. BIST message received with Data Object BIST Carrier Mode & VBUS = vSafe5V BISTContModeTimer timeout PE_BIST_Carrier_Mode Actions on entry: Tell Protocol Layer to go to BIST Carrier Mode Initialize and run BISTContModeTimer PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 961 The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  The BISTContModeTimer times out. Page 962 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.2 BIST Test Data Mode State Diagram Figure 8.216, "BIST Test Data Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Test Data Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.216 BIST Test Data Mode State Diagram 8.3.3.27.2.1 PE_BIST_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Test Data BIST Data Object and  VBUS is at vSafe5V. BIST message received with Data Object BIST Test Mode & VBUS = vSafe5V Hard Reset PE_BIST_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Test Mode PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 963 On entry to the PE_BIST_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go into BIST Test Data Mode where it sends no further Messages except for GoodCRC Messages in response to received Messages (see Section 6.4.3.2, "BIST Test Data Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A Hard Reset occurs. Page 964 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.27.3 BIST Shared Capacity Test Mode State Diagram Figure 8.217, "BIST Shared Capacity Test Mode State Diagram" shows the state diagram required by a UUT, which can be either a Source, Sink or Cable Plug, when operating in BIST Shared Capacity Test Mode. Transitions Shall be from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready states. Figure 8.217 BIST Shared Capacity Test Mode State Diagram 8.3.3.27.3.1 PE_BIST_Shared_Capacity_Test_Mode State The Source, Sink or Cable Plug Shall enter the PE_BIST_Shared_Capacity_Test_Mode state from either the PE_SRC_Ready, PE_SNK_Ready or PE_CBL_Ready state when:  A BIST Message is received with a BIST Shared Test Mode Entry BIST Data Object and  VBUS is at vSafe5V. On entry to the PE_BIST_Shared_Capacity_Test_Mode state the Policy Engine Shall tell the Protocol Layer to go to BIST Shared Capacity Test Mode (see Section 6.4.3.3, "BIST Shared Capacity Test Mode"). The Policy Engine Shall transition to either the PE_SRC_Transition_to_default state, PE_SNK_Transition_to_default state or PE_CBL_Ready state (as appropriate) when:  A BIST Message is received with a BIST Shared Test Mode Exit BIST Data Object. BIST message received with Data Object BIST Shared Test Mode Entry BIST message received with Data Object BIST Shared Test Mode Exit PE_BIST_Shared Capacity_Test_Mode Actions on entry: Tell Protocol Layer to go to BIST Shared Capacity Test Mode1. PE_SRC_Transition_to_default or PE_SNK_Transition_to_default or PE_CBL_Ready PE_SRC_Ready or PE_SNK_Ready or PE_CBL_Ready VBUS = vSafe5V PD = Connected 1) The UUT Shall exit BIST Shared Capacity Test Mode when It is powered off. The UUT Shall remain in BIST Shared Capacity Test Mode for any PD event (except when a BIST Shared Test Mode Exit BIST Data Object, is received); specifically the UUT Shall remain in BIST Shared Capacity Test Mode when any of the following PD events occurs: Hard Reset, Cable Reset, Soft Reset, Data Role Swap, Power Role Swap, Fast Role Swap, VCONN Swap. The UUT May leave test mode if the tester makes a request that exceeds the capabilities of the UUT. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 965 8.3.3.28 USB Type-C Referenced States This section contains states cross-referenced from the [USB Type-C 2.4] specification. 8.3.3.28.1 ErrorRecovery state The ErrorRecovery state is used to electronically disconnect Port Partners using the USB Type-C connector. The ErrorRecovery state Shall be entered when there are errors on USB Type-C Ports which cannot be recovered by Hard Reset. The ErrorRecovery state Shall map to USB Type-C ErrorRecovery state operation as defined in the [USB Type-C 2.4] specification. Bus powered Sinks Shall Not be required to meet this requirement as removal of their power will serve the same purpose. On entry to the ErrorRecovery state the Explicit Contract and PD Connection Shall be ended. On exit from the ErrorRecovery state a new Explicit Contract Should be established once the Port Partners have re-connected over the CC wire. Page 966 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 8.3.3.29 Policy Engine States Table 8.154, "Policy Engine States" lists the states used by the various state machines. Table 8.154 Policy Engine States State name Reference SenderResponseTimer SRT_Stopped Section 8.3.3.1.1.1 SRT_Running Section 8.3.3.1.1.2 SRT_Expired Section 8.3.3.1.1.3 Source Port PE_SRC_Startup Section 8.3.3.2.1 PE_SRC_Discovery Section 8.3.3.2.2 PE_SRC_Send_Capabilities Section 8.3.3.2.3 PE_SRC_Negotiate_Capability Section 8.3.3.2.4 PE_SRC_Transition_Supply Section 8.3.3.2.5 PE_SRC_Ready Section 8.3.3.2.6 PE_SRC_Disabled Section 8.3.3.2.7 PE_SRC_Capability_Response Section 8.3.3.2.8 PE_SRC_Hard_Reset Section 8.3.3.2.9 PE_SRC_Hard_Reset_Received Section 8.3.3.2.10 PE_SRC_Transition_to_default Section 8.3.3.2.11 PE_SRC_Give_Source_Cap Section 8.3.3.2.15 PE_SRC_Get_Sink_Cap Section 8.3.3.2.12 PE_SRC_Wait_New_Capabilities Section 8.3.3.2.13 PE_SRC_EPR_Keep_Alive Section 8.3.3.2.14 Sink Port PE_SNK_Startup Section 8.3.3.3.1 PE_SNK_Discovery Section 8.3.3.3.2 PE_SNK_Wait_for_Capabilities Section 8.3.3.3.3 PE_SNK_Evaluate_Capability Section 8.3.3.3.4 PE_SNK_Select_Capability Section 8.3.3.3.5 PE_SNK_Transition_Sink Section 8.3.3.3.6 PE_SNK_Ready Section 8.3.3.3.7 PE_SNK_Hard_Reset Section 8.3.3.3.8 PE_SNK_Transition_to_default Section 8.3.3.3.9 PE_SNK_Give_Sink_Cap Section 8.3.3.3.10 PE_SNK_Get_Source_Cap Section 8.3.3.3.12 PE_SNK_EPR_Keep_Alive Section 8.3.3.3.11 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 967 Soft Reset and Protocol Error Source Port Soft Reset PE_SRC_Send_Soft_Reset Section 8.3.3.4.1.1 PE_SRC_Soft_Reset Section 8.3.3.4.1.2 Sink Port Soft Reset PE_SNK_Send_Soft_Reset Section 8.3.3.4.2.1 PE_SNK_Soft_Reset Section 8.3.3.4.2.2 Data Reset DFP Data Reset PE_DDR_Send_Data_Reset Section 8.3.3.5.1.1 PE_DDR_Data_Reset_Received Section 8.3.3.5.1.2 PE_DDR_Wait_For_VCONN_Off Section 8.3.3.5.1.3 PE_DDR_Perform_Data_Reset Section 8.3.3.5.1.4 UFP Data Reset PE_UDR_Send_Data_Reset Section 8.3.3.5.2.1 PE_UDR_Data_Reset_Received Section 8.3.3.5.2.2 PE_UDR_Turn_Off_VCONN Section 8.3.3.5.2.3 PE_UDR_Send_Ps_Rdy Section 8.3.3.5.2.4 PE_UDR_Wait_For_Data_Reset_Complete Section 8.3.3.5.2.5 Not Supported Message Source Port Not Supported PE_SRC_Send_Not_Supported Section 8.3.3.6.1.1 PE_SRC_Not_Supported_Received Section 8.3.3.6.1.2 PE_SRC_Chunk_Received Section 8.3.3.6.1.3 Sink Port Not Supported PE_SNK_Send_Not_Supported Section 8.3.3.6.2.1 PE_SNK_Not_Supported_Received Section 8.3.3.6.2.2 PE_SNK_Chunk_Received Section 8.3.3.6.2.3 Source Alert Source Port Source Alert PE_SRC_Send_Source_Alert Section 8.3.3.7.1.1 PE_SRC_Wait_for_Get_Status Section 8.3.3.7.1.2 Sink Port Source Alert PE_SNK_Source_Alert_Received Section 8.3.3.7.2.1 Sink Port Sink Alert PE_SNK_Send_Sink_Alert Section 8.3.3.7.3.1 PE_SNK_Wait_for_Get_Status Section 8.3.3.7.3.2 Source Port Sink Alert PE_SRC_Sink_Alert_Received Section 8.3.3.7.4.1 Table 8.154 Policy Engine States State name Reference Page 968 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Source/Sink Extended Capabilities Sink Port Get Source Capabilities Extended PE_SNK_Get_Source_Cap_Ext Section 8.3.3.8.1.1 Source Port Give Source Capabilities Extended PE_SRC_Give_Source_Cap_Ext Section 8.3.3.8.2.1 Source Port Get Sink Capabilities Extended PE_SRC_Get_Sink_Cap_Ext Section 8.3.3.8.3.1 Source Port Give Source Capabilities Extended PE_SNK_Give_Sink_Cap_Ext Section 8.3.3.8.4.1 Source Information Sink Port Get Source Information PE_SNK_Get_Source_Info Section 8.3.3.9.1.1 Source Port Give Source Information PE_SRC_Give_Source_Info Section 8.3.3.9.2.1 Status Get Status PE_Get_Status Section 8.3.3.10.1.1 Give Status PE_Give_Status Section 8.3.3.10.1.1 Sink Port Get PPS Status PE_SNK_Get_PPS_Status Section 8.3.3.10.3.1 Source Port Give PPS Status PE_SRC_Give_PPS_Status Section 8.3.3.10.4.1 Battery Capabilities Get Battery Capabilities PE_Get_Battery_Cap Section 8.3.3.11.1.1 Give Battery Capabilities PE_Give_Battery_Cap Section 8.3.3.11.2.1 Battery Status Get Battery Status PE_Get_Battery_Status Section 8.3.3.12.1.1 Give Battery Status PE_Give_Battery_Status Section 8.3.3.12.2.1 Manufacturer Information Get Manufacturer Information PE_Get_Manufacturer_Info Section 8.3.3.13.1.1 Give Manufacturer Information PE_Give_Manufacturer_Info Section 8.3.3.13.2.1 Country Codes and Information Get Country Codes PE_Get_Country_Codes Section 8.3.3.14.1.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 969 Give Country Codes PE_Give_Country_Codes Section 8.3.3.14.2.1 Get Country Information PE_Get_Country_Info Section 8.3.3.14.3.1 Give Country Information PE_Give_Country_Info Section 8.3.3.14.4.1 Revision Get Revision PE_Get_Revision Section 8.3.3.15.1.1 Give Revision PE_Give_Revision Section 8.3.3.15.2.1 Enter USB DFP Enter USB PE_DEU_Send_Enter_USB Section 8.3.3.16.1.1 UFP Enter USB PE_UEU_Enter_USB_Received Section 8.3.3.16.2.1 Security Request/Response Send Security Request PE_Send_Security_Request Section 8.3.3.17.1.1 Send Security Response PE_Send_Security_Response Section 8.3.3.17.2.1 Security Response Received PE_Security_Response_Received Section 8.3.3.17.3.1 Firmware Update Request/Response Send Firmware Update Request PE_Send_Firmware_Update_Request Section 8.3.3.18.1.1 Send Firmware Update Response PE_Send_Firmware_Update_Response Section 8.3.3.18.2.1 Firmware Update Response Received PE_Firmware_Update_Response_Received Section 8.3.3.18.3.1 Dual-Role Port DFP to UFP Data Role Swap PE_DRS_DFP_UFP_Evaluate_Swap Section 8.3.3.19.1.2 PE_DRS_DFP_UFP_Accept_Swap Section 8.3.3.19.1.3 PE_DRS_DFP_UFP_Change_to_UFP Section 8.3.3.19.1.4 PE_DRS_DFP_UFP_Send_Swap Section 8.3.3.19.1.5 PE_DRS_DFP_UFP_Reject_Swap Section 8.3.3.19.1.6 Table 8.154 Policy Engine States State name Reference Page 970 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 UFP to DFP Data Role Swap PE_DRS_UFP_DFP_Evaluate_Swap Section 8.3.3.19.2.2 PE_DRS_UFP_DFP_Accept_Swap Section 8.3.3.19.2.3 PE_DRS_UFP_DFP_Change_to_DFP Section 8.3.3.19.2.4 PE_DRS_UFP_DFP_Send_Swap Section 8.3.3.19.2.5 PE_DRS_UFP_DFP_Reject_Swap Section 8.3.3.19.2.6 Source to Sink Power Role Swap PE_PRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.3.2 PE_PRS_SRC_SNK_Accept_Swap Section 8.3.3.19.3.3 PE_PRS_SRC_SNK_Transition_to_off Section 8.3.3.19.3.4 PE_PRS_SRC_SNK_Assert_Rd Section 8.3.3.19.3.5 PE_PRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.3.6 PE_PRS_SRC_SNK_Send_Swap Section 8.3.3.19.3.7 PE_PRS_SRC_SNK_Reject_Swap Section 8.3.3.19.3.8 Sink to Source Power Role Swap PE_PRS_SNK_SRC_Evaluate_Swap Section 8.3.3.19.4.2 PE_PRS_SNK_SRC_Accept_Swap Section 8.3.3.19.4.3 PE_PRS_SNK_SRC_Transition_to_off Section 8.3.3.19.4.4 PE_PRS_SNK_SRC_Assert_Rp Section 8.3.3.19.4.5 PE_PRS_SNK_SRC_Source_on Section 8.3.3.19.4.6 PE_PRS_SNK_SRC_Send_Swap Section 8.3.3.19.4.7 PE_PRS_SNK_SRC_Reject_Swap Section 8.3.3.19.4.8 Source to Sink Fast Role Swap PE_FRS_SRC_SNK_Evaluate_Swap Section 8.3.3.19.5.2 PE_FRS_SRC_SNK_Accept_Swap Section 8.3.3.19.5.3 PE_FRS_SRC_SNK_Transition_to_off Section 8.3.3.19.5.4 PE_FRS_SRC_SNK_Assert_Rd Section 8.3.3.19.5.5 PE_FRS_SRC_SNK_Wait_Source_on Section 8.3.3.19.5.6 Sink to Source Fast Role Swap PE_FRS_SNK_SRC_Start_AMS Section 8.3.3.19.6.1 PE_FRS_SNK_SRC_Send_Swap Section 8.3.3.19.6.2 PE_FRS_SNK_SRC_Transition_to_off Section 8.3.3.19.6.3 PE_FRS_SNK_SRC_VBUS_Applied Section 8.3.3.19.6.4 PE_FRS_SNK_SRC_Assert_Rp Section 8.3.3.19.6.5 PE_FRS_SNK_SRC_Source_on Section 8.3.3.19.6.6 Dual-Role Source Port Get Source Capabilities PE_DR_SRC_Get_Source_Cap Section 8.3.3.19.7.1 Dual-Role Source Port Give Sink Capabilities PE_DR_SRC_Give_Sink_Cap Section 8.3.3.19.8.1 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 971 Dual-Role Sink Port Get Sink Capabilities PE_DR_SNK_Get_Sink_Cap Section 8.3.3.19.9.1 Dual-Role Sink Port Give Source Capabilities PE_DR_SNK_Give_Source_Cap Section 8.3.3.19.10.1 Dual-Role Source Port Get Source Capabilities Extended PE_DR_SRC_Get_Source_Cap_Ext Section 8.3.3.19.11.1 Dual-Role Sink Port Give Source Capabilities Extended PE_DR_SNK_Give_Source_Cap_Ext Section 8.3.3.19.12.1 Dual-Role Sink Port Get Sink Capabilities Extended PE_DR_SNK_Get_Sink_Cap_Ext Section 8.3.3.19.13.1 Dual-Role Source Port Give Sink Capabilities Extended PE_DR_SRC_Give_Sink_Cap_Ext Section 8.3.3.19.14.1 Dual-Role Source Port Get Source Information PE_DR_SRC_Get_Source_Info Section 8.3.3.19.15.1 Dual-Role Sink Port Give Source Information PE_DR_SNK_Give_Source_Info Section 8.3.3.19.16.1 USB Type-C VCONN Swap PE_VCS_Send_Swap Section 8.3.3.20.1 PE_VCS_Evaluate_Swap Section 8.3.3.20.2 PE_VCS_Accept_Swap Section 8.3.3.20.3 PE_VCS_Reject_Swap Section 8.3.3.20.4 PE_VCS_Wait_For_VCONN Section 8.3.3.20.5 PE_VCS_Turn_Off_VCONN Section 8.3.3.20.6 PE_VCS_Turn_On_VCONN Section 8.3.3.20.7 PE_VCS_Send_Ps_Rdy Section 8.3.3.20.8 PE_VCS_Force_VCONN Section 8.3.3.20.9 Initiator Structured VDM Initiator to Port Structured VDM Discover Identity PE_INIT_PORT_VDM_Identity_Request Section 8.3.3.21.1.1 PE_INIT_PORT_VDM_Identity_ACKed Section 8.3.3.21.1.2 PE_INIT_PORT_VDM_Identity_NAKed Section 8.3.3.21.1.3 Initiator Structured VDM Discover SVIDs PE_INIT_VDM_SVIDs_Request Section 8.3.3.21.2.1 PE_INIT_VDM_SVIDs_ACKed Section 8.3.3.21.2.2 PE_INIT_VDM_SVIDs_NAKed Section 8.3.3.21.2.3 Initiator Structured VDM Discover Modes PE_INIT_VDM_Modes_Request Section 8.3.3.21.3.1 PE_INIT_VDM_Modes_ACKed Section 8.3.3.21.3.2 PE_INIT_VDM_Modes_NAKed Section 8.3.3.21.3.3 Table 8.154 Policy Engine States State name Reference Page 972 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Initiator Structured VDM Attention PE_INIT_VDM_Attention_Request Section 8.3.3.21.4.1 Responder Structured VDM Responder Structured VDM Discovery Identity PE_RESP_VDM_Get_Identity Section 8.3.3.22.1.1 PE_RESP_VDM_Send_Identity Section 8.3.3.22.1.2 PE_RESP_VDM_Get_Identity_NAK Section 8.3.3.22.1.3 Responder Structured VDM Discovery SVIDs PE_RESP_VDM_Get_SVIDs Section 8.3.3.22.2.1 PE_RESP_VDM_Send_SVIDs Section 8.3.3.22.2.2 PE_RESP_VDM_Get_SVIDs_NAK Section 8.3.3.22.2.3 Responder Structured VDM Discovery Modes PE_RESP_VDM_Get_Modes Section 8.3.3.22.3.1 PE_RESP_VDM_Send_Modes Section 8.3.3.22.3.2 PE_RESP_VDM_Get_Modes_NAK Section 8.3.3.22.3.3 Receiving a Structured VDM Attention PE_RCV_VDM_Attention_Request Section 8.3.3.22.4.1 DFP Structured VDM DFP Structured VDM Mode Entry PE_DFP_VDM_Mode_Entry_Request Section 8.3.3.23.1.1 PE_DFP_VDM_Mode_Entry_ACKed Section 8.3.3.23.1.2 PE_DFP_VDM_Mode_Entry_NAKed Section 8.3.3.23.1.3 DFP Structured VDM Mode Exit PE_DFP_VDM_Mode_Exit_Request Section 8.3.3.23.2.1 PE_DFP_VDM_Mode_Exit_ACKed Section 8.3.3.23.2.2 UFP Structure VDM UFP Structured VDM Enter Mode PE_UFP_VDM_Evaluate_Mode_Entry Section 8.3.3.24.1.1 PE_UFP_VDM_Mode_Entry_ACK Section 8.3.3.24.1.2 PE_UFP_VDM_Mode_Entry_NAK Section 8.3.3.24.1.3 UFP Structured VDM Exit Mode PE_UFP_VDM_Mode_Exit Section 8.3.3.24.2.1 PE_UFP_VDM_Mode_Exit_ACK Section 8.3.3.24.2.2 PE_UFP_VDM_Mode_Exit_NAK Section 8.3.3.24.2.3 Table 8.154 Policy Engine States State name Reference Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 973 Cable Plug Specific Cable Ready PE_CBL_Ready Section 8.3.3.25.1.1 Mode Entry PE_CBL_Evaluate_Mode_Entry Section 8.3.3.25.4.1.1 PE_CBL_Mode_Entry_ACK Section 8.3.3.25.4.1.2 PE_CBL_Mode_Entry_NAK Section 8.3.3.25.4.1.3 Mode Exit PE_CBL_Mode_Exit Section 8.3.3.25.4.2.1 PE_CBL_Mode_Exit_ACK Section 8.3.3.25.4.2.2 PE_CBL_Mode_Exit_NAK Section 8.3.3.25.4.1.3 Cable Soft Reset PE_CBL_Soft_Reset Section 8.3.3.25.2.1.1 Cable Hard Reset PE_CBL_Hard_Reset Section 8.3.3.25.2.2.1 DFP/VCONN Source Soft Reset or Cable Reset PE_DFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.3.1 PE_DFP_VCS_CBL_Send_Cable_Reset Section 8.3.3.25.2.3.2 UFP/VCONN Source Soft Reset or Cable Reset PE_UFP_VCS_CBL_Send_Soft_Reset Section 8.3.3.25.2.4.1 Source Startup Structured VDM Discover Identity PE_SRC_VDM_Identity_Request Section 8.3.3.25.3.1 PE_SRC_VDM_Identity_ACKed Section 8.3.3.25.3.2 PE_SRC_VDM_Identity_NAKed Section 8.3.3.25.3.3 EPR Mode Source EPR Mode Entry PE_SRC_Evaluate_EPR_Mode_Entry Section 8.3.3.26.1.1 PE_SRC_EPR_Mode_Entry_Ack Section 8.3.3.26.1.2 PE_SRC_EPR_Mode_Discover_Cable Section 8.3.3.26.1.3 PE_SRC_EPR_Mode_Evaluate_Cable_EPR Section 8.3.3.26.1.4 PE_SRC_EPR_Mode_Entry_Succeeded Section 8.3.3.26.1.5 PE_SRC_EPR_Mode_Entry_Failed Section 8.3.3.26.1.6 Sink EPR Mode Entry PE_SNK_Send_EPR_Mode_Entry Section 8.3.3.26.2.1 PE_SNK_EPR_Mode_Wait_For_Response Section 8.3.3.26.2.2 Source EPR Mode Exit PE_SRC_Send_EPR_Mode_Exit Section 8.3.3.26.3.1 PE_SRC_EPR_Mode_Exit_Received Section 8.3.3.26.3.2 Table 8.154 Policy Engine States State name Reference Page 974 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Sink EPR Mode Exit PE_SNK_Send_EPR_Mode_Exit Section 8.3.3.26.4.1 PE_SNK_EPR_Mode_Exit_Received Section 8.3.3.26.4.2 BIST BIST Carrier Mode PE_BIST_Carrier_Mode Section 8.3.3.27.1.1 BIST Carrier Mode PE_BIST_Test_Mode Section 8.3.3.27.2.1 BIST Shared Capacity Test Mode PE_BIST_Shared_Capacity_Test_Mode Section 8.3.3.27.3.1 USB Type-C referenced states ErrorRecovery Section 8.3.3.28.1 Table 8.154 Policy Engine States State name Reference
9 - States and Status Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 975)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 975 9 States and Status Reporting 9.1 Overview This chapter describes the Status reporting mechanisms for devices with data connections (e.g., D+/D- and or SSTx+/- and SSRx+/-). It also describes the corresponding USB state a device that supports USB PD Shall transition to as a result of changes to the USB PD state that the device is in. This chapter does not define the System Policy or the System Policy Manager. That is defined in [UCSI]. In addition, the Policies themselves are not described here; these are left to the implementers of the relevant products and systems to define. All PD Capable USB (PDUSB) Devices Shall report themselves as self-powered devices (over USB) when plugged into a PD capable Port even if they are entirely powered from VBUS. However, there are some differences between PD and [USB 2.0] / [USB 3.2]; for example, the presence of VBUS alone does not mean that the device (Consumer) moves from the USB Attached State to the USB Powered State. Similarly, the removal of VBUS alone does not move the device (Consumer) from any of the USB states to the USB Attached State. See Section 9.1.2, "Mapping to USB Device States" for details. PDUSB Devices Shall follow the PD requirements when it comes to suspend (see Section 6.4.1.2.1.2, "USB Suspend Supported"), configured, and operational power. The PD requirements when the device is configured or operational are defined in this section (see Table 9.4, "PD Consumer Port Descriptor"). Note: The power requirements reported in the PD Consumer Port descriptor of the device Shall override the power draw reported in the bMaxPower field in the configuration descriptor. A PDUSB Device Shall report zero in the bMaxPower field after successfully negotiating a mutually agreeable Explicit Contract and Shall disconnect and re-enumerate when it switches operation back to operating in standard [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2]. When operating in [USB 2.0], [USB 3.2], [USB Type-C 2.4] or [USBBC 1.2] mode it Shall report its power draw via the bMaxPower field. Each Provider and Consumer will have their own Local Policies which operate between Port Partners. An example of a typical PD system is shown in Figure 9.1, "Example PD Topology". This example consists of a Provider, Consumer/Providers and Consumers connected together in a tree topology. Between directly connected devices there is both a flow of Power and also Communication consisting of both Status and Control information. Page 976 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.1 Example PD Topology Consumer Consumer Consumer/ Provider Consumer/ Provider Provider AC/Battery AC/Battery Power PD Communication P/C P/C P/C P/C Provider/Consumer Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 977 Figure 9.2, "Mapping of PD Topology to USB" shows how this same topology can be mapped to USB. Figure 9.2 Mapping of PD Topology to USB Device Device Device Root Hub AC/Battery AC/Battery Power PD Communication Hub Page 978 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 In a USB based system, policy is managed by the host and communication of system level policy information is via standard USB data line communication. This is a separate mechanism to the USB Power Delivery VBUS protocol which is used to manage Local Policy. When USB Communication is used, status information and control requests are passed directly between the System Policy Manager (SPM) on the host and the Provider or Consumer. See Figure 9.3, "Use of SPM in the PD System". Figure 9.3 Use of SPM in the PD System Status information comes from a Provider or Consumer to the SPM so it can better manage the resources on the host and provide feedback to the end user. Real systems will be a mixture of devices which in terms of power management support might have implemented PD, [USB 2.0], [USB 3.2], [USB4], [USB Type-C 2.4] or [USBBC 1.2] or they might even just be non-compliant “power sucking devices”. The level of communication of system status to the SPM will therefore not necessarily be comprehensive. The aim of the status mechanisms described here is to provide a mechanism whereby each connected entity in the system provides as much information as possible on the status of itself. Information described in this section that is communicated to the SPM is as follows:  Versions of USB Type-C®, PD and BC supported.  Capabilities as a Provider/Consumer.  Current operational state of each Port e.g. Standard, USB Type-C Current, BC, PD and Negotiated power level.  Status of AC or Battery Power for each PDUSB Device in the system. The SPM can Negotiate with Providers or Consumers in the system in order to request a different Local Policy, or to request the amount of power to be delivered by the Provider to the Consumer. Any change in Local Policy could Device Device Device Host (SPM) AC/Battery AC/Battery Power PD Communication USB Communication Hub Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 979 trigger a Re-negotiation of the Explicit Contract, using USB Power Delivery protocols, between a directly connected Provider and Consumer. A change in how much power is available can, for example, cause a Re-negotiation. 9.1.1 PDUSB Device and Hub Requirements All PDUSB Devices Shall return all relevant descriptors mentioned in this chapter. PDUSB Hubs Shall also support a PD bridge as defined in [UCSI]. Page 980 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.2 Mapping to USB Device States As mentioned in Section 9.1, "Overview" a PDUSB Device reports itself as a self-powered device. However, the device Shall determine whether or not it is in the USB Attached State or USB Powered States as described in Figure 9.4, "USB Attached to USB Powered State Transition", Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" and Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" All other USB states of the PDUSB Device Shall be as described in Chapter 9 of [USB 2.0] and [USB 3.2]. Figure 9.4, "USB Attached to USB Powered State Transition" shows how a PDUSB Device determines when to transition from the USB Attached State to the USB Powered State. USB Type-C Dead Battery operation does not require special handling since the default state at Attach or after a Hard Reset is that the USB Device is a Sink. Figure 9.4 USB Attached to USB Powered State Transition Figure 9.5, "Any USB State to USB Attached State Transition (When operating as a Consumer)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Consumer. A PDUSB Device determines that it is performing a Power Role Swap as described in Section 8.3.3.19.3, "Policy Engine in Source to Sink Power Role Swap State Diagram" and Section 8.3.3.19.4, "Policy Engine in Sink to Source Power Role Swap State Diagram". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present No Yes Can enumerate? Yes Device is a Source? Attached Sink? USB Attached Yes Device in Sink Mode No Negotiate enough Power? No USB Powered No No Yes Device in Source Mode (5V) Yes Hard Reset Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 981 Figure 9.5 Any USB State to USB Attached State Transition (When operating as a Consumer) Figure 9.6, "Any USB State to USB Attached State Transition (When operating as a Provider)" shows how a PDUSB Device determines when to transition from the USB Powered State to the USB Attached State when the device is a Provider. Figure 9.6 Any USB State to USB Attached State Transition (When operating as a Provider) Figure 9.7, "Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap)" shows how a PDUSB Device using the USB Type-C connector determines when to transition from the USB Powered State to the USB Attached State after a Data Role Swap has been performed i.e., it has just changed from operation as a PDUSB Host to operation as a PDUSB Device. The Data Role Swap is described in Section 6.3.9, "DR_Swap Message". A Hard Reset will also return a Sink acting as a PDUSB Host to PDUSB Device operation as described in Section 6.8.3, "Hard Reset". See Section 7.1.5, "Response to Hard Resets" for additional information on device behavior during Hard Resets. VBUS Present Yes No Swapping Power Roles? Any USB State USB Attached Yes No Hard Reset and Can Operate Hard Reset and Can’t Operate Hard Reset and Bus Powered Lack of PD comms? No Yes Any USB State USB Attached Local Power Source Lost Hard Reset Page 982 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 9.7 Any USB State to USB Attached State Transition (After a USB Type-C Data Role Swap) VBUS Present Yes Swapping Data Roles? Any USB State USB Attached No Yes Hard Reset Changes Data Role Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 983 9.1.3 PD Software Stack Figure 9.8, "Software stack on a PD aware OS" gives an example of the software stack on a PD aware OS. In this stack we are using the example of a system with an xHCI based controller. The USB Power Delivery hardware May or May Not be a part of the xHC. Figure 9.8 Software stack on a PD aware OS Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager Page 984 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.1.4 PDUSB Device Enumeration As described earlier, a PDUSB Device acts as a self-powered device with some caveats with respect to how it transitions from the USB Attached State to USB Powered State. Figure 9.9, "Enumeration of a PDUSB Device" gives a high-level overview of the enumeration steps involved due to this change. A PDUSB Device will first (Step1) interact with the Power Delivery hardware and the Local Policy manager to determine whether or not it can get sufficient power to enumerate/operate. PD is likely to have established a Explicit Contract prior to enumeration. The SPM will be notified (Step 2) of the result of this Negotiation between the Power Delivery hardware and the PDUSB Device. After successfully negotiating a mutually agreeable Explicit Contract the device will signal a connect to the xHC. The standard USB enumeration process (Steps 3, 4 and 5) is then followed to load the appropriate driver for the function(s) that the PDUSB Device exposes. Figure 9.9 Enumeration of a PDUSB Device If a PDUSB Device cannot perform its intended function with the amount of power that it can get from the Port it is connected to, then the host system Should display a notification (on a PD aware OS) about the failure to provide sufficient power to the device. In addition, the device Shall follow the requirements listed in Section 8.2.5.2.1, "Local device handling of mismatch". Client Drivers Client Drivers Client Drivers USB Driver Interface Composite Class Driver Client Drivers USB Driver Interface Hub Driver Internal Hub/Host Interface Host Controller Driver xHC Interface Host Controller PD xface Power Delivery System Policy Manager 5 4 3 2 1 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 985 9.2 PD Specific Descriptors A PDUSB Device Shall return all relevant descriptors mentioned in this section. The device Shall return its capability descriptors as part of the device's Binary Object Store (BOS) descriptor set. Table 9.1, "USB Power Delivery Type Codes" lists the type of PD device capabilities. Table 9.1 USB Power Delivery Type Codes Capability Code Value Description POWER_DELIVERY_CAPABILITY 06H Defines the various PD Capabilities of this device BATTERY_INFO_CAPABILITY 07H Provides information on each Battery supported by the device PD_CONSUMER_PORT_CAPABILITY 08H The Consumer characteristics of a Port on the device PD_PROVIDER_PORT_CAPABILITY 09H The Provider characteristics of a Port on the device Page 986 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.1 USB Power Delivery Capability Descriptor Table 9.2, "USB Power Delivery Capability Descriptor" details the fields in the USB POWER_DELIVERY_CAPABILITY Descriptor. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: POWER_DELIVERY_CAPABILITY 3 bReserved 1 Reserved Shall be set to zero. 4 bmAttributes 4 Bitmap Bitmap encoding of supported device level features. A value of one in a bit location indicates a feature is supported; a value of zero indicates it is not supported. Encodings are: Bit Description 0 Reserved. Shall be set to zero. 1 Battery Charging. This bit Shall be set to one to indicate this device supports [USBBC 1.2] as per the value reported in the bcdBCVersion field. 2 USB Power Delivery. This bit Shall be set to one to indicate this device supports the USB Power Delivery Specification as per the value reported in the bcdPDVersion field. 3 Provider. This bit Shall be set to one to indicate this device is capable of providing power. This field is only Valid if Bit 2 is set to one. 4 Consumer. This bit Shall be set to one to indicate that this device is a consumer of power. This field is only Valid if Bit 2 is set to one. 5 This bit Shall be set to 1 to indicate that this device supports the feature CHARGING_POLICY. Note: Supporting the CHARGING_POLICY feature does not require a BC or PD mechanism to be implemented. 6 USB Type-C Current. This bit Shall be set to one to indicate this device supports power capabilities defined in[USB Type-C 2.4] as per the value reported in the bcdUSBTypeCVersion field 7 Reserved. Shall be set to zero. 15:8 bmPowerSource. At least one of the following bits 8, 9 and 14 Shall be set to indicate which power sources are supported. Bit Description 8 AC Supply 9 Battery 10 Other 13:11 NumBatteries. This field Shall only be Valid when the Battery field is set to one and Shall be used to report the number of batteries in the device. 14 Uses VBUS 15 Reserved and Shall be set to zero. 13:16 Reserved. Shall be set to zero. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 987 9.2.2 Battery Info Capability Descriptor A PDUSB Device Shall support the capability descriptor shown in Table 9.3, "Battery Info Capability Descriptor" if it reported that one of its power sources was a Battery in the bmPowerSource field in its Power Deliver Capability Descriptor. It Shall return one BATTERY_INFO_CAPABILITY Descriptor per Battery it supports. 8 bcdBCVersion 2 BCD Battery Charging Specification Release Number in Binary-Coded Decimal (e.g., V1.20 is 120H). This field Shall only be Valid if the device indicates that it supports [USBBC 1.2] in the bmAttributes field. 10 bcdPDVersion 2 BCD USB Power Delivery Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports PD in the bmAttributes field. 12 bcdUSBTypeCVersion 2 BCD USB Type-C Specification Release Number in Binary-Coded Decimal. This field Shall only be Valid if the device indicates that it supports USB Type-C in the bmAttributes field. Table 9.3 Battery Info Capability Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: BATTERY_INFO_CAPABILITY 3 iBattery 1 Index Index of string descriptor Shall contain the user-friendly name for this Battery. 4 iSerial 1 Index Index of string descriptor Shall contain the Serial Number String for this Battery. 5 iManufacturer 1 Index Index of string descriptor Shall contain the name of the Manufacturer for this Battery. 6 bBatteryId 1 Number Value Shall be used to uniquely identify this Battery in status Messages. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 dwChargedThreshold 4 mWh Shall contain the Battery charge value above which this Battery is considered to be fully charged but not necessarily “topped off.” 12 dwWeakThreshold 4 mWh Shall contain the minimum charge level of this Battery such that above this threshold, a device can be assured of being able to power up successfully (see [USBBC 1.2]). 16 dwBatteryDesignCapacity 4 mWh Shall contain the design capacity of the Battery. 20 dwBatteryLastFullchargeCapacity 4 mWh Shall contain the maximum capacity of the Battery when fully charged. Table 9.2 USB Power Delivery Capability Descriptor Offset Field Size Value Description Page 988 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.2.3 PD Consumer Port Capability Descriptor A PDUSB Device Shall support the PD_CONSUMER_PORT_CAPABILITY descriptor shown in Table 9.4, "PD Consumer Port Descriptor" if it is a Consumer. Table 9.4 PD Consumer Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_CONSUMER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Consumer Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 wMinVoltage 2 Number Shall contain the minimum voltage in 50mV units that this Consumer is capable of operating at. 8 wMaxVoltage 2 Number Shall contain the maximum voltage in 50mV units that this Consumer is capable of operating at. 10 wReserved 2 Number Reserved and Shall be set to zero. 12 dwMaxOperatingPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw when it is in a steady state operating mode. 16 dwMaxPeakPower 4 Number Shall contain the maximum power in 10mW units this Consumer can draw for a short duration of time (dwMaxPeakPowerTime) before it falls back into a steady state. 20 dwMaxPeakPowerTime 4 Number Shall contain the time in 100ms units that this Consumer can draw peak current. A device Shall set this field to 0xFFFF if this value is unknown. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 989 9.2.4 PD Provider Port Capability Descriptor A PDUSB Device Shall support the PD_PROVIDER_PORT_CAPABILITY descriptor shown in Table 9.5, "PD Provider Port Descriptor" if it is a Provider. Table 9.5 PD Provider Port Descriptor Offset Field Size Value Description 0 bLength 1 Number Size of descriptor 1 bDescriptorType 1 Constant DEVICE CAPABILITY Descriptor type 2 bDevCapabilityType 1 Constant Capability type: PD_PROVIDER_PORT_CAPABILITY 3 bReserved 1 Number Reserved and Shall be set to zero. 4 bmCapabilities 2 Bitmap Capability: This field Shall indicate the specification the Provider Port will operate under. Bit Description 0 Battery Charging (BC) 1 USB Power Delivery (PD) 2 USB Type-C Current 15:3 Reserved and Shall be set to zero. 6 bNumOfPDObjects 1 Number Shall indicate the number of Power Data Objects. 7 bReserved 1 Number Reserved and Shall be set to zero. 8 wPowerDataObject1 4 Bitmap Shall contain the first Power Data Object supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. ... ... ... ... ... 4*(N+1) wPowerDataObjectN 4 Bitmap Shall contain the 2nd and subsequent Power Data Objects supported by this Provider Port. See Section 6.4.1, "Capabilities Message" for details of the Power Data Objects. Page 990 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.3 PD Specific Requests and Events A PDUSB Device that is compliant to this specification Shall support the Battery related requests if it has a Battery. A PDUSB Hub that is compliant to this specification Shall support a USB PD Bridge as described in [UCSI] irrespective of whether the PDUSB Hub is a Provider, a Consumer, or both. 9.3.1 PD Specific Requests PD defines requests to which PDUSB Devices Shall respond as outlined in Table 9.6, "PD Requests". All Valid requests in Table 9.6, "PD Requests" Shall be implemented by PDUSB Devices. Table 9.7, "PD Request Codes" gives the bRequest values for Commands that are not listed in the hub/device framework chapters of [USB 2.0], [USB 3.2]. Table 9.8, "PD Feature Selectors" gives the Valid feature selectors for the PD class. Refer to Section 9.4.2.1, "BATTERY_WAKE_MASK Feature Selector", and Section 9.4.2.2, "CHARGING_POLICY Feature Selector" for a description of the features. Table 9.6 PD Requests Request bmRequestType bRequest wValue wIndex wLength Data GetBatteryStatus 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status SetPDFeature 00000000B set_feature Feature Selector Feature Specific Zero None Table 9.7 PD Request Codes bRequest Value GET_BATTERY_STATUS 21 Table 9.8 PD Feature Selectors Feature Selector Recipient Value BATTERY_WAKE_MASK Device 40 CHARGING_POLICY Device 54 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 991 9.4 PDUSB Hub and PDUSB Peripheral Device Requests 9.4.1 GetBatteryStatus The request shown in Table 9.9, "Get Battery Status Request" returns the current status of the Battery in a PDUSB Hub/Peripheral, with Battery Status information as shown in Table 9.10, "Battery Status Structure". Table 9.9 Get Battery Status Request bmRequestType bRequest wValue wIndex wLength Data 10000000B GET_BATTERY_STATUS Zero Battery ID Eight Battery Status Table 9.10 Battery Status Structure Offset Field Size Value Description 0 bBatteryAttributes 1 Number Shall indicate whether a Battery is installed and whether this is charging or discharging. Value Description 0 There is no Battery 1 The Battery is charging 2 The Battery is discharging 3 The Battery is neither discharging nor charging 255...4 Reserved and Shall Not be used 1 bBatterySOC 1 Number Shall indicate the Battery State of Charge given as percentage value from Battery Remaining Capacity. 2 bBatteryStatus 1 Number If a Battery is present Shall indicate the present status of the Battery. Value Description 0 No error 1 Battery required and not present 2 Battery non-chargeable/wrong chemistry 3 Over-temp shutdown 4 Over-voltage shutdown 5 Over-current shutdown 6 Fatigued Battery 7 Unspecified error 255...8 Reserved and Shall Not be used Page 992 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 If wValue or wLength are not as specified above, then the behavior of the PDUSB Device is not specified. If wIndex refers to a Battery that does not exist, then the PDUSB Device Shall respond with a Request Error. If the PDUSB Device is not configured, the PDUSB Hub's response to this request is undefined. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. 9.4.2 SetPDFeature The request shown in Table 9.11, "Set PD Feature" sets the value requested in the PDUSB Hub/Peripheral. Setting a feature enables that feature or starts a process associated with that feature; see Table 9.8, "PD Feature Selectors" for the feature selector definitions. Features that May be set with this request are:  BATTERY_WAKE_MASK.  CHARGING_POLICY. 3 bRemoteWakeCapStatus 1 Bitmap If the device supports remote wake, then the device Shall support Battery Remote wake events. The default value for the Remote wake events Shall be turned off (set to zero) and can be enable/disabled by the host as required. If set to one the device Shall generate a wake event when a change of status occurs. See Section 9.4.2, "SetPDFeature" for more details. Value Description 0 Battery present event 1 Charging flow 2 Battery error 7:3 Reserved and Shall be set to zero 4 wRemainingOperatingTime 2 Number Shall contain the operating time (in minutes) until the Weak Battery threshold is reached, based on Present Battery Strength and the device's present operational power needs. Note: This value Shall exclude any additional power re- ceived from charging. A Battery that is not capable of returning this information Shall return a value of 0xFFFF. 6 wRemainingChargeTime 2 Number Shall contain the remaining time (in minutes) until the Charged Battery threshold is reached based on Present Battery Strength, charging power and the device's present operational power needs. Value Shall only be Valid if the Charging Flow is "Charging". A Battery that is not capable of returning this information Shall return a value of 0xFFFF. Table 9.11 Set PD Feature bmRequestType bRequest wValue wIndex wLength Data 00000000B set_ feature Feature Selector Feature Specific Zero None Table 9.10 Battery Status Structure Offset Field Size Value Description Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 993 9.4.2.1 BATTERY_WAKE_MASK Feature Selector When the feature selector is set to BATTERY_WAKE_MASK, then the wIndex field is structured as shown in Table 9.12, "Battery Wake Mask". The SPM May Enable or Disable the wake events associated with one or more of the above events by using this feature. If the PDUSB Hub is not configured, the PDUSB Hub's response to this request is undefined. Table 9.12 Battery Wake Mask Bit Description 0 Battery Present: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery has been inserted. 1 Charging Flow: When this bit is set then the PDUSB Device Shall generate a wake event if it detects that a Battery switched from charging to discharging or vice versa. 2 Battery Error: When this bit is set then the PDUSB Device Shall generate a wake event if the Battery has detected an error condition. 15:3 Reserved and Shall Not be used Page 994 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 9.4.2.2 CHARGING_POLICY Feature Selector When the feature selector is set to CHARGING_POLICY, the wIndex field Shall be set to one of the values defined in Table 9.13, "Charging Policy Encoding". If the device is using USB Type-C Current above the default value or is using PD then this feature setting has no effect and the rules for power levels specified in the [USB Type-C 2.4] or USB PD specifications Shall apply. This is a Valid Command for the PDUSB Hub/Peripheral in the Address or Configured USB states. Further, it is only Valid if the device reports a USB PD capability descriptor in its BOS descriptor and Bit 5 of the bmAttributes in that descriptor is set to 1. The device will go back to the wIndex default value of 0 whenever it is reset. Table 9.13 Charging Policy Encoding Value Description 00H The device Shall follow the default current limits as defined in the USB 2.0 or USB 3.1 specification, or as negotiated through other USB mechanisms such as BC. This is the default value. 01H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCHPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 02H The Device May draw additional power during the unconfigured and suspend states for the purposes of charging. For charging the device itself, the device Shall limit its current draw to the higher of these two values: ICCLPF as defined in the USB 2.0 or USB 3.1 specification, regardless of its USB state. Current limit as negotiated through other USB mechanisms such as BC. 03H The device Shall Not consume any current for charging the device itself regardless of its USB state. 04H-FFFFH Reserved and Shall Not be used
10 - Power Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (Page 995)
Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 995 10 Power Rules 10.1 Introduction The flexibility of power provision on USB Type-C® is expected to lead to power adapter re-use and the increasingly widespread provision of USB power outlets in domestic and public places and in transport of all kinds. Environmental considerations could result in unbundled power adapters. Rules are needed to avoid incompatibility between the Sources and the Sinks they are used to power, in order to avoid user confusion and to meet user expectations. This section specifies a set of rules that Sources and Sinks Shall follow. These rules provide a simple and consistent user experience. The PDP Rating is a manufacturer declared value placed on packaging to help the user understand the capabilities of a Charger or the size of Charger required to power their device. For PDP values of 10W and above the PDP Shall be declared as an integer number of Watts. For PDP values less than 10W, the PDP Shall be declared in increments of 0.5W. The Source Power Rules define a PDP to provide a simple way to tell the user about the capabilities of their power adapter or device. PDP Rating is akin to the wattage rating of a light bulb - bigger numbers mean more capability. The Sink Power Rules define a PDP to provide a simple way to tell the user which Sources will provide adequate power for their Sink. 10.2 Source Power Rules The Source Power Rules defined in this section include both Normative and Optional rules. For all of the defined rules, the capabilities a Source exposes are based on the Port Maximum PDP, or if power constrained, the Port Present PDP of the Port. For a Guaranteed Capability Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Maximum PDP and Mode of operation (i.e., SPR Mode or EPR Mode). For a Managed Capability Port, except before the First Explicit Contract or before the Explicit Contract after the Port Present PDP changes on a Shared Capacity Charger Port, the Source Shall always include in every Source_Capabilities or EPR_Source_Capabilities Message sent to a Sink all the (A)PDOs that are defined by the Normative (and Optional when implemented) rules based on the Port’s Port Present PDP and Mode of operation (i.e., SPR Mode or EPR Mode). After the First Explicit Contract, this requirement assures that the attached Sink will always know what voltages (or voltage modes) are presently available from the Source. In order to meet the expectations of the user, the Maximum Current/Power in the Source Capabilities PDO or APDO for Sources with a PDP Rating of x Watts Shall be as follows:  Maximum current for Normative and Optional Fixed Supply/Variable Supply PDOs Shall be either RoundUp(x/voltage) or RoundDown(x/voltage) to the nearest 10mA.  Maximum current for SPR Programmable Power Supply APDOs Shall be as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". Note: When the Constant Power bit is set in the APDO, the programmable power supply's output current is as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" however the programmable power supply will limit its output current so that the product of its actual output voltage times the output current does not exceed the PDP.  If a 9V Prog, 15V Prog or 20V Prog Programmable Power Supply APDO is Advertised when not required by Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP", then the maximum current Shall be RoundDown (x/Prog Voltage) to the nearest 50mA. When the PPS Power Limited bit is clear the Source Shall provide this current at Maximum Voltage.  Maximum power for Optional Battery Supply PDOs Shall be ≤ x. Page 996 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.1 Source Power Rule Considerations The Source Power Rules are designed to:  Ensure the PDP Rating (PDP) of an adapter specified in watts explicitly defines the voltages and currents at each voltage the adapter supports.  Ensure that adapters with a large PDP Ratings are always capable of providing the power to devices designed for use with adapters with a smaller PDP Rating.  Enable an ecosystem of adapters that are inter-operable with the devices in the ecosystem. The considerations that lead to the Source Power Rules are based are summarized in Table 10.1, "Considerations for Sources". Table 10.1 Considerations for Sources Considerations Rationale Consequence Simple to identify capability A user going into an electronics retailer knows what they need Cannot have a complex identification scheme Higher power Sources are a superset of smaller ones Bigger is always better in user’s eyes – don’t want a degradation in performance Higher power Sources do everything smaller ones do Unambiguous Source definitions Sources with the same power rating but different VI combinations might not inter- operate To avoid user confusion, any given power rating has a single definition A range of power ratings Users and companies will want freedom to pick appropriate Source ratings Fixed profiles at specific power levels don’t provide adequate flexibility, e.g., profiles as defined in previous versions of PD. 5V@3A USB Type-C Source is defined by [USB Type-C 2.4] 5V@3A USB Type-C Source is considered All > 15W adapters must support 5V@3A or superset consideration is violated Maximize 3A cable utilization 3A cables will be ubiquitous Increase to maximum voltage (20V) before increasing current beyond 3A Optimize voltage rail count More rails are a higher burden for Sources, particularly in terms of testing 5V is a basic USB requirement. 48V provides the maximum capability. Some Sources are not able to provide significant power Some small Battery-operated Sources e.g., mobile devices, are able to provide more power directly from their Battery than from a regulated 5V supply In addition to the minimal 5V Advertisements are able to Advertise more power from their Battery Some Sources share power between multiple Ports (Hubs and multi-Port Chargers) Hubs and multi-port Chargers have to be supported See Section 10.3, "Sink Power Rules" Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 997 10.2.2 Normative Voltages and Currents The voltages and currents an SPR Source with a PDP Rating of x Watts Shall support are as defined in Table 10.2, "SPR Normative Voltages and Minimum Currents". Table 10.2 SPR Normative Voltages and Minimum Currents Port Maximum PDP Rating (W) 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS 0.5 ≤ x ≤ 15 (PDP/5)A3 - - - - 15 < x ≤ 27 3A2 (PDP/9)A3 - - - 27 < x ≤ 45 3A2 3A2 (PDP/15)A3 - (9V – 15V):  (15V Fixed Supply Max Current) A 45 < x ≤ 60 3A2 3A2 3A2 (PDP/20)A3 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A 60 < x ≤ 100 3A2 3A2 3A2 (PDP/20)A1, 3 (9V – 15V):  (15V Fixed Supply Max Current) A4, 5 (15V – 20V):  (20V Fixed Supply Max Current) A1, 5 1) Requires a 5A cable. 2) The Fixed Supply PDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. Requires a 5A cable if over 3A is Advertised. 3) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 4) SPR AVS current for this voltage range is the maximum current as Advertised by the 15V Fixed Supply PDO. This current can be higher than 3A (refer to Note 2). Requires a 5A cable if over 3A is Advertised. 5) The Sink is allowed to request up to the 20V Fixed Supply Max Current when the requested voltage is 15.0V. Page 998 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 SPR Managed Capability Ports when power constrained are defined to offer Valid (A)PDOs based on the port's Port Maximum PDP (as per Table 10.2, "SPR Normative Voltages and Minimum Currents") at lower Port Present PDP (as per Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP") because these voltages would otherwise be available if the Managed Capability Port power hadn't been constrained. Table 10.3 SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP Port Present PDP (W) 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS with Max Voltage of 15V or 20V per Table 10.26 5 < x ≤ 15 (PDP/5)A3 (PDP/9)A3,7, 8 (PDP/15)A3,7,8 (PDP/20)A3,7,8 (9V – 15V):  (15V Fixed Supply Max Current) A4, 6, 8 (15V – 20V):  (20V Fixed Supply Max Current) A6,8 15 < x ≤ 27 3A2 (PDP/9)A3 (PDP/15)A3,7 (PDP/20)A3,7 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A6 27 < x ≤ 45 3A2 3A2 (PDP/15)A3 45 < x ≤ 60 3A2 3A2 3A2 (PDP/20)A3 (9V – 15V):  (15V Fixed Supply Max Current) A4 (15V – 20V):  (20V Fixed Supply Max Current) A 60 < x ≤ 100 3A2 3A2 3A2 (PDP/20)A1, 3 (9V – 15V):  (15V Fixed Supply Max Current) A4, 5 (15V – 20V):  (20V Fixed Supply Max Current) A1, 5 1) Requires a 5A cable. 2) The Fixed Supply PDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. Requires a 5A cable if over 3A is Advertised. 3) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 4) SPR AVS current for this voltage range is the maximum current as Advertised by the 15V Fixed Supply PDO. This current can be higher than 3A (refer to Note 2). Requires a 5A cable if over 3A is Advertised. 5) The Sink is allowed to request up to the 20V Fixed Supply Max Current when the requested voltage is 15.0V. 6) The Max Voltage for SPR AVS is what is allowed by Table 10.2, "SPR Normative Voltages and Minimum Currents" based on the port's Port Maximum PDP. 7) This SPR Fixed Supply voltage is only available if allowed by Table 10.2, "SPR Normative Voltages and Minimum Currents" based on the port's Port Maximum PDP. 8) SPR Sources May offer (A)PDOs at this Port Present PDP Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 999 In reference to Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP", Table 10.4, "SPR Source Port Present PDP less than Port Maximum PDP Examples" gives examples of which SPR capabilities are Advertised based on Port Present PDP on a Managed Capability Port and the port's Port Maximum PDP and cable's current rating. Table 10.4 SPR Source Port Present PDP less than Port Maximum PDP Examples Port Maximum PDP and Cable Rating Port Present PDP Offers 5V Fixed 9V Fixed 15V Fixed 20V Fixed SPR AVS 80W / 5A 65W 3A1 3A1 3A1 3.25A 9V – 15V: 3A 15V – 20V: 3.25A 80W / 5A 40W 3A1 3A1 2.67A 2A 9V – 15V: 2.67A 15V – 20V: 2A 80W / 3A 40W 3A1 3A 2.67A 2A 9V – 15V: 2.67A 15V – 20V: 2A 40W / 5A 40W 3A1 3A1 2.67A Not Offered 9V – 15V: 2.67A 40W / 3A 40W 3A1 3A 2.67A Not Offered 9V – 15V: 2.67A 80W / 5A 20W 3A1 2.22A 1.33A 1A 9V – 15V: 1.33A 15V – 20V: 1A 80W / 3A 20W 3A1 2.22A 1.33A 1A 9V – 15V: 1.33A 15V – 20V: 1A 40W / 5A 20W 3A1 2.22A 1.33A Not Offered 9V – 15V: 1.33A 40W / 3A 20W 3A1 2.22A 1.33A Not Offered 9V – 15V: 1.33A 80W/3A 15W 3A 1.67A2 1A2 0.75A2 9V - 15V: 1A2 15V - 20V: 0.75A2 40W/3A 15W 3A 1.67A2 1A2 Not offered 9V - 15V: 1A2 1) The Fixed Supply PDO Maximum Current field will Advertise at least 3A but May Advertise up to RoundUp (PDP/voltage) to the nearest 10mA. 2) These Capabilities are not required but may be offered at this Port Present PDP. Page 1000 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.2.1 Fixed Supply PDOs Figure 10.1, "SPR Source Power Rule Illustration for Fixed Supply PDOs" illustrates the minimum current that an SPR Source Shall support at each voltage for a given PDP Rating for Fixed Supply PDOs. Note: Not illustrated are that currents higher than 3A are allowed to be offered up to a limit of 5A given that a 5A cable is detected by the Source and the voltage times current remains within the Source PDP Rating. Figure 10.1 SPR Source Power Rule Illustration for Fixed Supply PDOs Figure 10.2, "SPR Source Power Rule Example For Fixed Supply PDOs" shows an example of an adapter with a rating at 50W. The adapter is required to support 20V at 2.5A, 15V at 3A, 9V at 3A and 5V at 3A. 0 1 2 3 4 5 6 0 10 20 30 40 50 60 70 80 90 100 5V 9V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 15W 27W 45W Source PDP Rating (W) Current (A) RP1 RP2 20V 5 + 9 + 15V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1001 Figure 10.2 SPR Source Power Rule Example For Fixed Supply PDOs Table 10.5, "Fixed Supply PDO - Source 5V", Table 10.6, "Fixed Supply PDO - Source 9V", Table 10.7, "Fixed Supply PDO - Source 15V" and Table 10.8, "Fixed Supply PDO - Source 20V" show the Fixed Supply PDOs that Shall be supported for each of the Normative voltages defined in Table 10.2, "SPR Normative Voltages and Minimum Currents". Table 10.5 Fixed Supply PDO - Source 5V Bit(s) Description B31…30 Fixed Supply B29 Dual-Role Power B28 USB Suspend Supported B27 Unconstrained Power B26 USB Communications Capable B25 Dual-Role Data B24 Unchunked Extended Messages Supported B23 EPR Capable B22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 5V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 15 x ÷ 5 15 < x ≤ 25 3 ≤ A ≤ x ÷ 5 25 < x ≤ 100 3 ≤ A ≤ 5 0 1 2 3 4 5 6 0 10 20 30 40 50 60 70 80 90 100 5V 9V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 15W 27W 45W Source PDP Rating (W) Current (A) RP1 RP2 50W 20V 5 + 9 + 15V Page 1002 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 More current May be offered in the PDOs when Optional voltages/currents are supported and a 5A cable is being used (see Section 10.2.3, "Optional Voltages/Currents"). Table 10.6 Fixed Supply PDO - Source 9V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 9V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 15 PDO not required 15 < x ≤ 27 x ÷ 9 27 < x ≤ 45 3 ≤ A ≤ x ÷ 9 45 < x ≤ 100 3 ≤ A ≤ 5 Table 10.7 Fixed Supply PDO - Source 15V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 15V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 27 PDO not required 27 < x ≤ 45 x ÷ 15 45 < x ≤ 75 3 ≤ A ≤ x ÷ 15 75 < x ≤ 100 3 ≤ A ≤ 5 Table 10.8 Fixed Supply PDO - Source 20V Bit(s) Description B31…30 Fixed Supply B29...22 Reserved – Shall be set to zero. B21…20 Peak Current B19…10 20V B9...0 Current based on PDP PDP Rating (x) Current (A) 0.5 ≤ x ≤ 45 PDO not required 45 < x ≤ 100 x ÷ 20 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1003 10.2.2.2 SPR Adjustable Voltage Supply (AVS) For SPR AVS, Figure 10.3, "Valid SPR AVS Operating Region for a Source advertising in the range of 27W < PDP ≤ 45W", Figure 10.4, "Valid SPR AVS Operating Region for a Source advertising in the range of 45W < PDP ≤ 60W" and Figure 10.5, "Valid SPR AVS Operating Region for a Source advertising in the range of 60W < PDP ≤ 100W" illustrate the valid operating region for SPR AVS RDO requests in the ranges of 27W < PDP ≤ 45W, 45W < PDP ≤ 60W and 60W < PDP ≤ 100W, respectively. Figure 10.3 Valid SPR AVS Operating Region for a Source advertising in the range of 27W < PDP ≤ 45W Figure 10.4 Valid SPR AVS Operating Region for a Source advertising in the range of 45W < PDP ≤ 60W 0 1 2 3 4 5 6 0 15 30 45 60 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V 15V Fixed PDO Max Current 15V 0 1 2 3 4 5 6 30 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V 15V Fixed PDO Max Current 15V 20V Fixed PDO Max Current (Minimum of 3A) Page 1004 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 10.5 Valid SPR AVS Operating Region for a Source advertising in the range of 60W < PDP ≤ 100W 10.2.2.2.1 SPR Adjustable Voltage Supply (AVS) Voltage Ranges Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" shows the Minimum and Maximum Voltage for the SPR AVS ranges. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. Table 10.9 SPR Adjustable Voltage Supply (AVS) Voltage Ranges AVS Voltage Range 15V AVS 20V AVS Maximum Voltage 15V 20V Minimum Voltage 9V 9V 0 1 2 3 4 5 6 30 RDO Current (A) RDO Voltage (V) Invalid Requests (Crosshatched Area) Valid Operating Region for SPR AVS Sink Requests for 27W < PDP чϰϱt Valid RDO Requests 20V 9V * At 15.0V, up to the (20V Fixed PDO Current)A is allowed 15V* 20V Fixed PDO Max Current 15V Fixed PDO Max Current Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1005 10.2.3 Optional Voltages/Currents 10.2.3.1 Optional Normative Fixed, Variable and Battery Supply In addition to the voltages and currents specified in Section 10.2.2, "Normative Voltages and Currents", an SPR Source that is optimized for use with a specific Sink or a specific class of Sinks May Optionally supply additional voltages and increased currents. However, the Optional voltages Shall Not exceed 9V. Optional voltages Shall Not be implemented on EPR Source including for both SPR Mode and EPR Modes of operation. EPR versions of Variable Supply and Battery Supply PDOs are not defined and Shall Not be implemented, however SPR Variable Supply and Battery Supply PDOs are allowed in EPR Mode. While allowed, the use of Optional voltages and currents is not recommended as two Sources with the same PDP Rating but not supporting the same Optional voltages and currents can behave differently thus confusing the user. See Section 10.2, "Source Power Rules" for the rules that Shall apply to Optional PDOs in order to be consistent with the declared PDP Rating and the Normative voltages and currents. 10.2.3.2 Optional Normative SPR Programmable Power Supply The voltages and currents a Programmable Power Supply with a PDP Rating of x Watts Shall support are as defined Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP". When Optional Programmable Power Supply APDOs are offered, the following requirements Shall apply:  A Source that Advertises Optional Programmable Power Supply APDOs Shall Advertise the PDOs and APDOs shown in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP".  A Source Shall Advertise Optional Programmable Power Supply APDOs with Maximum Voltage and Minimum Voltages for nominal voltage as defined in Table 10.11, "SPR Programmable Power Supply Voltage Ranges".  A Source Shall Not Advertise a Programmable Power Supply APDO that does not follow the Minimum Voltage and Maximum Voltage defined in Table 10.11, "SPR Programmable Power Supply Voltage Ranges".  In no case Shall a Source Advertise a current that exceeds the Attached cable's current rating.  The Max Voltage Shall Not exceed 21V while in SPR Mode. Table 10.10 SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP PDP Maximum PDP (W) SPR Fixed and AVS 9V Prog3 15V Prog3 20V Prog3 x < 15W Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) - - - 15W - - - 15 < x < 27W (PDP/9)A1 - - 27W 3A - - 27 < x < 45W 3A2 (PDP/15)A1 - 45W - 3A - 45 < x < 60W - 3A2 (PDP/20)A1 60W - - 3A 60 < x < 100W - - (PDP/20)A1 100W - - 5A 1) The SPR PPS APDOs Maximum Current field Shall Advertise RoundDown (PDP/Prog Voltage) to the nearest 50mA. 2) The SPR PPS APDOs Maximum Current field Shall Advertise at least 3A, but May Advertise up to RoundDown(PDP/Prog Voltage) to the nearest 50mA. 3) Applies to APDOs regardless of value of the PPS Power Limited bit. Page 1006 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.3.2.1 SPR Programmable Power Supply Voltage Ranges The SPR PPS Voltage ranges map to the Fixed Supply Voltages. For each fixed voltage there is a defined voltage range for the matching SPR PPS APDO. Table 10.11, "SPR Programmable Power Supply Voltage Ranges" shows the Minimum and Maximum Voltage for the Programmable Power Supply that corresponds to the Fixed nominal voltage. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. 10.2.3.2.2 Examples of the use of SPR Programmable Power Supplies The following examples illustrate what a power adapter that Advertises a particular PDP Rating May offer: 1) PDP 27W implementation includes:  5V @ 3A,  9V @ 3A, and  9V Prog @ 3A. 2) PDP 36W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 2.4A,  SPR AVS with 9V - 15V @ 2.4A,  9V Prog @ 3 A, and  15V Prog @ 2.4A. 3) PDP 36W implementation that Optionally includes higher current in the 9V Prog PPS:  5V @ 3A,  9V @ 3A,  15 @ 2.4A,  SPR AVS with 9V - 15V @ 2.4A,  9V Prog @ >3A up to 4A (with a 5A cable) and 15V  Prog @ 2.4A. 4) PDP 50W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 3A,  20V @ 2.5A, Table 10.11 SPR Programmable Power Supply Voltage Ranges Fixed Nominal Voltage 9V Prog 15V Prog 20V Prog Maximum Voltage 11V 16V 21V Minimum Voltage 5V 5V 5V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1007  SPR AVS with 9V - 15V @ 3A & 15V - 20V @ 2.5A,  15V Prog @ 3A, and  20V Prog @ 2.5A. 5) PDP 80W implementation includes:  5V @ 3A,  9V @ 3A,  15 @ 3A,  20V @ 4A,  SPR AVS with 9V - 15V @ 3A & 15V - 20V @ 4A,  15V Prog @ 3A, and  20V Prog @ 4A. The first example illustrates a basic example of a supply that can only support 5V and 9V. The second and third examples illustrates as the PDP Rating goes higher there are more possible combinations that meet the Power Rules. These examples also add SPR AVS. Although there are multiple ways to meet the Power Rules, while operating in SPR Mode no more than a combination of seven SPR (A)PDOs and APDOs can be offered. The fourth and fifth example show that the 15V Prog @ 3A fully covers the 9V Prog @3A range so it is not necessary to Advertise both. These examples also illustrate SPR AVS being extended up to 20V with separate current limits for the 9V - 15V and 15V - 20V ranges - a single SPR AVS APDO covers advertising both ranges. Page 1008 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 10.2.3.3 Optional Normative Extended Power Range (EPR) Support of EPR Mode is Optional. An EPR Capable port has a PDP Rating that is >100W and ≤ 240W. An EPR Capable Source Port (EPR Source Port) May operate in either SPR Mode or EPR Mode when operating at 100W or less. An EPR Source Port operating in SPR Mode May offer less than 100W to avoid violating safety regulations. When operating in EPR Mode, an EPR Source Port Shall offer 100W in Fixed 20V when not constrained by multi- port sharing limits. An EPR Source May include multiple ports and these ports can be functionally implemented as Shared Capacity Charger or Assured Capacity Charger ports as defined in [USB Type-C 2.4]. Any port on an EPR Source that has a Port Present PDP of 100W or less Shall follow the Normative requirements for SPR Source Ports and Shall operate only in SPR Mode. Any port on an EPR Source that is operating with a cable that is not EPR Capable Shall operate only in SPR Mode. An EPR Source, when operating in SPR Mode with a 5A cable, May offer less than 5A due to design tolerances in order to meet applicable safety standards. For best user experience it Should be as close to 100W as possible. Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" and Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR- capable cable" define the Normative requirements EPR Source Ports. While not included in these tables, any EPR Source Port that also supports SPR PPS Shall offer the SPR Fixed 20V PDO and PPS 20V Prog APDO at 100W (or the maximum available PDP when the port is operating at an Equivalent PDP <100W) when in EPR Mode:  When an EPR Source Port is capable of supplying its PDP Rating, it Shall adhere to the requirements defined in Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on its PDP Rating of x Watts.  When a Source Port on an EPR Charger is unable to provide its Port Maximum PDP, it Shall adhere to the requirements defined in Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable" based on a Port Present PDP of x Watts. Some examples:  An EPR Source Port May be unable to provide its PDP Rating because it is thermally constrained at the time of power Negotiation.  A Shared port on a multi-port EPR Charger that is limited by the remaining available power.  When an EPR Charger is in an Adjustable Voltage Supply (AVS) Explicit Contract:  It Shall Reject all Requests outside of the defined voltage range (see Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges") or for a requested voltage and Current that results in a power level that is more than the Port's Advertised PDP.  In no case Shall a Source Advertise a Current or accept a Current requested by a Sink that exceeds the Attached cable's current rating. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1009  The Max Voltage offered by an EPR Source Shall Not exceed 48V. Table 10.12 EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable Port Maximum PDP (W) SPR Fixed and AVS 28V Fixed 36V Fixed3 48V Fixed EPR AVS3, 4 100 < x ≤ 140 Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) (PDP/28)A2 N/A1 N/A1 (15V – PDP/5A):  5A (>PDP/5A – 28V):  (PDP/AVS voltage) A 140 < x ≤ 180 5A (PDP/ 36)A2 N/A1 (15V – PDP/5A):  5A (>PDP/5A – 36V):  (PDP/AVS voltage) A 180 < x ≤ 240 5A 5A (PDP/48)A2 (15V – PDP/5A):  5A (>PDP/5A – 48V):  (PDP/AVS voltage) A 1) EPR Sources are disallowed from offering Fixed Supply voltages that are above the defined voltages for a given PDP, e.g., 36V is disallowed for any PDP of 140W or lower. 2) The Fixed PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 3) EPR Sources Shall reject any request for more than the Advertised PDP, i.e., when output voltage and operating current requested in the Sink RDO is outside of the defined AVS voltage and current range represented by the Advertised PDP, the RDO will be rejected. 4) The current available for a given AVS voltage is as indicated in this column. The current defined here is describing the top edge of the Valid Operating Region as illustrated in Figure 10.6, "Valid EPR AVS Operating Region". The AVS APDO does not have a Maximum Current field, so the maximum current has to be calculated from the PDP. Page 1010 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Note: EPR Managed Capability Ports when power constrained are defined to offer higher voltages at lower Port Present PDP (as per Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable") than the port's Port Maximum PDP (as per Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable") because these voltages would otherwise be available if the Managed Capability Port power hadn't been constrained. Managed Capability Ports are required to be properly identified to the user based on the port's Port Maximum PDP. In reference to Table 10.13, "EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable", Table 10.14, "EPR Source Examples when Port Present PDP is less than Port Maximum PDP" gives examples of which EPR Capabilities, in addition to the required SPR Fixed Supply PDOs and SPR AVS APDO, are Advertised based on Port Present PDP and the port's Port Maximum PDP. Table 10.13 EPR Source Capabilities when Port Present PDP is less than Port Maximum PDP and using an EPR-capable cable Port Present PDP (W) SPR Fixed and AVS 28V Fixed 36V Fixed4 48V Fixed4 EPR AVS with Max Voltage of 28V, 36V or 48V per Table 10.122, 5, 6 28V 36V 48V 7.5 ≤ x ≤ 15 Required per Table 10.2, "SPR Normative Voltages and Minimum Currents" (or Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" when applicable) (PDP/28) A3 (PDP/36) A3 (PDP/48) A3  (15V – max voltage):  (PDP/AVS Voltage) A3 15 < x ≤ 27 27 < x ≤ 45 (PDP/28) A1 45 < x ≤ 60 (PDP/36) A1 60 < x ≤ 100 (PDP/48) A1 Up to 75W:  (15V – max voltage):  (PDP/AVS voltage) A Above 75W:  (15V – PDP/5A):  5A  (>PDP/5A – max voltage):  (PDP/AVS voltage) A 100 < x ≤ 140 Table 10.3, "SPR Source Capabilities When Port Present PDP is less than Port Maximum PDP" with a Port Present PDP of 100W. 140 < x ≤ 180 5A 180 < x ≤ 240 5A 5A 1) The Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/voltage) or RoundUp (PDP/voltage) to the nearest 10mA. 2) EPR Sources Shall reject any Request for more than the Advertised PDP, i.e., when output voltage and operating current requested in the Sink RDO is outside of the defined AVS voltage and current range represented by the Advertised PDP, the RDO will be rejected. 3) EPR Sources May offer an (A)PDOs at this Port Present PDP. When offered, the Fixed Supply PDOs Maximum Current field Shall Advertise either RoundDown (PDP/Voltage) or RoundUp (PDP/Voltage) to the nearest 10mA. 4) This EPR Fixed Supply voltage is only available if allowed by Table 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on the port’s PDP Rating. 5) The Max Voltage for AVS is what is allowed by TTable 10.12, "EPR Source Capabilities based on the Port Maximum PDP and using an EPR Capable Cable" based on the port’s Port Maximum PDP. 6) The current available based on AVS voltage is as indicated in this column. The current defined here is describing the top edge of the Valid Operating Region as illustrated in Figure 10.6, "Valid EPR AVS Operating Region". AVS APDO does not have a Maximum Current field so the maximum current has to be calculated from the PDP. Table 10.14 EPR Source Examples when Port Present PDP is less than Port Maximum PDP Port Maximum PDP Port Present PDP Offers 28V Fixed 36V Fixed 48V Fixed AVS 200W 108W 3.86A 3A 2.25A 48V@108W 160W 108W 3.86A 3A Not offered 36V@108W 120W 108W 3.86A Not offered Not offered 28V@108W 200W 72W 2.57A 2A 1.5A 48V@72W 160W 72W 2.57A 2A Not offered 36V@72W 120W 72W 2.57A Not offered Not offered 28V@72W 200W 36W 1.29A 1A1 0.75A1 48V@36W1 1) These Capabilities are not required but may be offered at this Port Present PDP. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1011 EPR Sources when operating in an AVS Explicit Contract are required to stay within their PDP as such they Shall respond to any request (VA) for more than the PDP with a Reject Message. Figure 10.6, "Valid EPR AVS Operating Region" illustrates the definition of the Valid operating range for an EPR Source operating in an AVS Explicit Contract based on its Advertised PDP. Figure 10.6 Valid EPR AVS Operating Region Figure 10.7, "EPR Source Power Rule Illustration for Fixed PDOs" illustrates the minimum current that an EPR Source Shall support at each voltage for a given PDP Rating. Note: Not illustrated are that currents higher than 3A are allowed to be offered up to a limit of 5A given that a 5A cable is detected by the Source and the voltage times current remains within the Source PDP Rating. 160W 36W 1.29A 1A1 Not offered 36V@36W1 120W 36W 1.29A Not offered Not offered 28V@36W Table 10.14 EPR Source Examples when Port Present PDP is less than Port Maximum PDP Port Maximum PDP Port Present PDP Offers 28V Fixed 36V Fixed 48V Fixed AVS 1) These Capabilities are not required but may be offered at this Port Present PDP. 0 1 2 3 4 5 6 0 15 30 45 60 RDO Current (A) RDO Voltage (V) 5A Invalid Requests (Crosshatched Area) Valid Operating Region for EPR AVS Sink Requests Valid RDO Requests Advertised Voltage = 28, 36 or 48V 15V Voltage = PDP/5A Current = Advertised PDP/Advertised Voltage Page 1012 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure 10.7 EPR Source Power Rule Illustration for Fixed PDOs 10.2.3.3.1 EPR Adjustable Voltage Supply (AVS) Voltage Ranges Table 10.15, "EPR Adjustable Voltage Supply (AVS) Voltage Ranges" shows the Minimum and Maximum Voltage for the EPR AVS ranges. The voltage output at the Source's connector Shall be +/-5% for both the Maximum Voltage and the Minimum Voltage. Table 10.15 EPR Adjustable Voltage Supply (AVS) Voltage Ranges AVS Voltage Ranges 28V AVS 36V AVS 48V AVS Maximum Voltage 28V 36V 48V Minimum Voltage 15V 15V 15V 0 1 2 3 4 5 6 0 20 40 60 80 100 Source PDP Rating (W) Current (A) 120 140 160 180 200 220 240 RP1 RP2 5V 15V 5 + 9V 5 + 9 + 15V 20V 7.5W 27W 45W 15W 100W 140W 180W 20V 9V 5 + 9 + 15V 5 + 9 + 15V 28V 36V 48V 5 + 9 + 15V 5 + 9 + 15V 20V 20+28V 20+28+36V Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1013 10.3 Sink Power Rules 10.3.1 Sink Power Rule Considerations The Sink Power Rules are designed to ensure the best possible user experience when a given Sink used with a compliant Source of arbitrary Output Power Rating that only supplies the Normative voltages and currents. The Sink Power Rules are based on the following considerations:  Low power Sources (e.g., 5V) are expected to be very common and will be used with Sinks designed for a higher PDP.  Optimizing the user experience when Sources with a higher PDP Rating are used with low power Sinks.  Preventing Sinks that only function well (or at all) when using Optional voltages and currents. 10.3.2 Normative Sink Rules Sinks designed to use Sources with a PDP Rating of x W Shall:  Either operate or charge from Sources that have a PDP Rating ≥ x W.  Either operate, charge or indicate a Capabilities Mismatch (see Section 6.4.2.3, "Capability Mismatch") from Sources that have a PDP Rating < x W and ≥ 0.5W. A Sink optimized for a Source with Optional voltages and currents or power as described in Section 10.2.3, "Optional Voltages/Currents" with a PDP Rating of x W Shall provide a similar user experience when powered from a Source with a PDP Rating of ≥ x W that supplies only the Normative voltages and currents as specified in Section 10.2.2, "Normative Voltages and Currents". For example, a 60W Source might not offer 9V Prog or 15V Prog since 20V Prog is a suitable substitute for both (as shown in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP"). The Operational Current/Power in the Sink Capabilities PDO for Sinks with an Operational PDP of x Watts Shall be as follows:  Operational current for Fixed Supply/Variable Supply PDOs: RoundDown(x/voltage) to the nearest 10mA.  Operational power for Battery Supply PDOs: ≤ x.  Operational current for Programmable Power Supply APDOs as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP": RoundDown (x/Prog Voltage) to the nearest 50mA. The Maximum Current/Power in the Sink RDO for Sinks with an Operational PDP of x Watts and Maximum PDP of y Watts Shall be as follows:  Maximum current for Fixed Supply/Variable Supply RDOs from Sinks without a Battery: RoundDown(x/ voltage) to the nearest 10mA.  Maximum current for Fixed Supply/Variable Supply RDOs from Sinks with a Battery: RoundDown(y/ Voltage) to the nearest 10mA.  Maximum power for Battery Supply RDOs from Sinks without a Battery: ≤ x.  Maximum power for Battery Supply RDOs from Sinks with a Battery: ≤ y.  Maximum current for PPS Supply RDOs from Source PDOs as defined in Table 10.10, "SPR Programmable Power Supply PDOs and APDOs based on the Port Maximum PDP" or Table 10.14, "EPR Source Examples when Port Present PDP is less than Port Maximum PDP": RoundDown (y/Prog Voltage) to the nearest 50mA. The following requirements Shall apply to the Advertised Sink Capabilities: Page 1014 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10  A Sink Shall Not Advertise Fixed Supply PDO maximum voltages and currents that exceed the PDP Rating they were designed to use.  A Sink Shall Not Advertise Variable Supply PDO maximum voltages and currents that exceed the PDP Rating they were designed to use.  A Sink Shall Not Advertise a Battery Supply PDO maximum allowable power that exceeds the PDP Rating they were designed to use.  A Sink Shall Not Advertise a PPS APDO maximum allowable power that exceeds the PDP Rating they were designed to use.  A Sink Shall Not Advertise an AVS APDO maximum allowable power that exceeds the PDP Rating they were designed to use. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1015 A CRC calculation A.1 C code example // // USB PD CRC Demo Code. // #include <stdio.h> int crc; //----------------------------------------------------------------------------- void crcBits(int x, int len) { const int poly = 0x04C11DB6; //spec 04C1 1DB7h int newbit, newword, rl_crc; for(int i=0; i<len; i++) { newbit = ((crc>>31) ^ ((x>>i)&1)) & 1; if(newbit) newword=poly; else newword=0; rl_crc = (crc<<1) | newbit; crc = rl_crc ^ newword; printf("%2d newbit=%d, x>>i=0x%x, crc=0x%x\n", i, newbit,(x>>i),crc); } } int crcWrap(int c){ int ret = 0; int j, bit; c = ~c; printf("~crc=0x%x\n", c); for(int i=0;i<32;i++) { j = 31-i; bit = (c>>i) & 1; ret |= bit<<j; } return ret; } //----------------------------------------------------------------------------- int main(){ int txCrc=0,rxCrc=0,residue=0,data; printf("using packet data 0x%x\n", data=0x0101); crc = 0xffffffff; crcBits(data,16); txCrc = crcWrap(crc); printf("crc=0x%x, txCrc=0x%x\n", crc, txCrc); printf("received packet after decode= 0x%x, 0x%x\n", data, txCrc); crc = 0xffffffff; crcBits(data,16); rxCrc = crcWrap(crc); printf("Crc of the received packet data is (of course) =0x%x\n", rxCrc); printf("continue by running the transmit crc through the crc\n"); crcBits(rxCrc,32); printf("Now the crc residue is 0x%x\n", crc); printf("should be 0xc704dd7b\n"); } Page 1016 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 B Message Sequence Examples (Deprecated) This appendix has been Deprecated. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1017 C VDM Command Examples C.1 Discover Identity Example C.1.1 Discover Identity Command request Table C.1, "Discover Identity Command request from Initiator Example" below shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending a Discover Identity Command request. Table C.1 Discover Identity Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) 0xFF00 (PD SID) B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 1 (Discover Identity) Page 1018 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.1.2 Discover Identity Command response - Active Cable. Table C.2, "Discover Identity Command response from Active Cable Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder returning VDOs in response to a Discover Identity Command request. In this illustration, the Responder is an active Gen2 cable which supports Modal Operation. Table C.2 Discover Identity Command response from Active Cable Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 5 (VDM Header + ID Header VDO + Cert Stat VDO + Product VDO + Cable VDO) 11…9 MessageID 0…7 8 Cable Plug 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) 0xFF00 (PD SID) B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 2 (Discover Identity) ID Header VDO B31 USB Communications Capable as USB Host 0 (not USB Communications capable as a USB Host) B30 USB Communications Capable as a USB Device 0 (not data capable as a Device) B29…27 SOP’ Product Type (Cable Plug/VPD) 100b (Active Cable) B26 Modal Operation Supported 1 (supports Modes) B25…16 Reserved. Shall be set to zero. 0 B15…0 16-bit unsigned integer. USB Vendor ID USB-IF assigned VID for this cable vendor Cert Stat VDO B31…0 32-bit unsigned integer USB-IF assigned XID for this cable Product VDO B31…16 16-bit unsigned integer. USB Product ID Product ID assigned by the cable vendor B15…0 16-bit unsigned integer. bcdDevice Device version assigned by the cable vendor Cable VDO1 (returned for Product Type “Active Cable”) B31…28 HW Version Cable HW version number (vendor defined) B27…24 Firmware Version Cable FW version number (vendor defined) B23…21 VDO Version 010b (Version 1.2) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1019 B20 Reserved 0 B19…18 USB Type-C plug to USB Type-C/Captive 10b (USB Type-C®) B17 EPR Capable (Active Cable) 0 (not EPR Capable) B16…13 Cable Latency 0001b (<10ns (~1m)) B12…11 Cable Termination Type (Active Cable) 11b (Both ends Active, VCONN required) B10…9 Maximum VBUS Voltage (Active Cable) 00b (20V) B8 SBU Supported 0 (SBUs connections supported) B7 SBU Type 0 (SBU is passive) B6…5 VBUS Current Handling Capability (Active Cable) 01b (3A) B4 VBUS Through Cable 1 (Yes) B3 SOP’’ Controller Present 1 (SOP’’ controller present) B2…0 Reserved 0 Cable VDO2 (returned for Product Type “Active Cable”) B31…24 Maximum Operating Temperature 70 B23…16 Shutdown Temperature 80 B15 Reserved 0 B14…12 U3/CLd Power 010b (1-5mW) B11 U3 to U0 transition mode 00b (U3 to U0 direct) B10 Physical connection 0 (Copper) B9 Active element 0 (Active Re-driver) B8 USB4 Supported 0 (USB4 Supported) B7…6 USB 2.0 Hub Hops Consumed 2 B5 USB 2.0 Supported 0 ([USB 2.0] supported) B4 USB 3.2 Supported 0 ([USB 3.2] SuperSpeed supported) B3 USB Lanes Supported 1b (Two lanes) B2 Optically Isolated Active Cable 0 (Not supported) B1 USB4 Asymmetric Mode Supported 0 (Not Supported) B0 USB Gen 1b (Gen 2 or higher) Table C.2 Discover Identity Command response from Active Cable Responder Example Bit(s) Field Value Page 1020 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.1.3 Discover Identity Command response - Hub. Table C.3, "Discover Identity Command response from Hub Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder returning VDOs in response to a Discover SVIDs Command request. In this illustration, the Responder is a Hub. Table C.3 Discover Identity Command response from Hub Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 4 (VDM Header + ID Header VDO + Cert Stat VDO + Product VDO) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) 0xFF00 (PD SID) B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 2 (Discover Identity) ID Header VDO B31 USB Communications Capable as USB Host 0 (not USB Communications capable as a USB Host) B30 USB Communications Capable as a USB Device 1 (data capable as a Device) B29…27 SOP’ Product Type (Cable Plug/VPD) 001b (Hub) B26 Modal Operation Supported 0 (doesn’t support Modes) B25…16 Reserved. Shall be set to zero. 0 B15…0 16-bit unsigned integer. USB Vendor ID USB-IF assigned VID for this Hub vendor Cert Stat VDO B31…0 32-bit unsigned integer USB-IF assigned XID for this Hub Product VDO B31…16 16-bit unsigned integer. USB Product ID Product ID assigned by the Hub vendor B15…0 16-bit unsigned integer. bcdDevice Device version assigned by the Hub vendor Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1021 C.2 Discover SVIDs Example C.2.1 Discover SVIDs Command request Table C.4, "Discover SVIDs Command request from Initiator Example" below shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending a Discover SVIDs Command request. Table C.4 Discover SVIDs Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) 0xFF00 (PD SID) B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 2 (Discover SVIDs) Page 1022 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.2.2 Discover SVIDs Command response Table C.5, "Discover SVIDs Command response from Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder returning VDOs in response to a Discover SVIDs Command request. In this illustration, the value 3 in the Message Header Number of Data Objects field indicates that one VDO containing the supported SVIDs would be returned followed by a terminating VDO. Note: The last VDO returned (the terminator of the transmission) contains zero value SVIDs. If a SVID value is zero, it is not used. Table C.5 Discover SVIDs Command response from Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 3 (VDM Header + 2*VDO) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) 0xFF00 (PD SID) B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 2 (Discover SVIDs) VDO 1 B31…16 SVID 0 SVID value B15…0 SVID 1 SVID value VDO 2 B31…16 SVID 2 0x0000 B15…0 SVID 3 0x0000 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1023 C.3 Discover Modes Example C.3.1 Discover Modes Command request Table C.6, "Discover Modes Command request from Initiator Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending a Discover Modes Command request. The Initiator of the Discover Modes Command AMS sends a Message Header with the Number of Data Objects field set to 1 followed by a VDM Header with the Command Type (B7…6) set to zero indicating the Command is from an Initiator and the Command (B4…0) is set to 3 indicating Mode discovery. Table C.6 Discover Modes Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for which Modes are being requested B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 3 (Discover Modes) Page 1024 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.3.2 Discover Modes Command response The Responder to the Discover Modes Command request returns a Message Header with the Number of Data Objects field set to a value of 1 to 7 (the actual value is the number of Mode objects plus one) followed by a VDM Header with the Command Type (B7…6) set to 1 indicating the Command is from a Responder and the Command (B4…0) set to 3 indicating the following objects describe the Modes the device supports. If the ID is a VID, the structure and content of the VDO is left to the vendor. If the ID is a SID, the structure and content of the VDO is defined by the Standard. Table C.7, "Discover Modes Command response from Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder returning VDOs in response to a Discover Modes Command request. In this illustration, the value 2 in the Message Header Number of Data Objects field indicates that the device is returning one VDO describing the Mode it supports. It is possible for a Responder to report up to six different Modes. Table C.7 Discover Modes Command response from Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 2 (VDM Header + 1 Mode VDO) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for which Modes were requested B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 000b B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 3 (Discover Modes) Mode VDO B31…0 Mode 1 Standard or Vendor defined Mode value Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1025 C.4 Enter Mode Example C.4.1 Enter Mode Command request The Initiator of the Enter Mode Command request sends a Message Header with the Number of Data Objects field set to 1 followed by a VDM Header with the Command Type (B7…6) set to 0 indicating the Command is from an Initiator and the Command (B4…0) set to 4 to request the Responder to enter its mode of operation and sets the Object Position field to the desired functional VDO based on its offset as received during Discovery. Table C.8, "Enter Mode Command request from Initiator Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending an Enter Mode Command request. Table C.8 Enter Mode Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for the Mode being entered B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (a one in this field indicates a request to enter the first Mode in list returned by Discover Modes) B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 4 (Enter Mode) Page 1026 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.4.2 Enter Mode Command response The Responder that is the target of the Enter Mode Command request sends a Message Header with the Number of Data Objects field set to a value of 1 followed by a VDM Header with the Command Type (B7…6) set to 1 indicating the Command is from a Responder and the Command (B4…0) set to 4 indicating the Responder has entered the Mode and is ready to operate. Table C.9, "Enter Mode Command response from Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder sending an Enter Mode Command response with an ACK. Table C.9 Enter Mode Command response from Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for the Mode entered B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (offset of the Mode entered) B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 4 (Enter Mode) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1027 C.4.3 Enter Mode Command request with additional VDO. The Initiator of the Enter Mode Command request sends a Message Header with the Number of Data Objects field set to 2 indicating an additional VDO followed by a VDM Header with the Command Type (B7…6) set to zero indicating the Command is from an Initiator and the Command (B4…0) set to 4 to request the Responder to enter its mode of operation and sets the Object Position field to the desired functional VDO based on its offset as received during Discovery. Table C.10, "Enter Mode Command request with additional VDO Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending an Enter Mode Command request with an additional VDO. Table C.10 Enter Mode Command request with additional VDO Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for the Mode being entered B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (a one in this field indicates a request to enter the first Mode in list returned by Discover Modes) B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 4 (Enter Mode) Including Optional Mode specific VDO B31…0 Mode specific Page 1028 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.5 Exit Mode Example C.5.1 Exit Mode Command request The Initiator of the Exit Mode Command request sends a Message Header with the Number of Data Objects field set to 1 followed by a VDM Header with the Command Type (B7…6) set to zero indicating the Command is from an Initiator and the Command (B4…0) set to 5 to request the Responder to exit its Mode of operation. Table C.11, "Exit Mode Command request from Initiator Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending an Exit Mode Command request. Table C.11 Exit Mode Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for the Mode being exited B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (identifies the previously entered Mode by its Object Position that is to be exited) B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 5 (Exit Mode) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1029 C.5.2 Exit Mode Command response The Responder that receives the Exit Mode Command request sends a Message Header with the Number of Data Objects field set to a value of 1 followed by a VDM Header with the Command Type (B7…6) set to 1 indicating the Command is from a Responder and the Command (B4…0) set to 5 indicating the Responder has exited the Mode and has returned to normal USB operation. Table C.12, "Exit Mode Command response from Responder Example" shows the contents of the key fields in the Message Header and VDM Header for a Responder sending an Exit Mode Command ACK response. Table C.12 Exit Mode Command response from Responder Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for the Mode exited B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (offset of the Mode to be exited) B7…6 Command Type 01b (Responder ACK) B5 Reserved 0 B4…0 Command 5 (Exit Mode) Page 1030 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 C.6 Attention Example C.6.1 Attention Command request The Initiator of the Attention Command request sends a Message Header with the Number of Data Objects field set to 1 followed by a VDM Header with the Command Type (B7…6) set to zero indicating the Command is from an Initiator and the Command (B4…0) set to 6 to request attention from the Responder. Table C.13, "Attention Command request from Initiator Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending an Attention Command request. Table C.13 Attention Command request from Initiator Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 1 (VDM Header) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for which attention is being requested B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (offset of the Mode requesting attention) B7…6 Command Type 00b (Initiator) B5 Reserved 0 B4…0 Command 6 (Attention) Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1031 C.6.2 Attention Command request with additional VDO. The Initiator of the Attention Command request sends a Message Header with the Number of Data Objects field set to 2 indicating an additional VDO followed by a VDM Header with the Command Type (B7…6) set to zero indicating the Command is from a Responder and the Command (B4…0) set to 6 to request attention from the Responder. Table C.14, "Attention Command request from Initiator with additional VDO Example" shows the contents of the key fields in the Message Header and VDM Header for an Initiator sending an Attention Command request with an additional VDO. Table C.14 Attention Command request from Initiator with additional VDO Example Bit(s) Field Value Message Header 15 Reserved 0 14…12 Number of Data Objects 2 (VDM Header + VDO) 11…9 MessageID 0…7 8 Port Power Role 0 or 1 7…6 Specification Revision 10b (Revision 3.x) 5…4 Reserved 0 3…0 Message Type 1111b (Vendor Defined Message) VDM Header B31…16 Standard or Vendor ID (SVID) SVID for which attention is being requested B15 VDM Type 1 (Structured VDM) B14…13 Structured VDM Version (Major) 01b (Version 2.0) B12…11 Structured VDM Version (Minor) 01b (Version 2.1) B10…8 Object Position 001b (offset of the Mode requesting attention) B7…6 Command Type 000b (Initiator) B5 Reserved 0 B4…0 Command 6 (Attention) Including Optional Mode specific VDO B31…0 Mode specific Page 1032 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 D BMC Receiver Design Examples The BMC signal is DC-coupled so that the voltage level is affected by the ground IR Drop. The DC offset of the BMC signal at Power Source and Power Sink are in the opposite directions. When the VBUS current is increased from 0A, the BMC signal waveform shifts downward at Power Sink and shifts upward at Power Source. This section introduces two sample BMC receiver circuit implementations, which are immune from DC offset and high current load step. They can be used in Power Source, Power Sink and inside cables. D.1 Finite Difference Scheme D.1.1 Sample Circuitry The sample Finite Difference BMC receiver shown in Figure D.1, "Circuit Block of BMC Finite Difference Receiver"consists of the Rx bandwidth limiting filter with the time constant tRxFilter, a sampler with the sampling step ΔtS, 50ns, a Finite Difference Calculator which calculates the voltage difference between the time interval of ΔtFD, 300ns, an edge detector controlled by two voltage thresholds, Vth, H and Vth, L and a logic block for bit recognition. Figure D.1 Circuit Block of BMC Finite Difference Receiver D.1.2 Theory This section describes the fundamental theory of Finite Difference Scheme to recover the received BMC signal with the input and output signal waveforms of the circuit blocks shown in Figure D.1, "Circuit Block of BMC Finite Difference Receiver". To illustrate the robustness of the implementation, the VBUS current load step rate is intentionally increased to 2A/µs at the Sink load. In Figure D.2, "BMC AC and DC noise from VBUS at Power Sink" (a), the red curve represents the VBUS current measured at the Power Sink when the current is increased at 9 µs from 0A to 5A and the blue dash curve represents the VBUS current measured at the USB Type-C ®connector of the power Sink. In this example, the peak current overshoot with larger load step rate is increased to 518 mA which exceeds iOvershoot. Figure D.2, "BMC AC and DC noise from VBUS at Power Sink" (b) shows the total BMC noise at Power Sink, coupled from VBUS and D+/D- through the worst [USB Type-C 2.4] compliant cable, after the Rx bandwidth limiting filter with the time constant tRxFilter is applied. The noise can be decomposed into 3 components. The first is the DC offset, IVBUS(t)*RGND, while IVBUS is the VBUS current and RGND is the ground DC resistance of the cable. The offset is negative in Power Sink and positive at Power Source. The second noise component is the inductive VBUS noise, M*d IVBUS(t)/dt, while M is the mutual inductance between the VBUS and CC wires in the cable and d IVBUS(t)/ dt is the load step rate. The third component is [USB 2.0] Full Speed SE0 coupling noise which would normally occur randomly but was assumed to occur periodically in the simulation to account for the crosstalk in any phase between the BMC and [USB 2.0] signals. In Figure D.3, "Sample BMC Signals (a) without USB 2.0 SE0 Noise (b) with USB 2.0 SE0 Noise", the blue dash curve represents the BMC signal when there is no VBUS current, and the red solid curve represents the BMC signal affected by the VBUS coupling noise shown in Figure D.2, "BMC AC and DC noise from VBUS at Power Sink"(b). The green solid curve is the sample [USB 2.0] noise, after the Rx bandwidth limiting filter with the time constant tRxFilter is applied. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1033 Figure D.2 BMC AC and DC noise from VBUS at Power Sink Figure D.3 Sample BMC Signals (a) without USB 2.0 SE0 Noise (b) with USB 2.0 SE0 Noise The BMC signals shown in Figure D.3, "Sample BMC Signals (a) without USB 2.0 SE0 Noise (b) with USB 2.0 SE0 Noise" are sampled every 50ns and the scaled derivative waveforms, Vcc(t) - Vcc (t - 50ns), without and with [USB 2.0] noise are shown in Figure D.4, "Scaled BMC Signal Derivative with 50ns Sampling Rate (a) without USB 2.0 Noise (b) with USB 2.0 Noise" (a) and (b), respectively. In Figure D.4, "Scaled BMC Signal Derivative with 50ns Sampling Rate (a) without USB 2.0 Noise (b) with USB 2.0 Noise" (a), if there is no [USB 2.0] noise, the derivative waveform just changes slightly before and after the VBUS current transition. That means, the slope of the BMC waveform is not sensitive to the DC offset and is very useful to be used to design a robust receiver against a large DC offset. However, the derivative waveforms with [USB 2.0] noise have large perturbation as shown in Figure D.4, "Scaled BMC Signal Derivative with 50ns Sampling Rate (a) without USB 2.0 Noise (b) with USB 2.0 Noise" (b). Page 1034 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure D.4 Scaled BMC Signal Derivative with 50ns Sampling Rate (a) without USB 2.0 Noise (b) with USB 2.0 Noise To remove the high frequency content of the [USB 2.0] noise, Finite Difference technique with the proper time interval is applied to the BMC waveform with [USB 2.0] noise in Figure D.3, "Sample BMC Signals (a) without USB 2.0 SE0 Noise (b) with USB 2.0 SE0 Noise". Using Backward Finite Difference Calculator, ΔVcc = Vcc (t) - Vcc(t- Δt), Figure D.5, "BMC Signal and Finite Difference Output with Various Time Steps" shows the Finite Difference Output while Δt = 500ns. The larger the time interval Δt is, the larger the peak-to-peak magnitude of the Finite Difference Output will be. However, the time interval is bounded by the rise time of the BMC signal so that 300ns to 500ns is a good range of the time interval. Figure D.5 BMC Signal and Finite Difference Output with Various Time Steps D.1.3 Data Recovery The edge detection is followed by the Finite Difference Calculation. At the input of the edge detector, if the voltage is larger than Vth, H at the rising edge, the output will become high voltage level, VH, if the voltage is smaller than Vth, L at the falling edge, the output will become low voltage level, VL. In this example, Vth, H and Vth, L are 0.2V and -0.2V, respectively. The solid curve in Figure D.6, "Output of Finite Difference in dash line and Edge Detector in solid line" represents the output of the edge detector, where VH is 0.5V and VL is -0.5V. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1035 Figure D.6 Output of Finite Difference in dash line and Edge Detector in solid line The duty cycle of the output signal from the edge detector varies depending on the thresholds, Vth, H and Vth, L, as well as jitter and noise from silicon and channel. The techniques such as integrating receiver can be used to recover the BMC signal. D.1.4 Noise Zone and Detection Zone Figure D.7, "Noise Zone and Detect Zone of BMC Receiver" shows the output of Finite Difference when the time interval of Finite Difference is set to 300ns. The noise Zone is defined in between +Vnoise and -Vnoise, in which the noise glitches occur. The detect zone is defined in between +Vdetect and -Vdetect, excluding the noise zone. The thresholds of the edge detectors, Vth, H and Vth, L, must be properly set within the detect zone so that the data can be recovered successfully. In this example, Vdetect is 250mV and Vnoise is 50mV. It is highly recommended that the product implemented with the similar techniques indicates the performance with the range of Vnoise and Vdetect in the electrical specification. Figure D.7 Noise Zone and Detect Zone of BMC Receiver Page 1036 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 D.2 Subtraction Scheme D.2.1 Sample Circuitry The sample Subtraction BMC receiver shown in Figure D.8, "Circuit Block of BMC Subtraction Receiver" consists of the two Low Pass Filters (LPF1 and LPF2), a Subtractor, an Edge Detector and a logic block for bit recognition. The time constant of the first and second LPF are 200ns and 300ns, respectively. The Subtractor subtracts the LPF1 output from the LPF2 output. The Edge Detector controlled by two voltage thresholds, Vth, H and Vth, L to recover the data. Figure D.8 Circuit Block of BMC Subtraction Receiver D.2.2 Output of Each Circuit Block Figure D.9, "(a) Output of LPF1 and LPF2 (b) Subtraction of LPF1 and LPF2 Output" (a) shows the output of LPF1 as the red solid line and LPF2 as the blue dash line as well as the [USB 2.0] noise in green solid line. Figure D.9, "(a) Output of LPF1 and LPF2 (b) Subtraction of LPF1 and LPF2 Output" (b) shows the voltage difference between the two output filters, Vdiff = Vcc_afterLPF1 - Vcc_afterLPF2. The Vdiff waveform looks very similar to the Finite Difference output waveform shown in Figure D.6, "Output of Finite Difference in dash line and Edge Detector in solid line" so that the data recovery method through the edge detector is the same as described in Section D.1.3, "Data Recovery". Figure D.9 (a) Output of LPF1 and LPF2 (b) Subtraction of LPF1 and LPF2 Output D.2.3 Subtractor Output at Power Source and Power Sink The following figures shows the example when the VBUS current increases from 0A to 5A and then decreases to 0A with high load step rate. The output of the LPF1 and the Subtractor at Power Source and Power Sink are shown in Figure D.10, "Output of the BMC LPF1 in blue dash curve and the Subtractor in red solid curve (a) at Power Source (b) at Power Sink" (a) and (b), respectively. Although the BMC signals at Power Source and Power Sink shift toward the opposite direction, the Subtractor outputs at Power Source and Power Sink are almost identical disregard of the opposite direction of the DC offset. Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1037 Figure D.10 Output of the BMC LPF1 in blue dash curve and the Subtractor in red solid curve (a) at Power Source (b) at Power Sink D.2.4 Noise Zone and Detection Zone The zone definition is the same as defined in Section D.1.4, "Noise Zone and Detection Zone". The sizes of the noise zone and detection zone of the Subtraction Scheme are dependent on the filter time constant. When the time constant of the first and second LPF are 200ns and 300ns, respectively, Vdetect is 250mV and Vnoise is 50mV. It is highly recommended that the product implemented with the similar techniques indicates the performance with the range of Vnoise and Vdetect in the electrical specification. Page 1038 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 E FRS System Level Example E.1 Overview Appendix E, "FRS System Level Example" is intended to clarify Fast Role Swap (FRS) functionality at the system level through the use of an example implementation. Figure E.1, "Example FRS Capable System" is an example of a Hub and laptop implementation that supports Fast Role Swap (see Figure 7.16, "VBUS Power during Fast Role Swap"). It is not the only possible Hub or laptop architecture. However, it is intended to provide an example system whose functionality is used here to illustrate how Fast Role Swap works. Figure E.1 Example FRS Capable System This appendix describes two cases that cover a variety of behaviors that might be seen in practice.  Slow VBUS Discharge where VBUS between the Hub and the laptop takes more than 15ms (tFRSwapInit) to discharge below 5.5 V (vSafe5V (max)). In this case the FR_Swap Message is sent by the laptop while VBUS is still greater than vSafe5V (max). See Figure E.2, "Slow VBUS Discharge".  Fast VBUS Discharge where VBUS between the Hub and the laptop discharges very quickly, perhaps be- fore the Fast Role Swap Request is even complete. See Figure E.3, "Fast VBUS Discharge". However, neither the Hub nor the laptop can anticipate how quickly VBUS will discharge until the power adapter is disconnected from an AC Supply or it is unplugged from the Hub. The Fast Role Swap Request is the momentary low driven by the Hub on the CC wire which is detected by the laptop. Figure E.2, "Slow VBUS Discharge" and Figure E.3, "Fast VBUS Discharge" show the voltage seen on VBUS in relationship to the Fast Role Swap Request They also show the transition between when the Hub stops supplying VBUS and when the laptop starts supplying VBUS. Notebook чϵϬ F F ϱs  2 VB Hub чϭϬ F F ϱs  F WŽƌƚϭ ŽŶƚƌŽůůĞƌ FRS  4 VB  1 VB ĚĞƚĞĐƚ ƐŝŐŶĂů Power Adapter F  Peripheral  3 VB чϭϬ F FRS WŽƌƚϮ ŽŶƚƌŽůůĞƌ ĚĞƚĞĐƚ ^ŽƵƌĐĞŽŶ ^ŽƵƌĐĞŽĨĨ ŵŽŶŝƚŽƌ ŵŽŶŝƚŽƌ ,ŽůĚͲhƉĂƉ ,ϭ H3 ,Ϯ H4 Eϭ N3 N4 EϮ VHubVB VNbVB чϭϬ F ^ŝŶŬŽĨĨ ŚĂƌŐĞƌ ŚŽůĚ ĂƚƚĞƌLJ ƚŝŵĞƌ H5 H6 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1039 Figure E.2 Slow VBUS Discharge Old Voltage 0V vSafe5V(min) tSrcFRSwap у New Source may turn on at any time after VBUS falls below vSafe5V(max) VBUS at Hub & Notebook Old Source detects power loss and signals Fast Role Swap tFRSwapTx CC N3 H2 N1 vSafe5V(max) VBUS voltage when it discharges slowly (assume very small cable IR drop prior to FR swap) VBUS at Notebook VBUS at Hub 0A +3A Current from Notebook to Hub In this example the Notebook is drawing little current prior to the FRS signaling. In other cases it may be drawing more current. Cable IR drop O H1 N2 N4 <iSnkStdby tSnkFRSwap Page 1040 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure E.3 Fast VBUS Discharge Cable IR drop Cable IR drop H2 Old Voltage 0V vSafe5V(min) tSrcFRSwap Old Source sends Fast Role Swap signal tFRSwapRx VBUS at Notebook CC VBUS voltage when it discharges quickly N4 vSafe5V(max) VBUS at Hub N2 0A -5A +3A In this example the Notebook is drawing 5A prior to the FRS signaling. In other cases it may be drawing less current. Current from Notebook to Hub N1 tSnkFRSwap <iSnkStdby Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1041 E.2 FRS Initial Setup Before a Fast Role Swap can occur, some initial setup steps are required. They require the laptop to discover whether Fast Role Swap is supported by the Hub, the amount of current the Hub requires after a Fast Role Swap, and whether the laptop is able and willing to provide that amount. They also ensure that the laptop supplies VCONN before, during and after an FRS. Table E.1, "Sequence for setup of a Fast Role Swap (Hub connected to Power Adapter first)" and Table E.2, "Sequence for setup of a Fast Role Swap (Hub connected to laptop before Power Adapter)" below show two typical sequences that might be used to prepare a laptop to support Fast Role Swap. Table E.1 Sequence for setup of a Fast Role Swap (Hub connected to Power Adapter first) Step # Hub Laptop 1 Hub connected to power adapter 2 Hub is connected to laptop. 3 Laptop sources 5 V to VBUS (vSafe5V). Laptop sources 5 V to VCONN 4 Laptop reads the cable to check its current carrying capability and/or if it is an Active Cable requiring VCONN. 5 Laptop sends a Capabilities Message 6 Hub sends a Request Message 7 Hub and laptop establish an Explicit Contract with Hub as Sink. 8 Laptop sends a Get_Source_Cap Message to determine how much power the Hub can provide. 9 Hub sends a Source_Capabilities Message with the Dual-Role Power bit set, and Unconstrained Power bit set, and Maximum Current > 0. 10 Since the Hub can supply power the laptop sends a PR_Swap Message 11 Hub sends an Accept Message and starts supplying VBUS 12 Laptop sends a Get_Sink_Cap Message to determine the current required by the Hub to support an FRS. If the Hub does not support FRS or the laptop cannot supply the required current, the laptop Ignores any Fast Role Swap Requests it might see. 13 If the Hub can supply more than 3A, it initiates a VCONN Swap to make to make itself the VCONN Source and reads the cable to check its current carrying capability. 14 Hub sends a Sink_Capabilities Message 15 Laptop sends a Request Message 16 Hub and laptop establish an Explicit Contract with Hub as source. Page 1042 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 17 If the laptop has detected that it is connected via an Active Cable (or one that supports Alternate Modes) and/or that it can support an FRS, it initiates a VCONN Swap to make itself the VCONN Source. This removes a requirement that the Hub to hold up VCONN during the FRS. 18 Normal PD Power traffic flow 19 The Hub and laptop are now ready to do a Fast Role Swap in case the power adapter gets removed. Table E.2 Sequence for setup of a Fast Role Swap (Hub connected to laptop before Power Adapter) Step # Hub Laptop 0 Hub is connected to laptop. 1 Laptop sources 5 V to VBUS (vSafe5V). Laptop sources 5 V to VCONN 2 Laptop reads the cable to check its current carrying capability and/or if it is an Active Cable requiring VCONN. 3 Laptop sends Source_Capabilities Message 4 Hub sends Request Message 5 Hub and laptop establish an Explicit Contract with Hub as Sink. 6 Laptop sends a Get_Source_Cap Message to determine how much power the Hub can provide 7 Hub sends a Source_Capabilities Message with the Dual-Role Power bit set, and Unconstrained Power bit cleared, and Maximum Current = 0. 8 Since the Hub cannot supply power, the laptop does not send a PR_Swap Message 9 The power adapter is connected to the Hub 10 If the Hub can source more than 3A, it initiates a VCONN Swap to become the VCONN Source. 11 Hub reads the e-marker to determine the cable’s current carrying capability. 12 Hub initiates a Power Role Swap to become the Source 13 Hub sends a Source_Capabilities Message with the Unconstrained Power bit set and Maximum Current > 0. 14 Hub and laptop establish an Explicit Contract with Hub as source. 15 Laptop sends a Get_Sink_Cap Message to determine the current required by the Hub to support an FRS. If the Hub does not support FRS or the laptop cannot supply the required current, the laptop Ignores any Fast Role Swap Requests it might see. Table E.1 Sequence for setup of a Fast Role Swap (Hub connected to Power Adapter first) Step # Hub Laptop Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1043 16 If the laptop has detected that it is connected via an Active Cable (or one that supports Alternate Modes) and/or that it can support an FRS, it initiates a VCONN Swap to make itself the VCONN Source. This removes a requirement that the Hub also hold up VCONN during the FRS. 17 The Hub and laptop are now ready to do a Fast Role Swap in case the power adapter gets removed. Table E.2 Sequence for setup of a Fast Role Swap (Hub connected to laptop before Power Adapter) Step # Hub Laptop Page 1044 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 E.3 FRS Process After the initial setup is completed and the laptop has determined both that the Hub can request FRS and that the laptop is able and willing to supply the requested current, the system is ready to support FRS. This section describes the sequence of events that take place during a Fast Role Swap. The following figures and tables do not cover the actions of the Device Policy Manager or the Policy Engine. Those actions occur orthogonally to the electrical events shown in this appendix. However, the diagrams do indicate the inputs/outputs where the DPM and Policy Engine interact with the electrical events:  The laptop sends the FR_Swap Message to initiate the FRS AMS (see Figure 7.43, "Transition Diagram for Fast Role Swap") within 15ms after the laptop detects the Fast Role Swap Request on CC.  The laptop sends the final PS_RDY Message in the FRS AMS only after it is sourcing VBUS. Figure E.4 Slow VBUS discharge after FR_Swap message is sent discharging to vSafe5V(max) Notebook: FRS signal detected Old Sink (old current) New Sink (0.5A, 0.9A, 1.5A, or 3.0A) Adapter Hub Power Path Notebook Power Path VBUS Voltage VBUS Current Power Path Interaction Source VBUS Voltage Sink VBUS Current Hub: Adapter Mains Loss Detected New Source = vSafe5V Sink Source Hub: VBUS > vSafe5V (min) and sinking Notebook: Sourcing 5V Source vSafe5V Wait to Source Sink Waiting to Sink Turning on Source Signals to/ from DPM & Policy Engine Hub: Send FRS signal H1 H2 N1 N4 N3 Notebook: Initiates FRS message sequence Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1045 Table E.3 Sequence for slow VBUS discharge (it discharges after FR_Swap message is sent) Step # Hub Laptop 1 The power adapter’s AC Supply power is lost. 2 Hub detects the power adapter disconnect (H1) as quickly as possible. 3 Hub sends Fast Role Swap Request on CC (H2) and starts monitoring VHubVB (H3). Hub also starts a tSnkFRSwap timer after the FRS signal begins and VBUS has fallen below vSafe5V (min). 4 Laptop detects Fast Role Swap Request on CC (N1) that triggers sending of the FR_Swap Message. This can happen at any point in the following steps so long as it is within 15 ms (tFRSwapInit). 5 Laptop opens the sinking switch (N2), as quickly as possible to minimize power drained from Hub after the Fast Role Swap Request. 6 Laptop begins monitoring VBUS (N3) to know when to turn the laptop into a Source . 7 Hub opens the sourcing switch (H4) while VHubVB > 5.5V (after the Fast Role Swap Request is sent). However, the sourcing switch (H4) must be kept closed until VHubVB is as close to 5.5V as possible. It is important for the Hub to open its sourcing switch (H4) before the laptop’s sourcing switch (N4) gets closed to minimize inrush current. 8 Hub closes the switch (H5) to use the hold-up capacitor to supply VBUS to the peripheral(s). Systems with a holding cap permanently in place do not need the switch (H5). Hub does not draw more than iSnkStdby from VBUS, until the tSnkFRSwap timer expires. 9 Laptop detects VBUS < VNbVB (N1) before closing the sourcing switch (N4) when VNbVB is as close as possible to 5.5V. This minimizes the time when VBUS is not sourced. 10 Laptop closes sourcing switch (N4). When this occurs the Hub’s input capacitance on VBUS will be less than 10F (cSnkBulk). 11 Hub’s tSnkFRSwap timer expires (H6). 12 Hub draws up to the current it Advertised in the Fast Role Swap required USB Type-C Current field of its Sink_Capabilities Message. 13 Hubs with (H5) will open (H5) and remove the Hold- Up capacitor. Page 1046 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Figure E.5 VBUS discharges quickly before FR_Swap message is sent after adapter disconnected Table E.4 VBUS discharges quickly after adapter disconnected Step # Hub Laptop 1 The power adapter is Detached from the Hub. 2 Hub detects power adapter disconnect (H1) causing VHubVB to drop below 5.5V very rapidly. 3 Hub sends Fast Role Swap Request on CC (H2) and starts monitoring VHubVB (H3). Hub opens sourcing switch (H4). Hub also starts a tSnkFRSwap timer. 4 Hub closes the switch (H5) to use the hold-up capacitor to supply VBUS to the peripheral(s). Systems with a holding cap permanently in place do not need the switch (H5). Hub does not draw more than iSnkStdby from VBUS, until the tSnkFRSwap timer expires. 5 Laptop detects Fast Role Swap Request on CC (N1) that triggers sending of the FR_Swap Message. This can happen at any point in the following steps so long as it is within 15 ms (tFRSwapInit). 6 Laptop opens the sinking switch (N2), as quickly as possible to minimize power drained from Hub after the Fast Role Swap Request. 7 Laptop begin monitoring VBUS (N3) to know when to turn the laptop into a Source . Hub: Start Fast Swap Signal Notebook: FRS signal detected Old Sink New Sink (0.5A, 0.9A, 1.5A, or 3.0A) Adapter Sink Port Device Policy Mgr Sink Port Power Path Source Port Voltage Sink Port Current Signals to/ from DPM & policy engine Source Port Interaction Sink Port Interaction Source VBUS Voltage Sink VBUS Current Hub: Adapter Detached Detected New Source = vSafe5V Sink Source Hub: VBUS < vSafe5V (max) Source vSafe5V Turning On Source Sink H1 H2 N1 H4 Waiting to Sink vSafe5V (max) Hub: VBUS > vSafe5V and sinking Notebook: Sourcing 5V N4 N3 N2 Universal Serial Bus Power Delivery Specification, Revision 3.2, Version 1.1, 2024-10 Page 1047 8 Laptop detects VBUS < VNbVB (N3). 9 Laptop closes sourcing switch (N4). When this occurs the Hub’s input capacitance on VBUS will be less than 10 F (cSnkBulk). 10 Hub’s tSnkFRSwap timer expires (H6). 11 Hub draws up to the current it Advertised in the Fast Role Swap required USB Type-C Current field of its Sink_Capabilities Message. 12 Hubs with (H5) will open (H5) and remove the Hold- Up capacitor. Table E.4 VBUS discharges quickly after adapter disconnected Step # Hub Laptop